A Layer 2 VPN Network YANG Model
draft-ietf-opsawg-l2nm-08

Document Type Active Internet-Draft (opsawg WG)
Authors samier barguil  , Oscar de Dios  , Mohamed Boucadair  , Luis Munoz 
Last updated 2021-10-11
Replaces draft-barguil-opsawg-l2sm-l2nm
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OPSAWG                                                        S. Barguil
Internet-Draft                                  O. Gonzalez de Dios, Ed.
Intended status: Standards Track                              Telefonica
Expires: 14 April 2022                                 M. Boucadair, Ed.
                                                                  Orange
                                                                L. Munoz
                                                                Vodafone
                                                         11 October 2021

                    A Layer 2 VPN Network YANG Model
                       draft-ietf-opsawg-l2nm-08

Abstract

   This document defines an L2VPN Network YANG Model (L2NM) that can be
   used to manage the provisioning of Layer 2 Virtual Private Network
   (VPN) services within a network (e.g., service provider network).
   The L2NM complements the Layer 2 Service Model (L2SM) by providing a
   network-centric view of the service that is internal to a service
   providers.  The L2NM is particularly meant to be used by a network
   controller to derive the configuration information that will be sent
   to relevant network devices.

   Also, the document defines the initial versions of two IANA-
   maintained modules that defines a set of identities of BGP Layer 2
   encapsulation types and pseudowire types.

Editorial Note (To be removed by RFC Editor)

   Please update these statements within the document with the RFC
   number to be assigned to this document:

   *  "This version of this YANG module is part of RFC XXXX;"

   *  "RFC XXXX: Layer 2 VPN Network Model";

   *  reference: RFC XXXX

   Please update "RFC CCCC" to the RFC number to be assigned to I-
   D.ietf-opsawg-vpn-common.

   Also, please update the "revision" date of the YANG modules.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

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   This Internet-Draft will expire on 14 April 2022.

Copyright Notice

   Copyright (c) 2021 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
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   provided without warranty as described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   4
   3.  Acronyms  . . . . . . . . . . . . . . . . . . . . . . . . . .   6
   4.  Reference Architecture  . . . . . . . . . . . . . . . . . . .   6
   5.  Relation with other YANG Models . . . . . . . . . . . . . . .  10
   6.  Description of the Ethernet Segment YANG Module . . . . . . .  11
   7.  Description of the L2NM YANG Module . . . . . . . . . . . . .  13
     7.1.  Overall Structure of the Module . . . . . . . . . . . . .  14
     7.2.  VPN Profiles  . . . . . . . . . . . . . . . . . . . . . .  14
     7.3.  VPN Services  . . . . . . . . . . . . . . . . . . . . . .  16
     7.4.  Global Parameters Profiles  . . . . . . . . . . . . . . .  20
     7.5.  VPN Nodes . . . . . . . . . . . . . . . . . . . . . . . .  23
       7.5.1.  BGP Auto-Discovery  . . . . . . . . . . . . . . . . .  26
       7.5.2.  Signaling Options . . . . . . . . . . . . . . . . . .  27
         7.5.2.1.  BGP . . . . . . . . . . . . . . . . . . . . . . .  29
         7.5.2.2.  LDP . . . . . . . . . . . . . . . . . . . . . . .  30
         7.5.2.3.  L2TP  . . . . . . . . . . . . . . . . . . . . . .  31
     7.6.  VPN Network Accesses  . . . . . . . . . . . . . . . . . .  32
       7.6.1.  Connection  . . . . . . . . . . . . . . . . . . . . .  34
       7.6.2.  EVPN-VPWS Service Instance  . . . . . . . . . . . . .  36

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       7.6.3.  Ethernet OAM  . . . . . . . . . . . . . . . . . . . .  37
       7.6.4.  Services  . . . . . . . . . . . . . . . . . . . . . .  39
   8.  YANG Modules  . . . . . . . . . . . . . . . . . . . . . . . .  44
     8.1.  IANA BGP Layer 2 Encapsulation Types  . . . . . . . . . .  44
     8.2.  IANA Encapsulation Types  . . . . . . . . . . . . . . . .  49
     8.3.  Ethernet Segments . . . . . . . . . . . . . . . . . . . .  56
     8.4.  L2NM  . . . . . . . . . . . . . . . . . . . . . . . . . .  65
   9.  Security Considerations . . . . . . . . . . . . . . . . . . . 114
   10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 115
     10.1.  YANG Modules . . . . . . . . . . . . . . . . . . . . . . 115
     10.2.  BGP Layer 2 Encapsulation Types  . . . . . . . . . . . . 116
     10.3.  Pseudowire Types . . . . . . . . . . . . . . . . . . . . 117
   11. References  . . . . . . . . . . . . . . . . . . . . . . . . . 118
     11.1.  Normative References . . . . . . . . . . . . . . . . . . 118
     11.2.  Informative References . . . . . . . . . . . . . . . . . 121
   Appendix A.  Examples . . . . . . . . . . . . . . . . . . . . . . 125
     A.1.  BGP-based VPLS  . . . . . . . . . . . . . . . . . . . . . 126
     A.2.  BGP-based VPWS with LDP Signaling . . . . . . . . . . . . 131
     A.3.  LDP-based VPLS  . . . . . . . . . . . . . . . . . . . . . 134
     A.4.  VPWS-EVPN Service Instance  . . . . . . . . . . . . . . . 139
     A.5.  Automatic ESI Assignment  . . . . . . . . . . . . . . . . 145
     A.6.  VPN Network Access Precedence . . . . . . . . . . . . . . 148
   Appendix B.  Initial BGP Layer 2 Encapsulation Types  . . . . . . 151
   Appendix C.  Initial PW Types . . . . . . . . . . . . . . . . . . 151
   Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . . 153
   Contributors  . . . . . . . . . . . . . . . . . . . . . . . . . . 153
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . . 153

1.  Introduction

   [RFC8466] defines an L2VPN Service Model (L2SM) YANG data model that
   can be used for Layer 2 Virtual Private Network (L2VPN) service
   ordering matters between customers and service providers.  This
   document complements the L2SM by creating a network-centric view of
   the service: the L2VPN Network Model (L2NM).

   The L2NM (Section 8.4) can be exposed, for example, by a network
   controller to a service controller within the service providers
   network.  In particular, the model can be used in the communication
   interface between the entity that interacts directly with the
   customer, the service orchestrator (either fully automated or a human
   operator), and the entity in charge of network orchestration and
   control (a.k.a., network controller/orchestrator) by allowing for
   more network-centric information to be included.

   The L2NM supports capabilities, such as exposing operational
   parameters, transport protocols selection, and precedence.  It can
   also serve as a multi-domain orchestration interface.

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   The L2NM is scoped for a variety of Layer 2 Virtual Private Networks
   such as:

   *  Virtual Private LAN Service (VPLS) [RFC4761][RFC4762]
   *  Virtual Private Wire Service (VPWS) (Section 3.1.1 of [RFC4664])
   *  Various flavors of Ethernet VPNs (EVPNs):
      -  VPWS EVPN [RFC8214],
      -  Provider Backbone Bridging Ethernet VPNs (PBB EVPNs) [RFC7623],
      -  EVPN over MPLS [RFC7432], and
      -  EVPN over VxLAN [RFC8365].

   The L2NM is designed to easily support future Layer 2 VPN flavors and
   procedures.  A set of examples to illustrate the use of the L2NM are
   provided in Appendix A.

   Also, the document defines the initial versions of two IANA-
   maintained modules that define a set of identities of BGP Layer 2
   encapsulation types (Section 8.1) and pseudowire types (Section 8.2).
   Relying upon these IANA-maintained modules is meant to provide more
   flexibility in handling new types rather than be limited by a set of
   identities defined in the L2NM itself.  Section 8.3 defines a YANG
   module to manage Ethernet Segments (ESes) that are required for
   instantiating EVPNs.

   This document uses the common Virtual Private Network (VPN) YANG
   module defined in [I-D.ietf-opsawg-vpn-common].

   The YANG data models in this document conforms to the Network
   Management Datastore Architecture (NMDA) defined in [RFC8342].

2.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

   This document assumes that the reader is familiar with [RFC6241],
   [RFC7950], [RFC8466], and [RFC8309].  This document uses terminology
   from those documents.

   This document uses the term "network model" defined in Section 2.1 of
   [RFC8969].

   The meaning of the symbols in YANG tree diagrams is defined in
   [RFC8340].

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   This document makes use of the following terms:

   Ethernet Segment (ES):  Refers to the set of the Ethernet links that
      are used by a customer site (device or network) to connect to one
      or more Provider Edges (PEs).

   Layer 2 VPN Customer Service Model (L2SM):  Describes the service
      characterization of an L2VPN that interconnects a set of sites
      from the customer's perspective.  The customer service model does
      not provide details on the service provider network.  An L2VPN
      customer service model is defined in [RFC8466].

   Layer 2 VPN Service Network Model (L2NM):  Refers to the YANG module
      that describes an L2VPN service with a network-centric view.  It
      contains information of the service provider network and might
      include allocated resources.  Network controllers can use it to
      manage the Layer 2 VPN service configuration in the service
      providers network.  The YANG module can be consumed by a service
      orchestrator to request a VPN service to a network controller or
      to expose the list of active L2VPN services.

   Network controller:  Denotes a functional entity responsible for the
      management of the service provider network.

   Service orchestrator:  Refers to a functional entity that interacts
      with the customer of an L2VPN relying upon, e.g., L2SM.  The
      service orchestrator is responsible of the CE-PE attachment
      circuits, the PE selection, and requesting the activation of the
      L2VPN service to a network controller.

   Service Provider Network:  Is a network able to provide L2VPN-related
      services.

   VPN network access:  Is an abstraction that represents the network
      interfaces that are associated to a given VPN node.  Traffic
      coming from the VPN network access belongs to the VPN.  The
      attachment circuits (bearers) between Customer Edges (CEs) and
      Provider Edges (PEs) are terminated in the VPN network access.

   VPN node:  Is an abstraction that represents a set of policies
      applied on a PE and that belong to a single VPN service.  A VPN
      service involves one or more VPN nodes.  The VPN node will
      identify the service providers node on which the VPN is deployed.

   VPN service provider:  Is a service provider that offers L2VPN-
      related services.

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3.  Acronyms

   The following acronyms are used in the document:

   ACL     Access Control List
   BGP     Border Gateway Protocol
   CE      Customer Edge
   ES      Ethernet Segment
   ESI     Ethernet Segment Identifier
   EVPN    Ethernet VPN
   L2VPN   Layer 2 Virtual Private Network
   L2SM    L2VPN Service Model
   L2NM    L2VPN Network Model
   MAC     Media Access Control
   PBB     Provider Backbone Bridging
   PE      Provider Edge
   QoS     Quality of Service
   RD      Route Distinguisher
   RT      Route Target
   VPLS    Virtual Private LAN Service
   VPN     Virtual Private Network
   VPWS    Virtual Private Wire Service
   VRF     Virtual Routing and Forwarding

4.  Reference Architecture

   Figure 1 illustrates how the L2NM is used.  As a reminder, this
   figure is an expansion of the architecture presented in Section 3 of
   [RFC8466] and decomposes the box marked "orchestration" in that
   figure into three separate functional components called "Service
   Orchestration", "Network Orchestration", and "Domain Orchestration".

   The reader may refer to [RFC8309] for the distinction between the
   "Customer Service Model", the "Service Delivery Model", the "Network
   Configuration Model", and the "Device Configuration Model".  The
   "Domain Orchestration" and "Config Manager" roles may be performed by
   "SDN Controllers".

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                             +---------------+
                             |   Customer    |
                             +-------+-------+
             Customer Service Model  |
                 e.g., l2vpn-svc     |
                             +-------+-------+
                             |    Service    |
                             | Orchestration |
                             +-------+-------+
              Network Model          |
   l2vpn-ntw + ietf-ethernet-segment |
                             +-------+-------+
                             |   Network     |
                             | Orchestration |
                             +-------+-------+
       Network Configuration Model   |
                         +-----------+-----------+
                         |                       |
                +--------+------+       +--------+------+
                |    Domain     |       |     Domain    |
                | Orchestration |       | Orchestration |
                +---+-----------+       +--------+------+
     Device         |        |                   |
     Configuration  |        |                   |
     Model          |        |                   |
               +----+----+   |                   |
               | Config  |   |                   |
               | Manager |   |                   |
               +----+----+   |                   |
                    |        |                   |
                    | NETCONF/CLI..................
                    |        |                   |
             +------------------------------------------------+
                                 Network

                            +++++++
                            + AAA +
                            +++++++

    ++++++++   Bearer    ++++++++           ++++++++      ++++++++
    + CE A + ----------- + PE A +           + PE B + ---- + CE B +
    ++++++++  Connection ++++++++           ++++++++      ++++++++

               Site A                               Site B

                    Figure 1: L2SM and L2NM Interaction

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   The customer may use various means to request a service that may
   trigger the instantiation of an L2NM.  The customer may use the L2SM
   or may rely upon more abstract models to request a service that
   relies upon an L2VPN service.  For example, the customer may supply
   an IP Connectivity Provisioning Profile (CPP) that characterizes the
   requested service [RFC7297], an enhanced VPN (VPN+) service
   [I-D.ietf-teas-enhanced-vpn], or an IETF network slice service
   [I-D.ietf-teas-ietf-network-slices].

   Note also that both the L2SM and the L2NM may be used in the context
   of the Abstraction and Control of TE Networks (ACTN) framework
   [RFC8453].  Figure 2 shows the Customer Network Controller (CNC), the
   Multi-Domain Service Coordinator (MDSC), and the Provisioning Network
   Controller (PNC).

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                  +----------------------------------+
                  | Customer                         |
                  | +-----------------------------+  |
                  | |             CNC             |  |
                  | +-----------------------------+  |
                  +----+-----------------------+-----+
                       |                       |
                       | L2SM                  | L2SM
                       |                       |
             +---------+---------+   +---------+---------+
             | MDSC              |   |       MDSC        |
             | +---------------+ |   |     (parent)      |
             | |    Service    | |   +---------+---------+
             | | Orchestration | |             |
             | +-------+-------+ |             | L2NM
             |         |         |             |
             |         | L2NM    |   +---------+---------+
             |         |         |   |       MDSC        |
             | +-------+-------+ |   |      (child)      |
             | |    Network    | |   +---------+---------+
             | | Orchestration | |             |
             | +---------------+ |             |
             +---------+---------+             |
                       |                       |
                       | Network Configuration |
                       |                       |
          +------------+-------+     +---------+------------+
          | Domain             |     |           Domain     |
          | Controller         |     |           Controller |
          |       +---------+  |     |    +---------+       |
          |       |   PNC   |  |     |    |   PNC   |       |
          |       +---------+  |     |    +---------+       |
          +------------+-------+     +---------+------------+
                       |                       |
                       | Device Configuration  |
                       |                       |
                  +----+---+              +----+---+
                  | Device |              | Device |
                  +--------+              +--------+

               Figure 2: L2SM and L2NM in the Context of ACTN

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5.  Relation with other YANG Models

   The "ietf-vpn-common" module [I-D.ietf-opsawg-vpn-common] includes a
   set of identities, types, and groupings that are meant to be reused
   by VPN-related YANG modules independently of the layer (e.g., Layer
   2, Layer 3) and the type of the module (e.g., network model, service
   model) including future revisions of existing models (e.g.,
   [RFC8466]).  The L2NM reuses these common types and groupings.

   Also, the L2NM uses the IANA-maintained modules "iana-bgp-l2-encaps"
   (Section 8.1) and "iana-pseudowire-types" (Section 8.2) to identify a
   layer 2 encapsulation type.

   For the particular case of EVPN, the L2NM includes a name that refers
   to an Ethernet segment that is created using the "ietf-ethernet-
   segment" module (Section 8.3).  Some ES-related examples are provided
   in Appendices A.4 and A.5.

   As discussed in Section 4, the L2NM is meant to manage L2VPN services
   within a service provider network.  The module provides a network
   view of the service.  Such a view is only visible within the service
   provider and is not exposed outside (to customers, for example).  The
   following discusses how L2NM interfaces with other YANG modules:

   L2SM:  L2NM is not a customer service model.

      The internal view of the service (i.e., L2NM) may be mapped to an
      external view which is visible to customers: L2VPN Service YANG
      data Model (L2SM) [RFC8466].

      The L2NM can be fed with inputs that are requested by customers,
      typically, relying upon an L2SM template.  Concretely, some parts
      of the L2SM module can be directly mapped into L2NM while other
      parts are generated as a function of the requested service and
      local guidelines.  Finally, there are parts local to the service
      provider and do not map directly to L2SM.

      Note that the use of the L2NM within a service provider does not
      assume nor preclude exposing the VPN service via the L2SM.  This
      is deployment-specific.  Nevertheless, the design of L2NM tries to
      align as much as possible with the features supported by the L2SM
      to ease grafting both L2NM and L2SM for the sake of highly
      automated VPN service provisioning and delivery.

   Network Topology Modules:  An L2VPN involves nodes that are part of a
      topology managed by the service provider network.  Such topology
      can be represented using the network topology module in [RFC8345].

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   Device Modules:  L2NM is not a device model.

      Once a global VPN service is captured by means of the L2NM, the
      actual activation and provisioning of the VPN service will involve
      a variety of device modules to tweak the required functions for
      the delivery of the service.  These functions are supported by the
      VPN nodes and can be managed using device YANG modules.  A non-
      comprehensive list of such device YANG modules is provided below:

      *  Interfaces [RFC8343].

      *  BGP [I-D.ietf-idr-bgp-model].

      *  MPLS [RFC8960].

      *  ACLs [RFC8519].

      How the L2NM is used to derive device-specific actions is
      implementation-specific.

6.  Description of the Ethernet Segment YANG Module

   The 'ietf-ethernet-segment' module (Figure 3) is used to manage a set
   of Ethernet segments in the context of an EVPN service.

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    module: ietf-ethernet-segment
      +--rw ethernet-segments
         +--rw ethernet-segment* [name]
            +--rw name                                 string
            +--rw esi-type?                            identityref
            +--rw (esi-choice)?
            |  +--:(directly-assigned)
            |  |  +--rw ethernet-segment-identifier?   yang:hex-string
            |  +--:(auto-assigned)
            |     +--rw esi-auto
            |        +--rw (auto-mode)?
            |        |  +--:(from-pool)
            |        |  |  +--rw esi-pool-name?                string
            |        |  +--:(full-auto)
            |        |     +--rw auto?                         empty
            |        +--ro auto-ethernet-segment-identifier?
            |                yang:hex-string
            +--rw esi-redundancy-mode?                 identityref
            +--rw df-election
            |  +--rw df-election-method?   identityref
            |  +--rw preference?           uint16
            |  +--rw revertive?            boolean
            |  +--rw election-wait-time?   uint32
            +--rw split-horizon-filtering?             boolean
            +--rw pbb
            |  +--rw backbone-src-mac?   yang:mac-address
            +--rw member* [ne-id interface-id]
               +--rw ne-id           string
               +--rw interface-id    string

                 Figure 3: Ethernet Segments Tree Structure

   In reference to the structure shown in Figure 3, the following data
   nodes can be included:

   'name':  Sets a name to uniquely identify an ES with a service
      provider network.  This name is referenced in the VPN network
      access level of the L2NM (Section 7.6).

   'esi-type':  Indicates the Ethernet Segment Identifier (ESI) type as
      discussed in Section 5 of [RFC7432].  ESIs can be automatically
      assigned either with or without indicating a pool from which an
      ESI should be taken.  The following types are supported:

      'esi-type-0':  The ESI is directly configured by the VPN service
         provider.

      'esi-type-1':  The ESI is auto-generated from the IEEE 802.1AX

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         Link Aggregation Control Protocol (LACP) [IEEE802.1AX].

      'esi-type-2':  The ESI is auto-generated and determined based on
         the Layer 2 bridge protocol.

      'esi-type-3':  The ESI is a MAC-based ESI value that can be auto-
         generated or configured by the VPN service provider.

      'esi-type-4':  The ESI is auto-generated or configured by the VPN
         service provider based on the Router-ID.  The 'router-id'
         supplied in Section 7.5 can be used to auto-derive an ESI when
         this type is used.

      'esi-type-5':  The ESI is auto-generated or configured by the VPN
         service provider based on the Autonomous System (AS) number.
         The 'local-autonomous-system' supplied in Section 7.4 can be
         used to auto-derive an ESI when this type is used.

   'esi-redundancy-mode':  Specifies the EVPN redundancy mode for a
      given ES.  The following modes are supported: Single-Active
      (Section 14.1.1 of [RFC7432]) or All-Active (Section 14.1.2 of
      [RFC7432]).

   'df-election':  Specifies a set of parameters related to the
      Designated Forwarder (DF) election (Section 8.5 of [RFC7432]).
      For example, this data node can be used to indicate an election
      method (e.g., [RFC8584] or [I-D.ietf-bess-evpn-pref-df]).  If no
      election method is indicated, the default one defined in
      Section 8.5 of [RFC7432] is used.

   'split-horizon-filtering':  Controls the activation of the split-
      horizon filtering for an ES (Section 8.3 of [RFC7432]).

   'backbone-src-mac':  Associates a Provider Backbone MAC (B-MAC)
      address with an ES.  This is particularly useful for All-Active
      multihomed ESes (Section 9.1 of [RFC7623]).

   'member':  Lists the members of an ES in a service provider network.

7.  Description of the L2NM YANG Module

   The L2NM ('ietf-l2vpn-ntw', Section 8.4) is meant to manage L2VPNs
   within a service provider network.  In particular, the 'ietf-l2vpn-
   ntw' module can be used to create, modify, delete and retrieve L2VPN
   services in a network controller.  The module is designed to minimize
   the amount of customer-related information.

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   The full tree diagram of the module can be generated using the
   "pyang" tool [PYANG].  That tree is not included here because it is
   too long (Section 3.3 of [RFC8340]).  Instead, subtrees are provided
   for the reader's convenience.

7.1.  Overall Structure of the Module

   The 'ietf-l2vpn-ntw' module uses two main containers: 'vpn-profiles'
   and 'vpn-services' (see Figure 4).

   The 'vpn-profiles' container is used by the provider to maintain a
   set of common VPN profiles that apply to one or several VPN services
   (Section 7.2).

   The 'vpn-services' container maintains the set of L2VPN services
   managed in the service provider network.  The module allows creating
   a new L2VPN service by adding a new instance of 'vpn-service'.  The
   'vpn-service' is the data structure that abstracts the VPN service
   (Section 7.3).

            module: ietf-l2vpn-ntw
              +--rw l2vpn-ntw
                 +--rw vpn-profiles
                 |  ...
                 +--rw vpn-services
                    +--rw vpn-service* [vpn-id]
                       ...
                       +--rw vpn-nodes
                          +--rw vpn-node* [vpn-node-id]
                             ...
                             +--rw vpn-network-accesses
                                +--rw vpn-network-access* [id]
                                   ...

                   Figure 4: Overall L2NM Tree Structure

7.2.  VPN Profiles

   The 'vpn-profiles' container (Figure 5) is used by a VPN service
   provider to define and maintain a set of VPN profiles
   [I-D.ietf-opsawg-vpn-common] that apply to one or several VPN
   services.

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            +--rw l2vpn-ntw
               +--rw vpn-profiles
               |  +--rw valid-provider-identifiers
               |     +--rw external-connectivity-identifier* [id]
               |     |       {external-connectivity}?
               |     |  +--rw id    string
               |     +--rw encryption-profile-identifier* [id]
               |     |  +--rw id    string
               |     +--rw qos-profile-identifier* [id]
               |     |  +--rw id    string
               |     +--rw bfd-profile-identifier* [id]
               |     |  +--rw id    string
               |     +--rw forwarding-profile-identifier* [id]
               |     |  +--rw id    string
               |     +--rw routing-profile-identifier* [id]
               |        +--rw id    string
               +--rw vpn-services
                  ...

                  Figure 5: VPN Profiles Subtree Structure

   This document does not make any assumption about the exact definition
   of these profiles.  The exact definition of the profiles is local to
   each VPN service provider.  The model only includes an identifier to
   these profiles in order to ease identifying and binding local
   policies when building a VPN service.  As shown in Figure 5, the
   following identifiers can be included:

   'external-connectivity-identifier':  This identifier refers to a
      profile that defines the external connectivity provided to a VPN
      service (or a subset of VPN sites).  An external connectivity may
      be an access to the Internet or a restricted connectivity such as
      access to a public/private cloud.

   'encryption-profile-identifier':  An encryption profile refers to a
      set of policies related to the encryption schemes and setup that
      can be applied when building and offering a VPN service.

   'qos-profile-identifier':  A Quality of Service (QoS) profile refers
      to as set of policies such as classification, marking, and actions
      (e.g., [RFC3644]).

   'bfd-profile-identifier':  A Bidirectional Forwarding Detection (BFD)
      profile refers to a set of BFD [RFC5880] policies that can be
      invoked when building a VPN service.

   'forwarding-profile-identifier':  A forwarding profile refers to the

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      policies that apply to the forwarding of packets conveyed within a
      VPN.  Such policies may consist, for example, at applying Access
      Control Lists (ACLs).

   'routing-profile-identifier':  A routing profile refers to a set of
      routing policies that will be invoked (e.g., BGP policies) when
      delivering the VPN service.

7.3.  VPN Services

   The 'vpn-service' is the data structure that abstracts an L2VPN
   service in the service provider network.  Each 'vpn-service' is
   uniquely identified by an identifier: 'vpn-id'.  Such 'vpn-id' is
   only meaningful locally within the network controller.  The subtree
   of the 'vpn-services' is shown in Figure 6.

          +--rw vpn-services
             +--rw vpn-service* [vpn-id]
                +--rw vpn-id                        vpn-common:vpn-id
                +--rw vpn-name?                     string
                +--rw vpn-description?              string
                +--rw customer-name?                string
                +--rw parent-service-id?            vpn-common:vpn-id
                +--rw vpn-type?                     identityref
                +--rw vpn-service-topology?         identityref
                +--rw bgp-ad-enabled?               boolean
                +--rw signaling-type?               identityref
                +--rw global-parameters-profiles
                |  ...
                +--rw underlay-transport
                |  +--rw (type)?
                |     +--:(abstract)
                |     |  +--rw transport-instance-id?   string
                |     |  +--rw instance-type?           identityref
                |     +--:(protocol)
                |        +--rw protocol*                identityref
                +--rw status
                |  +--rw admin-status
                |  |  +--rw status?         identityref
                |  |  +--rw last-change?   yang:date-and-time
                |  +--ro oper-status
                |     +--ro status?         identityref
                |     +--ro last-change?   yang:date-and-time
                +--rw vpn-nodes
                   ...

                       Figure 6: VPN Services Subtree

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   The description of the VPN service data nodes that are depicted in
   Figure 6 are as follows:

   'vpn-id':  Is an identifier that is used to uniquely identify the
      L2VPN service within L2NM scope.

   'vpn-name':  Associates a name with the service in order to
      facilitate the identification of the service.

   'vpn-description':  Includes a textual description of the service.

      The internal structure of a VPN description is local to each VPN
      service provider.

   'customer-name':  Indicates the name of the customer who ordered the
      service.

   'parent-service-id':  Refers to an identifier of the parent service
      (e.g., L2SM, IETF network slice, VPN+) that triggered the creation
      of the L2VPN service.  This identifier is used to easily correlate
      the (network) service as built in the network with a service
      order.  A controller can use that correlation to enrich or
      populate some fields (e.g., description fields) as a function of
      local deployments.

   'vpn-type':  Indicates the L2VPN type.  The following types, defined
      in [I-D.ietf-opsawg-vpn-common], can be used for the L2NM:

      'vpls':  Virtual Private LAN Service (VPLS) as defined in
         [RFC4761] or [RFC4762].

      'vpws':  Virtual Private Wire Service (VPWS) as defined in
         Section 3.1.1 of [RFC4664].

      'vpws-evpn':  VPWS as defined in [RFC8214].

      'pbb-evpn':  Provider Backbone Bridging (PBB) EVPNs as defined in
         [RFC7623].

      'mpls-evpn':  MPLS-based EVPNs [RFC7432].

      'vxlan-evpn':  VXLAN based EVPNs [RFC8365].

      The type is used as a condition for the presence of some data
      nodes in the L2NM.

   'vpn-service-topology':  Indicates the network topology for the
      service: hub-spoke, any-to-any, or custom.

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   'bgp-ad-enabled':  Controls whether BGP auto-discovery is enabled.
      If so, additional data nodes are included (Section 7.5.1).

   'signaling-type':  Indicates the signaling that is used for setting
      pseudowires.  Signaling type values are taken from
      [I-D.ietf-opsawg-vpn-common].  The following signaling options are
      supported:

      'bgp-signaling':  The L2NM supports two flavors of BGP-signaled
         L2VPNs:

         'l2vpn-bgp':  The service is a Multipoint VPLS that uses a BGP
            control plane as described in [RFC4761] and [RFC6624].

         'evpn-bgp':  The service is a Multipoint VPLS that uses also a
            BGP control plane, but also includes the additional EVPN
            features and related parameters [RFC7432] and [RFC7209].

      'ldp-signaling':  A Multipoint VPLS that uses a mesh of LDP-
         signaled Pseudowires [RFC6074].

      l2tp-signaling':  The L2NM uses L2TP-signaled Pseudowires as
         described in [RFC6074].

      Table 1 summarizes the allowed signaling types for each VPN
      service type ('vpn-type').  See Section 7.5.2 for more details.

   'global-parameters-profiles':  Defines reusable parameters for the
      same L2VPN service.

      More details are provided in Section 7.4.

   'underlay-transport':  Describes the preference for the transport
      technology to carry the traffic of the VPN service.  This
      preference is especially useful in networks with multiple domains
      and Network-to-Network Interface (NNI) types.  The underlay
      transport can be expressed as an abstract transport instance
      (e.g., an identifier of a VPN+ instance, a virtual network
      identifier, or a network slice name) or as an ordered list of the
      actual protocols to be enabled in the network.

      A rich set of protocol identifiers that can be used to refer to an
      underlay transport (or how such an underlay is set up) are defined
      in [I-D.ietf-opsawg-vpn-common].

   'status':  Is used to track the service status of a given VPN

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      service.  Both operational and administrative status are
      maintained together with a timestamp.  For example, a service can
      be created, but not put into effect.

      Administrative and operational status can be used as a trigger to
      detect service anomalies.  For example, a service that is declared
      at the service layer as being active but still inactive at the
      network layer is an indication that network provision actions are
      needed to align the observed service status with the expected
      service status.

   'vpn-node':  Is an abstraction that represents a set of policies
      applied to a network node and that belong to a single 'vpn-
      service'.  An L2VPN service is typically built by adding instances
      of 'vpn-node' to the 'vpn-nodes' container.

      A 'vpn-node' contains 'vpn-network-accesses', which are the
      interfaces attached to the VPN by which the customer traffic is
      received.  Therefore, the customer sites are connected to the
      'vpn-network-accesses'.

      Note that, as this is a network data model, the information about
      customers sites is not required in the model.  Such information is
      rather relevant in the L2SM.  Whether that information is included
      in the L2NM, e.g., to populate the various 'description' data node
      is implementation-specific.

      More details are provided in Section 7.5.

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              +============+================================+
              | VPN Type   | Signaling Options              |
              +============+================================+
              | vpls       | l2tp-signaling, ldp-signaling, |
              |            | bgp-signaling (l2vpn-bgp)      |
              +------------+--------------------------------+
              | vpws       | l2tp-signaling, ldp-signaling, |
              |            | bgp-signaling (l2vpn-bgp)      |
              +------------+--------------------------------+
              | vpws-evpn  | bgp-signaling (evpn-bgp)       |
              +------------+--------------------------------+
              | pbb-evpn   | bgp-signaling (evpn-bgp)       |
              +------------+--------------------------------+
              | mpls-evpn  | bgp-signaling (evpn-bgp)       |
              +------------+--------------------------------+
              | vxlan-evpn | bgp-signaling (evpn-bgp)       |
              +------------+--------------------------------+

                  Table 1: Valid Signaling Options per VPN
                                Service Type

7.4.  Global Parameters Profiles

   The 'global-parameters-profile' defines reusable parameters for the
   same L2VPN service instance ('vpn-service').  Global parameters
   profile are defined at the VPN service level and then called at the
   VPN node and VPN network access levels.  Each VPN instance profile is
   identified by 'profile-id'.  Some of the data nodes can be adjusted
   at the VPN node or VPN network access levels.  These adjusted values
   take precedence over the global ones.  The subtree of 'global-
   parameters-profile' is depicted in Figure 7.

         ...
         +--rw vpn-services
            +--rw vpn-service* [vpn-id]
               ...
               +--rw global-parameters-profiles
               |  +--rw global-parameters-profile* [profile-id]
               |     +--rw profile-id                  string
               |     +--rw (rd-choice)?
               |     |  +--:(directly-assigned)
               |     |  |  +--rw rd?
               |     |  |          rt-types:route-distinguisher
               |     |  +--:(directly-assigned-suffix)
               |     |  |  +--rw rd-suffix?            uint16
               |     |  +--:(auto-assigned)
               |     |  |  +--rw rd-auto
               |     |  |     +--rw (auto-mode)?

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               |     |  |     |  +--:(from-pool)
               |     |  |     |  |  +--rw rd-pool-name?   string
               |     |  |     |  +--:(full-auto)
               |     |  |     |     +--rw auto?           empty
               |     |  |     +--ro auto-assigned-rd?
               |     |  |             rt-types:route-distinguisher
               |     |  +--:(auto-assigned-suffix)
               |     |  |  +--rw rd-auto-suffix
               |     |  |     +--rw (auto-mode)?
               |     |  |     |  +--:(from-pool)
               |     |  |     |  |  +--rw rd-pool-name?        string
               |     |  |     |  +--:(full-auto)
               |     |  |     |     +--rw auto?                empty
               |     |  |     +--ro auto-assigned-rd-suffix?   uint16
               |     |  +--:(no-rd)
               |     |     +--rw no-rd?                empty
               |     +--rw vpn-target* [id]
               |     |  +--rw id                  uint8
               |     |  +--rw route-targets* [route-target]
               |     |  |  +--rw route-target    rt-types:route-target
               |     |  +--rw route-target-type
               |     |          rt-types:route-target-type
               |     +--rw vpn-policies
               |     |  +--rw import-policy?   string
               |     |  +--rw export-policy?   string
               |     +--rw local-autonomous-system?    inet:as-number
               |     +--rw svc-mtu?                    uint32
               |     +--rw ce-vlan-preservation?       boolean
               |     +--rw ce-vlan-cos-preservation?   boolean
               |     +--rw control-word-negotiation?   boolean
               |     +--rw mac-policies
               |     |  +--rw mac-addr-limit
               |     |  |  +--rw mac-num-limit?   uint16
               |     |  |  +--rw time-interval?   uint32
               |     |  |  +--rw action?          identityref
               |     |  +--rw mac-loop-prevention
               |     |     +--rw window?            uint32
               |     |     +--rw frequency?         uint32
               |     |     +--rw retry-timer?       uint32
               |     |     +--rw protection-type?   identityref
               |     +--rw multicast-like {vpn-common:multicast}?
               |        +--rw enabled?                 boolean
               |        +--rw customer-tree-flavors
               |           +--rw tree-flavor*   identityref
                        ...

                Figure 7: Global Parameters Profiles Subtree

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   The description of the global parameters profile is as follows:

   'profile-id':  Uniquely identifies a global parameter profile in the
      context of an L2VPN service.

   'rd':  As defined in [I-D.ietf-opsawg-vpn-common], these RD
      assignment modes are supported: direct assignment, automatic
      assignment from a given pool, automatic assignment, and no
      assignment.  For illustration purposes, the following modes can be
      used in the deployment cases:

      'directly-assigned':  The VPN service provider (service
         orchestrator) assigns explicitly RDs.

      'full-auto':  The network controller auto-assigns RDs.

      'no-rd':  The VPN service provider (service orchestrator)
         explicitly wants no RD to be assigned.

      Also, the module accommodates deployments where only the Assigned
      Number subfield of RDs is assigned from a pool while the
      Administrator subfield is set to, e.g., the Router ID that is
      assigned to a VPN node.  The module supports these modes for
      managing the Assigned Number subfield: explicit assignment, auto-
      assignment from a pool, and full auto-assignment.

   'vpn-targets':  Specifies RT import/export rules for the VPN service.

   'local-autonomous-system':  Indicates the Autonomous System Number
      (ASN) that is configured for the VPN node.  The ASN can be used to
      auto-derive some other attributes such as RDs or Ethernet Segment
      Identifiers (ESIs).

   'svc-mtu':  Is the service MTU for an L2VPN service.  It is also
      known as the maximum transmission unit or maximum frame size.
      When a frame is larger than the MTU, it is fragmented to
      accommodate the MTU of the network.

   'ce-vlan-preservation':  Is set to preserve the CE-VLAN ID from
      ingress to egress, i.e., CE-VLAN tag of the egress frame are
      identical to those of the ingress frame that yielded this egress
      service frame.  If All-to-One bundling within a site is enabled,
      then preservation applies to all ingress service frames.  If All-
      to-One bundling is disabled, then preservation applies to tagged
      Ingress service frames having CE-VLAN ID 1 through 4094.

   'ce-vlan-cos-preservation':  Controls the CE VLAN CoS preservation.

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      When set, PCP bits in the CE-VLAN tag of the egress frame are
      identical to those of the ingress frame that yielded this egress
      service frame.

   'control-word-negotiation':  Controls whether control-word
      negotiation is enabled (if set to true) or not (if set to false).
      Refer to Section 7 of [RFC8077] for more details.

   'mac-policies':  Includes a set of MAC policies that apply to the
      service:

      'mac-addr-limit':  Is a container of MAC address limit
         configuration.  It includes the following data nodes:

         'mac-num-limit':  Maximum number of MAC addresses learned from
            the customer for a single service instance.

         'time-interval':  The aging time of the mac address.

         'action':  Specifies the action when the upper limit is
            exceeded: drop the packet, flood the packet, or simply send
            a warning log message.

      'mac-loop-prevention':  Container for MAC loop prevention.

         'window':  The timer when a MAC mobility event is detected.

         'frequency':  The number of times to detect MAC duplication,
            where a 'duplicate MAC address' situation has occurred and
            the duplicate MAC address has been added to a list of
            duplicate MAC addresses.

         'retry-timer':  The retry timer.  When the retry timer expires,
            the duplicate MAC address will be flushed from the MAC-VRF.

         'protection-type':  It defines the protection type

   'multicast-like':  Controls whether multicast is allowed in the
      service.

7.5.  VPN Nodes

   The 'vpn-node' is an abstraction that represents a set of policies/
   configurations applied to a network node and that belong to a single
   'vpn-service'.  A 'vpn-node' contains 'vpn-network-accesses', which
   are the interfaces involved in the creation of the VPN.  The customer
   sites are connected to the 'vpn-network-accesses'.

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      +--rw l2vpn-ntw
         +--rw vpn-profiles
         |  ...
         +--rw vpn-services
            +--rw vpn-service* [vpn-id]
               ...
               +--rw vpn-nodes
                  +--rw vpn-node* [vpn-node-id]
                     +--rw vpn-node-id            vpn-common:vpn-id
                     +--rw description?           string
                     +--rw ne-id?                 string
                     +--rw role?                  identityref
                     +--rw router-id?             rt-types:router-id
                     +--rw active-global-parameters-profiles
                     |  +--rw global-parameters-profile* [profile-id]
                     |     +--rw profile-id                  leafref
                     |     +--rw local-autonomous-system?
                     |     |       inet:as-number
                     |     +--rw svc-mtu?                    uint32
                     |     +--rw ce-vlan-preservation?       boolean
                     |     +--rw ce-vlan-cos-preservation?   boolean
                     |     +--rw control-word-negotiation?   boolean
                     |     +--rw mac-policies
                     |     |  +--rw mac-addr-limit
                     |     |  |  +--rw mac-num-limit?   uint16
                     |     |  |  +--rw time-interval?   uint32
                     |     |  |  +--rw action?          identityref
                     |     |  +--rw mac-loop-prevention
                     |     |     +--rw window?            uint32
                     |     |     +--rw frequency?         uint32
                     |     |     +--rw retry-timer?       uint32
                     |     |     +--rw protection-type?   identityref
                     |     +--rw multicast-like {vpn-common:multicast}?
                     |        +--rw enabled?                 boolean
                     |        +--rw customer-tree-flavors
                     |           +--rw tree-flavor*   identityref
                     +--rw status
                     |  ...
                     +--rw bgp-auto-discovery
                     |  ...
                     +--rw signaling-option
                     |  ...
                     +--rw vpn-network-accesses
                        ...

                        Figure 8: VPN Nodes Subtree

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   In reference to the subtree shown in Figure 8, the description of VPN
   node data nodes is as follows:

   'vpn-node-id':  Is an identifier that uniquely identifies a node that
      enables a VPN network access.

   'description':  Provides a textual description of the VPN node.

   'ne-id':  Includes a unique identifier of the network element where
      the VPN node is deployed.

   'router-id':  Indicates a 32-bit number that is used to uniquely
      identify a router within an Autonomous System (AS).

   'active-global-parameters-profiles':  Lists the set of active global
      VPN parameters profiles for this VPN node.  Concretely, one or
      more global profiles that are defined at the VPN service level can
      be activated at the VPN node level; each of these profiles is
      uniquely identified by means of 'profile-id'.  The structure of
      'active-global-parameters-profiles' uses the same data nodes as
      Section 7.4 except RD and RT related data nodes.

      Values defined in 'active-global-parameters-profiles' overrides
      the ones defined in the VPN service level.

   'signaling-option':  See Section 7.5.2.

   'status':  Tracks the status of a node involved in a VPN service.
      Both operational and administrative status are maintained.  A
      mismatch between the administrative status vs. the operational
      status can be used as a trigger to detect anomalies.

   'vpn-network-accesses':  Represents the point to which sites are
      connected.

      Note that, unlike in L2SM, the L2NM does not need to model the
      customer site, only the points where the traffic from the site are
      received (i.e., the PE side of PE-CE connections).  Hence, the VPN
      network access contains the connectivity information between the
      provider's network and the customer premises.  The VPN profiles
      ('vpn-profiles') have a set of routing policies that can be
      applied during the service creation.

      See Section 7.6 for more details.

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7.5.1.  BGP Auto-Discovery

   'bgp-auto-discovery' container (Figure 9) includes the required
   information for the activation of BGP auto-discovery
   [RFC4761][RFC6624].

     +--rw l2vpn-ntw
        +--rw vpn-profiles
        |  ...
        +--rw vpn-services
           +--rw vpn-service* [vpn-id]
              ...
              +--rw vpn-nodes
                 +--rw vpn-node* [vpn-node-id]
                    ...
                    +--rw bgp-auto-discovery
                    |  +--rw (bgp-type)?
                    |  |  +--:(l2vpn-bgp)
                    |  |  |  +--rw vpn-id?
                    |  |  |          vpn-common:vpn-id
                    |  |  +--:(evpn-bgp)
                    |  |     +--rw evpn-type?           leafref
                    |  |     +--rw auto-rt-enable?      boolean
                    |  |     +--ro auto-route-target?
                    |  |             rt-types:route-target
                    |  +--rw (rd-choice)?
                    |  |  +--:(directly-assigned)
                    |  |  |  +--rw rd?
                    |  |  |          rt-types:route-distinguisher
                    |  |  +--:(directly-assigned-suffix)
                    |  |  |  +--rw rd-suffix?           uint16
                    |  |  +--:(auto-assigned)
                    |  |  |  +--rw rd-auto
                    |  |  |     +--rw (auto-mode)?
                    |  |  |     |  +--:(from-pool)
                    |  |  |     |  |  +--rw rd-pool-name?   string
                    |  |  |     |  +--:(full-auto)
                    |  |  |     |     +--rw auto?           empty
                    |  |  |     +--ro auto-assigned-rd?
                    |  |  |             rt-types:route-distinguisher
                    |  |  +--:(auto-assigned-suffix)
                    |  |  |  +--rw rd-auto-suffix
                    |  |  |     +--rw (auto-mode)?
                    |  |  |     |  +--:(from-pool)
                    |  |  |     |  |  +--rw rd-pool-name?        string
                    |  |  |     |  +--:(full-auto)
                    |  |  |     |     +--rw auto?                empty
                    |  |  |     +--ro auto-assigned-rd-suffix?   uint16

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                    |  |  +--:(no-rd)
                    |  |     +--rw no-rd?               empty
                    |  +--rw vpn-target* [id]
                    |  |  +--rw id                  uint8
                    |  |  +--rw route-targets* [route-target]
                    |  |  |  +--rw route-target    rt-types:route-target
                    |  |  +--rw route-target-type
                    |  |          rt-types:route-target-type
                    |  +--rw vpn-policies
                    |     +--rw import-policy?   string
                    |     +--rw export-policy?   string
                    +--rw signaling-option
                    |  ...
                    +--rw vpn-network-accesses
                       ...

                    Figure 9: BGP Auto-Discovery Subtree

   As discussed in Section 1 of [RFC6624], all of BGP-based methods
   include the notion of a VPN identifier that serves to unify
   components of a given VPN and the concept of auto-discovery; hence
   the support of the data node 'vpn-id'.

   For the particular case of EVPN, the L2NM supports RT auto-derivation
   based on the Ethernet Tag ID specified in Section 7.10.1 of
   [RFC7432].  A VPN service provider can enable/disable this
   functionality by means of 'auto-rt-enable'.  The assigned RT can be
   retrieved using 'auto-route-target'.

   For all BGP-based L2VPN flavors, other data nodes such as RD and RT
   are used.  These data nodes have the same structure as the one
   discussed in Section 7.4.

7.5.2.  Signaling Options

   The 'signaling-option' container (Figure 10) defines a set of data
   nodes for a given signaling protocol that is used for an L2VPN
   service.  As discussed in Section 7.3, several signaling options to
   exchange membership information between PEs of an L2VPN are
   supported.  The signaling type to be used for an L2VPN service is
   controlled at the VPN service level by means of 'signaling-type'.

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                 ...
                 +--rw vpn-nodes
                    +--rw vpn-node* [vpn-node-id]
                    ...
                    +--rw signaling-option
                    |  +--rw advertise-mtu?        boolean
                    |  +--rw mtu-allow-mismatch?   boolean
                    |  +--rw signaling-type?       leafref
                    |  +--rw (signaling-option)?
                    |     +--:(bgp)
                    |     |  ...
                    |     +--:(ldp-or-l2tp)
                    |           +--rw (ldp-or-l2tp)?
                    |              +--:(ldp)
                    |              |  ...
                    |              +--:(l2tp)
                    |                 ...

                Figure 10: Signaling Option Overall Subtree

   The following signaling data nodes are supported:

   'advertise-mtu':  Controls whether MTU is advertised when setting a
      PW (e.g., Section 4.3 of [RFC4667], Section 5.1 of [RFC6624], or
      Section 6.1 of [RFC4762]).

   'mtu-allow-mismatch':  When set to true, it allows MTU mismatch for a
      PW (see, e.g., Section 4.3 of [RFC4667]).

   'signaling-type':  Indicates the signaling type.  This type inherits
      the value of 'signaling-type' defined at the service level
      (Section 7.3).

   'bgp':  Is provided when BGP is used for L2VPN signaling.  Refer to
      Section 7.5.2.1 for more details.

   'ldp':  The model supports the configuration of the parameters that
      are discussed in Section 6 of [RFC4762].  Refer to Section 7.5.2.2
      for more details.

   'l2tp':  The model supports the configuration of the parameters that
      are discussed in Section 4 of [RFC4667].  Refer to Section 7.5.2.3
      for more details.

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7.5.2.1.  BGP

   The structure of the BGP-related data nodes is provided in Figure 11.

         ...
         |  +--rw (signaling-option)?
         |     ...
         |     +--:(bgp)
         |     |  +--rw (bgp-type)?
         |     |     +--:(l2vpn-bgp)
         |     |     |  +--rw ce-id?        uint16
         |     |     |  +--rw ce-range?     uint16
         |     |     |  +--rw pw-encapsulation-type?
         |     |     |  |       identityref
         |     |     |  +--rw vpls-instance
         |     |     |     +--rw vpls-edge-id?         uint16
         |     |     |     +--rw vpls-edge-id-range?   uint16
         |     |     +--:(evpn-bgp)
         |     |        +--rw evpn-type?                leafref
         |     |        +--rw service-interface-type?
         |     |        |       identityref
         |     |        +--rw evpn-policies
         |     |           +--rw mac-learning-mode?
         |     |           |       identityref
         |     |           +--rw ingress-replication?
         |     |           |       boolean
         |     |           +--rw p2mp-replication?
         |     |           |       boolean
         |     |           +--rw arp-proxy {vpn-common:ipv4}?
         |     |           |  +--rw enable?           boolean
         |     |           |  +--rw arp-suppression?
         |     |           |  |       boolean
         |     |           |  +--rw ip-mobility-threshold?
         |     |           |  |       uint16
         |     |           |  +--rw duplicate-ip-detection-interval?
         |     |           |          uint16
         |     |           +--rw nd-proxy {vpn-common:ipv6}?
         |     |           |  +--rw enable?          boolean
         |     |           |  +--rw nd-suppression?
         |     |           |  |       boolean
         |     |           |  +--rw ip-mobility-threshold?
         |     |           |  |       uint16
         |     |           |  +--rw duplicate-ip-detection-interval?
         |     |           |          uint16
         |     |           +--rw underlay-multicast?
         |     |           |       boolean
         |     |           +--rw flood-unknown-unicast-supression?
         |     |           |       boolean

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         |     |           +--rw vpws-vlan-aware?        boolean
         |     |           +--rw bum-management
         |     |           |  +--rw discard-broadcast?
         |     |           |  |       boolean
         |     |           |  +--rw discard-unknown-multicast?
         |     |           |  |       boolean
         |     |           |  +--rw discard-unknown-unicast?
         |     |           |          boolean
         |     |           +--rw pbb
         |     |              +--rw backbone-src-mac?
         |     |                      yang:mac-address
         |     +--:(ldp-or-l2tp)
         |        ...

                 Figure 11: Signaling Option Subtree (BGP)

   As discussed in Section 2.2.2 of [RFC6624], a CE ID ('ce-id')
   identifying the CE within the VPN must be provided.  Remote CEs that
   are entitled to connect to the same VPN should fit with the CE range
   ('ce-range') as discussed in Section 2.2.3 of [RFC6624].  'pw-
   encapsulation-type' is used to control the PW encapsulation type
   (Section 3 of [RFC6624]).  The value of the 'pw-encapsulation-type'
   are taken from the IANA-maintained "iana-bgp-l2-encaps" module.

   For the specific case of VPLS, the VPLS Edge ID (VE ID, 'vpls-edge-
   id') and a VE ID range ('vpls-edge-id-range') are provided as per
   Section 3.2 of [RFC4761].

   For EVPN-related L2VPNs, 'service-interface-type' indicates whether
   this is VLAN-based, VLAN bundle, or VLAN-aware bundle service
   interface (Section 6 of [RFC7432]).  Moreover, a set of policies can
   be provided such as MAC address learning mode (Section 9 of
   [RFC7432]), ingress replication (Section 12.1 of [RFC7432]), Address
   Resolution Protocol (ARP) and Nighbor Discovery (ND) proxy
   (Section 10 of [RFC7432]), processing of Broadcast, unknown unicast,
   or multicast (BUM) (Section 12 of [RFC7432]), etc.

7.5.2.2.  LDP

   The model supports the configuration of the parameters that are
   discussed in Section 6 of [RFC4762].  Such parameters include a an
   Attachment Group Identifier (AGI) (a.k.a., VPLS-id), a Source
   Attachment Individual Identifier (SAII), a list of peers that are
   associated with a Target Attachment Individual Identifier (TAII), a
   PW type, and a PW description, (Figure 12).  Unlike BGP, only
   Ethernet and Ethernet tagged mode are supported.  The AGI, SAII, and
   TAII are encoded following the types defined in Section 3.4 of
   [RFC4446].

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             ...
             |  +--rw (signaling-option)?
             |     ...
             |     +--:(bgp)
             |     |  ...
             |     +--:(ldp-or-l2tp)
             |        +--rw ldp-or-l2tp
             |           +--rw agi?
             |           |       rt-types:route-distinguisher
             |           +--rw saii?                      uint32
             |           +--rw remote-targets* [taii]
             |           |  +--rw taii         uint32
             |           |  +--rw peer-addr    inet:ip-address
             |           +--rw (ldp-or-l2tp)?
             |              +--:(ldp)
             |              |  +--rw t-ldp-pw-type?
             |              |  |       identityref
             |              |  +--rw pw-type?       identityref
             |              |  +--rw pw-description?      string
             |              |  +--rw mac-addr-withdraw?   boolean
             |              |  +--rw pw-peer-list*
             |              |  |       [peer-addr vc-id]
             |              |  |  +--rw peer-addr
             |              |  |  |       inet:ip-address
             |              |  |  +--rw vc-id   string
             |              |  |  +--rw pw-priority?   uint32
             |              |  +--rw qinq
             |              |     +--rw s-tag    uint32
             |              |     +--rw c-tag    uint32
             |              +--:(l2tp)
             |                 +--rw router-id?
             |                 |       rt-types:router-id
             |                 +--rw pseudowire-type?
             |                         identityref
             ...

                 Figure 12: Signaling Option Subtree (LDP)

7.5.2.3.  L2TP

   The model supports the configuration of the parameters that are
   discussed in Section 4 of [RFC4667].  Such parameters include a
   router-id that is used to uniquely identify a PE, a PW type, an AGI,
   an SAII, and a list of peers that are associated with a TAII
   (Figure 13).  The PW type ('pseudowire-type') value is taken from the
   IANA-maintained "iana-pseudowire-types" module.

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             ...
             |  +--rw (signaling-option)?
             |     ...
             |     +--:(bgp)
             |     |  ...
             |     +--:(ldp-or-l2tp)
             |        +--rw ldp-or-l2tp
             |           +--rw agi?
             |           |       rt-types:route-distinguisher
             |           +--rw saii?                      uint32
             |           +--rw remote-target* [peer-addr taii]
             |           |  +--rw peer-addr    inet:ip-address
             |           |  +--rw taii         uint32
             |           +--rw (ldp-or-l2tp)?
             |              +--:(ldp)
             |              |  ...
             |              +--:(l2tp)
             |                 +--rw router-id?
             |                 |       rt-types:router-id
             |                 +--rw pseudowire-type?
             |                         identityref
             ...

                 Figure 13: Signaling Option Subtree (L2TP)

7.6.  VPN Network Accesses

   A 'vpn-network-access' (Figure 14) represents an entry point to a VPN
   service . In other words, this container encloses the parameters that
   describe the access information for the traffic that belongs to a
   particular L2VPN.  As such, every 'vpn-network-access' MUST belong to
   one and only one 'vpn-node'.

   A 'vpn-network-access' includes information such as the connection on
   which the access is defined , the specific layer 2 service
   requirements, etc.

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           ...
           +--rw vpn-nodes
              +--rw vpn-node* [vpn-node-id]
                 ...
                 +--rw vpn-network-accesses
                    +--rw vpn-network-access* [id]
                       +--rw id                        vpn-common:vpn-id
                       +--rw description?              string
                       +--rw interface-id?             string
                       +--rw global-parameters-profile?   leafref
                       +--rw status
                       |  ...
                       +--rw connection
                       |  ...
                       +--rw vpws-service-instance
                       |  ...
                       +--rw group* [group-id]
                       |  +--rw group-id                       string
                       |  +--rw precedence?
                       |  |       identityref
                       |  +--rw ethernet-segment-identifier?   string
                       +--rw ethernet-service-oam
                       |  ...
                       +--rw service
                          ...

                Figure 14: VPN Network Access Subtree

   The VPN network access is comprised of:

   'id':  Includes an identifier of the VPN network access.

   'description':  Includes a textual description of the VPN network
      access.

   'port-id':  Indicates the port on which the VPN network access is
      bound.

   ' global-parameters-profile':  Provides a pointer to an active
      'global-parameters-profile' at the VPN node level.  Referencing an
      active 'global-parameters-profile' implies that all associated
      data nodes will be inherited by the VPN network access.  However,
      some of the inherited data nodes (e.g., ACL policies) can be
      overridden at the VPN network access level.  In such case,
      adjusted values take precedence over inherited ones.

   'status':  Indicates the administrative and operational status of the
      service.

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   'connection':  Represents and groups the set of Layer 2 connectivity
      from where the traffic of the L2VPN in a particular VPN Network
      access is coming.  See Section 7.6.1.

   'vpws-service-instance':  Includes a set of data nodes that are
      required for the configuration of a VPWS-EVPN [RFC8214].  See
      Section 7.6.2.

   'group':  Is used for grouping VPN network accesses by assigning the
      same identifier to these accesses.  The precedence attribute is
      used to differentiate the primary and secondary accesses for a
      service with multiple accesses.  An example to illustrate the use
      of this container for redundancy purposes is provided in
      Appendix A.6.  This container is also used to identify the link of
      an ES by allocating the same ESI.  An example to illustrate this
      functionality is provided in Appendices A.4 and A.5.

   'ethernet-service-oam':  Carries information about the service OAM.
      See Section 7.6.3.

   'service':  Specifies the service parameters (e.g., QoS, multicast)
      to apply for a given VPN network access.  See Section 7.6.4.

7.6.1.  Connection

   The 'connection' container (Figure 15) is used to configure the
   relevant properties of the interface to which the L2VPN instance is
   attached to (e.g., encapsulation type, LAG interfaces, split-
   horizon).  The L2NM supports tag manipulation operations (e.g., tag
   rewrite).

   Note that the 'connection' container does not include the physical-
   specific configuration as this is assumed to be directly handled
   using device modules (e.g., interfaces module).  Moreover, this
   design is also meant to avoid manipulated global parameters at the
   service level and lower the risk of impacting other services sharing
   the same physical interface.

   Some consistency checks should be ensured by implementations
   (typically, network controllers) for LAG interface as the same
   information (e.g., LACP system-id) should be provided to the involved
   nodes.

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              ...
              +--rw vpn-nodes
                 +--rw vpn-node* [vpn-node-id]
                    ...
                    +--rw vpn-network-accesses
                       +--rw vpn-network-access* [id]
                          ...
                          +--rw connection
                          |  +--rw l2-termination-point?
                          |  |       string
                          |  +--rw local-bridge-reference?
                          |  |       string
                          |  +--rw bearer-reference?         string
                          |  |       {vpn-common:bearer-reference}?
                          |  +--rw encapsulation
                          |  |  +--rw encap-type?            identityref
                          |  |  +--rw dot1q
                          |  |  |  +--rw tag-type?   identityref
                          |  |  |  +--rw cvlan-id?   uint16
                          |  |  |  +--rw rewrite
                          |  |  |     +--rw (tag-choice)?
                          |  |  |     |  +--:(pop)
                          |  |  |     |  |  +--rw pop?
                          |  |  |     |  |          enumeration
                          |  |  |     |  +--:(push)
                          |  |  |     |  |  +--rw push?        empty
                          |  |  |     |  +--:(translate)
                          |  |  |     |     +--rw translate?
                          |  |  |     |             enumeration
                          |  |  |     +--rw cvlan-id?          uint16
                          |  |  |     +--rw mode?         enumeration
                          |  |  +--rw priority-tagged
                          |  |  |  +--rw tag-type?   identityref
                          |  |  +--rw qinq
                          |  |     +--rw tag-type?   identityref
                          |  |     +--rw svlan-id    uint16
                          |  |     +--rw cvlan-id    uint16
                          |  +--rw lag-interface
                          |     |    {vpn-common:lag-interface}?
                          |     +--rw lag-interface-id?   string
                          |     +--rw lacp
                          |     |  +--rw lacp-state?         boolean
                          |     |  +--rw mode?               identityref
                          |     |  +--rw speed?              uint32
                          |     |  +--rw mini-link-num?      uint32
                          |     |  +--rw system-id?
                          |     |  |       yang:mac-address
                          |     |  +--rw admin-key?          uint16

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                          |     |  +--rw system-priority?    uint16
                          |     |  +--rw member-link-list
                          |     |  |  +--rw member-link* [name]
                          |     |  |     +--rw name         string
                          |     |  |     +--rw port-speed?  uint32
                          |     |  |     +--rw mode?   identityref
                          |     |  |     +--rw link-mtu?    uint32
                          |     |  |     +--rw oam-802.3ah-link
                          |     |  |        |    {oam-3ah}?
                          |     |  |        +--rw enable?   boolean
                          |     |  +--rw flow-control?       string
                          |     |  +--rw lldp?               boolean
                          |     +--rw split-horizon
                          |        +--rw group-name?   string
                          ...

                       Figure 15: Connection Subtree

7.6.2.  EVPN-VPWS Service Instance

   The 'vpws-service-instance' provides the local and remote VPWS
   Service Instance (VSI) [RFC8214].  This container is only present
   when the 'vpn-type' is VPWS-EVPN.  As shown in Figure 16, the VSIs
   can be configured by a VPN service provider or auto-generated.

   An example to illustrate the use of the L2NM to configure VPWS-EVPN
   instances is provided in Appendix A.4.

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              ...
              +--rw vpn-nodes
                 +--rw vpn-node* [vpn-node-id]
                    ...
                    +--rw vpn-network-accesses
                       +--rw vpn-network-access* [id]
                          ...
                          +--rw vpws-service-instance
                          |  +--rw (local-vsi-choice)?
                          |  |  +--:(directly-assigned)
                          |  |  |  +--rw local-vpws-service-instance?
                          |  |  |          uint32
                          |  |  +--:(auto-assigned)
                          |  |     +--rw local-vsi-auto
                          |  |        +--rw (auto-mode)?
                          |  |        |  +--:(from-pool)
                          |  |        |  |  +--rw vsi-pool-name?
                          |  |        |  |          string
                          |  |        |  +--:(full-auto)
                          |  |        |     +--rw auto?            empty
                          |  |        +--ro auto-local-vsi?
                          |  |                uint32
                          |  +--rw (remote-vsi-choice)?
                          |     +--:(directly-assigned)
                          |     |  +--rw remote-vpws-service-instance?
                          |     |          uint32
                          |     +--:(auto-assigned)
                          |        +--rw remote-vsi-auto
                          |           +--rw (auto-mode)?
                          |           |  +--:(from-pool)
                          |           |  |  +--rw vsi-pool-name?
                          |           |  |          string
                          |           |  +--:(full-auto)
                          |           |     +--rw auto?            empty
                          |           +--ro auto-remote-vsi?
                          |                   uint32
                          ...

               Figure 16: EVPN-VPWS Service Instance Subtree

7.6.3.  Ethernet OAM

   Ethernet OAM refers to both [IEEE-802-1ag] and [ITU-T-Y-1731].

   As shown in Figure 17, the L2NM inherits the same structure as in
   Section 5.3.2.2.6 of [RFC8466] for OAM matters.

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       +--rw l2vpn-ntw
          +--rw vpn-profiles
          |  ...
          +--rw vpn-services
             +--rw vpn-service* [vpn-id]
                ...
                +--rw vpn-nodes
                   +--rw vpn-node* [vpn-node-id]
                      ...
                      +--rw vpn-network-accesses
                         +--rw vpn-network-access* [id]
                            ...
                            +--rw ethernet-service-oam
                            |  +--rw md-name?        string
                            |  +--rw md-level?       uint8
                            |  +--rw cfm-802.1-ag
                            |  |  +--rw n2-uni-c* [maid]
                            |  |  |  +--rw maid                string
                            |  |  |  +--rw mep-id?             uint32
                            |  |  |  +--rw mep-level?          uint32
                            |  |  |  +--rw mep-up-down?
                            |  |  |  |                   enumeration
                            |  |  |  +--rw remote-mep-id?      uint32
                            |  |  |  +--rw cos-for-cfm-pdus?   uint32
                            |  |  |  +--rw ccm-interval?       uint32
                            |  |  |  +--rw ccm-holdtime?       uint32
                            |  |  |  +--rw ccm-p-bits-pri?
                            |  |  |          ccm-priority-type
                            |  |  +--rw n2-uni-n* [maid]
                            |  |     +--rw maid                string
                            |  |     +--rw mep-id?             uint32
                            |  |     +--rw mep-level?          uint32
                            |  |     +--rw mep-up-down?
                            |  |     |                    enumeration
                            |  |     +--rw remote-mep-id?      uint32
                            |  |     +--rw cos-for-cfm-pdus?   uint32
                            |  |     +--rw ccm-interval?       uint32
                            |  |     +--rw ccm-holdtime?       uint32
                            |  |     +--rw ccm-p-bits-pri?
                            |  |             ccm-priority-type
                            |  +--rw y-1731* [maid]
                            |     +--rw maid               string
                            |     +--rw mep-id?            uint32
                            |     +--rw pm-type?           identityref
                            |     +--rw remote-mep-id?     uint32
                            |     +--rw message-period?    uint32
                            |     +--rw measurement-interval?   uint32
                            |     +--rw cos?        uint32

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                            |     +--rw loss-measurement?      boolean
                            |     +--rw synthethic-loss-measurement?
                            |     |       boolean
                            |     +--rw delay-measurement
                            |     |  +--rw enable-dm?   boolean
                            |     |  +--rw two-way?     boolean
                            |     +--rw frame-size?     uint32
                            |     +--rw session-type?   enumeration
                            ...

                           Figure 17: OAM Subtree

7.6.4.  Services

   The 'service' container (Figure 18) provides a set of service-
   specific configuration such as Quality of Service (QoS).

      +--rw l2vpn-ntw
         +--rw vpn-profiles
         |  ...
         +--rw vpn-services
            +--rw vpn-service* [vpn-id]
               ...
               +--rw vpn-nodes
                  +--rw vpn-node* [vpn-node-id]
                     ...
                     +--rw vpn-network-accesses
                        +--rw vpn-network-access* [id]
                           ...
                           +--rw service
                              +--rw mtu?            uint32
                              +--rw svc-inbound-bandwidth
                              |       {vpn-common:inbound-bw}?
                              |  ...
                              +--rw svc-outbound-bandwidth
                              |       {vpn-common:outbound-bw}?
                              |  ...
                              +--rw qos {vpn-common:qos}?
                              |  ...
                              +--rw mac-policies
                              |  ...
                              +--rw broadcast-unknown-unicast-multicast
                                 ...

                     Figure 18: Service Overall Subtree

   The description of the service data nodes is as follows:

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   'mtu':  Specifies the MTU for the VPN network access.

   'svc-inbound-bandwidth' and 'svc-outbound-bandwidth':  Specify the
      service bandwidth for the L2VPN service.  It can be represented
      using the Committed Information Rate (CIR), the Excess Information
      Rate (EIR), or the Peak Information Rate (PIR).  As shown in
      Figure 19, the structure of service bandwidth data nodes is
      inherited from the L2SM [RFC8466].  The following types, defined
      in [I-D.ietf-opsawg-vpn-common], can be used to indicate the
      bandwidth type:

      'bw-per-cos':  The bandwidth is per Class of Service (CoS).

      'bw-per-port':  The bandwidth is per VPN network access.

      'bw-per-site':  The bandwidth is to all VPN network accesses that
         belong to the same site.

      'bw-per-service':  The bandwidth is per L2VPN service.

      'svc-inbound-bandwidth' indicates the inbound bandwidth of the
      connection (i.e., download bandwidth from the service provider to
      the site).

      'svc-outbound-bandwidth' indicates the outbound bandwidth of the
      connection (i.e., upload bandwidth from the site to the service
      provider).

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                              +--rw service
                                 ...
                                 +--rw svc-inbound-bandwidth
                                 |       {vpn-common:inbound-bw}?
                                 |  +--rw inbound-bandwidth* [bw-type]
                                 |     +--rw bw-type   identityref
                                 |     +--rw cos-id?   uint8
                                 |     |       {vpn-common:qos}?
                                 |     +--rw cir?      uint64
                                 |     +--rw cbs?      uint64
                                 |     +--rw eir?      uint64
                                 |     +--rw ebs?      uint64
                                 |     +--rw pir?      uint64
                                 |     +--rw pbs?      uint64
                                 +--rw svc-outbound-bandwidth
                                 |       {vpn-common:outbound-bw}?
                                 |  +--rw outbound-bandwidth* [bw-type]
                                 |     +--rw bw-type   identityref
                                 |     +--rw cos-id?   uint8
                                 |     |       {vpn-common:qos}?
                                 |     +--rw cir?      uint64
                                 |     +--rw cbs?      uint64
                                 |     +--rw eir?      uint64
                                 |     +--rw ebs?      uint64
                                 |     +--rw pir?      uint64
                                 |     +--rw pbs?      uint64
                                 ...

                     Figure 19: Service Bandwidth Subtree

   'qos':  Is used to define a set of QoS policies to apply on a given
    VPN network access (Figure 20).  The QoS classification can be
    based on many criteria such as source MAC address, destination MAC
    address, etc.  See also Section 5.10.2.1 of [RFC8466].

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                           +--rw service
                              ...
                              +--rw qos {vpn-common:qos}?
                              |  +--rw qos-classification-policy
                              |  |  +--rw rule* [id]
                              |  |     +--rw id                string
                              |  |     +--rw (match-type)?
                              |  |     |  +--:(match-flow)
                              |  |     |  |  +--rw match-flow
                              |  |     |  |     +--rw dscp?   inet:dscp
                              |  |     |  |     +--rw dot1q?     uint16
                              |  |     |  |     +--rw pcp?       uint8
                              |  |     |  |     +--rw src-mac-address?
                              |  |     |  |     |       yang:mac-address
                              |  |     |  |     +--rw dst-mac-address?
                              |  |     |  |     |       yang:mac-address
                              |  |     |  |     +--rw color-type?
                              |  |     |  |     |       identityref
                              |  |     |  |     +--rw any?         empty
                              |  |     |  +--:(match-application)
                              |  |     |     +--rw match-application?
                              |  |     |             identityref
                              |  |     +--rw target-class-id?     string
                              |  +--rw qos-profile
                              |     +--rw qos-profile* [profile]
                              |        +--rw profile      leafref
                              |        +--rw direction?   identityref
                              ...

                          Figure 20: QoS Subtree

   'mac-policies':  Lists a set of MAC-related policies such as MAC
    ACLs.  An ACL can be based on source MAC address, source MAC
    address mask, destination MAC address , and destination MAC
    address mask.  A data frame that matches an ACL can be dropped,
    flooded, or trigger an alarm.  A rate-limit policy can be defined
    for handling frames that match an ACL entry with 'flood' action.

    When 'mac-loop-prevention' or 'mac-addr-limit' data nodes are
    provided, they take precedence over the one inlcuded in the
    'global-parameters-profile' at the VPN service or VPN node levels.

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                           +--rw service
                              ...
                              +--rw mac-policies
                              |  +--rw access-control-list* [name]
                              |  |  +--rw name                    string
                              |  |  +--rw src-mac-address*
                              |  |  |       yang:mac-address
                              |  |  +--rw src-mac-address-mask*
                              |  |  |       yang:mac-address
                              |  |  +--rw dst-mac-address*
                              |  |  |       yang:mac-address
                              |  |  +--rw dst-mac-address-mask*
                              |  |  |       yang:mac-address
                              |  |  +--rw action?          identityref
                              |  |  +--rw rate-limit?      decimal64
                              |  +--rw mac-loop-prevention
                              |  |  +--rw window?            uint32
                              |  |  +--rw frequency?         uint32
                              |  |  +--rw retry-timer?       uint32
                              |  |  +--rw protection-type?   identityref
                              |  +--rw mac-addr-limit
                              |     +--rw mac-num-limit?   uint16
                              |     +--rw time-interval?   uint32
                              |     +--rw action?          identityref
                              ...

                     Figure 21: MAC Policies Subtree

   'broadcast-unknown-unicast-multicast':  Defines the type of site in
   the customer multicast service topology: source, receiver, or
   both.  It is also used to define multicast group-to-port mappings.

                          +--rw service
                             ...
                             +--rw broadcast-unknown-unicast-multicast
                                +--rw multicast-site-type?
                                |       enumeration
                                +--rw multicast-gp-address-mapping* [id]
                                |  +--rw id                 uint16
                                |  +--rw vlan-id?           uint32
                                |  +--rw mac-gp-address?
                                |  |       yang:mac-address
                                |  +--rw port-lag-number?   uint32
                                +--rw bum-overall-rate?     uint32

                         Figure 22: BUM Subtree

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8.  YANG Modules

8.1.  IANA BGP Layer 2 Encapsulation Types

   The "iana-bgp-l2-encaps" YANG module (Section 8.1) is designed to
   echo the registry available at [IANA-BGP-L2].  Appendix B lists the
   initial values included in the "iana-bgp-l2-encaps" YANG module.

   <CODE BEGINS>
   file "iana-bgp-l2-encaps@2021-07-05.yang"
   module iana-bgp-l2-encaps {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:iana-bgp-l2-encaps";
     prefix iana-bgp-l2-encaps;

     organization
       "IANA";
     contact
       "Internet Assigned Numbers Authority

        Postal: ICANN
             12025 Waterfront Drive, Suite 300
             Los Angeles, CA  90094-2536
             United States of America
        Tel:    +1 310 301 5800
        <mailto:iana@iana.org>";
     description
       "This module contains a collection of YANG data types defined
        by IANA and used for referring to BGP layer 2 encapsulation
        types.

        Copyright (c) 2021 IETF Trust and the persons identified as
        authors of the code.  All rights reserved.

        Redistribution and use in source and binary forms, with or
        without modification, is permitted pursuant to, and subject
        to the license terms contained in, the Simplified BSD License
        set forth in Section 4.c of the IETF Trust's Legal Provisions
        Relating to IETF Documents
        (http://trustee.ietf.org/license-info).

        This version of this YANG module is part of RFC XXXX; see
        the RFC itself for full legal notices.";

     revision 2021-07-05 {
       description
         "First revision.";

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       reference
         "RFC XXXX: A Layer 2 VPN Network YANG Model.";
     }

     identity bgp-l2-encaps-type {
       description
         "Base BGP Layer 2 encapsulation type.";
       reference
         "RFC 6624: Layer 2 Virtual Private Networks Using BGP for
                    Auto-Discovery and Signaling";
     }

     identity frame-relay {
       base bgp-l2-encaps-type;
       description
         "Frame Relay.";
       reference
         "RFC 4446: IANA Allocations for Pseudowire Edge
                    to Edge Emulation (PWE3)";
     }

     identity atm-aal5 {
       base bgp-l2-encaps-type;
       description
         "ATM AAL5 SDU VCC transport.";
       reference
         "RFC 4446: IANA Allocations for Pseudowire Edge
                    to Edge Emulation (PWE3)";
     }

     identity atm-cell {
       base bgp-l2-encaps-type;
       description
         "ATM transparent cell transport";
       reference
         "RFC 4816: Pseudowire Emulation Edge-to-Edge (PWE3)
                    Asynchronous Transfer Mode (ATM) Transparent
                    Cell Transport Service";
     }

     identity ethernet-tagged-mode {
       base bgp-l2-encaps-type;
       description
         "Ethernet (VLAN) Tagged Mode.";
       reference
         "RFC 4448: Encapsulation Methods for Transport of Ethernet
                    over MPLS Networks";
     }

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     identity ethernet-raw-mode {
       base bgp-l2-encaps-type;
       description
         "Ethernet Raw Mode.";
       reference
         "RFC 4448: Encapsulation Methods for Transport of Ethernet
                    over MPLS Networks";
     }

     identity hdlc {
       base bgp-l2-encaps-type;
       description
         "Cisco HDLC.";
       reference
         "RFC 4618: Encapsulation Methods for Transport of
                    PPP/High-Level Data Link Control (HDLC)
                    over MPLS Networks";
     }

     identity ppp {
       base bgp-l2-encaps-type;
       description
         "PPP.";
       reference
         "RFC 4618: Encapsulation Methods for Transport of
                    PPP/High-Level Data Link Control (HDLC)
                    over MPLS Networks";
     }

     identity circuit-emulation {
       base bgp-l2-encaps-type;
       description
         "SONET/SDH Circuit Emulation Service.";
       reference
         "RFC 4842: Synchronous Optical Network/Synchronous Digital
                    Hierarchy (SONET/SDH) Circuit Emulation over Packet
                    (CEP)";
     }

     identity atm-to-vcc {
       base bgp-l2-encaps-type;
       description
         "ATM n-to-one VCC cell transport.";
       reference
         "RFC 4717: Encapsulation Methods for Transport of
                    Asynchronous Transfer Mode (ATM) over MPLS Networks";
     }

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     identity atm-to-vpc {
       base bgp-l2-encaps-type;
       description
         "ATM n-to-one VPC cell transport.";
       reference
         "RFC 4717: Encapsulation Methods for Transport of
                    Asynchronous Transfer Mode (ATM) over MPLS Networks";
     }

     identity layer-2-transport {
       base bgp-l2-encaps-type;
       description
         "IP Layer 2 Transport.";
       reference
         "RFC 3032: MPLS Label Stack Encoding";
     }

     identity fr-port-mode {
       base bgp-l2-encaps-type;
       description
         "Frame Relay Port mode.";
       reference
         "RFC 4619: Encapsulation Methods for Transport of Frame Relay over
                    Multiprotocol Label Switching (MPLS) Networks";
     }

     identity e1 {
       base bgp-l2-encaps-type;
       description
         "Structure-agnostic E1 over packet.";
       reference
         "RFC 4553: Structure-Agnostic Time Division Multiplexing (TDM)
                    over Packet (SAToP)";
     }

     identity t1 {
       base bgp-l2-encaps-type;
       description
         "Structure-agnostic T1 (DS1) over packet.";
       reference
         "RFC 4553: Structure-Agnostic Time Division Multiplexing (TDM)
                    over Packet (SAToP)";
     }

     identity vpls {
       base bgp-l2-encaps-type;
       description
         "VPLS.";

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       reference
         "RFC 4761: Virtual Private LAN Service (VPLS)
                    Using BGP for Auto-Discovery and Signaling";
     }

     identity t3 {
       base bgp-l2-encaps-type;
       description
         "Structure-agnostic T3 (DS3) over packet.";
       reference
         "RFC 4553: Structure-Agnostic Time Division Multiplexing (TDM)
                    over Packet (SAToP)";
     }

     identity structure-aware {
       base bgp-l2-encaps-type;
       description
         "Nx64kbit/s Basic Service using Structure-aware.";
       reference
         "RFC 5086: Structure-Aware Time Division Multiplexed (TDM)
                    Circuit Emulation Service over Packet Switched
                    Network (CESoPSN)";
     }

     identity dlci {
       base bgp-l2-encaps-type;
       description
         "Frame Relay DLCI.";
       reference
         "RFC 4619: Encapsulation Methods for Transport of Frame Relay over
                    Multiprotocol Label Switching (MPLS) Networks";
     }

     identity e3 {
       base bgp-l2-encaps-type;
       description
         "Structure-agnostic E3 over packet.";
       reference
         "RFC 4553: Structure-Agnostic Time Division Multiplexing (TDM)
                    over Packet (SAToP)";
     }

     identity ds1 {
       base bgp-l2-encaps-type;
       description
         "Octet-aligned payload for Structure-agnostic DS1 circuits.";
       reference
         "RFC 4553: Structure-Agnostic Time Division Multiplexing (TDM)

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                    over Packet (SAToP)";
     }

     identity cas {
       base bgp-l2-encaps-type;
       description
         "DS1 (ESF) Nx64kbit/s with CAS using Structure-aware.";
       reference
         "RFC 5086: Structure-Aware Time Division Multiplexed (TDM)
                    Circuit Emulation Service over Packet Switched
                    Network (CESoPSN)";
     }

     identity esf {
       base bgp-l2-encaps-type;
       description
         "DS1 (ESF) Nx64kbit/s with CAS using Structure-aware.";
       reference
         "RFC 5086: Structure-Aware Time Division Multiplexed (TDM)
                    Circuit Emulation Service over Packet Switched
                    Network (CESoPSN)";
     }

     identity sf {
       base bgp-l2-encaps-type;
       description
         "DS1 (SF) Nx64kbit/s with CAS using Structure-aware.";
       reference
         "RFC 5086: Structure-Aware Time Division Multiplexed (TDM)
                    Circuit Emulation Service over Packet Switched
                    Network (CESoPSN)";
     }
   }
   <CODE ENDS>

8.2.  IANA Encapsulation Types

   The initial version of the "iana-pseudowire-types" YANG module
   (Section 8.2) is designed to echo the registry available at
   [IANA-PW-Types]. . Appendix C lists the initial values included in
   the "iana-bgp-l2-encaps" YANG module.

   <CODE BEGINS>
   file "iana-pseudowire-types@2021-07-05.yang"
   module iana-pseudowire-types {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:iana-pseudowire-types";
     prefix iana-pw-types;

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     organization
       "IANA";
     contact
       "Internet Assigned Numbers Authority

        Postal: ICANN
             12025 Waterfront Drive, Suite 300
             Los Angeles, CA  90094-2536
             United States of America
        Tel:    +1 310 301 5800
        <mailto:iana@iana.org>";
     description
       "This module contains a collection of YANG data types defined
        by IANA and used for referring to Pseudowire Types.

        Copyright (c) 2021 IETF Trust and the persons identified as
        authors of the code.  All rights reserved.

        Redistribution and use in source and binary forms, with or
        without modification, is permitted pursuant to, and subject
        to the license terms contained in, the Simplified BSD License
        set forth in Section 4.c of the IETF Trust's Legal Provisions
        Relating to IETF Documents
        (http://trustee.ietf.org/license-info).

        This version of this YANG module is part of RFC XXXX; see
        the RFC itself for full legal notices.";

     revision 2021-07-05 {
       description
         "First revision.";
       reference
         "RFC XXXX: A Layer 2 VPN Network YANG Model.";
     }

     identity iana-pw-types {
       description
         "Base BGP Layer 2 encapsulation type.";
     }

     identity frame-relay {
       base iana-pw-types;
       description
         "Frame Relay.";
       reference
         "RFC 4619: Encapsulation Methods for Transport of Frame Relay
                    over Multiprotocol Label Switching (MPLS) Networks";
     }

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     identity atm-aal5 {
       base iana-pw-types;
       description
         "ATM AAL5 SDU VCC transport.";
     }

     identity atm-cell {
       base iana-pw-types;
       description
         "ATM transparent cell transport";
       reference
         "RFC 4717: Encapsulation Methods for Transport of
                    Asynchronous Transfer Mode (ATM) over MPLS
                    Networks";
     }

     identity ethernet-tagged-mode {
       base iana-pw-types;
       description
         "Ethernet (VLAN) Tagged Mode.";
       reference
         "RFC 4448: Encapsulation Methods for Transport of Ethernet
                    over MPLS Networks";
     }

     identity ethernet {
       base iana-pw-types;
       description
         "Ethernet.";
       reference
         "RFC 4448: Encapsulation Methods for Transport of Ethernet
                    over MPLS Networks";
     }

     identity hdlc {
       base iana-pw-types;
       description
         "Cisco HDLC.";
       reference
         "RFC 4618: Encapsulation Methods for Transport of
                    PPP/High-Level Data Link Control (HDLC)
                    over MPLS Networks";
     }

     identity ppp {
       base iana-pw-types;
       description
         "PPP.";

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       reference
         "RFC 4618: Encapsulation Methods for Transport of
                    PPP/High-Level Data Link Control (HDLC)
                    over MPLS Networks";
     }

     identity circuit-emulation-mpls {
       base iana-pw-types;
       description
         "SONET/SDH Circuit Emulation Service Over MPLS Encapsulation.";
       reference
         "RFC 5143: Synchronous Optical Network/Synchronous Digital
                    Hierarchy (SONET/SDH) Circuit Emulation Service over
                    MPLS (CEM) Encapsulation";
     }

     identity atm-to-vcc {
       base iana-pw-types;
       description
         "ATM n-to-one VCC cell transport.";
       reference
         "RFC 4717: Encapsulation Methods for Transport of
                    Asynchronous Transfer Mode (ATM) over MPLS Networks";
     }

     identity atm-to-vpc {
       base iana-pw-types;
       description
         "ATM n-to-one VPC cell transport.";
       reference
         "RFC 4717: Encapsulation Methods for Transport of
                    Asynchronous Transfer Mode (ATM) over MPLS Networks";
     }

     identity layer-2-transport {
       base iana-pw-types;
       description
         "IP Layer2 Transport.";
       reference
         "RFC 3032: MPLS Label Stack Encoding";
     }

     identity atm-one-to-one-vcc {
       base iana-pw-types;
       description
         "ATM one-to-one VCC Cell Mode.";
       reference
         "RFC 4717: Encapsulation Methods for Transport of

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                    Asynchronous Transfer Mode (ATM) over MPLS Networks";
     }

     identity atm-one-to-one-vpc {
       base iana-pw-types;
       description
         "ATM one-to-one VPC Cell Mode.";
       reference
         "RFC 4717: Encapsulation Methods for Transport of
                    Asynchronous Transfer Mode (ATM) over MPLS Networks";
     }

     identity atm-aal5-vcc {
       base iana-pw-types;
       description
         "ATM AAL5 PDU VCC transport.";
       reference
         "RFC 4717: Encapsulation Methods for Transport of
                    Asynchronous Transfer Mode (ATM) over MPLS Networks";
     }

     identity fr-port-mode {
       base iana-pw-types;
       description
         "Frame-Relay Port mode.";
       reference
         "RFC 4619: Encapsulation Methods for Transport of Frame Relay over
                    Multiprotocol Label Switching (MPLS) Networks";
     }

     identity circuit-emulation-packet {
       base iana-pw-types;
       description
         "SONET/SDH Circuit Emulation over Packet.";
       reference
         "RFC 4842: Synchronous Optical Network/Synchronous Digital
                    Hierarchy (SONET/SDH) Circuit Emulation over Packet
                    (CEP)";
     }

     identity e1 {
       base iana-pw-types;
       description
         "Structure-agnostic E1 over Packet.";
       reference
         "RFC 4553: Structure-Agnostic Time Division Multiplexing (TDM)
                    over Packet (SAToP)";
     }

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     identity t1 {
       base iana-pw-types;
       description
         "Structure-agnostic T1 (DS1) over Packet.";
       reference
         "RFC 4553: Structure-Agnostic Time Division Multiplexing (TDM)
                    over Packet (SAToP)";
     }

     identity e3 {
       base iana-pw-types;
       description
         "Structure-agnostic E3 over Packet.";
       reference
         "RFC 4553: Structure-Agnostic Time Division Multiplexing (TDM)
                    over Packet (SAToP)";
     }

     identity t3 {
       base iana-pw-types;
       description
         "Structure-agnostic T3 (DS3) over Packet.";
       reference
         "RFC 4553: Structure-Agnostic Time Division Multiplexing (TDM)
                    over Packet (SAToP)";
     }

     identity ces-over-psn {
       base iana-pw-types;
       description
         "CESoPSN basic mode.";
       reference
         "RFC 5086: Structure-Aware Time Division Multiplexed (TDM)
                    Circuit Emulation Service over Packet Switched Network
                    (CESoPSN)";
     }

     identity tdm-over-ip-aal1 {
       base iana-pw-types;
       description
         "TDMoIP AAL1 Mode.";
       reference
         "RFC 5087: Time Division Multiplexing over IP (TDMoIP)";
     }

     identity ces-over-psn-cas {
       base iana-pw-types;
       description

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         "CESoPSN TDM with CAS.";
       reference
         "RFC 5086: Structure-Aware Time Division Multiplexed (TDM)
                    Circuit Emulation Service over Packet Switched Network
                    (CESoPSN)";
     }

     identity tdm-over-ip-aal2 {
       base iana-pw-types;
       description
         "TDMoIP AAL2 Mode.";
       reference
         "RFC 5087: Time Division Multiplexing over IP (TDMoIP)";
     }

     identity dlci {
       base iana-pw-types;
       description
         "Frame Relay DLCI.";
       reference
         "RFC 4619: Encapsulation Methods for Transport of Frame Relay over
                    Multiprotocol Label Switching (MPLS) Networks";
     }

     identity rohc {
       base iana-pw-types;
       description
         "ROHC Transport Header-compressed Packets.";
       reference
         "RFC 5795: The RObust Header Compression (ROHC) Framework
          RFC 4901: Protocol Extensions for Header Compression over MPLS";
     }

     identity ecrtp {
       base iana-pw-types;
       description
         "ECRTP Transport Header-compressed Packets.";
       reference
         "RFC 3545: Enhanced Compressed RTP (CRTP) for Links with High
                     Delay, Packet Loss and Reordering
          RFC 4901: Protocol Extensions for Header Compression over MPLS";
     }

     identity iphc {
       base iana-pw-types;
       description
         "IPHC Transport Header-compressed Packets.";
       reference

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         "RFC 2507: IP Header Compression
          RFC 4901: Protocol Extensions for Header Compression over MPLS";
     }

     identity crtp {
       base iana-pw-types;
       description
         "cRTP Transport Header-compressed Packets.";
       reference
         "RFC 2508: Compressing IP/UDP/RTP Headers for Low-Speed Serial
                    Links
          RFC 4901: Protocol Extensions for Header Compression over MPLS";
     }

     identity atm-vp-virtual-trunk {
       base iana-pw-types;
       description
         "ATM VP Virtual Trunk.";
     }

     identity fc-port-mode {
       base iana-pw-types;
       description
         "FC Port Mode.";
       reference
         "RFC 6307: Encapsulation Methods for Transport of
                    Fibre Channel Traffic over MPLS Networks";
     }

     identity wildcard {
       base iana-pw-types;
       description
         "Wildcard.";
       reference
         "RFC 4863: Wildcard Pseudowire Type";
     }
   }
   <CODE ENDS>

8.3.  Ethernet Segments

   The "ietf-ethernet-segment" YANG module uses types defined in
   [RFC6991].

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   <CODE BEGINS>
   file "ietf-ethernet-segment@2021-10-01.yang"
   module ietf-ethernet-segment {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-ethernet-segment";
     prefix l2vpn-es;

     import ietf-yang-types {
       prefix yang;
       reference
         "RFC 6991: Common YANG Data Types, Section 3";
     }

     organization
       "IETF OPSA (Operations and Management Area) Working Group";
     contact
       "WG Web:   <https://datatracker.ietf.org/wg/opsawg/>
        WG List:  <mailto:opsawg@ietf.org>

        Editor:    Mohamed Boucadair
                  <mailto:mohamed.boucadair@orange.com>
        Editor:    Samier Barguil
                  <mailto:samier.barguilgiraldo.ext@telefonica.com>
        Author:    Oscar Gonzalez de Dios
                  <mailto:oscar.gonzalezdedios@telefonica.com>";
     description
       "This YANG module defines a model for Ethernet Segments.

        Copyright (c) 2021 IETF Trust and the persons identified as
        authors of the code.  All rights reserved.

        Redistribution and use in source and binary forms, with or
        without modification, is permitted pursuant to, and subject
        to the license terms contained in, the Simplified BSD License
        set forth in Section 4.c of the IETF Trust's Legal Provisions
        Relating to IETF Documents
        (http://trustee.ietf.org/license-info).

        This version of this YANG module is part of RFC XXXX; see
        the RFC itself for full legal notices.";

     revision 2021-10-01 {
       description
         "Initial version.";
       reference
         "RFC XXXX: A Layer 2 VPN Network YANG Model.";
     }

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     /* Identities */

     identity esi-type {
       description
         "T-(Ethernet Segment Identifier (ESI) Type) is a 1-octet field
          (most significant octet) that specifies the format of the
          remaining 9 octets (ESI Value).";
       reference
         "RFC 7432: BGP MPLS-Based Ethernet VPN, Section 5";
     }

     identity esi-type-0 {
       base esi-type;
       description
         "This type indicates an arbitrary 9-octet ESI value,
          which is managed and configured by the operator.";
     }

     identity esi-type-1 {
       base esi-type;
       description
         "When IEEE 802.1AX Link Aggregation Control Protocol (LACP)
          is used between the Provider Edge (PE) and Customer Edge (CE)
          devices, this ESI type indicates an auto-generated ESI value
          determined from LACP.";
       reference
         "IEEE Std. 802.1AX: Link Aggregation";
     }

     identity esi-type-2 {
       base esi-type;
       description
         "The ESI value is auto-generated and determined based
          on the Layer 2 bridge protocol.";
     }

     identity esi-type-3 {
       base esi-type;
       description
         "This type indicates a MAC-based ESI value that can be
          auto-generated or configured by the operator.";
     }

     identity esi-type-4 {
       base esi-type;
       description
         "This type indicates a Router-ID ESI value that can be
          auto-generated or configured by the operator.";

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     }

     identity esi-type-5 {
       base esi-type;
       description
         "This type indicates an Autonomous System (AS)-based ESI value
          that can be auto-generated or configured by the operator.";
     }

     identity df-election-methods {
       description
         "Base Identity Designated Forwarder (DF) election method.";
     }

     identity default-7432 {
       base df-election-methods;
       description
         "The default DF election method.

          The default procedure for DF election at the granularity of <ES,
          VLAN> for VLAN-based service or <ES, VLAN bundle> for VLAN-
          (aware) bundle service is referred to as 'service carving'.";
       reference
         "RFC 7432: BGP MPLS-Based Ethernet VPN, Section 8.5";
     }

     identity highest-random-weight {
       base df-election-methods;
       description
         "The highest random weight (HRW) method.";
       reference
         "RFC 8584: Framework for Ethernet VPN Designated
                    Forwarder Election Extensibility, Section 3";
     }

     identity preference {
       base df-election-methods;
       description
         "The preference based method. PEs are assigned with
          preferences to become the DF in the Ethernet Segment (ES).
          The exact preference-based algorithm (e.g., lowest-preference
          algorithm, highest-preference algorithm) to use is
          signaled at the control plane.";
     }

     identity evpn-redundancy-mode {
       description
         "Base identity for Ethernet VPN (EVPN) redundancy modes.";

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     }

     identity single-active {
       base evpn-redundancy-mode;
       description
         "Indicates Single-Active redundancy mode for a given ES.";
       reference
         "RFC 7432: BGP MPLS-Based Ethernet VPN, Section 14.1.1";
     }

     identity all-active {
       base evpn-redundancy-mode;
       description
         "Indicates All-Active redundancy mode for a given ES.";
       reference
         "RFC 7432: BGP MPLS-Based Ethernet VPN, Section 14.1.2";
     }

     identity evpn-service-type {
       description
         "Base identity for EVPN service type.";
     }

     identity vlan-based-service-interface {
       base evpn-service-type;
       description
         "VLAN-Based Service Interface.";
       reference
         "RFC 7432: BGP MPLS-Based Ethernet VPN, Section 6.1";
     }

     identity vlan-bundle-service-interface {
       base evpn-service-type;
       description
         "VLAN Bundle Service Interface.";
       reference
         "RFC 7432: BGP MPLS-Based Ethernet VPN, Section 6.2";
     }

     identity vlan-aware-bundle-service-interface {
       base evpn-service-type;
       description
         "VLAN-Aware Bundle Service Interface.";
       reference
         "RFC 7432: BGP MPLS-Based Ethernet VPN, Section 6.3";
     }

     /* Main Ethernet Segment Container */

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     container ethernet-segments {
       description
         "Top container for the Ethernet Segment Identifier (ESI).";
       list ethernet-segment {
         key "name";
         description
           "Top list for ESIs.";
         leaf name {
           type string;
           description
             "Includes the name of the Ethernet Segment (ES).";
         }
         leaf esi-type {
           type identityref {
             base esi-type;
           }
           default "esi-type-0";
           description
             "T-(ESI Type) is a 1-octet field (most significant
              octet) that specifies the format of the remaining
              9 octets (ESI Value).";
           reference
             "RFC 7432: BGP MPLS-Based Ethernet VPN, Section 5";
         }
         choice esi-choice {
           description
             "Ethernet segment choice between several types.
              For ESI Type 0: The esi is directly configured by the
                              operator.
              For ESI Type 1: The auto-mode must be used.
              For ESI Type 2: The auto-mode must be used.
              For ESI Type 3: The directly-assigned or auto-mode must
                              be used.
              For ESI Type 4: The directly-assigned or auto-mode must
                              be used.
              For ESI Type 5: The directly-assigned or auto-mode must
                              be used.";
           case directly-assigned {
             description
               "Explicitly assign an ESI value.";
             leaf ethernet-segment-identifier {
               type yang:hex-string {
                 length "29";
               }
               description
                 "10-octet ESI.";
             }
           }

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           case auto-assigned {
             description
               "The ESI is auto-assigned.";
             container esi-auto {
               description
                 "The ESI is auto-assigned.";
               choice auto-mode {
                 description
                   "Indicates the auto-assignment mode. ESI can be
                    automatically assigned either with or without
                    indicating a pool from which the ESI should be
                    taken.

                    For both cases, the server will auto-assign an
                    ESI value 'auto-assigned-ESI' and use that value
                    operationally.";
                 case from-pool {
                   leaf esi-pool-name {
                     type string;
                     description
                       "The auto-assignment will be made from the
                        pool identified by the ESI-pool-name.";
                   }
                 }
                 case full-auto {
                   leaf auto {
                     type empty;
                     description
                       "Indicates an ESI is fully auto-assigned.";
                   }
                 }
               }
               leaf auto-ethernet-segment-identifier {
                 type yang:hex-string {
                   length "29";
                 }
                 config false;
                 description
                   "The value of the auto-assigned ESI.";
               }
             }
           }
         }
         leaf esi-redundancy-mode {
           type identityref {
             base evpn-redundancy-mode;
           }
           description

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             "Indicates the EVPN redundancy mode for a multihomed
              CE.";
           reference
             "RFC 7432: BGP MPLS-Based Ethernet VPN, Section 14.1";
         }
         container df-election {
           description
             "Top container for the DF election method properties.";
           leaf df-election-method {
             type identityref {
               base df-election-methods;
             }
             default "default-7432";
             description
               "Specifies the DF election method.";
             reference
               "RFC 8584: Framework for Ethernet VPN Designated
                          Forwarder Election Extensibility";
           }
           leaf preference {
             when "derived-from-or-self(../df-election-method, "
                + "'preference')" {
               description
                 "The preference value is only applicable
                  to the preference based method.";
             }
             type uint16;
             description
               "Defines a 2-octet value that indicates the PE
                preference to become the DF in the ES.";
             reference
               "RFC 8584: Framework for Ethernet VPN Designated
                          Forwarder Election Extensibility";
           }
           leaf revertive {
             when "derived-from-or-self(../df-election-method, "
                + "'preference')" {
               description
                 "The revertive value is only applicable
                  to the preference method.";
             }
             type boolean;
             default "true";
             description
               "The 'preempt' or 'revertive' behavior. This
                option allows a non-revertive behavior in the
                DF election.";
             reference

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               "RFC 8584: Framework for Ethernet VPN Designated
                          Forwarder Election Extensibility";
           }
           leaf election-wait-time {
             type uint32;
             description
               "Election wait timer.";
             reference
               "RFC 8584: Framework for Ethernet VPN Designated
                          Forwarder Election Extensibility";
           }
         }
         leaf split-horizon-filtering {
           type boolean;
           description
             "Controls split-horizon filtering.

              In order to achieve split-horizon filtering, every
              Broadcast, unknown unicast, or multicast (BUM)
              packet originating from a non-DF PE is encapsulated
              with an MPLS label that identifies the origin ES.";
           reference
             "RFC 7432: BGP MPLS-Based Ethernet VPN, Section 5";
         }
         container pbb {
           description
             "Provider Backbone Bridging (PBB) parameters .";
           reference
             "IEEE 802.1ah: Provider Backbone Bridge";
           leaf backbone-src-mac {
             type yang:mac-address;
             description
               "The PEs connected to the same CE must share the
                same Provider Backbone (B-MAC) address in
                All-Active mode.";
             reference
               "RFC 7623: Provider Backbone Bridging Combined with
                          Ethernet VPN (PBB-EVPN), Section 6.2.1.1";
           }
         }
         list member {
           key "ne-id interface-id";
           description
             "Includes a list of ES members.";
           leaf ne-id {
             type string;
             description
               "Unique identifier of the network element where the ES

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                is configured with a service provider network.";
           }
           leaf interface-id {
             type string;
             description
               "Identifier of a node interface.";
           }
         }
       }
     }
   }
   <CODE ENDS>

8.4.  L2NM

   The "ietf-l2vpn-ntw" YANG module uses types defined in [RFC6991],
   [I-D.ietf-opsawg-vpn-common], and [RFC8294].

   <CODE BEGINS>
   file "ietf-l2vpn-ntw@2021-10-01.yang"
   module ietf-l2vpn-ntw {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-l2vpn-ntw";
     prefix l2vpn-ntw;

     import ietf-inet-types {
       prefix inet;
       reference
         "RFC 6991: Common YANG Data Types, Section 4";
     }
     import ietf-yang-types {
       prefix yang;
       reference
         "RFC 6991: Common YANG Data Types, Section 3";
     }
     import ietf-vpn-common {
       prefix vpn-common;
       reference
         "RFC CCCC: A Layer 2/3 VPN Common YANG Model";
     }
     import iana-bgp-l2-encaps {
       prefix iana-bgp-l2-encaps;
     }
     import iana-pseudowire-types {
       prefix iana-pw-types;
     }
     import ietf-routing-types {
       prefix rt-types;

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       reference
         "RFC 8294: Common YANG Data Types for the Routing Area";
     }

     organization
       "IETF OPSA (Operations and Management Area) Working Group";
     contact
       "WG Web:   <https://datatracker.ietf.org/wg/opsawg/>
        WG List:  <mailto:opsawg@ietf.org>

        Editor:    Mohamed Boucadair
                  <mailto:mohamed.boucadair@orange.com>
        Editor:    Samier Barguil
                  <mailto:samier.barguilgiraldo.ext@telefonica.com>
        Author:    Oscar Gonzalez de Dios
                  <mailto:oscar.gonzalezdedios@telefonica.com>";
     description
       "This YANG module defines a network model for layer 2 VPN
        services.

        Copyright (c) 2021 IETF Trust and the persons identified as
        authors of the code.  All rights reserved.

        Redistribution and use in source and binary forms, with or
        without modification, is permitted pursuant to, and subject
        to the license terms contained in, the Simplified BSD License
        set forth in Section 4.c of the IETF Trust's Legal Provisions
        Relating to IETF Documents
        (http://trustee.ietf.org/license-info).

        This version of this YANG module is part of RFC XXXX; see
        the RFC itself for full legal notices.";

     revision 2021-10-01 {
       description
         "Initial version.";
       reference
         "RFC XXXX: A Layer 2 VPN Network YANG Model.";
     }

     /* Features */

     feature oam-3ah {
       description
         "Indicates the support of OAM 802.3ah.";
       reference
         "IEEE Std 802.3ah: Media Access Control Parameters, Physical
                            Layers, and  Management Parameters for

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                            Subscriber Access Networks";
     }

     /* Identities */

     identity evpn-service-type {
       description
         "Base identity for EVPN service type.";
     }

     identity vlan-based-service-interface {
       base evpn-service-type;
       description
         "VLAN-Based Service Interface.";
       reference
         "RFC 7432: BGP MPLS-Based Ethernet VPN, Section 6.1";
     }

     identity vlan-bundle-service-interface {
       base evpn-service-type;
       description
         "VLAN Bundle Service Interface.";
       reference
         "RFC 7432: BGP MPLS-Based Ethernet VPN, Section 6.2";
     }

     identity vlan-aware-bundle-service-interface {
       base evpn-service-type;
       description
         "VLAN-Aware Bundle Service Interface.";
       reference
         "RFC 7432: BGP MPLS-Based Ethernet VPN, Section 6.3";
     }

     identity mapping-type {
       base vpn-common:multicast-gp-address-mapping;
       description
         "Identity for multicast group mapping type.";
     }

     identity loop-prevention-type {
       description
         "Identity of loop prevention.";
     }

     identity shut {
       base loop-prevention-type;
       description

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         "Shut protection type.";
     }

     identity trap {
       base loop-prevention-type;
       description
         "Trap protection type.";
     }

     identity color-type {
       description
         "Identity of color types.";
     }

     identity green {
       base color-type;
       description
         "'green' color type.";
     }

     identity yellow {
       base color-type;
       description
         "'yellow' color type.";
     }

     identity red {
       base color-type;
       description
         "'red' color type.";
     }

     identity t-ldp-pw-type {
       description
         "Identity for t-ldp-pw-type.";
     }

     identity vpws-type {
       base t-ldp-pw-type;
       description
         "Virtual Private Wire Service (VPWS) t-ldp-pw-type.";
       reference
         "RFC 4664: Framework for Layer 2 Virtual Private Networks
                   (L2VPNs), Section 3.3";
     }

     identity vpls-type {
       base t-ldp-pw-type;

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       description
         "Virtual Private LAN Service (VPLS) t-ldp-pw-type.";
       reference
         "RFC 4762: Virtual Private LAN Service (VPLS) Using
                    Label Distribution Protocol (LDP)
                    Signaling, Section 6.1";
     }

     identity hvpls {
       base t-ldp-pw-type;
       description
         "Identity for Hierarchical Virtual Private LAN Service (H-VPLS)
          t-ldp-pw-type.";
       reference
         "RFC 4762: Virtual Private LAN Service (VPLS) Using
                    Label Distribution Protocol (LDP)
                    Signaling, Section 10";
     }

     identity lacp-mode {
       description
         "Identity of the LACP mode.";
     }

     identity lacp-active {
       base lacp-mode;
       description
         "LACP active mode.

          This mode refers to the mode where auto-speed negotiation
          is initiated followed by an establishment of an
          Ethernet channel with the other end.";
     }

     identity lacp-passive {
       base lacp-mode;
       description
         "LACP passive mode.

          This mode refers to the LACP mode where an endpoint does
          not initiate the negotiation, but only responds to LACP
          packets initiated by the other end (e.g., full duplex
          or half duplex)";
     }

     identity pm-type {
       description
         "Identity for performance monitoring type.";

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     }

     identity loss {
       base pm-type;
       description
         "Loss measurement is the performance monitoring type.";
     }

     identity delay {
       base pm-type;
       description
         "Delay measurement is the performance monitoring type.";
     }

     identity mac-learning-mode {
       description
         "Media Access Control (MAC) learning mode.";
     }

     identity data-plane {
       base mac-learning-mode;
       description
         "User MAC addresses are learned through ARP broadcast.";
     }

     identity control-plane {
       base mac-learning-mode;
       description
         "User MAC addresses are advertised through EVPN-BGP.";
     }

     identity mac-action {
       description
         "Base identity for a MAC action.";
     }

     identity drop {
       base mac-action;
       description
         "Dropping a packet as the MAC action.";
     }

     identity flood {
       base mac-action;
       description
         "Packet flooding as the MAC action.";
     }

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     identity warning {
       base mac-action;
       description
         "Sending a warning log message as the MAC action.";
     }

     identity precedence-type {
       description
         "Redundancy type. The service can be created
          with primary and secondary signalization.";
     }

     identity primary {
       base precedence-type;
       description
         "Identifies the main VPN network access.";
     }

     identity secondary {
       base precedence-type;
       description
         "Identifies the secondary VPN network access.";
     }

     identity pw-type {
       description
         "Identity for allowed LDP-based pseudowire (PW) type.";
       reference
         "RFC 4762: Virtual Private LAN Service (VPLS) Using
                    Label Distribution Protocol (LDP)
                    Signaling, Section 6.1.1";
     }

     identity ethernet {
       base pw-type;
       description
         "PW Ethernet type.";
     }

     identity ethernet-tagged {
       base pw-type;
       description
         "PW Ethernet tagged mode type.";
     }

     /* Typedefs */

     typedef ccm-priority-type {

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       type uint8 {
         range "0..7";
       }
       description
         "A 3-bit priority value to be used in the VLAN tag,
          if present in the transmitted frame.";
     }

     /* Groupings */

     grouping cfm-802 {
       description
         "Grouping for 802.1ag Connectivity Fault Management (CFM)
          attributes.";
       reference
         "IEEE Std 802-1ag: Virtual Bridged Local Area Networks
                            Amendment 5: Connectivity Fault Management";
       leaf maid {
         type string;
         description
           "Maintenance Association Identifier (MAID).";
       }
       leaf mep-id {
         type uint32;
         description
           "Local Maintenance End Point (MEP) ID.";
       }
       leaf mep-level {
         type uint32;
         description
           "MEP level.";
       }
       leaf mep-up-down {
         type enumeration {
           enum up {
             description
               "MEP is up.";
           }
           enum down {
             description
               "MEP is down.";
           }
         }
         description
           "MEP up/down.";
       }
       leaf remote-mep-id {
         type uint32;

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         description
           "Remote MEP ID.";
       }
       leaf cos-for-cfm-pdus {
         type uint32;
         description
           "Class of service for CFM PDUs.";
       }
       leaf ccm-interval {
         type uint32;
         description
           "Continuity Check Message (CCM) interval.";
       }
       leaf ccm-holdtime {
         type uint32;
         description
           "CCM hold time.";
       }
       leaf ccm-p-bits-pri {
         type ccm-priority-type;
         description
           "The priority parameter for Continuity Check Messages (CCMs)
            transmitted by the MEP.";
       }
     }

     grouping y-1731 {
       description
         "Grouping for y.1731";
       reference
         "ITU-T Y-1731:  Operations, administration and maintenance
                         (OAM) functions and mechanisms for
                         Ethernet-based networks";
       list y-1731 {
         key "maid";
         description
           "List for y-1731.";
         leaf maid {
           type string;
           description
             "MAID.";
         }
         leaf mep-id {
           type uint32;
           description
             "Local MEP ID.";
         }
         leaf pm-type {

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           type identityref {
             base pm-type;
           }
           description
             "Performance monitor types.";
         }
         leaf remote-mep-id {
           type uint32;
           description
             "Remote MEP ID.";
         }
         leaf message-period {
           type uint32;
           units "milliseconds";
           description
             "Defines the interval between OAM messages.";
         }
         leaf measurement-interval {
           type uint32;
           units "seconds";
           description
             "Specifies the measurement interval for statistics.";
         }
         leaf cos {
           type uint32;
           description
             "Identifies the Class of Service.";
         }
         leaf loss-measurement {
           type boolean;
           description
             "Controls whether loss measurement is enabled/disabled.";
         }
         leaf synthethic-loss-measurement {
           type boolean;
           description
             "Indicates whether synthetic loss measurement is enabled.";
         }
         container delay-measurement {
           description
             "Container for delay measurement";
           leaf enable-dm {
             type boolean;
             description
               "Controls whether delay measurement is enabled/disabled.";
           }
           leaf two-way {
             type boolean;

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             description
               "Whether delay measurement is two-way ('true') of one-
                way ('false').";
           }
         }
         leaf frame-size {
           type uint32;
           units "bytes";
           description
             "Indicates the frame size.";
         }
         leaf session-type {
           type enumeration {
             enum proactive {
               description
                 "Proactive mode.";
             }
             enum on-demand {
               description
                 "On-demand mode.";
             }
           }
           description
             "Specifies the session type.";
         }
       }
     }

     grouping global-parameters-profile {
       description
         "Container for per-service parameters.";
       leaf local-autonomous-system {
         type inet:as-number;
         description
           "Indicates a local AS Number (ASN).";
       }
       leaf svc-mtu {
         type uint32;
         description
           "Service MTU, it is also known as the maximum transmission unit
            or maximum frame size. When a frame is larger than the MTU,
            it is fragmented to accommodate the MTU of the network.";
       }
       leaf ce-vlan-preservation {
         type boolean;
         description
           "Preserve the CE-VLAN ID from ingress to egress,i.e.,
            CE-VLAN tag of the egress frame are identical to

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            those of the ingress frame that yielded this egress
            service frame. If All-to-One bundling within a site
            is Enabled, then preservation applies to all Ingress
            service frames. If All-to-One bundling is disabled,
            then preservation applies to tagged Ingress service
            frames having CE-VLAN ID 1 through 4094.";
       }
       leaf ce-vlan-cos-preservation {
         type boolean;
         description
           "CE VLAN CoS preservation. PCP bits in the CE-VLAN tag
            of the egress frame are identical to those of the ingress
            frame that yielded this egress service frame.";
       }
       leaf control-word-negotiation {
         type boolean;
         description
           "Controls whether Control-word negotiation is enabled
            (if set to true) or not (if set to false).";
         reference
           "Section 7 of RFC 8077";
       }
       container mac-policies {
         description
           "Container of MAC policies.";
         container mac-addr-limit {
           description
             "Container of MAC-Addr limit configuration.";
           leaf mac-num-limit {
             type uint16;
             description
               "Maximum number of MAC addresses learned from
                the customer for a single service instance.";
           }
           leaf time-interval {
             type uint32;
             units "milliseconds";
             description
               "The aging time of the mac address.";
           }
           leaf action {
             type identityref {
               base mac-action;
             }
             description
               "Specifies the action when the upper limit is
                exceeded: drop the packet, flood the
                packet, or simply send a warning log message.";

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           }
         }
         container mac-loop-prevention {
           description
             "Container for MAC loop prevention.";
           leaf window {
             type uint32;
             units "seconds";
             default "180";
             description
               "The timer when a MAC mobility event is detected.";
           }
           leaf frequency {
             type uint32;
             default "5";
             description
               "The number of times to detect MAC duplication, where
                a 'duplicate MAC address' situation has occurred and
                the duplicate MAC address has been added to a list of
                duplicate MAC addresses.";
           }
           leaf retry-timer {
             type uint32;
             units "seconds";
             description
               "The retry timer. When the retry timer expires,
                the duplicate MAC address will be flushed from
                the MAC-VRF.";
           }
           leaf protection-type {
             type identityref {
               base loop-prevention-type;
             }
             description
               "Protection type.";
           }
         }
       }
       container multicast-like {
         if-feature "vpn-common:multicast";
         description
           "Multicast-like container.";
         leaf enabled {
           type boolean;
           default "false";
           description
             "Enables multicast.";
         }

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         container customer-tree-flavors {
           description
             "Type of trees used by customer.";
           leaf-list tree-flavor {
             type identityref {
               base vpn-common:multicast-tree-type;
             }
             description
               "Type of multicast tree to be used.";
           }
         }
       }
     }

     /* Main L2NM Container */

     container l2vpn-ntw {
       description
         "Container for the L2NM.";
       container vpn-profiles {
         description
           "Container for VPN profiles.";
         uses vpn-common:vpn-profile-cfg;
       }
       container vpn-services {
         description
           "Container for L2VPN services.";
         list vpn-service {
           key "vpn-id";
           description
             "Container of a VPN service.";
           uses vpn-common:vpn-description;
           leaf parent-service-id {
             type vpn-common:vpn-id;
             description
               "Pointer to the parent service that
                triggered the L2NM.";
           }
           leaf vpn-type {
             type identityref {
               base vpn-common:service-type;
             }
             must "not(derived-from-or-self(current(), "
                + "'vpn-common:l3vpn'))" {
               error-message "L3VPN is only applicable in L3NM.";
             }
             description
               "Service type.";

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           }
           leaf vpn-service-topology {
             type identityref {
               base vpn-common:vpn-topology;
             }
             description
               "Defining service topology, such as
                any-to-any, hub-spoke, etc.";
           }
           leaf bgp-ad-enabled {
             type boolean;
             description
               "Indicates whether BGP auto-discovery is enabled
                or disabled.";
           }
           leaf signaling-type {
             type identityref {
               base vpn-common:vpn-signaling-type;
             }
             description
               "VPN signaling type.";
           }
           container global-parameters-profiles {
             description
               "Container for a list of global parameters profiles.";
             list global-parameters-profile {
               key "profile-id";
               description
                 "List of global parameters profiles.";
               leaf profile-id {
                 type string;
                 description
                   "The identifier of the global parameters profile.";
               }
               uses vpn-common:route-distinguisher;
               uses vpn-common:vpn-route-targets;
               uses global-parameters-profile;
             }
           }
           container underlay-transport {
             description
               "Container for the underlay transport.";
             uses vpn-common:underlay-transport;
           }
           uses vpn-common:service-status;
           container vpn-nodes {
             description
               "Set of VPN nodes that are involved in the L2NM.";

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             list vpn-node {
               key "vpn-node-id";
               description
                 "Container of the VPN nodes.";
               leaf vpn-node-id {
                 type vpn-common:vpn-id;
                 description
                   "Sets the identifier of the VPN node.";
               }
               leaf description {
                 type string;
                 description
                   "Textual description of a VPN node.";
               }
               leaf ne-id {
                 type string;
                 description
                   "Indicates the node's IP address.";
               }
               leaf role {
                 type identityref {
                   base vpn-common:role;
                 }
                 default "vpn-common:any-to-any-role";
                 description
                   "Role of the VPN node in the VPN.";
               }
               leaf router-id {
                 type rt-types:router-id;
                 description
                   "A 32-bit number in the dotted-quad format that is
                    used to uniquely identify a node within an
                    autonomous system (AS). ";
               }
               container active-global-parameters-profiles {
                 description
                   "Container for a list of global parameters profiles.";
                 list global-parameters-profile {
                   key "profile-id";
                   description
                     "List of active global parameters profiles.";
                   leaf profile-id {
                     type leafref {
                       path "/l2vpn-ntw/vpn-services/vpn-service"
                          + "/global-parameters-profiles"
                          + "/global-parameters-profile/profile-id";
                     }
                     description

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                       "Points to a global profile defined at the
                        service level.";
                   }
                   uses global-parameters-profile;
                 }
               }
               uses vpn-common:service-status;
               container bgp-auto-discovery {
                 when "/l2vpn-ntw/vpn-services/vpn-service"
                    + "/bgp-ad-enabled = 'true'" {
                   description
                     "Only applies when BGP auto-discovery is enabled.";
                 }
                 description
                   "BGP is used for auto-discovery.";
                 choice bgp-type {
                   description
                     "Choice for the BGP type.";
                   case l2vpn-bgp {
                     description
                       "Container for BGP L2VPN.";
                     leaf vpn-id {
                       type vpn-common:vpn-id;
                       description
                         "VPN Identifier. This identifier serves to unify
                          components of a given VPN for the sake of
                          auto-discovery.";
                       reference
                         "RFC 6624: Layer 2 Virtual Private Networks Using
                                    BGP for Auto-Discovery and Signaling";
                     }
                   }
                   case evpn-bgp {
                     when "derived-from-or-self(/l2vpn-ntw/vpn-services"
                        + "/vpn-service/vpn-type, 'vpn-common:vpws-evpn') "
                        + "or derived-from-or-self(/l2vpn-ntw/vpn-services"
                        + "/vpn-service/vpn-type, 'vpn-common:pbb-evpn') "
                        + "or derived-from-or-self(/l2vpn-ntw/vpn-services"
                        + "/vpn-service/vpn-type, 'vpn-common:mpls-evpn') "
                        + "or derived-from-or-self(/l2vpn-ntw/vpn-services"
                        + "/vpn-service/vpn-type, "
                        + "'vpn-common:vxlan-evpn')" {
                       description
                         "Can only be used when EVPN is used.";
                     }
                     description
                       "EVPN case.";
                     leaf evpn-type {

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                       type leafref {
                         path "/l2vpn-ntw/vpn-services/vpn-service"
                            + "/vpn-type";
                       }
                       description
                         "EVPN type.";
                     }
                     leaf auto-rt-enable {
                       type boolean;
                       default "false";
                       description
                         "Enables/disabled RT auto-derivation based on
                          the ASN and Ethernet Tag ID.";
                       reference
                         "RFC 7432: BGP MPLS-Based Ethernet VPN,
                                    Section 7.10.1";
                     }
                     leaf auto-route-target {
                       when "../auto-rt-enable = 'true'" {
                         description
                           "Can only be used when auto-RD is enabled.";
                       }
                       type rt-types:route-target;
                       config false;
                       description
                         "The value of the auto-assigned RT.";
                     }
                   }
                 }
                 uses vpn-common:route-distinguisher;
                 uses vpn-common:vpn-route-targets;
               }
               container signaling-option {
                 description
                   "Container for the L2VPN signaling.";
                 leaf advertise-mtu {
                   type boolean;
                   description
                     "Controls whether MTU is advertised.";
                   reference
                     "RFC 4667: Layer 2 Virtual Private Network (L2VPN)
                                Extensions for Layer 2 Tunneling
                                Protocol (L2TP), Section 4.3";
                 }
                 leaf mtu-allow-mismatch {
                   type boolean;
                   description
                     "When set to true, it allows MTU mismatch.";

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                   reference
                     "RFC 4667: Layer 2 Virtual Private Network (L2VPN)
                                Extensions for Layer 2 Tunneling
                                Protocol (L2TP), Section 4.3";
                 }
                 leaf signaling-type {
                   type leafref {
                     path "/l2vpn-ntw/vpn-services/vpn-service"
                        + "/signaling-type";
                   }
                   description
                     "VPN signaling type.";
                 }
                 choice signaling-option {
                   description
                     "Choice for the signaling-option.";
                   case bgp {
                     description
                       "BGP is used as the signaling protocol.";
                     choice bgp-type {
                       description
                         "Choice for the BGP type.";
                       case l2vpn-bgp {
                         description
                           "Container for BGP L2VPN.";
                         leaf ce-id {
                           type uint16;
                           description
                             "The PE must know the set of virtual circuits
                              connecting it to the CE and a CE ID
                              identifying the CE within the VPN.";
                           reference
                             "RFC 6624: Layer 2 Virtual Private Networks
                                        Using BGP for Auto-Discovery and
                                        Signaling";
                         }
                         leaf ce-range {
                           type uint16;
                           description
                             "Determines the number of remote CEs with
                              which a given CE can communicate in the
                               context of a VPN.";
                           reference
                             "RFC 6624: Layer 2 Virtual Private Networks
                                        Using BGP for Auto-Discovery and
                                        Signaling";
                         }
                         leaf pw-encapsulation-type {

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                           type identityref {
                             base iana-bgp-l2-encaps:bgp-l2-encaps-type;
                           }
                           description
                             "PW encapsulation type.";
                         }
                         container vpls-instance {
                           when "derived-from-or-self(/l2vpn-ntw"
                              + "/vpn-services/vpn-service/vpn-type, "
                              + "'vpn-common:vpls')" {
                             description
                               "Only applies for VPLS.";
                           }
                           description
                             "VPLS instance.";
                           leaf vpls-edge-id {
                             type uint16;
                             description
                               "VPLS Edge Identifier (VE ID).";
                             reference
                               "RFC 4761: Virtual Private LAN Service
                                          (VPLS) Using BGP for Auto-
                                          Discovery and Signaling";
                           }
                           leaf vpls-edge-id-range {
                             type uint16;
                             description
                               "Specifies the size of the range of VE ID in
                                a VPLS service. The range controls the size
                                of the label block advertised in the
                                context of a VPLS instance.";
                             reference
                               "RFC 4761: Virtual Private LAN Service
                                          (VPLS) Using BGP for Auto-
                                          Discovery and Signaling";
                           }
                         }
                       }
                       case evpn-bgp {
                         description
                           "Used for EVPN.";
                         leaf evpn-type {
                           type leafref {
                             path "/l2vpn-ntw/vpn-services/vpn-service"
                                + "/vpn-nodes/vpn-node/bgp-auto-discovery"
                                + "/evpn-type";
                           }
                           description

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                             "EVPN type.";
                         }
                         leaf service-interface-type {
                           type identityref {
                             base evpn-service-type;
                           }
                           description
                             "EVPN service interface type.";
                         }
                         container evpn-policies {
                           description
                             "Includes a set of EVPN policies such as those
                              related to handling MAC addresses.";
                           leaf mac-learning-mode {
                             type identityref {
                               base mac-learning-mode;
                             }
                             description
                               "Indicates through which plane MAC addresses
                                are advertised.";
                           }
                           leaf ingress-replication {
                             type boolean;
                             description
                               "Controls whether ingress replication is
                                enabled/disabled.";
                             reference
                               "RFC 7432: BGP MPLS-Based Ethernet VPN,
                                          Section 8.3.1.1";
                           }
                           leaf p2mp-replication {
                             type boolean;
                             description
                               "Controles whether P2MP replication is
                                enabled/disabled.";
                             reference
                               "RFC 7432: BGP MPLS-Based Ethernet VPN,
                                          Section 8.3.1.2";
                           }
                           container arp-proxy {
                             if-feature "vpn-common:ipv4";
                             description
                               "Top container for the ARP proxy.";
                             leaf enable {
                               type boolean;
                               default "false";
                               description
                                 "Enables (when set to 'true') or disables

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                                  (when set to 'false') ARP proxy.";
                               reference
                                 "RFC 7432: BGP MPLS-Based Ethernet VPN,
                                            Section 10";
                             }
                             leaf arp-suppression {
                               type boolean;
                               default "false";
                               description
                                 "Enables (when set to 'true') or disables
                                  (when set to 'false') ARP suppression.";
                               reference
                                 "RFC 7432: BGP MPLS-Based Ethernet VPN";
                             }
                             leaf ip-mobility-threshold {
                               type uint16;
                               description
                                 "It is possible for a given host (as
                                  defined by its IP address) to move from
                                  one ES  to another.
                                  IP mobility threshold specifies the
                                  number of IP mobility events
                                  that are detected for a given IP address
                                  within the detection-threshold before it
                                  is identified as a duplicate IP address.
                                  Once the detection threshold is reached,
                                  updates for the IP address are
                                  suppressed.";
                             }
                             leaf duplicate-ip-detection-interval {
                               type uint16;
                               description
                                 "The time interval used in detecting a
                                  duplicate IP address. Duplicate IP
                                  address detection number of host moves
                                  are allowed within this interval
                                  period.";
                             }
                           }
                           container nd-proxy {
                             if-feature "vpn-common:ipv6";
                             description
                               "Top container for the ND proxy.";
                             leaf enable {
                               type boolean;
                               default "false";
                               description
                                 "Enables (when set to 'true') or disables

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                                  (when set to 'false') ND proxy.";
                               reference
                                 "RFC 7432: BGP MPLS-Based Ethernet VPN,
                                            Section 10";
                             }
                             leaf nd-suppression {
                               type boolean;
                               default "false";
                               description
                                 "Enables (when set to 'true') or disables
                                  (when set to 'false') Neighbor Discovery
                                  (ND) message suppression.
                                  ND suppression is a technique that is
                                  used to reduce the amount of ND packets
                                  flooding within individual segments,
                                  that is between hosts connected to the
                                  same logical switch.";
                             }
                             leaf ip-mobility-threshold {
                               type uint16;
                               description
                                 "It is possible for a given host (as
                                  defined by its IP address) to move from
                                  one ES  to another.
                                  IP mobility threshold specifies the
                                  number of IP mobility events
                                  that are detected for a given IP address
                                  within the detection-threshold before it
                                  is identified as a duplicate IP address.
                                  Once the detection threshold is reached,
                                  updates for the IP address are
                                  suppressed.";
                             }
                             leaf duplicate-ip-detection-interval {
                               type uint16;
                               description
                                 "The time interval used in detecting a
                                  duplicate IP address. Duplicate IP
                                  address detection number of host moves
                                  are allowed within this interval
                                  period.";
                             }
                           }
                           leaf underlay-multicast {
                             type boolean;
                             default "false";
                             description
                               "Enables (when set to 'true') or disables

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                                (when set to 'false') underlay multicast.";
                           }
                           leaf flood-unknown-unicast-supression {
                             type boolean;
                             default "false";
                             description
                               "Enables (when set to 'true') or disables
                                (when set to 'false') unknown flood unicast
                                suppression.";
                           }
                           leaf vpws-vlan-aware {
                             type boolean;
                             default "false";
                             description
                               "Enables (when set to 'true') or disables
                                (when set to 'false') VPWS VLAN-aware.";
                           }
                           container bum-management {
                             description
                               "Broadcast-unknown-unicast-multicast
                                management.";
                             leaf discard-broadcast {
                               type boolean;
                               description
                                 "Discards broadcast, when enabled.";
                             }
                             leaf discard-unknown-multicast {
                               type boolean;
                               description
                                 "Discards unknown multicast, when
                                  enabled.";
                             }
                             leaf discard-unknown-unicast {
                               type boolean;
                               description
                                 "Discards unknown unicast, when enabled.";
                             }
                           }
                           container pbb {
                             when "derived-from-or-self(../../evpn-type,"
                                + " 'pbb-evpn')" {
                               description
                                 "Only applies for PBB EVPN.";
                             }
                             description
                               "PBB parameters container.";
                             reference
                               "IEEE 802.1ah: Provider Backbone Bridge";

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                             leaf backbone-src-mac {
                               type yang:mac-address;
                               description
                                 "Includes provider backbone MAC (B-MAC)
                                  address.";
                               reference
                                 "RFC 7623: Provider Backbone Bridging
                                            Combined with Ethernet VPN
                                            (PBB-EVPN), Section 8.1";
                             }
                           }
                         }
                       }
                     }
                   }
                   container ldp-or-l2tp {
                     description
                       "Container for LDP or L2TP-signaled PWs.";
                     leaf agi {
                       type rt-types:route-distinguisher;
                       description
                         "Attachment Group Identifier. Also, called
                          VPLS-Id.";
                       reference
                         "RFC 4667: Layer 2 Virtual Private Network (L2VPN)
                                    Extensions for Layer 2 Tunneling
                                    Protocol (L2TP), Section 4.3
                          RFC 4762: Virtual Private LAN Service (VPLS)
                                    Using Label Distribution Protocol (LDP)
                                    Signaling, Section 6.1.1";
                     }
                     leaf saii {
                       type uint32;
                       description
                         "Source Attachment Individual Identifier (SAII).";
                       reference
                         "RFC 4667: Layer 2 Virtual Private Network (L2VPN)
                                    Extensions for Layer 2 Tunneling
                                    Protocol (L2TP), Section 3";
                     }
                     list remote-targets {
                       key "taii";
                       description
                         "List of allowed target Attachment Individual
                          Identifier (AII) and peers.";
                       reference
                         "RFC 4667: Layer 2 Virtual Private Network (L2VPN)
                                    Extensions for Layer 2 Tunneling

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                                    Protocol (L2TP), Section 5";
                       leaf taii {
                         type uint32;
                         description
                           "Target Attachment Individual Identifier.";
                         reference
                           "RFC 4667: Layer 2 Virtual Private Network
                                      (L2VPN) Extensions for Layer 2
                                      Tunneling  Protocol (L2TP),
                                      Section 3";
                       }
                       leaf peer-addr {
                         type inet:ip-address;
                         description
                           "Indicates the peer forwarder's IP address.";
                       }
                     }
                     choice ldp-or-l2tp {
                       description
                         "Choice of LDP or L2TP-signaled PWs.";
                       case ldp {
                         description
                           "Container for T-LDP PW configurations.";
                         leaf t-ldp-pw-type {
                           type identityref {
                             base t-ldp-pw-type;
                           }
                           description
                             "T-LDP PW type.";
                         }
                         leaf pw-type {
                           type identityref {
                             base pw-type;
                           }
                           description
                             "PW encapsulation type.";
                           reference
                             "RFC 4762: Virtual Private LAN Service (VPLS)
                                        Using Label Distribution Protocol
                                        (LDP) Signaling, Section 6.1.1";
                         }
                         leaf pw-description {
                           type string;
                           description
                             "Includes an interface description used to
                              send a human-readable administrative
                              string describing the interface to the
                              remote.";

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                           reference
                             "RFC 4762: Virtual Private LAN Service (VPLS)
                                        Using Label Distribution Protocol
                                        (LDP) Signaling, Section 6.1.1";
                         }
                         leaf mac-addr-withdraw {
                           type boolean;
                           description
                             "If set to 'true', then MAC address withdrawal
                              is enabled.  If 'false', then MAC address
                              withdrawal is disabled.";
                           reference
                             "RFC 4762: Virtual Private LAN Service (VPLS)
                                        Using Label Distribution Protocol
                                        (LDP) Signaling, Section 6.2";
                         }
                         list pw-peer-list {
                           key "peer-addr vc-id";
                           description
                             "List of AC and PW bindings.";
                           leaf peer-addr {
                             type inet:ip-address;
                             description
                               "Indicates the peer's IP address.";
                           }
                           leaf vc-id {
                             type string;
                             description
                               "VC label used to identify a PW.";
                           }
                           leaf pw-priority {
                             type uint32;
                             description
                               "Defines the priority for the PW.
                                The higher the pw-priority value, the
                                higher the preference of the PW will be.";
                           }
                         }
                         container qinq {
                           when "derived-from-or-self(../t-ldp-pw-type, "
                              + "'hvpls')" {
                             description
                               "Only applies when t-ldp pw type is
                                h-vpls.";
                           }
                           description
                             "Container for QinQ.";
                           leaf s-tag {

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                             type uint32;
                             mandatory true;
                             description
                               "S-TAG.";
                           }
                           leaf c-tag {
                             type uint32;
                             mandatory true;
                             description
                               "C-TAG.";
                           }
                         }
                       }
                       case l2tp {
                         description
                           "Container for L2TP PWs.";
                         leaf router-id {
                           type rt-types:router-id;
                           description
                             "A 32-bit number in the dotted-quad format
                              that is used to uniquely identify a node
                              within an autonomous system.";
                           reference
                             "RFC 4667: Layer 2 Virtual Private Network
                                        (L2VPN) Extensions for Layer 2
                                        Tunneling Protocol (L2TP),
                                        Section 4.2";
                         }
                         leaf pseudowire-type {
                           type identityref {
                             base iana-pw-types:iana-pw-types;
                           }
                           description
                             "Encapsulation type.";
                           reference
                             "RFC 4667: Layer 2 Virtual Private Network
                                        (L2VPN) Extensions for Layer 2
                                        Tunneling Protocol (L2TP),
                                        Section 4.2";
                         }
                       }
                     }
                   }
                 }
               }
               container vpn-network-accesses {
                 description
                   "Main container for VPN network accesses.";

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                 list vpn-network-access {
                   key "id";
                   description
                     "List of VPN network accesses.";
                   leaf id {
                     type vpn-common:vpn-id;
                     description
                       "Identifier of the network access";
                   }
                   leaf description {
                     type string;
                     description
                       "A textual description of the VPN network access.";
                   }
                   leaf interface-id {
                     type string;
                     description
                       "Refers to a physical or logical interface.";
                   }
                   leaf global-parameters-profile {
                     type leafref {
                       path "/l2vpn-ntw/vpn-services/vpn-service/vpn-nodes"
                          + "/vpn-node/active-global-parameters-profiles"
                          + "/global-parameters-profile/profile-id";
                     }
                     description
                       "An identifier of an active VPN instance profile.";
                   }
                   uses vpn-common:service-status;
                   container connection {
                     description
                       "Container for the bearer and AC.";
                     leaf l2-termination-point {
                       type string;
                       description
                         "Specifies a reference to a local layer 2
                          termination point such as a layer 2
                          sub-interface.";
                     }
                     leaf local-bridge-reference {
                       type string;
                       description
                         "Specifies a local bridge reference to
                          accommodate, for example, implementations
                          that require internal bridging.
                          A reference may be a local bridge domain.";
                     }
                     leaf bearer-reference {

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                       if-feature "vpn-common:bearer-reference";
                       type string;
                       description
                         "This is an internal reference for the service
                          provider to identify the bearer associated
                          with this VPN.";
                     }
                     container encapsulation {
                       description
                         "Container for layer 2 encapsulation.";
                       leaf encap-type {
                         type identityref {
                           base vpn-common:encapsulation-type;
                         }
                         default "vpn-common:priority-tagged";
                         description
                           "Tagged interface type. By default, the type of
                            the tagged interface is 'priority-tagged'.";
                       }
                       container dot1q {
                         when "derived-from-or-self(../encap-type, "
                            + "'vpn-common:dot1q')" {
                           description
                             "Only applies when the type of the
                              tagged interface is 'dot1q'.";
                         }
                         description
                           "Tagged interface.";
                         leaf tag-type {
                           type identityref {
                             base vpn-common:tag-type;
                           }
                           default "vpn-common:c-vlan";
                           description
                             "Tag type. By default, the tag type is
                              'c-vlan'.";
                         }
                         leaf cvlan-id {
                           type uint16;
                           description
                             "VLAN identifier.";
                         }
                         container rewrite {
                           description
                             "Sets the tag rewriting policy for this
                              'vpn-network-accesses'. Enables the
                              manipulation of the layer-2 frame header for
                              data frames as they are processed on the

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                              'vpn-network-access'.";
                           choice tag-choice {
                             description
                               "Selects the tag rewriting policy for a VPN
                                network access. It defines a set of
                                standard tag manipulations that allow for
                                the insertion, removal, or rewriting of one
                                or two 802.1Q VLAN tags.";
                             leaf pop {
                               type enumeration {
                                 enum 1 {
                                   description
                                     "Allows one (1) tag removal.";
                                 }
                                 enum 2 {
                                   description
                                     "Allows two (2) tags removal.";
                                 }
                               }
                               description
                                 "Standard tag removal.
                                  The number of 802.1Q VLAN tags to pop.";
                             }
                             leaf push {
                               type empty;
                               description
                                 "Standard tag Push.
                                  The number of 802.1Q tags to push on the
                                  front of the frame.";
                             }
                             leaf translate {
                               type enumeration {
                                 enum 1-to-1 {
                                   description
                                     "Allows one (1) to one (1) tag
                                      translation.";
                                 }
                                 enum 1-to-2 {
                                   description
                                     "Allows one (1) to two (2) tags
                                      translation.";
                                 }
                                 enum 2-to-1 {
                                   description
                                     "Allows two (2) to one (1) tag
                                      translation.";
                                 }
                                 enum 2-to-2 {

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                                   description
                                     "Allows two (2) to two (2) tags
                                      translation.";
                                 }
                               }
                               description
                                 "Replaces tags with other tags.
                                  Translate operations are expressed as
                                  as a combination of tag push and pop
                                  operations. For example, translating the
                                  outer tag is expressed as popping a
                                  single tag.";
                             }
                           }
                           leaf cvlan-id {
                             when 'not(../pop)';
                             type uint16;
                             description
                               "Push/Translate vlan tags";
                           }
                           leaf direction {
                             type enumeration {
                               enum symmetric {
                                 description
                                   "TAGs operation is performed in a
                                    symmetric way.

                                    The operation is performed on the
                                    outbound traffic on an interface, then
                                    the reverse operation is performed on
                                    the inbound traffic out of the
                                    same interface.";
                               }
                             }
                             description
                               "Indicates the direction.";
                           }
                         }
                       }
                       container priority-tagged {
                         when "derived-from-or-self(../encap-type, "
                            + "'vpn-common:priority-tagged')" {
                           description
                             "Only applies when the type of the
                              tagged interface is 'priority-tagged'.";
                         }
                         description
                           "Priority tagged container.";

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                         leaf tag-type {
                           type identityref {
                             base vpn-common:tag-type;
                           }
                           default "vpn-common:c-vlan";
                           description
                             "Tag type. By default, the tag type is
                              'c-vlan'.";
                         }
                       }
                       container qinq {
                         when "derived-from-or-self(../encap-type, "
                            + "'vpn-common:qinq')" {
                           description
                             "Only applies when the type of the tagged
                              interface is QinQ.";
                         }
                         description
                           "Includes QinQ parameters.";
                         leaf tag-type {
                           type identityref {
                             base vpn-common:tag-type;
                           }
                           default "vpn-common:s-c-vlan";
                           description
                             "Tag type. By default, the tag type is
                              's-c-vlan'.";
                         }
                         leaf svlan-id {
                           type uint16;
                           mandatory true;
                           description
                             "S-VLAN identifier.";
                         }
                         leaf cvlan-id {
                           type uint16;
                           mandatory true;
                           description
                             "C-VLAN identifier.";
                         }
                       }
                     }
                     container lag-interface {
                       if-feature "vpn-common:lag-interface";
                       description
                         "Container of LAG interface attributes
                          configuration.";
                       leaf lag-interface-id {

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                         type string;
                         description
                           "LAG interface identifier.";
                       }
                       container lacp {
                         description
                           "Container for LACP.";
                         leaf lacp-state {
                           type boolean;
                           default "false";
                           description
                             "Controls whether LACP is enabled.";
                         }
                         leaf mode {
                           type identityref {
                             base lacp-mode;
                           }
                           description
                             "Indicates the LACP mode.";
                         }
                         leaf speed {
                           type uint32;
                           units "mbps";
                           default "10";
                           description
                             "LACP speed. By default, the LACP speed is 10
                              Mbps.";
                         }
                         leaf mini-link-num {
                           type uint32;
                           description
                             "Defines the minimum number of links that must
                              be active before the aggregating link is put
                              into service.";
                         }
                         leaf system-id {
                           type yang:mac-address;
                           description
                             "Indicates the System ID used by LACP.";
                         }
                         leaf admin-key {
                           type uint16;
                           description
                             "Indicates the value of the key used for the
                              aggregate interface.";
                         }
                         leaf system-priority {
                           type uint16 {

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                             range "0..65535";
                           }
                           default "32768";
                           description
                             "Indicates the LACP priority for the
                              system.";
                         }
                         container member-link-list {
                           description
                             "Container of Member link list.";
                           list member-link {
                             key "name";
                             description
                               "Member link.";
                             leaf name {
                               type string;
                               description
                                 "Member link name.";
                             }
                             leaf port-speed {
                               type uint32;
                               description
                                 "Port speed.";
                             }
                             leaf mode {
                               type identityref {
                                 base vpn-common:neg-mode;
                               }
                               description
                                 "Negotiation mode.";
                             }
                             leaf link-mtu {
                               type uint32;
                               description
                                 "Link MTU size.";
                             }
                             container oam-802.3ah-link {
                               if-feature "oam-3ah";
                               description
                                 "Container for oam 802.3 ah link.";
                               leaf enable {
                                 type boolean;
                                 description
                                   "Indicates support of OAM 802.3 ah
                                    link.";
                               }
                             }
                           }

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                         }
                         leaf flow-control {
                           type string;
                           description
                             "Indicates whtehr flow control is
                              supported.";
                         }
                         leaf lldp {
                           type boolean;
                           description
                             "Indicates whether Link Layer Discovery
                              Protocol (LLDP) is supported.";
                         }
                       }
                       container split-horizon {
                         description
                           "Configuration with split horizon enabled.";
                         leaf group-name {
                           type string;
                           description
                             "Group name of the Split Horizon.";
                         }
                       }
                     }
                   }
                   container vpws-service-instance {
                     when "derived-from-or-self(/l2vpn-ntw/vpn-services"
                        + "/vpn-service/vpn-type, "
                        + "'vpn-common:vpws-evpn')" {
                       description
                         "Only applies for EVPN-VPWS.";
                     }
                     description
                       "Local and remote VPWS Service Instance (VSI)";
                     reference
                       "RFC 8214: Virtual Private Wire Service Support
                                  in Ethernet VPN";
                     choice local-vsi-choice {
                       description
                         "Choices for assigning local VSI.";
                       case directly-assigned {
                         description
                           "Explicitly assign a local VSI.";
                         leaf local-vpws-service-instance {
                           type uint32 {
                             range "1..16777215";
                           }
                           description

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                             "Indicates the assigned local VSI.";
                         }
                       }
                       case auto-assigned {
                         description
                           "The local VSI is auto-assigned.";
                         container local-vsi-auto {
                           description
                             "The local VSI is auto-assigned.";
                           choice auto-mode {
                             description
                               "Indicates the auto-assignment mode of
                                local VSI. VSI can be automatically
                                assigned either with or without
                                indicating a pool from which the VSI
                                should be taken.

                                For both cases, the server will
                                auto-assign a local VSI value and use
                                that value.";
                             case from-pool {
                               leaf vsi-pool-name {
                                 type string;
                                 description
                                   "The auto-assignment will be made
                                    from this pool.";
                               }
                             }
                             case full-auto {
                               leaf auto {
                                 type empty;
                                 description
                                   "Indicates that a local VSI is
                                    fully auto-assigned.";
                               }
                             }
                           }
                           leaf auto-local-vsi {
                             type uint32 {
                               range "1..16777215";
                             }
                             config false;
                             description
                               "The value of the auto-assigned local
                                VSI.";
                           }
                         }
                       }

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                     }
                     choice remote-vsi-choice {
                       description
                         "Choice for assigning the remote VSI.";
                       case directly-assigned {
                         description
                           "Explicitly assign a remote VSI.";
                         leaf remote-vpws-service-instance {
                           type uint32 {
                             range "1..16777215";
                           }
                           description
                             "Indicates the value of the remote
                              VSI.";
                         }
                       }
                       case auto-assigned {
                         description
                           "The remote VSI is auto-assigned.";
                         container remote-vsi-auto {
                           description
                             "The remote VSI is auto-assigned.";
                           choice auto-mode {
                             description
                               "Indicates the auto-assignment mode
                                of remote VSI. VSI can be
                                automatically assigned either with or
                                without indicating a pool from which
                                the VSI should be taken.

                                For both cases, the server will
                                auto-assign a remote VSI value and use
                                that value.";
                             case from-pool {
                               leaf vsi-pool-name {
                                 type string;
                                 description
                                   "The auto-assignment will be made
                                    from this pool.";
                               }
                             }
                             case full-auto {
                               leaf auto {
                                 type empty;
                                 description
                                   "Indicates that a remote VSI is fully
                                    auto-assigned.";
                               }

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                             }
                           }
                           leaf auto-remote-vsi {
                             type uint32 {
                               range "1..16777215";
                             }
                             config false;
                             description
                               "The value of the auto-assigned remote
                                VSI.";
                           }
                         }
                       }
                     }
                   }
                   list group {
                     key "group-id";
                     description
                       "List of group-ids.";
                     leaf group-id {
                       type string;
                       description
                         "Indicates the group-id to which the network
                          access belongs to.";
                     }
                     leaf precedence {
                       type identityref {
                         base precedence-type;
                       }
                       description
                         "Defining service redundancy in transport
                          network.";
                     }
                     leaf ethernet-segment-identifier {
                       type string;
                       description
                         "Reference to the ESI associated to the VPN
                          network access.";
                     }
                   }
                   container ethernet-service-oam {
                     description
                       "Container for Ethernet service OAM.";
                     leaf md-name {
                       type string;
                       description
                         "Maintenance domain name.";
                     }

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                     leaf md-level {
                       type uint8;
                       description
                         "Maintenance domain level.";
                     }
                     container cfm-802.1-ag {
                       description
                         "Container of 802.1ag CFM configurations.";
                       list n2-uni-c {
                         key "maid";
                         description
                           "List of UNI-N to UNI-C.";
                         uses cfm-802;
                       }
                       list n2-uni-n {
                         key "maid";
                         description
                           "List of UNI-N to UNI-N.";
                         uses cfm-802;
                       }
                     }
                     uses y-1731;
                   }
                   container service {
                     description
                       "Container for service";
                     leaf mtu {
                       type uint32;
                       description
                         "MTU, it is also known as the maximum
                          transmission unit or maximum frame size. When a
                          frame is larger than the MTU, it is broken down,
                          or fragmented, into smaller pieces by the
                          network protocol to accommodate the MTU of the
                          network";
                     }
                     container svc-inbound-bandwidth {
                       if-feature "vpn-common:inbound-bw";
                       description
                         "From the PE perspective, the service inbound
                          bandwidth of the connection.";
                       list inbound-bandwidth {
                         key "bw-type";
                         description
                           "List for input bandwidth data nodes.";
                         leaf bw-type {
                           type identityref {
                             base vpn-common:bw-type;

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                           }
                           description
                             "Indicates the bandwidth type.";
                         }
                         leaf cos-id {
                           if-feature "vpn-common:qos";
                           type uint8;
                           description
                             "Identifier of the Class of Service (CoS),
                              indicated by DSCP or a CE-CLAN
                              CoS (802.1p) value in the service frame.";
                         }
                         leaf cir {
                           type uint64;
                           units "bps";
                           description
                             "Committed Information Rate. The maximum
                              number of bits that a port can receive or
                              send during one-second over an interface.";
                         }
                         leaf cbs {
                           type uint64;
                           units "bps";
                           description
                             "Committed Burst Size. CBS controls the bursty
                              nature of the traffic. Traffic that does not
                              use the configured CIR accumulates credits
                              until the credits reach the configured CBS.";
                         }
                         leaf eir {
                           type uint64;
                           units "bps";
                           description
                             "Excess Information Rate, i.e., excess frame
                              delivery allowed not subject to SLA. The
                              traffic rate can be limited by EIR.";
                         }
                         leaf ebs {
                           type uint64;
                           units "bps";
                           description
                             "Excess Burst Size. The bandwidth available
                              for burst traffic from the EBS is subject to
                              the amount of bandwidth that is accumulated
                              during periods when traffic allocated by the
                              EIR policy is not used.";
                         }
                         leaf pir {

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                           type uint64;
                           units "bps";
                           description
                             "Peak Information Rate, i.e., maximum frame
                              delivery allowed. It is equal to or less
                              than sum of CIR and EIR.";
                         }
                         leaf pbs {
                           type uint64;
                           units "Bytes per Second";
                           description
                             "Peak Burst Size.";
                         }
                       }
                     }
                     container svc-outbound-bandwidth {
                       if-feature "vpn-common:outbound-bw";
                       description
                         "From the PE perspective, the service outbound
                          bandwidth of the connection.";
                       list outbound-bandwidth {
                         key "bw-type";
                         description
                           "List for outbound bandwidth";
                         leaf bw-type {
                           type identityref {
                             base vpn-common:bw-type;
                           }
                           description
                             "Bandwidth Type.";
                         }
                         leaf cos-id {
                           if-feature "vpn-common:qos";
                           type uint8;
                           description
                             "Identifier of the CoS, indicated by
                              DSCP or a CE-CLAN CoS (802.1p) value in
                              the service frame.";
                         }
                         leaf cir {
                           type uint64;
                           units "bps";
                           description
                             "Committed Information Rate. The maximum
                              number of bits that a port can receive or
                              send during one-second over an interface.";
                         }
                         leaf cbs {

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                           type uint64;
                           units "bps";
                           description
                             "Committed Burst Size. CBS controls the bursty
                              nature of the traffic. Traffic that does not
                              use the configured CIR accumulates credits
                              until the credits reach the configured CBS.";
                         }
                         leaf eir {
                           type uint64;
                           units "bps";
                           description
                             "Excess Information Rate, i.e., excess frame
                              delivery allowed not subject to SLA. The
                              traffic rate can be limited by EIR.";
                         }
                         leaf ebs {
                           type uint64;
                           units "bps";
                           description
                             "Excess Burst Size. The bandwidth available
                              for burst traffic from the EBS is subject to
                              the amount of bandwidth that is accumulated
                              during periods when traffic allocated by the
                              EIR policy is not used.";
                         }
                         leaf pir {
                           type uint64;
                           units "bps";
                           description
                             "Peak Information Rate, i.e., maximum frame
                              delivery allowed. It is equal to or less than
                              sum of CIR and EIR.";
                         }
                         leaf pbs {
                           type uint64;
                           units "Bytes per Second";
                           description
                             "Peak Burst Size.";
                         }
                       }
                     }
                     container qos {
                       if-feature "vpn-common:qos";
                       description
                         "QoS configuration.";
                       container qos-classification-policy {
                         description

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                           "Configuration of the traffic classification
                            policy.";
                         list rule {
                           key "id";
                           ordered-by user;
                           description
                             "List of classification rules.";
                           leaf id {
                             type string;
                             description
                               "A description identifying the QoS
                                classification policy rule.";
                           }
                           choice match-type {
                             default "match-flow";
                             description
                               "Choice for classification.";
                             case match-flow {
                               container match-flow {
                                 description
                                   "Describes flow-matching criteria.";
                                 leaf dscp {
                                   type inet:dscp;
                                   description
                                     "DSCP value.";
                                 }
                                 leaf dot1q {
                                   type uint16;
                                   description
                                     "802.1Q matching. It is a VLAN tag
                                      added into a frame.";
                                 }
                                 leaf pcp {
                                   type uint8 {
                                     range "0..7";
                                   }
                                   description
                                     "PCP value.";
                                 }
                                 leaf src-mac-address {
                                   type yang:mac-address;
                                   description
                                     "Source MAC address.";
                                 }
                                 leaf dst-mac-address {
                                   type yang:mac-address;
                                   description
                                     "Destination MAC address.";

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                                 }
                                 leaf color-type {
                                   type identityref {
                                     base color-type;
                                   }
                                   description
                                     "Color type.";
                                 }
                                 leaf any {
                                   type empty;
                                   description
                                     "Allows all.";
                                 }
                               }
                             }
                             case match-application {
                               leaf match-application {
                                 type identityref {
                                   base vpn-common:customer-application;
                                 }
                                 description
                                   "Defines the application to match.";
                               }
                             }
                           }
                           leaf target-class-id {
                             type string;
                             description
                               "Identification of the CoS.
                                This identifier is internal to the
                                administration.";
                           }
                         }
                       }
                       container qos-profile {
                         description
                           "QoS profile configuration.";
                         list qos-profile {
                           key "profile";
                           description
                             "QoS profile.
                              Can be standard profile or customized
                              profile.";
                           leaf profile {
                             type leafref {
                               path "/l2vpn-ntw/vpn-profiles"
                                  + "/valid-provider-identifiers"
                                  + "/qos-profile-identifier/id";

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                             }
                             description
                               "QoS profile to be used.";
                           }
                           leaf direction {
                             type identityref {
                               base vpn-common:qos-profile-direction;
                             }
                             default "vpn-common:both";
                             description
                               "The direction to which the QoS profile
                                is applied.";
                           }
                         }
                       }
                     }
                     container mac-policies {
                       description
                         "Container for MAC-related policies.";
                       list access-control-list {
                         key "name";
                         description
                           "Container for access control List.";
                         leaf name {
                           type string;
                           description
                             "Specifies the name of the ACL.";
                         }
                         leaf-list src-mac-address {
                           type yang:mac-address;
                           description
                             "Specifies the source MAC address.";
                         }
                         leaf-list src-mac-address-mask {
                           type yang:mac-address;
                           description
                             "Specifies the source MAC address mask.";
                         }
                         leaf-list dst-mac-address {
                           type yang:mac-address;
                           description
                             "Specifies the destination MAC address.";
                         }
                         leaf-list dst-mac-address-mask {
                           type yang:mac-address;
                           description
                             "Specifies the destination MAC address mask.";
                         }

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                         leaf action {
                           type identityref {
                             base mac-action;
                           }
                           default "drop";
                           description
                             "Specifies the filtering action.";
                         }
                         leaf rate-limit {
                           when "derived-from-or-self(../action, "
                              + "'flood')" {
                             description
                               "Rate-limit is valid only when the action is
                                to accept the matching frame.";
                           }
                           type decimal64 {
                             fraction-digits 2;
                           }
                           units "bytes per second";
                           description
                             "Specifies how to rate-limit the traffic.";
                         }
                       }
                       container mac-loop-prevention {
                         description
                           "Container of MAC loop prevention.";
                         leaf window {
                           type uint32;
                           units "seconds";
                           default "180";
                           description
                             "The timer when a MAC mobility event is
                              detected.";
                         }
                         leaf frequency {
                           type uint32;
                           default "5";
                           description
                             "The number of times to detect MAC
                              duplication, where a 'duplicate MAC address'
                              situation has occurred and the duplicate MAC
                              address has been added to a list of duplicate
                              MAC addresses.";
                         }
                         leaf retry-timer {
                           type uint32;
                           units "seconds";
                           description

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                             "The retry timer. When the retry timer
                              expires, the duplicate MAC address will be
                              flushed from the MAC-VRF.";
                         }
                         leaf protection-type {
                           type identityref {
                             base loop-prevention-type;
                           }
                           description
                             "Protection type";
                         }
                       }
                       container mac-addr-limit {
                         description
                           "Container of MAC-Addr limit configurations";
                         leaf mac-num-limit {
                           type uint16;
                           description
                             "maximum number of MAC addresses learned from
                              the subscriber for a single service
                              instance.";
                         }
                         leaf time-interval {
                           type uint32;
                           units "milliseconds";
                           description
                             "The aging time of the mac address.";
                         }
                         leaf action {
                           type identityref {
                             base mac-action;
                           }
                           description
                             "specify the action when the upper limit is
                              exceeded: drop the packet, flood the
                              packet, or simply send a warning log
                              message.";
                         }
                       }
                     }
                     container broadcast-unknown-unicast-multicast {
                       description
                         "Container of broadcast, unknown unicast, and
                          multicast configurations";
                       leaf multicast-site-type {
                         type enumeration {
                           enum receiver-only {
                             description

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                               "The site only has receivers.";
                           }
                           enum source-only {
                             description
                               "The site only has sources.";
                           }
                           enum source-receiver {
                             description
                               "The site has both sources and receivers.";
                           }
                         }
                         default "source-receiver";
                         description
                           "Type of the multicast site.";
                       }
                       list multicast-gp-address-mapping {
                         key "id";
                         description
                           "List of Port to group mappings.";
                         leaf id {
                           type uint16;
                           description
                             "Unique identifier for the mapping.";
                         }
                         leaf vlan-id {
                           type uint32;
                           description
                             "The VLAN ID of the Multicast group.";
                         }
                         leaf mac-gp-address {
                           type yang:mac-address;
                           description
                             "The MAC address of the Multicast group.";
                         }
                         leaf port-lag-number {
                           type uint32;
                           description
                             "The ports/LAGs belonging to the Multicast
                              group.";
                         }
                       }
                       leaf bum-overall-rate {
                         type uint32;
                         description
                           "Overall rate for BUM.";
                       }
                     }
                   }

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                 }
               }
             }
           }
         }
       }
     }
   }
   <CODE ENDS>

9.  Security Considerations

   The YANG modules specified in this document defines schema for data
   that is designed to be accessed via network management protocols such
   as NETCONF [RFC6241] or RESTCONF [RFC8040] . The lowest NETCONF layer
   is the secure transport layer, and the mandatory-to-implement secure
   transport is Secure Shell (SSH) [RFC6242].  The lowest RESTCONF layer
   is HTTPS, and the mandatory-to-implement secure transport is TLS
   [RFC8446].

   The Network Configuration Access Control Model (NACM) [RFC8341]
   provides the means to restrict access for particular NETCONF or
   RESTCONF users to a preconfigured subset of all available NETCONF or
   RESTCONF protocol operations and content.

   There are a number of data nodes defined in "ietf-l2vpn-ntw" and
   "ietf-ethernet-segment" YANG modules that are writable/creatable/
   deletable (i.e., config true, which is the default).  These data
   nodes may be considered sensitive or vulnerable in some network
   environments.  Write operations (e.g., edit-config) and delete
   operations to these data nodes without proper protection or
   authentication can have a negative effect on network operations.
   These are the subtrees and data nodes and their sensitivity/
   vulnerability in the "ietf-l2vpn-ntw" and "ietf-ethernet-segment"
   modules:

   *  'vpn-profiles': This container includes a set of sensitive data
      that influence how the L3VPN service is delivered.  For example,
      an attacker who has access to these data nodes may be able to
      manipulate routing policies, QoS policies, or encryption
      properties.  These data nodes are defined with "nacm:default-deny-
      write" tagging [I-D.ietf-opsawg-vpn-common].

   *  'ethernet-segments' and 'vpn-services': An attacker who is able to
      access network nodes can undertake various attacks, such as
      deleting a running L2VPN service, interrupting all the traffic of
      a client.  In addition, an attacker may modify the attributes of a
      running service (e.g., QoS, bandwidth) or an ES, leading to

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      malfunctioning of the service and therefore to SLA violations.  In
      addition, an attacker could attempt to create an L2VPN service or
      add a new network access.  In addition to using NACM to prevent
      authorized access, such activity can be detected by adequately
      monitoring and tracking network configuration changes.

   Some of the readable data nodes in the "ietf-l2vpn-ntw" YANG module
   may be considered sensitive or vulnerable in some network
   environments.  It is thus important to control read access (e.g., via
   get, get-config, or notification) to these data nodes.  These are the
   subtrees and data nodes and their sensitivity/vulnerability:

   *  'customer-name' and 'ip-connection': An attacker can retrieve
      privacy-related information which can be used to track a customer.
      Disclosing such information may be considered as a violation of
      the customer-provider trust relationship.

   Both "iana-bgp-l2-encaps" and "iana-pseudowire-types" modules define
   YANG identities for encapsulation/pseudowires types.  These
   identities are intended to be referenced by other YANG modules, and
   by themselves do not expose any nodes which are writable, contain
   read-only state, or RPCs.

10.  IANA Considerations

10.1.  YANG Modules

   This document requests IANA to register the following URIs in the
   "ns" subregistry within the "IETF XML Registry" [RFC3688]:

         URI: urn:ietf:params:xml:ns:yang:iana-bgp-l2-encaps
         Registrant Contact: The IESG.
         XML: N/A; the requested URI is an XML namespace.

         URI: urn:ietf:params:xml:ns:yang:iana-pseudowire-types
         Registrant Contact: The IESG.
         XML: N/A; the requested URI is an XML namespace.

         URI: urn:ietf:params:xml:ns:yang:ietf-ethernet-segment
         Registrant Contact: The IESG.
         XML: N/A; the requested URI is an XML namespace.

         URI: urn:ietf:params:xml:ns:yang:ietf-l2vpn-ntw
         Registrant Contact: The IESG.
         XML: N/A; the requested URI is an XML namespace.

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   This document requests IANA to register the following YANG modules in
   the "YANG Module Names" subregistry [RFC6020] within the "YANG
   Parameters" registry:

         name: iana-bgp-l2-encaps
         namespace: urn:ietf:params:xml:ns:yang:iana-bgp-l2-encaps
         maintained by IANA: Y
         prefix: iana-bgp-l2-encaps
         reference: RFC XXXX

         name: iana-pseudowire-types
         namespace: urn:ietf:params:xml:ns:yang:iana-pseudowire-types
         maintained by IANA: Y
         prefix: iana-pw-types
         reference: RFC XXXX

         name: ietf-ethernet-segment
         namespace: urn:ietf:params:xml:ns:yang:ietf-ethernet-segment
         maintained by IANA: N
         prefix: l2vpn-es
         reference: RFC XXXX

         name: ietf-l2vpn-ntw
         namespace: urn:ietf:params:xml:ns:yang:ietf-l2vpn-ntw
         maintained by IANA: N
         prefix: l2vpn-ntw
         reference: RFC XXXX

10.2.  BGP Layer 2 Encapsulation Types

   This document defines the initial version of the IANA-maintained
   "iana-bgp-l2-encaps" YANG module.  IANA is requested to add this note
   for both modules:

      BGP Layer 2 encapsulation types must not be directly added to the
      "iana-bgp-l2-encaps" YANG module.  They must instead be
      respectively added to the "BGP Layer 2 Encapsulation Types"
      registry [IANA-BGP-L2].

   When a Layer 2 encapsulation type is added to the "BGP Layer 2
   Encapsulation Types" registry, a new "identity" statement must be
   added to the "iana-bgp-l2-encaps" YANG module.  The name of the
   "identity" is the lower-case of encapsulation name provided in the
   description.  The "identity" statement should have the following sub-
   statements defined:

   "base":        Contains 'bgp-l2-encaps-type'.

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   "description":  Replicates the description from the registry.

   "reference":   Replicates the reference from the registry and add the
                  title of the document.

   Unassigned or reserved values are not present in the module.

   When the "iana-bgp-l2-encaps" YANG module is updated, a new
   "revision" statement must be added in front of the existing revision
   statements.

   IANA is requested to add this note to [IANA-BGP-L2]:

      When this registry is modified, the YANG module "iana-bgp-
      l2-encaps" must be updated as defined in RFCXXXX.

10.3.  Pseudowire Types

   This document defines the initial version of the IANA-maintained
   "iana-pseudowire-types" YANG module.  IANA is requested to add this
   note for both modules:

      MPLS pseudowire types must not be directly added to the "iana-bgp-
      l2-encaps" YANG module.  They must instead be respectively added
      to the "MPLS Pseudowire Types" registry [IANA-PW-Types].

   When a pseudowire type is added to the "iana-pseudowire-types"
   registry, a new "identity" statement must be added to the "iana-
   pseudowire-types" YANG module.  The name of the "identity" is the
   lower-case of encapsulation name provided in the description.  The
   "identity" statement should have the following sub-statements
   defined:

   "base":        Contains 'iana-pw-types'.

   "description":  Replicates the description from the registry.

   "reference":   Replicates the reference from the registry and add the
                  title of the document.

   Unassigned or reserved values are not present in the module.

   When the "iana-pseudowire-types" YANG module is updated, a new
   "revision" statement must be added in front of the existing revision
   statements.

   IANA is requested to add this note to [IANA-PW-Types]:

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      When this registry is modified, the YANG module "iana-pseudowire-
      types" must be updated as defined in RFCXXXX.

11.  References

11.1.  Normative References

   [I-D.ietf-opsawg-vpn-common]
              Barguil, S., Dios, O. G. D., Boucadair, M., and Q. Wu, "A
              Layer 2/3 VPN Common YANG Model", Work in Progress,
              Internet-Draft, draft-ietf-opsawg-vpn-common-12, 29
              September 2021, <https://www.ietf.org/archive/id/draft-
              ietf-opsawg-vpn-common-12.txt>.

   [IANA-BGP-L2]
              Internet Assigned Numbers Authority, "BGP Layer 2
              Encapsulation Types", <https://www.iana.org/assignments/
              bgp-parameters/bgp-parameters.xhtml#bgp-l2-encapsulation-
              types-registry>.

   [IANA-PW-Types]
              IANA, "MPLS Pseudowire Types Registry",
              <http://www.iana.org/assignments/pwe3-parameters/
              pwe3-parameters.xhtml#pwe3-parameters-2>.

   [IEEE-802-1ag]
              IEEE, "802.1ag - 2007 - IEEE Standard for Local and
              Metropolitan Area Networks - Virtual Bridged Local Area
              Networks Amendment 5: Connectivity Fault Management",
              2007, <DOI 10.1109/IEEESTD.2007.4431836>.

   [ITU-T-Y-1731]
              Union, I. T., "Operations, administration and maintenance
              (OAM) functions and mechanisms for Ethernet-based
              networks", August 2015,
              <https://www.itu.int/rec/T-REC-Y.1731/en>.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <https://www.rfc-editor.org/info/rfc3688>.

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   [RFC4667]  Luo, W., "Layer 2 Virtual Private Network (L2VPN)
              Extensions for Layer 2 Tunneling Protocol (L2TP)",
              RFC 4667, DOI 10.17487/RFC4667, September 2006,
              <https://www.rfc-editor.org/info/rfc4667>.

   [RFC4761]  Kompella, K., Ed. and Y. Rekhter, Ed., "Virtual Private
              LAN Service (VPLS) Using BGP for Auto-Discovery and
              Signaling", RFC 4761, DOI 10.17487/RFC4761, January 2007,
              <https://www.rfc-editor.org/info/rfc4761>.

   [RFC4762]  Lasserre, M., Ed. and V. Kompella, Ed., "Virtual Private
              LAN Service (VPLS) Using Label Distribution Protocol (LDP)
              Signaling", RFC 4762, DOI 10.17487/RFC4762, January 2007,
              <https://www.rfc-editor.org/info/rfc4762>.

   [RFC6020]  Bjorklund, M., Ed., "YANG - A Data Modeling Language for
              the Network Configuration Protocol (NETCONF)", RFC 6020,
              DOI 10.17487/RFC6020, October 2010,
              <https://www.rfc-editor.org/info/rfc6020>.

   [RFC6074]  Rosen, E., Davie, B., Radoaca, V., and W. Luo,
              "Provisioning, Auto-Discovery, and Signaling in Layer 2
              Virtual Private Networks (L2VPNs)", RFC 6074,
              DOI 10.17487/RFC6074, January 2011,
              <https://www.rfc-editor.org/info/rfc6074>.

   [RFC6241]  Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
              and A. Bierman, Ed., "Network Configuration Protocol
              (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
              <https://www.rfc-editor.org/info/rfc6241>.

   [RFC6242]  Wasserman, M., "Using the NETCONF Protocol over Secure
              Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
              <https://www.rfc-editor.org/info/rfc6242>.

   [RFC6991]  Schoenwaelder, J., Ed., "Common YANG Data Types",
              RFC 6991, DOI 10.17487/RFC6991, July 2013,
              <https://www.rfc-editor.org/info/rfc6991>.

   [RFC7432]  Sajassi, A., Ed., Aggarwal, R., Bitar, N., Isaac, A.,
              Uttaro, J., Drake, J., and W. Henderickx, "BGP MPLS-Based
              Ethernet VPN", RFC 7432, DOI 10.17487/RFC7432, February
              2015, <https://www.rfc-editor.org/info/rfc7432>.

   [RFC7623]  Sajassi, A., Ed., Salam, S., Bitar, N., Isaac, A., and W.
              Henderickx, "Provider Backbone Bridging Combined with
              Ethernet VPN (PBB-EVPN)", RFC 7623, DOI 10.17487/RFC7623,
              September 2015, <https://www.rfc-editor.org/info/rfc7623>.

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   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <https://www.rfc-editor.org/info/rfc7950>.

   [RFC8040]  Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
              Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
              <https://www.rfc-editor.org/info/rfc8040>.

   [RFC8077]  Martini, L., Ed. and G. Heron, Ed., "Pseudowire Setup and
              Maintenance Using the Label Distribution Protocol (LDP)",
              STD 84, RFC 8077, DOI 10.17487/RFC8077, February 2017,
              <https://www.rfc-editor.org/info/rfc8077>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8214]  Boutros, S., Sajassi, A., Salam, S., Drake, J., and J.
              Rabadan, "Virtual Private Wire Service Support in Ethernet
              VPN", RFC 8214, DOI 10.17487/RFC8214, August 2017,
              <https://www.rfc-editor.org/info/rfc8214>.

   [RFC8294]  Liu, X., Qu, Y., Lindem, A., Hopps, C., and L. Berger,
              "Common YANG Data Types for the Routing Area", RFC 8294,
              DOI 10.17487/RFC8294, December 2017,
              <https://www.rfc-editor.org/info/rfc8294>.

   [RFC8341]  Bierman, A. and M. Bjorklund, "Network Configuration
              Access Control Model", STD 91, RFC 8341,
              DOI 10.17487/RFC8341, March 2018,
              <https://www.rfc-editor.org/info/rfc8341>.

   [RFC8342]  Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
              and R. Wilton, "Network Management Datastore Architecture
              (NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
              <https://www.rfc-editor.org/info/rfc8342>.

   [RFC8365]  Sajassi, A., Ed., Drake, J., Ed., Bitar, N., Shekhar, R.,
              Uttaro, J., and W. Henderickx, "A Network Virtualization
              Overlay Solution Using Ethernet VPN (EVPN)", RFC 8365,
              DOI 10.17487/RFC8365, March 2018,
              <https://www.rfc-editor.org/info/rfc8365>.

   [RFC8466]  Wen, B., Fioccola, G., Ed., Xie, C., and L. Jalil, "A YANG
              Data Model for Layer 2 Virtual Private Network (L2VPN)
              Service Delivery", RFC 8466, DOI 10.17487/RFC8466, October
              2018, <https://www.rfc-editor.org/info/rfc8466>.

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11.2.  Informative References

   [I-D.ietf-bess-evpn-pref-df]
              Rabadan, J., Sathappan, S., Przygienda, T., Lin, W.,
              Drake, J., Sajassi, A., and S. Mohanty, "Preference-based
              EVPN DF Election", Work in Progress, Internet-Draft,
              draft-ietf-bess-evpn-pref-df-08, 23 September 2021,
              <https://www.ietf.org/archive/id/draft-ietf-bess-evpn-
              pref-df-08.txt>.

   [I-D.ietf-bess-evpn-yang]
              Brissette, P., Shah, H., Hussain, I., Tiruveedhula, K.,
              and J. Rabadan, "Yang Data Model for EVPN", Work in
              Progress, Internet-Draft, draft-ietf-bess-evpn-yang-07, 11
              March 2019, <https://www.ietf.org/archive/id/draft-ietf-
              bess-evpn-yang-07.txt>.

   [I-D.ietf-idr-bgp-model]
              Jethanandani, M., Patel, K., Hares, S., and J. Haas, "BGP
              YANG Model for Service Provider Networks", Work in
              Progress, Internet-Draft, draft-ietf-idr-bgp-model-11, 11
              July 2021, <https://www.ietf.org/archive/id/draft-ietf-
              idr-bgp-model-11.txt>.

   [I-D.ietf-teas-enhanced-vpn]
              Dong, J., Bryant, S., Li, Z., Miyasaka, T., and Y. Lee, "A
              Framework for Enhanced Virtual Private Network (VPN+)
              Services", Work in Progress, Internet-Draft, draft-ietf-
              teas-enhanced-vpn-08, 12 July 2021,
              <https://www.ietf.org/archive/id/draft-ietf-teas-enhanced-
              vpn-08.txt>.

   [I-D.ietf-teas-ietf-network-slices]
              Farrel, A., Gray, E., Drake, J., Rokui, R., Homma, S.,
              Makhijani, K., Contreras, L. M., and J. Tantsura,
              "Framework for IETF Network Slices", Work in Progress,
              Internet-Draft, draft-ietf-teas-ietf-network-slices-04, 23
              August 2021, <https://www.ietf.org/archive/id/draft-ietf-
              teas-ietf-network-slices-04.txt>.

   [IEEE802.1AX]
              "Link Aggregation", IEEE Std 802.1AX-2020, 2020.

   [PYANG]    "pyang", November 2020,
              <https://github.com/mbj4668/pyang>.

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   [RFC2507]  Degermark, M., Nordgren, B., and S. Pink, "IP Header
              Compression", RFC 2507, DOI 10.17487/RFC2507, February
              1999, <https://www.rfc-editor.org/info/rfc2507>.

   [RFC2508]  Casner, S. and V. Jacobson, "Compressing IP/UDP/RTP
              Headers for Low-Speed Serial Links", RFC 2508,
              DOI 10.17487/RFC2508, February 1999,
              <https://www.rfc-editor.org/info/rfc2508>.

   [RFC3032]  Rosen, E., Tappan, D., Fedorkow, G., Rekhter, Y.,
              Farinacci, D., Li, T., and A. Conta, "MPLS Label Stack
              Encoding", RFC 3032, DOI 10.17487/RFC3032, January 2001,
              <https://www.rfc-editor.org/info/rfc3032>.

   [RFC3545]  Koren, T., Casner, S., Geevarghese, J., Thompson, B., and
              P. Ruddy, "Enhanced Compressed RTP (CRTP) for Links with
              High Delay, Packet Loss and Reordering", RFC 3545,
              DOI 10.17487/RFC3545, July 2003,
              <https://www.rfc-editor.org/info/rfc3545>.

   [RFC3644]  Snir, Y., Ramberg, Y., Strassner, J., Cohen, R., and B.
              Moore, "Policy Quality of Service (QoS) Information
              Model", RFC 3644, DOI 10.17487/RFC3644, November 2003,
              <https://www.rfc-editor.org/info/rfc3644>.

   [RFC4446]  Martini, L., "IANA Allocations for Pseudowire Edge to Edge
              Emulation (PWE3)", BCP 116, RFC 4446,
              DOI 10.17487/RFC4446, April 2006,
              <https://www.rfc-editor.org/info/rfc4446>.

   [RFC4448]  Martini, L., Ed., Rosen, E., El-Aawar, N., and G. Heron,
              "Encapsulation Methods for Transport of Ethernet over MPLS
              Networks", RFC 4448, DOI 10.17487/RFC4448, April 2006,
              <https://www.rfc-editor.org/info/rfc4448>.

   [RFC4553]  Vainshtein, A., Ed. and YJ. Stein, Ed., "Structure-
              Agnostic Time Division Multiplexing (TDM) over Packet
              (SAToP)", RFC 4553, DOI 10.17487/RFC4553, June 2006,
              <https://www.rfc-editor.org/info/rfc4553>.

   [RFC4618]  Martini, L., Rosen, E., Heron, G., and A. Malis,
              "Encapsulation Methods for Transport of PPP/High-Level
              Data Link Control (HDLC) over MPLS Networks", RFC 4618,
              DOI 10.17487/RFC4618, September 2006,
              <https://www.rfc-editor.org/info/rfc4618>.

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   [RFC4619]  Martini, L., Ed., Kawa, C., Ed., and A. Malis, Ed.,
              "Encapsulation Methods for Transport of Frame Relay over
              Multiprotocol Label Switching (MPLS) Networks", RFC 4619,
              DOI 10.17487/RFC4619, September 2006,
              <https://www.rfc-editor.org/info/rfc4619>.

   [RFC4664]  Andersson, L., Ed. and E. Rosen, Ed., "Framework for Layer
              2 Virtual Private Networks (L2VPNs)", RFC 4664,
              DOI 10.17487/RFC4664, September 2006,
              <https://www.rfc-editor.org/info/rfc4664>.

   [RFC4717]  Martini, L., Jayakumar, J., Bocci, M., El-Aawar, N.,
              Brayley, J., and G. Koleyni, "Encapsulation Methods for
              Transport of Asynchronous Transfer Mode (ATM) over MPLS
              Networks", RFC 4717, DOI 10.17487/RFC4717, December 2006,
              <https://www.rfc-editor.org/info/rfc4717>.

   [RFC4816]  Malis, A., Martini, L., Brayley, J., and T. Walsh,
              "Pseudowire Emulation Edge-to-Edge (PWE3) Asynchronous
              Transfer Mode (ATM) Transparent Cell Transport Service",
              RFC 4816, DOI 10.17487/RFC4816, February 2007,
              <https://www.rfc-editor.org/info/rfc4816>.

   [RFC4842]  Malis, A., Pate, P., Cohen, R., Ed., and D. Zelig,
              "Synchronous Optical Network/Synchronous Digital Hierarchy
              (SONET/SDH) Circuit Emulation over Packet (CEP)",
              RFC 4842, DOI 10.17487/RFC4842, April 2007,
              <https://www.rfc-editor.org/info/rfc4842>.

   [RFC4863]  Martini, L. and G. Swallow, "Wildcard Pseudowire Type",
              RFC 4863, DOI 10.17487/RFC4863, May 2007,
              <https://www.rfc-editor.org/info/rfc4863>.

   [RFC4901]  Ash, J., Ed., Hand, J., Ed., and A. Malis, Ed., "Protocol
              Extensions for Header Compression over MPLS", RFC 4901,
              DOI 10.17487/RFC4901, June 2007,
              <https://www.rfc-editor.org/info/rfc4901>.

   [RFC5086]  Vainshtein, A., Ed., Sasson, I., Metz, E., Frost, T., and
              P. Pate, "Structure-Aware Time Division Multiplexed (TDM)
              Circuit Emulation Service over Packet Switched Network
              (CESoPSN)", RFC 5086, DOI 10.17487/RFC5086, December 2007,
              <https://www.rfc-editor.org/info/rfc5086>.

   [RFC5087]  Stein, Y(J)., Shashoua, R., Insler, R., and M. Anavi,
              "Time Division Multiplexing over IP (TDMoIP)", RFC 5087,
              DOI 10.17487/RFC5087, December 2007,
              <https://www.rfc-editor.org/info/rfc5087>.

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   [RFC5143]  Malis, A., Brayley, J., Shirron, J., Martini, L., and S.
              Vogelsang, "Synchronous Optical Network/Synchronous
              Digital Hierarchy (SONET/SDH) Circuit Emulation Service
              over MPLS (CEM) Encapsulation", RFC 5143,
              DOI 10.17487/RFC5143, February 2008,
              <https://www.rfc-editor.org/info/rfc5143>.

   [RFC5795]  Sandlund, K., Pelletier, G., and L-E. Jonsson, "The RObust
              Header Compression (ROHC) Framework", RFC 5795,
              DOI 10.17487/RFC5795, March 2010,
              <https://www.rfc-editor.org/info/rfc5795>.

   [RFC5880]  Katz, D. and D. Ward, "Bidirectional Forwarding Detection
              (BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010,
              <https://www.rfc-editor.org/info/rfc5880>.

   [RFC6307]  Black, D., Ed., Dunbar, L., Ed., Roth, M., and R. Solomon,
              "Encapsulation Methods for Transport of Fibre Channel
              Traffic over MPLS Networks", RFC 6307,
              DOI 10.17487/RFC6307, April 2012,
              <https://www.rfc-editor.org/info/rfc6307>.

   [RFC6624]  Kompella, K., Kothari, B., and R. Cherukuri, "Layer 2
              Virtual Private Networks Using BGP for Auto-Discovery and
              Signaling", RFC 6624, DOI 10.17487/RFC6624, May 2012,
              <https://www.rfc-editor.org/info/rfc6624>.

   [RFC7209]  Sajassi, A., Aggarwal, R., Uttaro, J., Bitar, N.,
              Henderickx, W., and A. Isaac, "Requirements for Ethernet
              VPN (EVPN)", RFC 7209, DOI 10.17487/RFC7209, May 2014,
              <https://www.rfc-editor.org/info/rfc7209>.

   [RFC7297]  Boucadair, M., Jacquenet, C., and N. Wang, "IP
              Connectivity Provisioning Profile (CPP)", RFC 7297,
              DOI 10.17487/RFC7297, July 2014,
              <https://www.rfc-editor.org/info/rfc7297>.

   [RFC7951]  Lhotka, L., "JSON Encoding of Data Modeled with YANG",
              RFC 7951, DOI 10.17487/RFC7951, August 2016,
              <https://www.rfc-editor.org/info/rfc7951>.

   [RFC8309]  Wu, Q., Liu, W., and A. Farrel, "Service Models
              Explained", RFC 8309, DOI 10.17487/RFC8309, January 2018,
              <https://www.rfc-editor.org/info/rfc8309>.

   [RFC8340]  Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
              BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
              <https://www.rfc-editor.org/info/rfc8340>.

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   [RFC8343]  Bjorklund, M., "A YANG Data Model for Interface
              Management", RFC 8343, DOI 10.17487/RFC8343, March 2018,
              <https://www.rfc-editor.org/info/rfc8343>.

   [RFC8345]  Clemm, A., Medved, J., Varga, R., Bahadur, N.,
              Ananthakrishnan, H., and X. Liu, "A YANG Data Model for
              Network Topologies", RFC 8345, DOI 10.17487/RFC8345, March
              2018, <https://www.rfc-editor.org/info/rfc8345>.

   [RFC8446]  Rescorla, E., "The Transport Layer Security (TLS) Protocol
              Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
              <https://www.rfc-editor.org/info/rfc8446>.

   [RFC8453]  Ceccarelli, D., Ed. and Y. Lee, Ed., "Framework for
              Abstraction and Control of TE Networks (ACTN)", RFC 8453,
              DOI 10.17487/RFC8453, August 2018,
              <https://www.rfc-editor.org/info/rfc8453>.

   [RFC8519]  Jethanandani, M., Agarwal, S., Huang, L., and D. Blair,
              "YANG Data Model for Network Access Control Lists (ACLs)",
              RFC 8519, DOI 10.17487/RFC8519, March 2019,
              <https://www.rfc-editor.org/info/rfc8519>.

   [RFC8584]  Rabadan, J., Ed., Mohanty, S., Ed., Sajassi, A., Drake,
              J., Nagaraj, K., and S. Sathappan, "Framework for Ethernet
              VPN Designated Forwarder Election Extensibility",
              RFC 8584, DOI 10.17487/RFC8584, April 2019,
              <https://www.rfc-editor.org/info/rfc8584>.

   [RFC8792]  Watsen, K., Auerswald, E., Farrel, A., and Q. Wu,
              "Handling Long Lines in Content of Internet-Drafts and
              RFCs", RFC 8792, DOI 10.17487/RFC8792, June 2020,
              <https://www.rfc-editor.org/info/rfc8792>.

   [RFC8960]  Saad, T., Raza, K., Gandhi, R., Liu, X., and V. Beeram, "A
              YANG Data Model for MPLS Base", RFC 8960,
              DOI 10.17487/RFC8960, December 2020,
              <https://www.rfc-editor.org/info/rfc8960>.

   [RFC8969]  Wu, Q., Ed., Boucadair, M., Ed., Lopez, D., Xie, C., and
              L. Geng, "A Framework for Automating Service and Network
              Management with YANG", RFC 8969, DOI 10.17487/RFC8969,
              January 2021, <https://www.rfc-editor.org/info/rfc8969>.

Appendix A.  Examples

   This section includes a non-exhaustive list of examples to illustrate
   the use of the L2NM.

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   In the following subsections, only the content of the message bodies
   is shown using JSON notations [RFC7951].

   The examples use the folding defined in [RFC8792] for long lines.

A.1.  BGP-based VPLS

   This section provides an example to illustrate how the L2NM can be
   used to mange BGP-based VPLS.  We consider the sample VPLS service
   delivered using the architecture depicted in Figure 23.  In
   accordance with [RFC4761], we assume that a full mesh is established
   between all PEs.  The details about such full mesh are not detailed
   here.

                    +-----+      +--------------+   +-----+
       +----+       | PE1 |======|              |===| PE3 |       +----+
       | CE1+-------+     |      |              |   |     +-------+ CE3|
       +----+       +-----+      |              |   +-----+       +----+
                                 |     Core     |
       +----+       +-----+      |              |   +-----+       +----+
       |CE2 +-------+     |      |              |   |     +-------+ CE4|
       +----+       | PE2 |======|              |===| PE4 |       +----+
                    +-----+      +--------------+   +-----+

                     Figure 23: An Example of VPLS

   Figure 24 show an example of a message body used to configured a VPLS
   instance using the L2NM.  In this example, BGP is used for both auto-
   discovery and signaling.  The 'signaling-type' data node is set to
   'vpn-common:bgp-signaling'.

=============== NOTE: '\' line wrapping per RFC 8792 ================

{
  "ietf-l2vpn-ntw:l2vpn-ntw": {
    "vpn-services": {
      "vpn-service": [
        {
          "vpn-id": "vpls7714825356",
          "vpn-description": "Sample BGP-based VPLS",
          "customer-name": "customer-7714825356",
          "vpn-type": "ietf-vpn-common:vpls",
          "bgp-ad-enabled": true,
          "signaling-type": "ietf-vpn-common:bgp-signaling",
          "global-parameters-profiles": {
            "global-parameters-profile": [

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              {
                "profile-id": "simple-profile",
                "local-autonomous-system": 65535,
                "svc-mtu": 1518,
                "rd-suffix": 1,
                "vpn-target": [
                  {
                    "id": 1,
                    "route-targets": [
                      {
                        "route-target": "0:65535:1"
                      }
                    ],
                    "route-target-type": "both"
                  }
                ]
              }
            ]
          },
          "vpn-nodes": {
            "vpn-node": [
              {
                "vpn-node-id": "pe1",
                "ne-id": "198.51.100.1",
                "active-global-parameters-profiles": {
                  "global-parameters-profile": [
                    {
                      "profile-id": "simple-profile"
                    }
                  ]
                },
                "bgp-auto-discovery": {
                  "vpn-id": "1"
                },
                "signaling-option": {
                  "pw-encapsulation-type": "iana-bgp-l2-encaps:ethernet\
-tagged-mode",
                  "vpls-instance": {
                    "vpls-edge-id": 1,
                    "vpls-edge-id-range": 100
                  }
                },
                "vpn-network-accesses": {
                  "vpn-network-access": [
                    {
                      "id": "1/1/1.1",
                      "interface-id": "1/1/1",
                      "description": "Interface to CE1",

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                      "global-parameters-profile": "simple-profile",
                      "status": {
                        "admin-status": {
                          "status": "ietf-vpn-common:admin-up"
                        }
                      },
                      "connection": {
                        "encapsulation": {
                          "encap-type": "ietf-vpn-common:dot1q",
                          "dot1q": {
                            "cvlan-id": 1
                          }
                        }
                      }
                    }
                  ]
                }
              },
              {
                "vpn-node-id": "pe2",
                "ne-id": "198.51.100.2",
                "active-global-parameters-profiles": {
                  "global-parameters-profile": [
                    {
                      "profile-id": "simple-profile"
                    }
                  ]
                },
                "bgp-auto-discovery": {
                  "vpn-id": "1"
                },
                "signaling-option": {
                  "pw-encapsulation-type": "iana-bgp-l2-encaps:ethernet\
-tagged-mode",
                  "vpls-instance": {
                    "vpls-edge-id": 2,
                    "vpls-edge-id-range": 100
                  }
                },
                "vpn-network-accesses": {
                  "vpn-network-access": [
                    {
                      "id": "1/1/1.1",
                      "interface-id": "1/1/1",
                      "description": "Interface to CE2",
                      "global-parameters-profile": "simple-profile",
                      "status": {
                        "admin-status": {

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                          "status": "ietf-vpn-common:admin-up"
                        }
                      },
                      "connection": {
                        "encapsulation": {
                          "encap-type": "ietf-vpn-common:dot1q",
                          "dot1q": {
                            "cvlan-id": 1
                          }
                        }
                      }
                    }
                  ]
                }
              },
              {
                "vpn-node-id": "pe3",
                "ne-id": "198.51.100.3",
                "active-global-parameters-profiles": {
                  "global-parameters-profile": [
                    {
                      "profile-id": "simple-profile"
                    }
                  ]
                },
                "bgp-auto-discovery": {
                  "vpn-id": "1"
                },
                "signaling-option": {
                  "pw-encapsulation-type": "iana-bgp-l2-encaps:ethernet\
-tagged-mode",
                  "vpls-instance": {
                    "vpls-edge-id": 3,
                    "vpls-edge-id-range": 100
                  }
                },
                "vpn-network-accesses": {
                  "vpn-network-access": [
                    {
                      "id": "1/1/1.1",
                      "interface-id": "1/1/1",
                      "description": "Interface to CE3",
                      "global-parameters-profile": "simple-profile",
                      "status": {
                        "admin-status": {
                          "status": "ietf-vpn-common:admin-up"
                        }
                      },

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                      "connection": {
                        "encapsulation": {
                          "encap-type": "ietf-vpn-common:dot1q",
                          "dot1q": {
                            "cvlan-id": 1
                          }
                        }
                      }
                    }
                  ]
                }
              },
              {
                "vpn-node-id": "pe4",
                "ne-id": "198.51.100.4",
                "active-global-parameters-profiles": {
                  "global-parameters-profile": [
                    {
                      "profile-id": "simple-profile"
                    }
                  ]
                },
                "bgp-auto-discovery": {
                  "vpn-id": "1"
                },
                "signaling-option": {
                  "pw-encapsulation-type": "iana-bgp-l2-encaps:ethernet\
-tagged-mode",
                  "vpls-instance": {
                    "vpls-edge-id": 4,
                    "vpls-edge-id-range": 100
                  }
                },
                "vpn-network-accesses": {
                  "vpn-network-access": [
                    {
                      "id": "1/1/1.1",
                      "interface-id": "1/1/1",
                      "description": "Interface to CE4",
                      "global-parameters-profile": "simple-profile",
                      "status": {
                        "admin-status": {
                          "status": "ietf-vpn-common:admin-up"
                        }
                      },
                      "connection": {
                        "encapsulation": {
                          "encap-type": "ietf-vpn-common:dot1q",

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                          "dot1q": {
                            "cvlan-id": 1
                          }
                        }
                      }
                    }
                  ]
                }
              }
            ]
          }
        }
      ]
    }
  }
}

Figure 24: Example of L2NM Message Body to Configure a BGP-based VPLS

A.2.  BGP-based VPWS with LDP Signaling

   Let's consider the simple architecture depicted in Figure 25 to offer
   a VPWS between CE1 and CE2.  The service uses BGP for auto-discovery
   and LDP for signaling.

                    +-----+      +--------------+   +-----+
       +----+       | PE1 |======|              |===| PE2 |       +----+
       | CE1+-------+     |      |     Core     |   |     +-------+ CE2|
       +----+       +-----+      +--------------+   +-----+       +----+
              site1                                          site2

                     Figure 25: An Example of VPLS

   {
     "ietf-l2vpn-ntw:l2vpn-ntw": {
       "vpn-services": {
         "vpn-service": [
           {
             "vpn-id": "vpws12345",
             "vpn-description": "Sample VPWS",
             "customer-name": "customer-12345",
             "vpn-type": "ietf-vpn-common:vpws",
             "bgp-ad-enabled": true,
             "signaling-type": "ietf-vpn-common:ldp-signaling",
             "global-parameters-profiles": {
               "global-parameters-profile": [

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                 {
                   "profile-id": "simple-profile",
                   "local-autonomous-system": 65550,
                   "rd-auto": {
                     "auto": [
                       null
                     ]
                   },
                   "vpn-target": [
                     {
                       "id": 1,
                       "route-targets": [
                         {
                           "route-target": "0:65535:1"
                         }
                       ],
                       "route-target-type": "both"
                     }
                   ]
                 }
               ]
             },
             "vpn-nodes": {
               "vpn-node": [
                 {
                   "vpn-node-id": "pe1",
                   "ne-id": "2001:db8:100::1",
                   "active-global-parameters-profiles": {
                     "global-parameters-profile": [
                       {
                         "profile-id": "simple-profile"
                       }
                     ]
                   },
                   "bgp-auto-discovery": {
                     "vpn-id": "587"
                   },
                   "signaling-option": {
                     "advertise-mtu": true,
                     "ldp-or-l2tp": {
                       "saii": 1,
                       "remote-targets": [
                         {
                           "taii": 2
                         }
                       ],
                       "pw-type": "ethernet"
                     }

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                   },
                   "vpn-network-accesses": {
                     "vpn-network-access": [
                       {
                         "id": "1/1/1.1",
                         "interface-id": "1/1/1",
                         "description": "Interface to CE1",
                         "global-parameters-profile": "simple-profile",
                         "status": {
                           "admin-status": {
                             "status": "ietf-vpn-common:admin-up"
                           }
                         }
                       }
                     ]
                   }
                 },
                 {
                   "vpn-node-id": "pe2",
                   "ne-id": "2001:db8:200::1",
                   "active-global-parameters-profiles": {
                     "global-parameters-profile": [
                       {
                         "profile-id": "simple-profile"
                       }
                     ]
                   },
                   "bgp-auto-discovery": {
                     "vpn-id": "587"
                   },
                   "signaling-option": {
                     "advertise-mtu": true,
                     "ldp-or-l2tp": {
                       "saii": 2,
                       "remote-targets": [
                         {
                           "taii": 1
                         }
                       ],
                       "pw-type": "ethernet"
                     }
                   },
                   "vpn-network-accesses": {
                     "vpn-network-access": [
                       {
                         "id": "5/1/1.1",
                         "interface-id": "5/1/1",
                         "description": "Interface to CE2",

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                         "global-parameters-profile": "simple-profile",
                         "status": {
                           "admin-status": {
                             "status": "ietf-vpn-common:admin-up"
                           }
                         }
                       }
                     ]
                   }
                 }
               ]
             }
           }
         ]
       }
     }
   }

      Figure 26: Example of L2NM Message Body to Configure a BGP-based
                          VPWS with LDP Signaling

A.3.  LDP-based VPLS

   This section provides an example to illustrate how the L2NM can be
   used to manage a VPLS with LDP signaling.  The connectivity between
   the CE and the PE is direct using Dot1q encapsulation.  We consider
   the sample service delivered using the architecture depicted in
   Figure 27.

                    +-----------  VPLS "1543" ------------+

                    +-----+      +--------------+   +-----+
        +----+      | PE1 |======|              |===| PE2 |       +----+
        | CE1 +-----+"450"|      |     MPLS     |   |"451"+-------+ CE2|
        +----+      +-----+      |              |   +-----+       +----+
                                 |     Core     |
                                 +--------------+

                  Figure 27: An Example of VPLS topology

   Figure 28 shows how the L2NM is used to instruct both PE1 and PE2 to
   use the targeted LDP session between them to establish the VPLS
   "1543" between the ends.  A single VPN service is created for this
   purpose.  Additionally, two VPN Nodes and each with a corresponding
   VPN network access is also created.

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 =============== NOTE: '\' line wrapping per RFC 8792 ================

 {
   "ietf-l2vpn-ntw:l2vpn-ntw": {
     "vpn-services": {
       "vpn-service": [
         {
           "vpn-id": "450",
           "vpn-name": "CORPO-EXAMPLE",
           "vpn-description": "SEDE_CENTRO_450",
           "customer-name": "EXAMPLE",
           "vpn-type": "ietf-vpn-common:vpls",
           "vpn-service-topology": "ietf-vpn-common:hub-spoke",
           "bgp-ad-enabled": false,
           "signaling-type": "ietf-vpn-common:ldp-signaling",
           "global-parameters-profiles": {
             "global-parameters-profile": [
               {
                 "profile-id": "simple-profile",
                 "ce-vlan-preservation": true,
                 "ce-vlan-cos-preservation": true
               }
             ]
           },
           "vpn-nodes": {
             "vpn-node": [
               {
                 "vpn-node-id": "450",
                 "description": "SEDE_CENTRO_450",
                 "ne-id": "2001:db8:5::1",
                 "role": "ietf-vpn-common:hub-role",
                 "status": {
                   "admin-status": {
                     "status": "ietf-vpn-common:admin-up"
                   }
                 },
                 "active-global-parameters-profiles": {
                   "global-parameters-profile": [
                     {
                       "profile-id": "simple-profile"
                     }
                   ]
                 },
                 "signaling-option": {
                   "ldp-or-l2tp": {
                     "t-ldp-pw-type": "vpls-type",
                     "pw-peer-list": [
                       {

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                         "peer-addr": "2001:db8:50::1",
                         "vc-id": "1543"
                       }
                     ]
                   }
                 },
                 "vpn-network-accesses": {
                   "vpn-network-access": [
                     {
                       "id": "4508671287",
                       "description": "VPN_450_SNA",
                       "interface-id": "gigabithethernet0/0/1",
                       "status": {
                         "admin-status": {
                           "status": "ietf-vpn-common:admin-up"
                         }
                       },
                       "connection": {
                         "l2-termination-point": "550",
                         "encapsulation": {
                           "encap-type": "ietf-vpn-common:dot1q",
                           "dot1q": {
                             "tag-type": "ietf-vpn-common:c-vlan",
                             "cvlan-id": 550
                           }
                         }
                       },
                       "service": {
                         "mtu": 1550,
                         "svc-inbound-bandwidth": {
                           "inbound-bandwidth": [
                             {
                               "bw-type": "ietf-vpn-common:bw-per-\
 service",
                               "cir": "20480000"
                             }
                           ]
                         },
                         "svc-outbound-bandwidth": {
                           "outbound-bandwidth": [
                             {
                               "bw-type": "ietf-vpn-common:bw-per-port",
                               "cir": "20480000"
                             }
                           ]
                         },
                         "qos": {
                           "qos-profile": {

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                             "qos-profile": [
                               {
                                 "profile": "QoS_Profile_A",
                                 "direction": "ietf-vpn-common:both"
                               }
                             ]
                           }
                         }
                       }
                     }
                   ]
                 }
               },
               {
                 "vpn-node-id": "451",
                 "description": "SEDE_CHAPINERO_451",
                 "ne-id": "2001:db8:50::1",
                 "role": "ietf-vpn-common:spoke-role",
                 "status": {
                   "admin-status": {
                     "status": "ietf-vpn-common:admin-up"
                   }
                 },
                 "active-global-parameters-profiles": {
                   "global-parameters-profile": [
                     {
                       "profile-id": "simple-profile"
                     }
                   ]
                 },
                 "signaling-option": {
                   "ldp-or-l2tp": {
                     "t-ldp-pw-type": "vpls-type",
                     "pw-peer-list": [
                       {
                         "peer-addr": "2001:db8:5::1",
                         "vc-id": "1543"
                       }
                     ]
                   }
                 },
                 "vpn-network-accesses": {
                   "vpn-network-access": [
                     {
                       "id": "4508671288",
                       "description": "VPN_450_SNA",
                       "interface-id": "gigabithethernet0/0/1",
                       "status": {

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                         "admin-status": {
                           "status": "ietf-vpn-common:admin-up"
                         }
                       },
                       "connection": {
                         "l2-termination-point": "550",
                         "encapsulation": {
                           "encap-type": "ietf-vpn-common:dot1q",
                           "dot1q": {
                             "tag-type": "ietf-vpn-common:c-vlan",
                             "cvlan-id": 550
                           }
                         }
                       },
                       "service": {
                         "mtu": 1550,
                         "svc-inbound-bandwidth": {
                           "inbound-bandwidth": [
                             {
                               "bw-type": "ietf-vpn-common:bw-per-\
 service",
                               "cir": "20480000"
                             }
                           ]
                         },
                         "svc-outbound-bandwidth": {
                           "outbound-bandwidth": [
                             {
                               "bw-type": "ietf-vpn-common:bw-per-port",
                               "cir": "20480000"
                             }
                           ]
                         },
                         "qos": {
                           "qos-profile": {
                             "qos-profile": [
                               {
                                 "profile": "QoS_Profile_A",
                                 "direction": "ietf-vpn-common:both"
                               }
                             ]
                           }
                         }
                       }
                     }
                   ]
                 }
               }

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             ]
           }
         }
       ]
     }
   }
 }

       Figure 28: Example of L2NM Message Body for LDP-based VPLS

A.4.  VPWS-EVPN Service Instance

   Figure 29 depictes a sample architecture to offer VPWS-EVPN service
   between CE1 and CE2.  Both CEs are multi-homed.  BGP sessions are
   maintained between these PEs as per [RFC8214].  In this EVPN
   instance, an All-Active redundancy mode is used.

                    |<--------- EVPN Instance ----------->|
                    |                                     |
              |     V                                     V  |
              |     +-----+      +--------------+   +-----+  |
       +----+ |     | PE1 |======|              |===| PE3 |  |    +----+
       |    +-------+     |      |              |   |     +-------+    |
       |    | |     +-----+      |              |   +-----+  |    |    |
       | CE1| |                  |     Core     |            |    |CE2 |
       |    | |     +-----+      |              |   +-----+  |    |    |
       |    +-------+     |      |              |   |     +-------+    |
       +----+ |     | PE2 |======|              |===| PE4 |  |    +----+
            ^  ESI1 +-----+      +--------------+   +-----+  ESI2    ^
            |                                                        |
            |<---------------- Emulated Service -------------------->|

                   Figure 29: An Example of VPWS-EVPN

   Let's first suppose that the following ES was created (Figure 30).

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   =============== NOTE: '\' line wrapping per RFC 8792 ================

   {
     "ietf-ethernet-segment:ethernet-segments": {
       "ethernet-segment": [
         {
           "name": "esi1",
           "ethernet-segment-identifier": "00:11:11:11:11:11:11:\
   11:11:11",
           "esi-redundancy-mode": "all-active"
         },
         {
           "name": "esi2",
           "ethernet-segment-identifier": "00:22:22:22:22:22:22:\
   22:22:22",
           "esi-redundancy-mode": "all-active"
         }
       ]
     }
   }

      Figure 30: Example of L2NM Message Body to Configure an Ethernet
                                  Segment

   Figure 29 shows a simplified configuration to illustrate the use of
   the L2NM to configured VPWS-EVPN instance.

   {
     "ietf-l2vpn-ntw:l2vpn-ntw": {
       "vpn-services": {
         "vpn-service": [
           {
             "vpn-id": "vpws15432855",
             "vpn-description": "Sample VPWS-EVPN",
             "customer-name": "customer_15432855",
             "vpn-type": "ietf-vpn-common:vpws-evpn",
             "bgp-ad-enabled": true,
             "signaling-type": "ietf-vpn-common:bgp-signaling",
             "global-parameters-profiles": {
               "global-parameters-profile": [
                 {
                   "profile-id": "simple-profile",
                   "local-autonomous-system": 65535,
                   "rd-suffix": 1,
                   "vpn-target": [
                     {
                       "id": 1,
                       "route-targets": [

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                         {
                           "route-target": "0:65535:1"
                         }
                       ],
                       "route-target-type": "both"
                     }
                   ]
                 }
               ]
             },
             "vpn-nodes": {
               "vpn-node": [
                 {
                   "vpn-node-id": "pe1",
                   "ne-id": "198.51.100.1",
                   "active-global-parameters-profiles": {
                     "global-parameters-profile": [
                       {
                         "profile-id": "simple-profile"
                       }
                     ]
                   },
                   "vpn-network-accesses": {
                     "vpn-network-access": [
                       {
                         "id": "1/1/1.1",
                         "interface-id": "1/1/1",
                         "description": "Interface to CE1",
                         "global-parameters-profile": "simple-profile",
                         "status": {
                           "admin-status": {
                             "status": "ietf-vpn-common:admin-up"
                           }
                         },
                         "connection": {
                           "encapsulation": {
                             "encap-type": "ietf-vpn-common:dot1q",
                             "dot1q": {
                               "cvlan-id": 1
                             }
                           }
                         },
                         "vpws-service-instance": {
                           "local-vpws-service-instance": 1111,
                           "remote-vpws-service-instance": 1112
                         },
                         "group": [
                           {

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                             "group-id": "gr1",
                             "ethernet-segment-identifier": "esi1"
                           }
                         ]
                       }
                     ]
                   }
                 },
                 {
                   "vpn-node-id": "pe2",
                   "ne-id": "198.51.100.2",
                   "active-global-parameters-profiles": {
                     "global-parameters-profile": [
                       {
                         "profile-id": "simple-profile"
                       }
                     ]
                   },
                   "vpn-network-accesses": {
                     "vpn-network-access": [
                       {
                         "id": "1/1/1.1",
                         "interface-id": "1/1/1",
                         "description": "Interface to CE1",
                         "global-parameters-profile": "simple-profile",
                         "status": {
                           "admin-status": {
                             "status": "ietf-vpn-common:admin-up"
                           }
                         },
                         "connection": {
                           "encapsulation": {
                             "encap-type": "ietf-vpn-common:dot1q",
                             "dot1q": {
                               "cvlan-id": 1
                             }
                           }
                         },
                         "vpws-service-instance": {
                           "local-vpws-service-instance": 1111,
                           "remote-vpws-service-instance": 1112
                         },
                         "group": [
                           {
                             "group-id": "gr1",
                             "ethernet-segment-identifier": "esi1"
                           }
                         ]

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                       }
                     ]
                   }
                 },
                 {
                   "vpn-node-id": "pe3",
                   "ne-id": "198.51.100.3",
                   "active-global-parameters-profiles": {
                     "global-parameters-profile": [
                       {
                         "profile-id": "simple-profile"
                       }
                     ]
                   },
                   "vpn-network-accesses": {
                     "vpn-network-access": [
                       {
                         "id": "1/1/1.1",
                         "interface-id": "1/1/1",
                         "description": "Interface to CE2",
                         "global-parameters-profile": "simple-profile",
                         "status": {
                           "admin-status": {
                             "status": "ietf-vpn-common:admin-up"
                           }
                         },
                         "connection": {
                           "encapsulation": {
                             "encap-type": "ietf-vpn-common:dot1q",
                             "dot1q": {
                               "cvlan-id": 1
                             }
                           }
                         },
                         "vpws-service-instance": {
                           "local-vpws-service-instance": 1112,
                           "remote-vpws-service-instance": 1111
                         },
                         "group": [
                           {
                             "group-id": "gr1",
                             "ethernet-segment-identifier": "esi2"
                           }
                         ]
                       }
                     ]
                   }
                 },

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                 {
                   "vpn-node-id": "pe4",
                   "ne-id": "198.51.100.4",
                   "active-global-parameters-profiles": {
                     "global-parameters-profile": [
                       {
                         "profile-id": "simple-profile"
                       }
                     ]
                   },
                   "vpn-network-accesses": {
                     "vpn-network-access": [
                       {
                         "id": "1/1/1.1",
                         "interface-id": "1/1/1",
                         "description": "Interface to CE2",
                         "global-parameters-profile": "simple-profile",
                         "status": {
                           "admin-status": {
                             "status": "ietf-vpn-common:admin-up"
                           }
                         },
                         "connection": {
                           "encapsulation": {
                             "encap-type": "ietf-vpn-common:dot1q",
                             "dot1q": {
                               "cvlan-id": 1
                             }
                           }
                         },
                         "vpws-service-instance": {
                           "local-vpws-service-instance": 1112,
                           "remote-vpws-service-instance": 1111
                         },
                         "group": [
                           {
                             "group-id": "gr1",
                             "ethernet-segment-identifier": "esi2"
                           }
                         ]
                       }
                     ]
                   }
                 }
               ]
             }
           }
         ]

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       }
     }
   }

      Figure 31: Example of L2NM Message Body to Configure a VPWS-EVPN
                                  Instance

A.5.  Automatic ESI Assignment

   This section provides an example to illustrate how the L2NM can be
   used to manage ESI auto-assignment.  We consider the sample EVPN
   service delivered using the architecture depicted in Figure 32.

              ES
              |     +-----+      +--------------+   +-----+
       +----+ |     | PE1 |======|              |===| PE3 |       +----+
       |    +-------+     |      |              |   |     +-------+ CE3|
       |    | |     +-----+      |              |   +-----+       +----+
       | CE1| |                  |     Core     |
       |    | |     +-----+      |              |   +-----+       +----+
       |    +-------+     |      |              |   |     +-------+ CE2|
       +----+ |     | PE2 |======|              |===| PE4 |       +----+
            LACP    +-----+      +--------------+   +-----+

           Figure 32: An Example of Automatic ESI Assignment

   Figure 33 and Figure 34 show how the L2NM is used to instruct both
   PE1 and PE2 to auto-assign the ESI to identify the ES used with CE1.
   In this example, we suppose that LACP is enabled and that a Type 1
   (T=0x01) is used as per Section 5 of [RFC7432].  Note that this
   example does not include all the details to configure the EVPN
   service, but focuses only on the ESI management part.

   {
     "ietf-ethernet-segment:ethernet-segments": {
       "ethernet-segment": [
         {
           "name": "esi1",
           "esi-type": "esi-type-1",
           "esi-redundancy-mode": "all-active"
         }
       ]
     }
   }

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      Figure 33: Example of L2NM Message Body to Auto-Assign Ethernet
                            Segment Identifiers

   {
     "ietf-l2vpn-ntw:l2vpn-ntw": {
       "ietf-l2vpn-ntw:vpn-services": {
         "vpn-service": [
           {
             "vpn-id": "auto-esi-lacp",
             "vpn-description": "Sample to illustrate auto-ESI",
             "vpn-type": "ietf-vpn-common:vpws-evpn",
             "vpn-nodes": {
               "vpn-node": [
                 {
                   "vpn-node-id": "pe1",
                   "ne-id": "198.51.100.1",
                   "vpn-network-accesses": {
                     "vpn-network-access": [
                       {
                         "id": "1/1/1.1",
                         "interface-id": "1/1/1",
                         "description": "Interface to CE1",
                         "status": {
                           "admin-status": {
                             "status": "ietf-vpn-common:admin-up"
                           }
                         },
                         "connection": {
                           "lag-interface": {
                             "lag-interface-id": "1",
                             "lacp": {
                               "lacp-state": true,
                               "system-id": "11:00:11:00:11:11",
                               "admin-key": 154
                             }
                           }
                         },
                         "group": [
                           {
                             "group-id": "gr1",
                             "ethernet-segment-identifier": "esi1"
                           }
                         ]
                       }
                     ]
                   }
                 },
                 {

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                   "vpn-node-id": "pe2",
                   "ne-id": "198.51.100.2",
                   "vpn-network-accesses": {
                     "vpn-network-access": [
                       {
                         "id": "2/2/2.5",
                         "interface-id": "2/2/2",
                         "description": "Interface to CE1",
                         "status": {
                           "admin-status": {
                             "status": "ietf-vpn-common:admin-up"
                           }
                         },
                         "connection": {
                           "lag-interface": {
                             "lag-interface-id": "1",
                             "lacp": {
                               "lacp-state": true,
                               "system-id": "11:00:11:00:11:11",
                               "admin-key": 154
                             }
                           }
                         },
                         "group": [
                           {
                             "group-id": "gr1",
                             "ethernet-segment-identifier": "esi1"
                           }
                         ]
                       }
                     ]
                   }
                 }
               ]
             }
           }
         ]
       }
     }
   }

     Figure 34: An Example of L2NM Message Body for ESI Auto-Assignment

   The auto-assigned ESI can be retrieved using, e.g., a GET RESTCONF
   method.  The assigned value will be then returned as shown in the
   'esi-auto' data node in Figure 35.

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   =============== NOTE: '\' line wrapping per RFC 8792 ================

   {
     "ietf-ethernet-segment:ethernet-segments": {
       "ethernet-segment": [
         {
           "name": "esi1",
           "ethernet-segment-identifier": "esi-type-1",
           "esi-auto": {
             "auto-ethernet-segment-identifier": "01:11:00:11:00:11:\
   11:9A:00:00"
           },
           "esi-redundancy-mode": "all-active"
         }
       ]
     }
   }

         Figure 35: An Example of L2NM Message Body to Retrieve the
                                Assigned ESI

A.6.  VPN Network Access Precedence

   In reference to the example depicted in Figure 36, an L2VPN service
   involves two VPN network accesses to sites that belong to the same
   customer.

   +--------------+
   |VPN-NODE      |
   |           +--+-------+
   |           | NET-ACC-1| Primary
   |           |          +------------------
   |           +--+-------+
   |              |
   |           +--+-------+
   |           | NET-ACC-2| Secondary
   |           |          +------------------
   |           +--+-------+
   |              |
   +--------------+

            Figure 36: Example of Multiple VPN Network Accesses

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   In order to tag one of these VPN network accesses as "primary" and
   the other one as "secondary", Figure 37 shows an excerpt of the
   corresponding L2NM configuration.  In such as configuration, both
   accesses are bound to the same "group-id" and the "precedence" data
   node set as function of the intended role of each access (primary or
   secondary).

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   {
     "ietf-l2vpn-ntw:l2vpn-ntw": {
       "vpn-services": {
         "vpn-service": [
           {
             "vpn-id": "Sample-Service",
             "vpn-nodes": {
               "vpn-node": [
                 {
                   "vpn-node-id": "VPN-NODE",
                   "vpn-network-accesses": {
                     "vpn-network-access": [
                       {
                         "id": "NET-ACC-1",
                         "connection": {
                           "bearer-reference": "br1"
                         },
                         "group": [
                           {
                             "group-id": "1",
                             "precedence": "primary"
                           }
                         ]
                       },
                       {
                         "id": "NET-ACC-2",
                         "connection": {
                           "bearer-reference": "br2"
                         },
                         "group": [
                           {
                             "group-id": "1",
                             "precedence": "secondary"
                           }
                         ]
                       }
                     ]
                   }
                 }
               ]
             }
           }
         ]
       }
     }
   }

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      Figure 37: Example of Message Body to Associate Priority Levels
                         with VPN Network Accesses

Appendix B.  Initial BGP Layer 2 Encapsulation Types

             Value Description                       Reference
             ===== ================================  =========
             1     Frame Relay                       [RFC4446]
             2     ATM AAL5 SDU VCC transport        [RFC4446]
             3     ATM transparent cell transport    [RFC4816]
             4     Ethernet (VLAN) Tagged Mode       [RFC4448]
             5     Ethernet Raw Mode                 [RFC4448]
             6     Cisco HDLC                        [RFC4618]
             7     PPP                               [RFC4618]
             8     SONET/SDH Circuit Emulation       [RFC4842]
                   Service
             9     ATM n-to-one VCC cell transport   [RFC4717]
             10    ATM n-to-one VPC cell transport   [RFC4717]
             11    IP Layer 2 Transport              [RFC3032]
             15    Frame Relay Port mode             [RFC4619]
             17    Structure-agnostic E1 over packet [RFC4553]
             18    Structure-agnostic T1 (DS1) over  [RFC4553]
                   packet
             19    VPLS                              [RFC4761]
             20    Structure-agnostic T3 (DS3) over  [RFC4553]
                   packet
             21    Nx64kbit/s Basic Service using    [RFC5086]
                   Structure-aware
             25    Frame Relay DLCI                  [RFC4619]
             40    Structure-agnostic E3 over packet [RFC4553]
             41    Octet-aligned payload for         [RFC4553]
                   Structure-agnostic DS1 circuits
             42    E1 Nx64kbit/s with CAS using      [RFC5086]
                   Structure-aware
             43    DS1 (ESF) Nx64kbit/s with CAS     [RFC5086]
                   using Structure-aware
             44    DS1 (SF) Nx64kbit/s with CAS      [RFC5086]
                   using Structure-aware

Appendix C.  Initial PW Types

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       PW Type Description                       Reference
       ======= ================================  =========
       0x0001  Frame Relay DLCI                  [RFC4619]
       0x0002  ATM AAL5 SDU VCC transport
       0x0003  ATM transparent cell transport    [RFC4717]
       0x0004  Ethernet Tagged Mode              [RFC4448]
       0x0005  Ethernet                          [RFC4448]
       0x0006  HDLC                              [RFC4618]
       0x0007  PPP                               [RFC4618]
       0x0008  SONET/SDH Circuit Emulation
               Service Over MPLS Encapsulation   [RFC5143]
       0x0009  ATM n-to-one VCC cell transport   [RFC4717]
       0x000A  ATM n-to-one VPC cell transport   [RFC4717]
       0x000B  IP Layer2 Transport               [RFC3032]
       0x000C  ATM one-to-one VCC Cell Mode      [RFC4717]
       0x000D  ATM one-to-one VPC Cell Mode      [RFC4717]
       0x000E  ATM AAL5 PDU VCC transport        [RFC4717]
       0x000F  Frame-Relay Port mode             [RFC4619]
       0x0010  SONET/SDH Circuit Emulation       [RFC4842]
               Reference Packet
       0x0011  Structure-agnostic E1 over        [RFC4553]
               Packet
       0x0012  Structure-agnostic T1 (DS1)       [RFC4553]
               over Packet
       0x0013  Structure-agnostic E3 over        [RFC4553]
               Packet
       0x0014  Structure-agnostic T3 (DS3)       [RFC4553]
               over Packet
       0x0015  CESoPSN basic mode                [RFC5086]
       0x0016  TDMoIP AAL1 Mode                  [RFC5087]
       0x0017  CESoPSN TDM with CAS              [RFC5086]
       0x0018  TDMoIP AAL2 Mode                  [RFC5087]
       0x0019  Frame Relay DLCI                  [RFC4619]
       0x001A  ROHC Transport Header-compressed  [RFC5795][RFC4901]
               Packets
       0x001B  ECRTP Transport Header-compressed [RFC3545][RFC4901]
               Packets
       0x001C  IPHC Transport Header-compressed  [RFC2507][RFC4901]
               Packets
       0x001D  cRTP Transport Header-compressed  [RFC2508][RFC4901]
               Packets
       0x001E  ATM VP Virtual Trunk
       0x001F  FC Port Mode                      [RFC6307]
       0x7FFF  Wildcard                          [RFC4863]

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Acknowledgements

   During the discussions of this work, helpful comments, suggestions,
   and reviews were received from: Sergio Belotti, Italo Busi, Miguel
   Cros Cecilia, Joe Clarke, Dhruv Dhody, Adrian Farrel, Roque Gagliano,
   Christian Jacquenet, Kireeti Kompella, Julian Lucek, Moti
   Morgenstern, Erez Segev, and Tom Petch.  Many thanks to them.

   Luay Jalil, Jichun Ma, Daniel King, and Zhang Guiyu contributed to an
   early version of this document.

   Thanks to Yingzhen Qu for the rtgdir review, Ladislav Lhotka for the
   yangdoctors review, and Chris Lonvick for the secdir review.A YANG
   module for Ethernet segments was first defined in the context of the
   EVPN device module [I-D.ietf-bess-evpn-yang].

   This work is partially supported by the European Commission under
   Horizon 2020 grant agreement number 101015857 Secured autonomic
   traffic management for a Tera of SDN flows (Teraflow).

Contributors

   Victor Lopez
   Nokia
   Email: victor.lopez@nokia.com

   Qin Wu
   Huawei
   Email: bill.wu@huawei.com

   Raul Arco
   Nokia
   Email: raul.arco@nokia.com

Authors' Addresses

   Samier Barguil
   Telefonica
   Madrid
   Spain

   Email: samier.barguilgiraldo.ext@telefonica.com

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   Oscar Gonzalez de Dios (editor)
   Telefonica
   Madrid
   Spain

   Email: oscar.gonzalezdedios@telefonica.com

   Mohamed Boucadair (editor)
   Orange
   Rennes
   France

   Email: mohamed.boucadair@orange.com

   Luis Angel Munoz
   Vodafone
   Spain

   Email: luis-angel.munoz@vodafone.com

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