Skip to main content

A YANG Data Model for Routing in Fat Trees (RIFT)
draft-ietf-rift-yang-02

The information below is for an old version of the document.
Document Type
This is an older version of an Internet-Draft whose latest revision state is "Active".
Authors Bruno Rijsman , Zheng Zhang , Yuehua Wei , Shaowen Ma , Xufeng Liu
Last updated 2021-02-22
RFC stream Internet Engineering Task Force (IETF)
Formats
Reviews
Additional resources Mailing list discussion
Stream WG state WG Document
Associated WG milestone
Aug 2020
Submit YANG module to IESG for publication
Document shepherd (None)
IESG IESG state I-D Exists
Consensus boilerplate Unknown
Telechat date (None)
Responsible AD (None)
Send notices to (None)
draft-ietf-rift-yang-02
RIFT WG                                                       B. Rijsman
Internet-Draft                                                Individual
Intended status: Standards Track                           Z. Zhang, Ed.
Expires: August 26, 2021                                          Y. Wei
                                                         ZTE Corporation
                                                                   S. Ma
                                                                  Google
                                                                  X. Liu
                                                          Volta Networks
                                                       February 22, 2021

           A YANG Data Model for Routing in Fat Trees (RIFT)
                        draft-ietf-rift-yang-02

Abstract

   This document defines a YANG data model for the configuration and
   management of Routing in Fat Trees (RIFT) Protocol.

Status of This Memo

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

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on August 26, 2021.

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 and restrictions with respect
   to this document.  Code Components extracted from this document must

Rijsman, et al.          Expires August 26, 2021                [Page 1]
Internet-Draft               RIFT YANG Model               February 2021

   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   2
     1.2.  Conventions Used in This Document . . . . . . . . . . . .   3
     1.3.  Tree Diagrams . . . . . . . . . . . . . . . . . . . . . .   3
     1.4.  Prefixes in Data Node Names . . . . . . . . . . . . . . .   3
   2.  Design of the Data Model  . . . . . . . . . . . . . . . . . .   4
     2.1.  Scope of Model  . . . . . . . . . . . . . . . . . . . . .   4
     2.2.  Specification . . . . . . . . . . . . . . . . . . . . . .   4
     2.3.  Overview  . . . . . . . . . . . . . . . . . . . . . . . .   5
     2.4.  RIFT configuration  . . . . . . . . . . . . . . . . . . .   9
     2.5.  RIFT State  . . . . . . . . . . . . . . . . . . . . . . .   9
     2.6.  Notifications . . . . . . . . . . . . . . . . . . . . . .  10
   3.  RIFT YANG model . . . . . . . . . . . . . . . . . . . . . . .  10
   4.  Security Considerations . . . . . . . . . . . . . . . . . . .  30
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  31
   6.  Acknowledgement . . . . . . . . . . . . . . . . . . . . . . .  31
   7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  32
     7.1.  Normative References  . . . . . . . . . . . . . . . . . .  32
     7.2.  Informative References  . . . . . . . . . . . . . . . . .  34
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  34

1.  Introduction

   [I-D.ietf-rift-rift] introduces the protocol definition of RIFT.
   This document defines a YANG data model that can be used to configure
   and manage the RIFT protocol.  The model is based on YANG 1.1 as
   defined in [RFC7950] and conforms to the Network Management Datastore
   Architecture (NDMA) as described in [RFC8342]

1.1.  Terminology

   The terminology for describing YANG data models is found in [RFC6020]
   and [RFC7950], including:

   o  augment

   o  container

   o  choice

   o  data model

Rijsman, et al.          Expires August 26, 2021                [Page 2]
Internet-Draft               RIFT YANG Model               February 2021

   o  data node

   o  grouping

   o  identity

   o  leaf

   o  leaf-list

   o  list

   o  module

   o  uses

   The following abbreviations are used in this document and the defined
   model:

   RIFT: Routing in Fat Trees [I-D.ietf-rift-rift].

1.2.  Conventions Used in This Document

   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.

1.3.  Tree Diagrams

   Tree diagrams used in this document follow the notation defined in
   [RFC8340].

1.4.  Prefixes in Data Node Names

   In this document, names of data nodes, actions, and other data model
   objects are often used without a prefix, as long as it is clear from
   the context in which YANG module each name is defined.  Otherwise,
   names are prefixed using the standard prefix associated with the
   corresponding YANG module, as shown in Table 1.

Rijsman, et al.          Expires August 26, 2021                [Page 3]
Internet-Draft               RIFT YANG Model               February 2021

            +---------------+--------------------+-----------+
            | Prefix        | YANG module        | Reference |
            +---------------+--------------------+-----------+
            | yang          | ietf-yang-types    | [RFC6991] |
            |               |                    |           |
            | inet          | ietf-inet-types    | [RFC6991] |
            |               |                    |           |
            | rt            | ietf-routing       | [RFC8349] |
            |               |                    |           |
            | if            | ietf-interfaces    | [RFC8343] |
            |               |                    |           |
            | rt-types      | ietf-routing-types | [RFC8294] |
            |               |                    |           |
            | iana-rt-types | iana-routing-types | [RFC8294] |
            +---------------+--------------------+-----------+

                                  Table 1

2.  Design of the Data Model

2.1.  Scope of Model

   The model covers RIFT [I-D.ietf-rift-rift].

   This model can be used to configure and manage the RIFT protocol.
   The operational state data and statistics can be retrieved by this
   model.  The subscription and push mechanism defined in [RFC8639] and
   [RFC8641] can be implemented by the user to subscribe to
   notifications on the data nodes in this model.

   The model contains all the basic configuration parameters to operate
   the protocol.  Depending on the implementation choices, some systems
   may not allow some of the advanced parameters to be configurable.
   The occasionally implemented parameters are modeled as optional
   features in this model.  This model can be extended, and it has been
   structured in a way that such extensions can be conveniently made.

   The RIFT YANG module augments the /routing/control-plane-protocols/
   control-plane-protocol path defined in the ietf-routing module.  The
   ietf-rift model defines a single instance of RIFT.  Multiple
   instances are instantiated as multiple control-plane protocols
   instances.

2.2.  Specification

   This model imports and augments ietf-routing YANG model defined in
   [RFC8349].  Both configuration branch and state branch of [RFC8349]
   are augmented.  The configuration branch covers node base and policy

Rijsman, et al.          Expires August 26, 2021                [Page 4]
Internet-Draft               RIFT YANG Model               February 2021

   configuration.  The container "rift" is the top level container in
   this data model.  The presence of this container is expected to
   enable RIFT protocol functionality.

   The YANG data model defined in this document conforms to the Network
   Management Datastore Architecture (NMDA) [RFC8342].  The operational
   state data is combined with the associated configuration data in the
   same hierarchy [RFC8407].

2.3.  Overview

   The RIFT YANG module defined in this document has all the common
   building blocks for the RIFT protocol.

   The RIFT YANG module augments the /routing/control-plane-protocols/
   control-plane-protocol path defined in the ietf-routing module.  The
   ietf-rift model defines a single instance of RIFT.  Multiple
   instances are instantiated as multiple control-plane protocols
   instances.

   module: ietf-rift
     augment /rt:routing/rt:control-plane-protocols
               /rt:control-plane-protocol:
       +--rw rift
          +--rw name?                        string
          +--ro level?                       level
          +--rw system-id                    system-id
          +--rw pod?                         uint32
          +--rw configured-level?            level
          +--rw overload?                    boolean
          +--ro protocol-major-version       uint8
          +--ro protocol-minor-version       uint16
          +--ro hierarchy-indications?       enumeration
          +--rw flood-reduction?             boolean
          +--rw nonce-increasing-interval?   uint16
          +--rw maximum-nonce-delta?         uint8 {nonce-delta-adjust}?
          +--rw rx-lie-multicast-address
          |  +--rw ipv4?   inet:ipv4-address
          |  +--rw ipv6?   inet:ipv6-address
          +--rw tx-lie-multicast-address
          |  +--rw ipv4?   inet:ipv4-address
          |  +--rw ipv6?   inet:ipv6-address
          +--rw lie-tx-port?                 inet:port-number
          +--rw global-link-capabilities
          |  +--rw bfd?                     boolean
          |  +--rw v4-forwarding-capable?   boolean
          +--rw rx-flood-port?               inet:port-number
          +--rw holdtime?

Rijsman, et al.          Expires August 26, 2021                [Page 5]
Internet-Draft               RIFT YANG Model               February 2021

          |       rt-types:timer-value-seconds16
          +--rw tide-generation-interval?
          |       rt-types:timer-value-seconds16
          +--rw tie-security-key-id?         uint32
          +--rw interface* [name]
          |  +--ro link-id?                       linkid-type
          |  +--rw name                           if:interface-ref
          |  +--rw cost?                          uint32
          |  +--rw address-families
          |  |  +--rw address-family* [address-family]
          |  |     +--rw address-family    iana-rt-types:address-family
          |  +--rw advertised-source-addresses
          |  |  +--rw ipv4?   inet:ipv4-address
          |  |  +--rw ipv6?   inet:ipv6-address
          |  +--ro direction-type?                enumeration
          |  +--ro was-the-last-lie-accepted?     boolean
          |  +--ro last-lie-reject-reason?        string
          |  +--ro advertised-in-lies
          |  |  +--ro you-are-flood-repeater?        boolean
          |  |  +--ro not-a-ztp-offer?               boolean
          |  |  +--ro you-are-sending-too-quickly?   boolean
          |  +--rw link-capabilities
          |  |  +--rw bfd?                     boolean
          |  |  +--rw v4-forwarding-capable?   boolean
          |  +--ro state                          enumeration
          |  +--ro number-of-flaps?               uint32
          |  +--ro last-state-change?             yang:date-and-time
          +--ro miscabled-links*             linkid-type
          +--rw (algorithm-type)?
          |  +--:(spf)
          |  +--:(all-path)
          +--ro hal?                         level
          +--rw instance-label?              uint32 {label-switching}?
          +--ro neighbor* [system-id]
          |  +--ro name?                         string
          |  +--ro level?                        level
          |  +--ro system-id                     system-id
          |  +--ro pod?                          uint32
          |  +--ro protocol-version?             uint16
          |  +--ro protocol-minor-version?       uint16
          |  +--ro sent-offer
          |  |  +--ro level?             level
          |  |  +--ro not-a-ztp-offer?   boolean
          |  +--ro received-offer
          |  |  +--ro level?                        level
          |  |  +--ro not-a-ztp-offer?              boolean
          |  |  +--ro best?                         boolean
          |  |  +--ro removed-from-consideration?   boolean

Rijsman, et al.          Expires August 26, 2021                [Page 6]
Internet-Draft               RIFT YANG Model               February 2021

          |  |  +--ro removal-reason?               string
          |  +--ro received-source-addresses
          |  |  +--ro ipv4?   inet:ipv4-address
          |  |  +--ro ipv6?   inet:ipv6-address
          |  +--ro link-id-pair* [remote-id]
          |  |  +--ro local-id?    uint32
          |  |  +--ro remote-id    uint32
          |  |  +--ro if-index?    uint32
          |  |  +--ro if-name?     if:interface-ref
          |  +--ro cost?                         uint32
          |  +--ro bandwidth?                    uint32
          |  +--ro flood-reduction?              boolean
          |  +--ro received-link-capabilities
          |  |  +--ro bfd?                     boolean
          |  |  +--ro v4-forwarding-capable?   boolean
          |  +--ro received-in-lies
          |  |  +--ro you-are-flood-repeater?        boolean
          |  |  +--ro not-a-ztp-offer?               boolean
          |  |  +--ro you-are-sending-too-quickly?   boolean
          |  +--ro tx-flood-port?                inet:port-number
          |  +--ro bfd-up?                       boolean
          |  +--ro outer-security-key-id?        uint8
          +--ro database
             +--ro tie* [direction-type originator tie-type tie-number]
                +--ro direction-type          enumeration
                +--ro originator              system-id
                +--ro tie-type                enumeration
                +--ro tie-number              uint32
                +--ro seq?                    uint64
                +--ro origination-time?       uint32
                +--ro origination-lifetime?   uint32
                +--ro node
                |  +--ro name?              string
                |  +--ro level?             level
                |  +--ro system-id          system-id
                |  +--ro pod?               uint32
                |  +--ro flood-reduction?   boolean
                |  +--ro overload?          boolean
                |  +--ro startup-time?      uint64
                |  +--ro neighbor* [system-id]
                |  |  +--ro name?                         string
                |  |  +--ro level?                        level
                |  |  +--ro system-id                     system-id
                |  |  +--ro pod?                          uint32
                |  |  +--ro link-id-pair* [remote-id]
                |  |  |  +--ro local-id?    uint32
                |  |  |  +--ro remote-id    uint32
                |  |  |  +--ro if-index?    uint32

Rijsman, et al.          Expires August 26, 2021                [Page 7]
Internet-Draft               RIFT YANG Model               February 2021

                |  |  |  +--ro if-name?     if:interface-ref
                |  |  +--ro cost?                         uint32
                |  |  +--ro bandwidth?                    uint32
                |  |  +--ro flood-reduction?              boolean
                |  |  +--ro received-link-capabilities
                |  |     +--ro bfd?                     boolean
                |  |     +--ro v4-forwarding-capable?   boolean
                |  +--ro miscabled-links*   linkid-type
                +--ro prefix
                |  +--ro prefix?              inet:ip-prefix
                |  +--ro (type)?
                |  |  +--:(prefix)
                |  |  +--:(positive-disaggregation)
                |  |  +--:(negative-disaggregation)
                |  |  +--:(external)
                |  |  +--:(positive-external-disaggregation)
                |  |  +--:(pgp)
                |  +--ro metric?              uint32
                |  +--ro tags*                uint64
                |  +--ro monotonic-clock
                |  |  +--ro prefix-sequence-type
                |  |     +--ro timestamp
                |  |     |       ieee802-1as-timestamp-type
                |  |     +--ro transaction-id?   uint8
                |  +--ro loopback?            boolean
                |  +--ro directly-attached?   boolean
                |  +--ro from-link?           linkid-type
                +--ro key-value
                   +--ro key?     binary
                   +--ro value?   binary

     notifications:
       +---n error-set
          +--ro tie-level-error
          |  +--ro tie* [originator]
          |     +--ro direction-type?         enumeration
          |     +--ro originator              system-id
          |     +--ro tie-type?               enumeration
          |     +--ro tie-number?             uint32
          |     +--ro seq?                    uint64
          |     +--ro origination-time?       uint32
          |     +--ro origination-lifetime?   uint32
          +--ro neighbor-error
             +--ro neighbor* [system-id]
                +--ro name?                         string
                +--ro level?                        level
                +--ro system-id                     system-id
                +--ro pod?                          uint32

Rijsman, et al.          Expires August 26, 2021                [Page 8]
Internet-Draft               RIFT YANG Model               February 2021

                +--ro protocol-version?             uint16
                +--ro protocol-minor-version?       uint16
                +--ro sent-offer
                |  +--ro level?             level
                |  +--ro not-a-ztp-offer?   boolean
                +--ro received-offer
                |  +--ro level?                        level
                |  +--ro not-a-ztp-offer?              boolean
                |  +--ro best?                         boolean
                |  +--ro removed-from-consideration?   boolean
                |  +--ro removal-reason?               string
                +--ro received-source-addresses
                |  +--ro ipv4?   inet:ipv4-address
                |  +--ro ipv6?   inet:ipv6-address
                +--ro link-id-pair* [remote-id]
                |  +--ro local-id?    uint32
                |  +--ro remote-id    uint32
                |  +--ro if-index?    uint32
                |  +--ro if-name?     if:interface-ref
                +--ro cost?                         uint32
                +--ro bandwidth?                    uint32
                +--ro flood-reduction?              boolean
                +--ro received-link-capabilities
                |  +--ro bfd?                     boolean
                |  +--ro v4-forwarding-capable?   boolean
                +--ro received-in-lies
                |  +--ro you-are-flood-repeater?        boolean
                |  +--ro not-a-ztp-offer?               boolean
                |  +--ro you-are-sending-too-quickly?   boolean
                +--ro tx-flood-port?                inet:port-number
                +--ro bfd-up?                       boolean
                +--ro outer-security-key-id?        uint8

2.4.  RIFT configuration

   The configuration data nodes cover node configuration attributes.
   RIFT configurations require node base information configurations.
   Some features can be used to enhance protocol, such as BFD, flooding-
   reducing, community attribute.

2.5.  RIFT State

   The state data nodes include node, neighbor, database and kv-store
   information.

Rijsman, et al.          Expires August 26, 2021                [Page 9]
Internet-Draft               RIFT YANG Model               February 2021

2.6.  Notifications

   Unexpected TIE and neighbor's layer error should be notified.

3.  RIFT YANG model

   This module references [I-D.ietf-rift-rift], [RFC5881], [RFC6991],
   [RFC8177], [RFC8294], [RFC8343], [RFC8349], [RFC8505].

 <CODE BEGINS> file "ietf-rift@2021-02-20.yang"
 module ietf-rift {

   yang-version 1.1;

   namespace "urn:ietf:params:xml:ns:yang:ietf-rift";
   prefix rift;

   import ietf-inet-types {
     prefix "inet";
     reference "RFC 6991: Common YANG Data Types";
   }

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

   import ietf-routing {
     prefix "rt";
     reference
       "RFC 8349: A YANG Data Model for Routing Management
        (NMDA Version)";
   }

   import ietf-interfaces {
     prefix "if";
     reference
       "RFC 8343: A YANG Data Model for Interface Management";
   }

   import ietf-routing-types {
     prefix "rt-types";
     reference
       "RFC 8294: Common YANG Data Types for the Routing Area";
   }

   import iana-routing-types {
     prefix "iana-rt-types";

Rijsman, et al.          Expires August 26, 2021               [Page 10]
Internet-Draft               RIFT YANG Model               February 2021

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

   organization
     "IETF RIFT (Routing In Fat Trees) Working Group";

   contact
     "WG Web:   <http://tools.ietf.org/wg/rift/>
      WG List:  <mailto:rift@ietf.org>

      Editor:   Zheng Zhang
                <mailto:zhang.zheng@zte.com.cn>

      Editor:   Yuehua Wei
                <mailto:wei.yuehua@zte.com.cn>

      Editor:   Shaowen Ma
                <mailto:mashaowen@gmail.com>

      Editor:   Xufeng Liu
                <mailto:xufeng.liu.ietf@gmail.com>";

   // RFC Ed.: replace XXXX with actual RFC number and remove
   // this note

   description
     "The module defines the YANG definitions for Routing in Fat
      Trees (RIFT).

      Copyright (c) 2020 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
      (https://trustee.ietf.org/license-info).

      This version of this YANG module is part of RFC XXXX
      (https://www.rfc-editor.org/info/rfcXXXX); see the RFC
      itself for full legal notices.

      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 (RFC 2119)

Rijsman, et al.          Expires August 26, 2021               [Page 11]
Internet-Draft               RIFT YANG Model               February 2021

      (RFC 8174) when, and only when, they appear in all
      capitals, as shown here.";

   revision 2021-02-20 {
     description "Initial revision.";
     reference "RFC XXXX: A YANG Data Model for RIFT.";
   }

   /*
    * Features
    */

   feature nonce-delta-adjust {
     description
       "Support weak nonce delta adjusting which is used in security
        in section 4.4.";
   }

   feature label-switching {
     description
       "Support label switching for instance distinguishing in
        section 4.3.7.";
   }

   typedef system-id {
     type string {
       pattern
       '[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}\.[0-9A-Fa-f]{4}';
     }
     description
       "This type defines RIFT system id using pattern,
        the system id looks like: 0143.0438.0100.AeF0";
   }

   typedef level {
     type uint8 {
       range "0 .. 24";
     }
     default "0";
     description "The value of node level. The max value is 24.";
   }

   typedef linkid-type {
     type uint32;
     description "This type defines the link id of an interface.";
   }

   typedef ieee802-1as-timestamp-type {

Rijsman, et al.          Expires August 26, 2021               [Page 12]
Internet-Draft               RIFT YANG Model               February 2021

     type uint64;
     description
       "Timestamp per 802.1AS. It is advertised with prefix to
        achieve mobility as described in section 4.3.3.";
   }

   /*
    * Identity
    */
   identity rift {
     base rt:routing-protocol;
     description "Identity for the RIFT routing protocol.";
   }

   /*
    * Groupings
    */

    grouping base-node-info {
     leaf name {
       type string;
       description
         "The name of this node. It won't be used as the key of node,
          just used for description.";
     }
     leaf level {
       type level;
       config false;
       description "The level of this node.";
     }
     leaf system-id {
       type system-id;
       mandatory true;
       description
         "Each node is identified via a system-id which is 64 bits
          wide.";
     }
     leaf pod {
       type uint32;
       description
         "Point of Delivery. The self-contained vertical slice of a
          Clos or Fat Tree network containing normally only level 0
          and level 1 nodes. It communicates with nodes in other PoDs
          via the spine. We number PoDs to distinguish them and use
          PoD #0 to denote 'undefined' PoD.";
     }
     description "The base information of a node.";
   } // base-node-info

Rijsman, et al.          Expires August 26, 2021               [Page 13]
Internet-Draft               RIFT YANG Model               February 2021

   grouping node-flag {
     leaf overload {
       type boolean;
       description "If the overload bit in TIEs can be set.";
     }
     description "The node flag information.";
   }

   grouping link-capabilities {
     leaf bfd {
       type boolean;
       description
         "If this value is set to true, it means that
          BFD [RFC5881] function is enabled on the neighbor.";
     }
     leaf v4-forwarding-capable {
       type boolean;
       description
         "If this value is set to true, it means that
          the neighbor supports v4 forwarding.";
     }
     description "The features of neighbor.";
   } // link-capabilities

   grouping addresses {
     leaf ipv4 {
       type inet:ipv4-address;
       description "IPv4 address to be used.";
     }
     leaf ipv6 {
       type inet:ipv6-address;
       description "IPv6 address to be used.";
     }
     description "IPv4 or IPv6 address to be used.";
   }

   grouping lie-elements{
     leaf you-are-flood-repeater {
       type boolean;
       description
         "If the neighbor on this link is flooding repeater
          described in section 4.2.3.9. When this value is set
          to true, the value can be carried in exchanged
          packet.";
     }
     leaf not-a-ztp-offer {
       type boolean;
       description

Rijsman, et al.          Expires August 26, 2021               [Page 14]
Internet-Draft               RIFT YANG Model               February 2021

         "As described in section 4.2.7. When this value is
          set to true, the flag can be carried in the LIE
          packet. When the value received in the LIE from
          neighbor, it indicates the level on the LIE MUST
          NOT be used to derive a ZTP level by the receiving
          node.";
     }
     leaf you-are-sending-too-quickly {
       type boolean;
       description
         "Can be optionally set to indicate to neighbor that
          packet losses are seen on reception based on packet
          numbers or the rate is too high. The receiver SHOULD
          temporarily slow down flooding rates. When this value
          is set to true, the flag can be carried in packet.";
     }
     description "The elements set in the LIEs.";
   } // lie-elements

   grouping link-id-pair {
     leaf local-id {
       type uint32;
       description "The local-id of link connect to this neighbor.";
     }
     leaf remote-id {
       type uint32;
       description "The remote-id to reach this neighbor.";
     }
     leaf if-index {
       type uint32;
       description "The local index of this interface.";
     }
     leaf if-name {
       type if:interface-ref;
       description "The name of this interface.";
     }
     description
       "A pair of local and remote link IDs to identify a link between
        two nodes.";
   } // link-id-pair

   grouping neighbor-node {
     list link-id-pair {
       key "remote-id";
       uses link-id-pair;
       description
         "The Multiple parallel links to this neighbor.";
     }

Rijsman, et al.          Expires August 26, 2021               [Page 15]
Internet-Draft               RIFT YANG Model               February 2021

     leaf cost {
       type uint32;
       description "The cost value advertised by the neighbor.";
     }
     leaf bandwidth {
       type uint32;
       description
         "Total bits bandwith to neighbor, this will be
          normally sum of the bandwidths of all the
          parallel links.";
     }
     leaf flood-reduction {
       type boolean;
       description
         "If this neighbor enables the flood reduction function.";
     }
     container received-link-capabilities {
       uses link-capabilities;
       description
         "The link capabilities advertised by the neighbor.";
     }
     description "The neighbor information indicated in node TIE.";
   } // neighbor-node

   grouping neighbor {
     leaf protocol-version {
       type uint16;
       description
         "Represents the protocol encoding schema version of
          this neighbor.";
     }
     leaf protocol-minor-version {
       type uint16;
       description
         "Represents the minor protocol encoding schema
          version of this neighbor.";
     }
     container sent-offer {
       leaf level {
         type level;
         description "The level value.";
       }
       leaf not-a-ztp-offer {
         type boolean;
         description "If the neighbor needs to be offer a level.";
       }
       description
         "The level sent to the neighbor in case the neighbor

Rijsman, et al.          Expires August 26, 2021               [Page 16]
Internet-Draft               RIFT YANG Model               February 2021

          needs to be offered.";
     }
     container received-offer {
       leaf level {
         type level;
         description "The level value.";
       }
       leaf not-a-ztp-offer {
         type boolean;
         description
           "If this interface needs to be offered a level.";
       }
       leaf best {
         type boolean;
         description
           "If level is the best level received from all
            the neighbors.";
       }
       leaf removed-from-consideration {
         type boolean;
         description
           "If the level value is considered to be used.
            If the value is not considered to be used,
            this value is set to 'TRUE'.";
       }
       leaf removal-reason {
         type string;
         description
           "The reason why this value is not considered to
            be used.";
       }
       description
         "The level offered to the interface from the neighbor.
          And if the level value is considered to be used.";
     }
     container received-source-addresses {
       uses addresses;
       description
         "The source address of LIE and TIE packets from
          the neighbor.";
     } // received-offer
     uses neighbor-node;
     container received-in-lies {
       uses lie-elements;
       description "The attributes received from this neighbor.";
     }
     leaf tx-flood-port {
       type inet:port-number;

Rijsman, et al.          Expires August 26, 2021               [Page 17]
Internet-Draft               RIFT YANG Model               February 2021

       default "915";
       description
         "The UDP port which is used by the neighbor to flood TIEs.";
     }
     leaf bfd-up {
       type boolean;
       description
         "Indication whether the link is protected by established
          BFD session.";
     }
     leaf outer-security-key-id {
       type uint8;
       description
         "As described in section 4.4.3, the received security
          key id from the neighbor.";
     }
     description "The neighbor information.";
   } // neighbor

   grouping direction-type {
     leaf direction-type {
       type enumeration {
         enum illegal {
           description "Illegal direction.";
         }
         enum south {
           description "A link to a node one level down.";
         }
         enum north {
           description "A link to a node one level up.";
         }
         enum east-west {
           description "A link to a node in the same level.";
         }
         enum max {
           description "The max value of direction.";
         }
       }
       config false;
       description "The type of a link.";
     }
     description "The type of a link.";
   } // direction-type

   grouping tie-header {
     uses direction-type;
     leaf originator {
       type system-id;

Rijsman, et al.          Expires August 26, 2021               [Page 18]
Internet-Draft               RIFT YANG Model               February 2021

       description "The originator's system-id of this TIE.";
     }

     leaf tie-type {
       type enumeration {
         enum "node" {
           description "The node TIE.";
         }
         enum "prefix" {
           description "The prefix TIE.";
         }
         enum "positive-disaggregation-prefix" {
           description "The positive disaggregation prefix TIE.";
         }
         enum "negative-disaggregation-prefix" {
           description "The negative disaggregation prefix TIE.";
         }
         enum "pgp-prefix" {
           description "The policy guide prefix TIE.";
         }
         enum "key-value" {
           description "The key value TIE.";
         }
         enum "external-prefix" {
           description "The external prefix TIE.";
         }
         enum "positive-external-disaggregation-prefix" {
           description
             "The positive external disaggregation prefix TIE.";
         }
       }
       description "The types of TIE.";
     }

     leaf tie-number {
       type uint32;
       description "The number of this TIE";
     }

     leaf seq {
       type uint64;
       description
         "As described in section 4.2.3.1, the sequence number
          of a TIE.";
     }
     leaf origination-time {
       type uint32;
       description

Rijsman, et al.          Expires August 26, 2021               [Page 19]
Internet-Draft               RIFT YANG Model               February 2021

         "Absolute timestamp when the TIE was generated. This can
         be used on fabrics with synchronized clock to prevent
         lifetime modification attacks.";
     }
     leaf origination-lifetime {
       type uint32;
       description
         "Original lifetime when the TIE was generated.
          This can be used on fabrics with synchronized clock to
          prevent lifetime modification attacks.";
     }

     description
       "TIE is the acronym for 'Topology Information Element'.
        TIEs are exchanged between RIFT nodes to describe parts
        of a network such as links and address prefixes.
        This is the TIE header information.";
   } // tie-header

   /*
    * Data nodes
    */
   augment "/rt:routing/rt:control-plane-protocols"
            + "/rt:control-plane-protocol" {
     when "derived-from-or-self(rt:type, 'rift:rift')" {
       description
         "This augment is only valid when routing protocol
          instance type is 'RIFT'.";
     }
     description "RIFT ( Routing in Fat Trees ) YANG model.";

     container rift {
       description "RIFT configuration and state data.";

       uses base-node-info;
       leaf configured-level {
         type level;
         description
           "The configured level value of this node.";
       }
       uses node-flag;

       leaf protocol-major-version {
         type uint8;
         config false;
         mandatory true;
         description
           "Represents protocol encoding schema major version.";

Rijsman, et al.          Expires August 26, 2021               [Page 20]
Internet-Draft               RIFT YANG Model               February 2021

       }
       leaf protocol-minor-version {
         type uint16;
         config false;
         mandatory true;
         description
           "Represents protocol encoding schema minor version.";
       }
       leaf hierarchy-indications {
         type enumeration {
           enum "leaf-only" {
             description
               "The node will never leave the
                'bottom of the hierarchy'.";
           }
           enum "leaf-only-and-leaf-2-leaf-procedures" {
             description "This means leaf to leaf.";
           }
           enum "top-of-fabric" {
             description "The node is 'top of fabric'.";
           }
         }
         config false;
         description "The hierarchy indications of this node.";
       }

       leaf flood-reduction {
         type boolean;
         description
           "If the node supports flood reduction function defined in
            section 4.2.3.8. If this value is set to 'FALSE', it
            means that the flood reduction function is disabled.";
       }

       leaf nonce-increasing-interval {
         type uint16;
         units seconds;
         description
           "The configurable nonce increasing interval.";
       }
       leaf maximum-nonce-delta {
         if-feature nonce-delta-adjust;
         type uint8 {
           range "1..5";
         }
         description
           "The configurable valid nonce delta value used for
            security. It is used as vulnerability window defined

Rijsman, et al.          Expires August 26, 2021               [Page 21]
Internet-Draft               RIFT YANG Model               February 2021

            in section 4.4.7.
            If the nonces in received packet exceeds the range
            indicated by this value, the packet MUST be discarded.";
       }
       container rx-lie-multicast-address {
         uses addresses;
         description
           "The configurable LIE receiving IPv4/IPv6 multicast
            address. '224.0.0.120' is default address value.
            Different multicast addresses can be used for receiving
            and sending.";
       }
       container tx-lie-multicast-address {
         uses addresses;
         description
           "The configurable LIE sending IPv4/IPv6 multicast
            address. 'FF02::A1F7' is default address value.
            Different multicast addresses can be used for receiving
            and sending.";
       }
       leaf lie-tx-port {
         type inet:port-number;
         description
           "The UDP port of LIE packet sending. The default port
            number is 914. The value can be set to other value
            associated with different RIFT instance.";
       }

       container global-link-capabilities {
         uses link-capabilities;
         description
           "The node default link capabilities. It can be overwrite
            by the configuration underneath interface and neighbor.";
       }

       leaf rx-flood-port {
         type inet:port-number;
         default "915";
         description
           "The UDP port which can be used to receive flooded
            TIEs. The default port number is 915. The value can
            be set to other value associated with different
            RIFT instance.";
       }
       leaf holdtime {
         type rt-types:timer-value-seconds16;
         units seconds;
         default "3";

Rijsman, et al.          Expires August 26, 2021               [Page 22]
Internet-Draft               RIFT YANG Model               February 2021

         description "The holding time of LIE.";
       }
       leaf tide-generation-interval {
         type rt-types:timer-value-seconds16;
         units seconds;
         default "5";
         description "The TIDE generation interval.";
       }

       leaf tie-security-key-id {
         type uint32;
         description
           "As described in section 4.4.3, this value implies key
            type and algorithm.  Value 0 means that no valid
            fingerprint was computed. This key ID scope is local
            to the nodes on both ends of the adjacency.";
       }

       list interface {
         key "name";
         leaf link-id {
           type linkid-type;
           config false;
           description "The local id of this interface.";
         }
         leaf name {
           type if:interface-ref;
           description "The interface's name.";
         }
         leaf cost {
           type uint32;
           description
             "The cost from this interface to the neighbor.";
         }
         container address-families {
           description
             "Containing address families on the interface.";
           list address-family {
             key address-family;
             description
               "A list of address families enabled on the
                interface.";
             leaf address-family {
               type iana-rt-types:address-family;
               description
                 "Indication which address families are up on the
                  interface.";
             }

Rijsman, et al.          Expires August 26, 2021               [Page 23]
Internet-Draft               RIFT YANG Model               February 2021

           }
         }
         container advertised-source-addresses {
           uses addresses;
           description
             "The address used in the advertised LIE and TIE
              packets.";
         }
         uses direction-type;

         leaf was-the-last-lie-accepted {
           type boolean;
           config false;
           description
             "If the most recently received LIE was accepted or
              rejected. If the LIE was rejected, the neighbor error
              notifications should be used to find the reason.";
         }
         leaf last-lie-reject-reason {
           type string;
           config false;
           description
             "Description for the reject reason of the last LIE.";
         }
         container advertised-in-lies {
           config false;
           uses lie-elements;
           description
             "The attributes advertised in the LIEs from
              this interface.";
         }
         container link-capabilities {
           uses link-capabilities;
           description
             "The interface's link capabilities.";
         }
         leaf state {
           type enumeration {
             enum "OneWay" {
               description "The initial state of neighbor.";
             }
             enum "TwoWay" {
               description "This means leaf to leaf.";
             }
             enum "ThreeWay" {
               description "The node is 'top of fabric'.";
             }
             enum "Multiple-Neighbors-Wait" {

Rijsman, et al.          Expires August 26, 2021               [Page 24]
Internet-Draft               RIFT YANG Model               February 2021

               description "The node is 'top of fabric'.";
             }
           }
           config false;
           mandatory true;
           description "The hierarchy indications of this node.";
         }
         leaf number-of-flaps {
           type uint32;
           config false;
           description
             "The number of interface state flaps.";
         }
         leaf last-state-change {
           type yang:date-and-time;
           config false;
           description "Time duration in the current state.";
         }

         description "The interface information on this node.";
       } // list interface

       leaf-list miscabled-links {
         type linkid-type;
         config false;
         description "List of miscabled links.";
       }

       choice algorithm-type {
         case spf {
           description "The algorithm is SPF.";
         }
         case all-path {
           description "The algorithm is all-path.";
         }
         description "The possible algorithm types.";
       }

       leaf hal {
         type level;
         config false;
         description
           "The highest defined level value seen from all valid
            level offers received.";
       }

       leaf instance-label {
         if-feature label-switching;

Rijsman, et al.          Expires August 26, 2021               [Page 25]
Internet-Draft               RIFT YANG Model               February 2021

         type uint32;
         description
           "As per section 4.3.7, a locally significant, downstream
            assigned, interface specific label may be advertised in
            its LIEs. This value can be used to distinguish among
            multiple RIFT instances.";
       }

       list neighbor {
         key "system-id";
         config false;
         uses base-node-info;
         uses neighbor;
         description "The neighbor's information.";
       }

       container database {
         config false;
         list tie {
           key "direction-type originator tie-type tie-number";
           description
             "A list of TIEs (Topology Information Elements).";
           uses tie-header;

           container node {
             uses base-node-info;
             leaf flood-reduction {
               type boolean;
               description
                 "If the node enable the flood reduction function.";
             }
             uses node-flag;
             leaf startup-time {
               type uint64;
               description "Startup time of the node.";
             }
             list neighbor {
               key "system-id";
               uses base-node-info;
               uses neighbor-node;
               description "The node TIE information of a neighbor.";
             }

             leaf-list miscabled-links {
               type linkid-type;
               config false;
                 description "List of miscabled links.";
             }

Rijsman, et al.          Expires August 26, 2021               [Page 26]
Internet-Draft               RIFT YANG Model               February 2021

             description "The node element information in this TIE.";
           } // node

           container prefix {
             leaf prefix {
               type inet:ip-prefix;
               description "The prefix information.";
             }

             choice type {
               case prefix {
                 description "It is the prefixes TIE element.";
               }
               case positive-disaggregation {
                 description
                   "It is the positive disaggregation prefixes
                    TIE element.";
               }
               case negative-disaggregation {
                 description
                   "It is the negative disaggregation prefixes
                    TIE element.";
               }
               case external {
                 description
                   "It is the external prefixes TIE element.";
               }
               case positive-external-disaggregation {
                 description
                   "It is the positive external disaggregation
                    prefixes TIE element.";
               }
               case pgp {
                 description
                   "It is the policy guide prefixes TIE element.";
               }
               description "The type of prefix TIE.";
             }

             leaf metric {
               type uint32;
               description "The metric of this prefix.";
             }
             leaf-list tags {
               type uint64;
               description "The tags of this prefix.";
             }
             container monotonic-clock {

Rijsman, et al.          Expires August 26, 2021               [Page 27]
Internet-Draft               RIFT YANG Model               February 2021

               container prefix-sequence-type {
                 leaf timestamp {
                   type ieee802-1as-timestamp-type;
                   mandatory true;
                   description
                     "The timestamp per 802.1AS can be advertised
                      with the desired prefix North TIEs.";
                 }
                 leaf transaction-id {
                   type uint8;
                   description
                     "As per RFC 8505, a sequence number called a
                      Transaction ID (TID) with a prefix can be
                      advertised.";
                 }
                 description
                   "As described in section 4.3.3, the prefix
                    sequence attribute which can be advertised
                    for mobility.";
               }
               description
                 "The monotonic clock for mobile addresses.";
             }
             leaf loopback {
               type boolean;
               description
                 "Indicates if the interface is a node loopback.
                  According to section 4.3.10, the node's loopback
                  address can be injected into North and South
                  Prefix TIEs for node reachability.";
             }
             leaf directly-attached {
               type boolean;
               description
                 "Indicates that the prefix is directly attached,
                  i.e. should be routed to even if the node is
                  in overload.";
             }
             leaf from-link {
               type linkid-type;
               description
                 "In case of locally originated prefixes,
                  i.e. interface addresses this can describe which
                  link the address belongs to.";
             }
             description "The detail information of a prefix.";
           } // prefix

Rijsman, et al.          Expires August 26, 2021               [Page 28]
Internet-Draft               RIFT YANG Model               February 2021

           container key-value {
             leaf key {
               type binary;
               description "The type of key value combination.";
             }
             leaf value {
               type binary;
               description "The value of key value combination.";
             }
             description
               "The information used to distinguish a Key/Value
                pair. When the type of kv is set to 'node',
                node-element is making sense. When the type of
                kv is set to other values except 'node',
                prefix-info is making sense.";
           } // kv-store
         } // ties
         description "The TIEs information in database.";
       }// container database
     }//rift
   }//augment

   /*
    * Notifications
    */
   notification error-set {
     description "The errors notification of RIFT.";
     container tie-level-error {
       list tie {
         key "originator";
         uses tie-header;
         description "The level is undefined in the LIEs.";
       }
       description "The TIE errors set.";
     }
     container neighbor-error {
       list neighbor {
         key "system-id";
         uses base-node-info;
         uses neighbor;
         description "The information of a neighbor.";
       }
       description "The neighbor errors set.";
     }
   }
 }
 <CODE ENDS>

Rijsman, et al.          Expires August 26, 2021               [Page 29]
Internet-Draft               RIFT YANG Model               February 2021

4.  Security Considerations

   The YANG module specified in this document defines a 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 NETCONF access control model [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 this YANG module 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)
   to these data nodes without proper protection can have a negative
   effect on network operations.  Writable data node represent
   configuration of each instance, node, interface, etc.  These
   correspond to the following schema nodes:

   o  /rift

   o  /rift/node/

   Modifying the configuration may cause all the RIFT neighborship to be
   rebuilt.  For example, the configuration changing of level or
   systemid, will lead to all the neighbor connections of this node
   rebuilt.  The incorrect modification of authentication, except for
   the neighbor connection broken, will lead to the permanent connection
   broken.  The modification of interface, will lead to the neighbor
   state changing.  In general, unauthorized modification of most RIFT
   configurations will pose there own set of security risks and the
   "Security Considerations" in the respective reference RFCs should be
   consulted.

   Some of the readable data nodes in this 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:

   o  /rift

   o  /rift/interface

Rijsman, et al.          Expires August 26, 2021               [Page 30]
Internet-Draft               RIFT YANG Model               February 2021

   o  /rift/database

   o  /rift/kv-store

   The exposure of the database will expose the detailed topology of the
   network.  Network operators may consider their topologies to be
   sensitive confidential data.

   For RIFT authentication, configuration is supported via the
   specification of key-chains [RFC8177] or the direct specification of
   key and authentication algorithm.  Hence, authentication
   configuration inherits the security considerations of [RFC8177].
   This includes the considerations with respect to the local storage
   and handling of authentication keys.

5.  IANA Considerations

   RFC Ed.: Please replace all occurrences of 'XXXX' with the actual RFC
   number (and remove this note).

   This document registers a URI in the IETF XML registry [RFC3688].
   Following the format in [RFC3688], the following registration is
   requested to be made:

   URI: urn:ietf:params:xml:ns:yang:ietf-rift

   Registrant Contact: The IESG

   XML: N/A, the requested URI is an XML namespace.

   This document also requests one new YANG module name in the YANG
   Module Names registry [RFC6020] with the following suggestion:

   name: ietf-rift

   namespace: urn:ietf:params:xml:ns:yang:ietf-rift

   prefix: rift

   reference: RFC XXXX

6.  Acknowledgement

   The authors would like to thank Tony Przygienda, Benchong Xu
   (xu.benchong@zte.com.cn), for their review, valuable comments and
   suggestions.

Rijsman, et al.          Expires August 26, 2021               [Page 31]
Internet-Draft               RIFT YANG Model               February 2021

7.  References

7.1.  Normative References

   [I-D.ietf-rift-rift]
              Przygienda, T., Sharma, A., Thubert, P., Rijsman, B., and
              D. Afanasiev, "RIFT: Routing in Fat Trees", draft-ietf-
              rift-rift-12 (work in progress), May 2020.

   [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>.

   [RFC5881]  Katz, D. and D. Ward, "Bidirectional Forwarding Detection
              (BFD) for IPv4 and IPv6 (Single Hop)", RFC 5881,
              DOI 10.17487/RFC5881, June 2010,
              <https://www.rfc-editor.org/info/rfc5881>.

   [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>.

   [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>.

   [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>.

   [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>.

   [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>.

Rijsman, et al.          Expires August 26, 2021               [Page 32]
Internet-Draft               RIFT YANG Model               February 2021

   [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>.

   [RFC8177]  Lindem, A., Ed., Qu, Y., Yeung, D., Chen, I., and J.
              Zhang, "YANG Data Model for Key Chains", RFC 8177,
              DOI 10.17487/RFC8177, June 2017,
              <https://www.rfc-editor.org/info/rfc8177>.

   [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>.

   [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>.

   [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>.

   [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>.

   [RFC8349]  Lhotka, L., Lindem, A., and Y. Qu, "A YANG Data Model for
              Routing Management (NMDA Version)", RFC 8349,
              DOI 10.17487/RFC8349, March 2018,
              <https://www.rfc-editor.org/info/rfc8349>.

   [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>.

   [RFC8505]  Thubert, P., Ed., Nordmark, E., Chakrabarti, S., and C.
              Perkins, "Registration Extensions for IPv6 over Low-Power
              Wireless Personal Area Network (6LoWPAN) Neighbor
              Discovery", RFC 8505, DOI 10.17487/RFC8505, November 2018,
              <https://www.rfc-editor.org/info/rfc8505>.

Rijsman, et al.          Expires August 26, 2021               [Page 33]
Internet-Draft               RIFT YANG Model               February 2021

7.2.  Informative References

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

   [RFC8407]  Bierman, A., "Guidelines for Authors and Reviewers of
              Documents Containing YANG Data Models", BCP 216, RFC 8407,
              DOI 10.17487/RFC8407, October 2018,
              <https://www.rfc-editor.org/info/rfc8407>.

   [RFC8639]  Voit, E., Clemm, A., Gonzalez Prieto, A., Nilsen-Nygaard,
              E., and A. Tripathy, "Subscription to YANG Notifications",
              RFC 8639, DOI 10.17487/RFC8639, September 2019,
              <https://www.rfc-editor.org/info/rfc8639>.

   [RFC8641]  Clemm, A. and E. Voit, "Subscription to YANG Notifications
              for Datastore Updates", RFC 8641, DOI 10.17487/RFC8641,
              September 2019, <https://www.rfc-editor.org/info/rfc8641>.

Authors' Addresses

   Bruno Rijsman
   Individual

   Email: brunorijsman@gmail.com

   Zheng Zhang (editor)
   ZTE Corporation

   Email: zhang.zheng@zte.com.cn

   Yuehua Wei
   ZTE Corporation

   Email: wei.yuehua@zte.com.cn

   Shaowen Ma
   Google

   Email: mashaowen@gmail.com

Rijsman, et al.          Expires August 26, 2021               [Page 34]
Internet-Draft               RIFT YANG Model               February 2021

   Xufeng Liu
   Volta Networks

   Email: xufeng.liu.ietf@gmail.com

Rijsman, et al.          Expires August 26, 2021               [Page 35]