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YANG models for VN/TE Performance Monitoring Telemetry and Scaling Intent Autonomics
draft-ietf-teas-actn-pm-telemetry-autonomics-03

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Authors Young Lee , Dhruv Dhody , Satish Karunanithi , Ricard Vilalta , Daniel King , Daniele Ceccarelli
Last updated 2020-07-13
Replaces draft-lee-teas-actn-pm-telemetry-autonomics
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draft-ietf-teas-actn-pm-telemetry-autonomics-03
TEAS Working Group                                           Y. Lee, Ed.
Internet-Draft                                       Samsung Electronics
Intended status: Standards Track                           D. Dhody, Ed.
Expires: January 14, 2021                                 S. Karunanithi
                                                     Huawei Technologies
                                                              R. Vilalta
                                                                    CTTC
                                                                 D. King
                                                    Lancaster University
                                                           D. Ceccarelli
                                                                Ericsson
                                                           July 13, 2020

   YANG models for VN/TE Performance Monitoring Telemetry and Scaling
                           Intent Autonomics
            draft-ietf-teas-actn-pm-telemetry-autonomics-03

Abstract

   This document provides YANG data models that describe performance
   monitoring telemetry and scaling intent mechanism for TE-tunnels and
   Virtual Networks (VN).

   The models presented in this draft allow customers to subscribe to
   and monitor their key performance data of their interest on the level
   of TE-tunnel or VN.  The models also provide customers with the
   ability to program autonomic scaling intent mechanism on the level of
   TE-tunnel as well as VN.

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 January 14, 2021.

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Copyright Notice

   Copyright (c) 2020 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
   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 . . . . . . . . . . . . . . . . . . . . . . .   4
       1.1.1.  Requirements Language . . . . . . . . . . . . . . . .   4
     1.2.  Tree diagram  . . . . . . . . . . . . . . . . . . . . . .   4
     1.3.  Prefixes in Data Node Names . . . . . . . . . . . . . . .   5
   2.  Use-Cases . . . . . . . . . . . . . . . . . . . . . . . . . .   5
   3.  Design of the Data Models . . . . . . . . . . . . . . . . . .   7
     3.1.  TE KPI Telemetry Model  . . . . . . . . . . . . . . . . .   7
     3.2.  VN KPI Telemetry Model  . . . . . . . . . . . . . . . . .   8
   4.  Autonomic Scaling Intent Mechanism  . . . . . . . . . . . . .   9
   5.  Notification  . . . . . . . . . . . . . . . . . . . . . . . .  11
     5.1.  YANG Push Subscription Examples . . . . . . . . . . . . .  11
   6.  YANG Data Tree  . . . . . . . . . . . . . . . . . . . . . . .  12
   7.  YANG Data Model . . . . . . . . . . . . . . . . . . . . . . .  15
     7.1.  ietf-te-kpi-telemetry model . . . . . . . . . . . . . . .  15
     7.2.  ietf-vn-kpi-telemetry model . . . . . . . . . . . . . . .  21
   8.  Security Considerations . . . . . . . . . . . . . . . . . . .  25
   9.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  25
   10. Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  26
   11. References  . . . . . . . . . . . . . . . . . . . . . . . . .  26
     11.1.  Normative References . . . . . . . . . . . . . . . . . .  26
     11.2.  Informative References . . . . . . . . . . . . . . . . .  28
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  29

1.  Introduction

   The YANG [RFC7950] model discussed in [I-D.ietf-teas-actn-vn-yang] is
   used to operate customer-driven Virtual Networks (VNs) during the VN
   instantiation, VN computation, and its life-cycle service management
   and operations.  YANG model discussed in [I-D.ietf-teas-yang-te] is

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   used to operate TE-tunnels during the tunnel instantiation, and its
   life-cycle management and operations.

   The models presented in this draft allow the applications hosted by
   the customers to subscribe to and monitor their key performance data
   of their interest on the level of VN [I-D.ietf-teas-actn-vn-yang] or
   TE-tunnel [I-D.ietf-teas-yang-te].  The key characteristic of the
   models presented in this document is a top-down programmability that
   allows the applications hosted by the customers to subscribe to and
   monitor key performance data of their interest and autonomic scaling
   intent mechanism on the level of VN as well as TE-tunnel.

   According to the classification of [RFC8309], the YANG data models
   presented in this document can be classified as customer service
   models, which is mapped to CMI (Customer Network Controller (CNC)-
   Multi-Domain Service Coordinator (MSDC) interface) of ACTN [RFC8453].

   [RFC8233] describes key network performance data to be considered for
   end-to-end path computation in TE networks.  Key performance
   indicator (KPI) is a term that describes critical performance data
   that may affect VN/TE-tunnel service.  The services provided can be
   optimized to meet the requirements (such as traffic patterns,
   quality, and reliability) of the applications hosted by the
   customers.

   This document provides YANG data models generically applicable to any
   VN/TE-Tunnel service clients to provide an ability to program their
   customized performance monitoring subscription and publication data
   models and automatic scaling in/out intent data models.  These models
   can be utilized by a client network controller to initiate these
   capability to a transport network controller communicating with the
   client controller via a NETCONF [RFC8341] or a RESTCONF [RFC8040]
   interface.

   The term performance monitoring being used in this document is
   different from the term that has been used in transport networks for
   many years.  Performance monitoring in this document refers to
   subscription and publication of streaming telemetry data.
   Subscription is initiated by the client (e.g., CNC) while publication
   is provided by the network (e.g., MDSC/PNC) based on the client's
   subscription.  As the scope of performance monitoring in this
   document is telemetry data on the level of client's VN or TE- tunnel,
   the entity interfacing the client (e.g., MDSC) has to provide VN or
   TE-tunnel level information.  This would require controller
   capability to derive VN or TE-tunnel level performance data based on
   lower-level data collected via PM counters in the Network Elements
   (NE).  How the controller entity derives such customized level data
   (i.e., VN or TE-tunnel level) is out of the scope of this document.

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   The data model includes configuration and state data according to the
   new Network Management Datastore Architecture [RFC8342].

1.1.  Terminology

   Refer to [RFC8453], [RFC7926], and [RFC8309] for the key terms used
   in this document.

   Key Performance Data: This refers to a set of data the customer is
   interested in monitoring for their instantiated VNs or TE-tunnels.
   Key performance data and key performance indicators are inter-
   exchangeable in this draft.

   Scaling: This refers to the network ability to re-shape its own
   resources.  Scale out refers to improve network performance by
   increasing the allocated resources, while scale in refers to decrease
   the allocated resources, typically because the existing resources are
   unnecessary.

   Scaling Intent: To declare scaling conditions, scaling intent is
   used.  Specifically, scaling intent refers to the intent expressed by
   the client that allows the client to program/configure conditions of
   their key performance data either for scaling out or scaling in.
   Various conditions can be set for scaling intent on either VN or TE-
   tunnel level.

   Network Autonomics: This refers to the network automation capability
   that allows client to initiate scaling intent mechanisms and provides
   the client with the status of the adjusted network resources based on
   the client's scaling intent in an automated fashion.

1.1.1.  Requirements Language

   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.

1.2.  Tree diagram

   A simplified graphical representation of the data model is used in
   Section 5 of this this document.  The meaning of the symbols in these
   diagrams is defined in [RFC8340].

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1.3.  Prefixes in Data Node Names

   In this document, names of data nodes and other data model objects
   are prefixed using the standard prefix associated with the
   corresponding YANG imported modules, as shown in Table 1.

    +----------+-----------------------+------------------------------+
    | Prefix   | YANG module           | Reference                    |
    +----------+-----------------------+------------------------------+
    | inet     | ietf-inet-types       | [RFC6991]                    |
    | te       | ietf-te               | [I-D.ietf-teas-yang-te]      |
    | te-types | ietf-te-types         | [RFC8776]                    |
    | te-tel   | ietf-te-kpi-telemetry | [RFCXXXX]                    |
    | vn       | ietf-vn               | [I-D.ietf-teas-actn-vn-yang] |
    | vn-tel   | ietf-vn-kpi-telemetry | [RFCXXXX]                    |
    +----------+-----------------------+------------------------------+

             Table 1: Prefixes and corresponding YANG modules

   Note: The RFC Editor will replace XXXX with the number assigned to
   the RFC once this draft becomes an RFC.

   Further, the following additional documents are refrenced in the
   model defined in this document -

   o  [RFC7471] - OSPF Traffic Engineering (TE) Metric Extensions.

   o  [RFC8570] - IS-IS Traffic Engineering (TE) Metric Extensions.

   o  [RFC7823] - Performance-Based Path Selection for Explicitly Routed
      Label Switched Paths (LSPs) Using TE Metric Extensions.

2.  Use-Cases

   [I-D.xu-actn-perf-dynamic-service-control] describes use-cases
   relevant to this draft.  It introduces the dynamic creation,
   modification and optimization of services based on the performance
   monitoring.  Figure 1 shows a high-level workflows for dynamic
   service control based on traffic monitoring.

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      +----------------------------------------------+
      | Client   +-----------------------------+     |
      |          | Dynamic Service Control APP |     |
      |          +-----------------------------+     |
      +----------------------------------------------+
      1.Traffic|  /|\4.Traffic            | /|\
      Monitor& |   | Monitor              |  | 8.Traffic
      Optimize |   | Result     5.Service |  | modify &
      Policy   |   |              modify& |  | optimize
              \|/  |        optimize Req.\|/ | result
      +----------------------------------------------+
      | Orchestrator                                 |
      |    +-------------------------------+         |
      |    |Dynamic Service Control Agent  |         |
      |    +-------------------------------+         |
      |    +---------------+ +-------------------+   |
      |    | Flow Optimize | | vConnection Agent |   |
      |    +---------------+ +-------------------+   |
      +----------------------------------------------+
      2. Path |   /|\3.Traffic            | /|\
      Monitor |    | Monitor              |  |7.Path
      Request |    | Result      6.Path   |  | modify &
              |    |             modify&  |  | optimize
             \|/   |        optimize Req.\|/ | result
      +----------------------------------------------+
      | Network SDN Controller                       |
      |  +----------------------+ +-----------------+|
      |  | Network Provisioning | |Abstract Topology||
      |  +----------------------+ +-----------------+|
      |  +------------------+ +--------------------+ |
      |  |Network Monitoring| |Physical Topology DB| |
      |  +------------------+ +--------------------+ |
      +----------------------------------------------+

     Figure 1: Workflows for dynamic service control based on traffic
                                monitoring

   Some of the key points from
   [I-D.xu-actn-perf-dynamic-service-control] are as follows:

   o  Network traffic monitoring is important to facilitate automatic
      discovery of the imbalance of network traffic, and initiate the
      network optimization, thus helping the network operator or the
      virtual network service provider to use the network more
      efficiently and save the Capital Expense (CAPEX) and the Operating
      Expense (OPEX).

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   o  Customer services have various Service Level Agreement (SLA)
      requirements, such as service availability, latency, latency
      jitter, packet loss rate, Bit Error Rate (BER), etc.  The
      transport network can satisfy service availability and BER
      requirements by providing different protection and restoration
      mechanisms.  However, for other performance parameters, there are
      no such mechanisms.  In order to provide high quality services
      according to customer SLA, one possible solution is to measure the
      SLA related performance parameters, and dynamically provision and
      optimize services based on the performance monitoring results.

   o  Performance monitoring in a large scale network could generate a
      huge amount of performance information.  Therefore, the
      appropriate way to deliver the information in the client and
      network interfaces should be carefully considered.

3.  Design of the Data Models

   The YANG models developed in this document describe two models:

   (i)    TE KPI Telemetry Model which provides the TE-Tunnel level of
          performance monitoring mechanism and scaling intent mechanism
          that allows scale in/out programming by the customer.  (See
          Section 3.1 & Section 7.1 for details).

   (ii)   VN KPI Telemetry Model which provides the VN level of the
          aggregated performance monitoring mechanism and scaling intent
          mechanism that allows scale in/out programming by the customer
          (See Section 3.2 & Section 7.2 for details).

3.1.  TE KPI Telemetry Model

   This module describes performance telemetry for TE-tunnel model.  The
   telemetry data is augmented to tunnel state.  This module also allows
   autonomic traffic engineering scaling intent configuration mechanism
   on the TE-tunnel level.  Various conditions can be set for auto-
   scaling based on the telemetry data (See Section 5 for details)

   The TE KPI Telemetry Model augments the TE-Tunnel Model to enhance TE
   performance monitoring capability.  This monitoring capability will
   facilitate proactive re-optimization and reconfiguration of TEs based
   on the performance monitoring data collected via the TE KPI Telemetry
   YANG model.

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                +------------+          +--------------+
                |  TE-Tunnel |          |    TE KPI    |
                |   Model    |<---------|  Telemetry   |
                +------------+ augments |     Model    |
                                        +--------------+

3.2.  VN KPI Telemetry Model

   This module describes performance telemetry for VN model.  The
   telemetry data is augmented both at the VN Level as well as
   individual VN member level.  This module also allows autonomic
   traffic engineering scaling intent configuration mechanism on the VN
   level.  Scale in/out criteria might be used for network autonomics in
   order the controller to react to a certain set of variations in
   monitored parameters (See Section 4 for illustrations).

   Moreover, this module also provides mechanism to define aggregated
   telemetry parameters as a grouping of underlying VN level telemetry
   parameters.  Grouping operation (such as maximum, mean) could be set
   at the time of configuration.  For example, if maximum grouping
   operation is used for delay at the VN level, the VN telemetry data is
   reported as the maximum {delay_vn_member_1, delay_vn_member_2,..
   delay_vn_member_N}. Thus, this telemetry abstraction mechanism allows
   the grouping of a certain common set of telemetry values under a
   grouping operation.  This can be done at the VN-member level to
   suggest how the E2E telemetry be inferred from the per domain tunnel
   created and monitored by PNCs.  One proposed example is the
   following:

     +------------------------------------------------------------+
     |                      Client                                |
     |                                                            |
     +------------------------------------------------------------+
     1.Client sets the      |   /|\   2. Orchestrator pushes:
     grouping op, and       |    |
     subscribes to the      |    |    VN level telemetry for
     VN level telemetry for |    |    - VN Utilized-bw-percentage
     Delay and              |    |       (Minimum across VN Members)
     Utilized-bw-pecentage  |    |    - VN Delay (Maximum across VN
                           \|/   |     Members)
      +------------------------------------------------------------+
      | Orchestrator                                               |
      |                                                            |
      +------------------------------------------------------------+

   The VN Telemetry Model augments the basic VN model to enhance VN
   monitoring capability.  This monitoring capability will facilitate
   proactive re-optimization and reconfiguration of VNs based on the

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   performance monitoring data collected via the VN Telemetry YANG
   model.

                +----------+          +--------------+
                |    VN    | augments |      VN      |
                |   Model  |<---------|   Telemetry  |
                +----------+          |     Model    |
                                      +--------------+

4.  Autonomic Scaling Intent Mechanism

   Scaling intent configuration mechanism allows the client to configure
   automatic scale-in and scale-out mechanisms on both the TE-tunnel and
   the VN level.  Various conditions can be set for auto- scaling based
   on the PM telemetry data.

   There are a number of parameters involved in the mechanism:

   o  scale-out-intent or scale-in-intent: whether to scale-out or
      scale-in.

   o  performance-type: performance metric type (e.g., one-way-delay,
      one-way-delay-min, one-way-delay-max, two-way-delay, two-way-
      delay-min, two-way-delay-max, utilized bandwidth, etc.)

   o  threshold-value: the threshold value for a certain performance-
      type that triggers scale-in or scale-out.

   o  scaling-operation-type: in case where scaling condition can be set
      with one or more performance types, then scaling-operation-type
      (AND, OR, MIN, MAX, etc.) is applied to these selected performance
      types and its threshold values.

   o  Threshold-time: the duration for which the criteria MUST hold
      true.

   o  Cooldown-time: the duration after a scaling action has been
      triggered, for which there will be no further operation.

   The following tree is a part of ietf-te-kpi-telemetry tree whose
   model is presented in full detail in Sections 6 & 7.

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   module: ietf-te-kpi-telemetry
     augment /te:te/te:tunnels/te:tunnel:
       +--rw te-scaling-intent
       |  +--rw scale-in-intent
       |  |  +--rw threshold-time?      uint32
       |  |  +--rw cooldown-time?       uint32
       |  |  +--rw scaling-condition* [performance-type]
       |  |     +--rw performance-type           identityref
       |  |     +--rw threshold-value?           string
       |  |     +--rw scale-in-operation-type?
       |  |             scaling-criteria-operation
       |  +--rw scale-out-intent
       |     +--rw threshold-time?      uint32
       |     +--rw cooldown-time?       uint32
       |     +--rw scaling-condition* [performance-type]
       |        +--rw performance-type            identityref
       |        +--rw threshold-value?            string
       |        +--rw scale-out-operation-type?
       |                scaling-criteria-operation

   Let say the client wants to set the scaling out operation based on
   two performance-types (e.g., two-way-delay and utilized-bandwidth for
   a te-tunnel), it can be done as follows:

   o  Set Threshold-time: x (sec) (duration for which the criteria must
      hold true)

   o  Set Cooldown-time: y (sec) (the duration after a scaling action
      has been triggered, for which there will be no further operation)

   o  Set AND for the scale-out-operation-type

   In the scaling condition's list, the following two components can be
   set:

   List 1: Scaling Condition for Two-way-delay

   o  performance type: Two-way-delay

   o  threshold-value: z milli-seconds

   List 2: Scaling Condition for Utilized bandwidth

   o  performance type: Utilized bandwidth

   o  threshold-value: w megabytes

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5.  Notification

   This model does not define specific notifications.  To enable
   notifications, the mechanism defined in [RFC8641] and [RFC8640] can
   be used.  This mechanism currently allows the user to:

   o  Subscribe to notifications on a per client basis.

   o  Specify subtree filters or xpath filters so that only interested
      contents will be sent.

   o  Specify either periodic or on-demand notifications.

5.1.  YANG Push Subscription Examples

   [RFC8641] allows subscriber applications to request a continuous,
   customized stream of updates from a YANG datastore.

   Below example shows the way for a client to subscribe to the
   telemetry information for a particular tunnel (Tunnel1).  The
   telemetry parameter that the client is interested in is one-way-
   delay.

   <netconf:rpc netconf:message-id="101"
       xmlns:netconf="urn:ietf:params:xml:ns:netconf:base:1.0">
       <establish-subscription
          xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
          <filter netconf:type="subtree">
             <te xmlns="urn:ietf:params:xml:ns:yang:ietf-te">
                <tunnels>
                   <tunnel>
                     <name>Tunnel1</name>
                     <identifier/>
                     <state>
                       <te-telemetry xmlns="urn:ietf:params:xml:ns:yang:
                                            ietf-te-kpi-telemetry">
                           <one-way-delay/>
                        </te-telemetry>
                     </state>
                    </tunnel>
                 </tunnels>
             </te>
          </filter>
          <period>500</period>
          <encoding>encode-xml</encoding>
       </establish-subscription>
    </netconf:rpc>

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   This example shows the way for a client to subscribe to the telemetry
   information for all VNs.  The telemetry parameter that the client is
   interested in is one-way-delay and one-way-utilized- bandwidth.

   <netconf:rpc netconf:message-id="101"
       xmlns:netconf="urn:ietf:params:xml:ns:netconf:base:1.0">
       <establish-subscription
          xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push:1.0">
          <filter netconf:type="subtree">
             <vn-state xmlns="urn:ietf:params:xml:ns:yang:ietf-vn">
                <vn>
                   <vn-list>
                     <vn-id/>
                     <vn-name/>
                     <vn-telemetry xmlns="urn:ietf:params:xml:ns:yang:
                                           ietf-vn-kpi-telemetry">
                         <one-way-delay/>
                         <one-way-utilized-bandwidth/>
                     </vn-telemetry >
                   </vn-list>
                 </vn>
             </vn-state>
          </filter>
          <period>500</period>
       </establish-subscription>
    </netconf:rpc>

6.  YANG Data Tree

   module: ietf-te-kpi-telemetry
     augment /te:te/te:tunnels/te:tunnel:
       +--rw te-scaling-intent
       |  +--rw scale-in-intent
       |  |  +--rw threshold-time?      uint32
       |  |  +--rw cooldown-time?       uint32
       |  |  +--rw scaling-condition* [performance-type]
       |  |     +--rw performance-type           identityref
       |  |     +--rw threshold-value?           string
       |  |     +--rw scale-in-operation-type?
       |  |             scaling-criteria-operation
       |  +--rw scale-out-intent
       |     +--rw threshold-time?      uint32
       |     +--rw cooldown-time?       uint32
       |     +--rw scaling-condition* [performance-type]
       |        +--rw performance-type            identityref

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       |        +--rw threshold-value?            string
       |        +--rw scale-out-operation-type?
       |                scaling-criteria-operation
       +--ro te-telemetry
          +--ro id?                            telemetry-id
          +--ro performance-metrics-one-way
          |  +--ro one-way-delay?                           uint32
          |  +--ro one-way-delay-normality?
          |  |       te-types:performance-metrics-normality
          |  +--ro one-way-residual-bandwidth?
          |  |       rt-types:bandwidth-ieee-float32
          |  +--ro one-way-residual-bandwidth-normality?
          |  |       te-types:performance-metrics-normality
          |  +--ro one-way-available-bandwidth?
          |  |       rt-types:bandwidth-ieee-float32
          |  +--ro one-way-available-bandwidth-normality?
          |  |       te-types:performance-metrics-normality
          |  +--ro one-way-utilized-bandwidth?
          |  |       rt-types:bandwidth-ieee-float32
          |  +--ro one-way-utilized-bandwidth-normality?
          |          te-types:performance-metrics-normality
          +--ro performance-metrics-two-way
             +--ro two-way-delay?             uint32
             +--ro two-way-delay-normality?
                     te-types:performance-metrics-normality

   module: ietf-vn-kpi-telemetry
     augment /vn:vn/vn:vn-list:
       +--rw vn-scaling-intent
       |  +--rw scale-in-intent
       |  |  +--rw threshold-time?      uint32
       |  |  +--rw cooldown-time?       uint32
       |  |  +--rw scaling-condition* [performance-type]
       |  |     +--rw performance-type           identityref
       |  |     +--rw threshold-value?           string
       |  |     +--rw scale-in-operation-type?
       |  |             scaling-criteria-operation
       |  +--rw scale-out-intent
       |     +--rw threshold-time?      uint32
       |     +--rw cooldown-time?       uint32
       |     +--rw scaling-condition* [performance-type]
       |        +--rw performance-type            identityref
       |        +--rw threshold-value?            string
       |        +--rw scale-out-operation-type?
       |                scaling-criteria-operation

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       +--ro vn-telemetry
          +--ro performance-metrics-one-way
          |  +--ro one-way-delay?                           uint32
          |  +--ro one-way-delay-normality?
          |  |       te-types:performance-metrics-normality
          |  +--ro one-way-residual-bandwidth?
          |  |       rt-types:bandwidth-ieee-float32
          |  +--ro one-way-residual-bandwidth-normality?
          |  |       te-types:performance-metrics-normality
          |  +--ro one-way-available-bandwidth?
          |  |       rt-types:bandwidth-ieee-float32
          |  +--ro one-way-available-bandwidth-normality?
          |  |       te-types:performance-metrics-normality
          |  +--ro one-way-utilized-bandwidth?
          |  |       rt-types:bandwidth-ieee-float32
          |  +--ro one-way-utilized-bandwidth-normality?
          |          te-types:performance-metrics-normality
          +--ro performance-metrics-two-way
          |  +--ro two-way-delay?             uint32
          |  +--ro two-way-delay-normality?
          |          te-types:performance-metrics-normality
          +--ro grouping-operation?            grouping-operation
     augment /vn:vn/vn:vn-list/vn:vn-member-list:
       +--ro vn-member-telemetry
          +--ro performance-metrics-one-way
          |  +--ro one-way-delay?                           uint32
          |  +--ro one-way-delay-normality?
          |  |       te-types:performance-metrics-normality
          |  +--ro one-way-residual-bandwidth?
          |  |       rt-types:bandwidth-ieee-float32
          |  +--ro one-way-residual-bandwidth-normality?
          |  |       te-types:performance-metrics-normality
          |  +--ro one-way-available-bandwidth?
          |  |       rt-types:bandwidth-ieee-float32
          |  +--ro one-way-available-bandwidth-normality?
          |  |       te-types:performance-metrics-normality
          |  +--ro one-way-utilized-bandwidth?
          |  |       rt-types:bandwidth-ieee-float32
          |  +--ro one-way-utilized-bandwidth-normality?
          |          te-types:performance-metrics-normality
          +--ro performance-metrics-two-way
          |  +--ro two-way-delay?             uint32
          |  +--ro two-way-delay-normality?
          |          te-types:performance-metrics-normality
          +--ro te-grouped-params*
          |       -> /te:te/tunnels/tunnel/te-kpi:te-telemetry/id
          +--ro grouping-operation?            grouping-operation

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7.  YANG Data Model

7.1.  ietf-te-kpi-telemetry model

   The YANG code is as follows:

  <CODE BEGINS> file "ietf-te-kpi-telemetry@2020-07-13.yang"
 module ietf-te-kpi-telemetry {
   yang-version 1.1;
   namespace "urn:ietf:params:xml:ns:yang:ietf-te-kpi-telemetry";
   prefix te-tel;

   /* Import inet-types */

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

   /* Import TE */

   import ietf-te {
     prefix te;
     reference
       "I-D.ietf-teas-yang-te: A YANG Data Model for Traffic
        Engineering Tunnels and Interfaces";
   }

   /* Import TE Common types */

   import ietf-te-types {
     prefix te-types;
     reference
       "I-D.ietf-teas-yang-te-types: Traffic Engineering Common
        YANG Types";
   }

   organization
     "IETF Traffic Engineering Architecture and Signaling (TEAS)
      Working Group";
   contact
     "WG Web:  <https://tools.ietf.org/wg/teas/>
      WG List: <mailto:teas@ietf.org>
      Editor:  Young Lee <leeyoung@huawei.com>
               Dhruv Dhody <dhruv.ietf@gmail.com>";
   description
     "This module describes YANG data model for performance

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      monitoring telemetry for te tunnels.

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

   /* Note: The RFC Editor will replace XXXX with the number
      assigned to the RFC once draft-ietf-teas-pm-telemetry-
      autonomics becomes an RFC.*/

   revision 2020-03-08 {
     description
       "Initial revision.";
     reference
       "RFC XXXX: YANG models for VN/TE Performance Monitoring
        Telemetry and Scaling Intent Autonomics";
   }

   identity telemetry-param-type {
     description
       "Base identity for telemetry param types";
   }

   identity one-way-delay {
     base telemetry-param-type;
     description
       "To specify average Delay in one (forward)
        direction";
     reference
       "RFC7471: OSPF Traffic Engineering (TE) Metric Extensions.
        RFC8570: IS-IS Traffic Engineering (TE) Metric Extensions.
        RFC7823: Performance-Based Path Selection for Explicitly
        Routed Label Switched Paths (LSPs) Using TE Metric

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        Extensions";
   }

   identity two-way-delay {
     base telemetry-param-type;
     description
       "To specify average Delay in both (forward and reverse)
        directions";
     reference
       "RFC7471: OSPF Traffic Engineering (TE) Metric Extensions.
        RFC8570: IS-IS Traffic Engineering (TE) Metric Extensions.
        RFC7823: Performance-Based Path Selection for Explicitly
        Routed Label Switched Paths (LSPs) Using TE Metric
        Extensions";
   }

   identity one-way-delay-variation {
     base telemetry-param-type;
     description
       "To specify average Delay Variation in one (forward) direction";
     reference
       "RFC7471: OSPF Traffic Engineering (TE) Metric Extensions.
        RFC8570: IS-IS Traffic Engineering (TE) Metric Extensions.
        RFC7823: Performance-Based Path Selection for Explicitly
        Routed Label Switched Paths (LSPs) Using TE Metric
        Extensions";
   }

   identity two-way-delay-variation {
     base telemetry-param-type;
     description
       "To specify average Delay Variation in both (forward and reverse)
        directions";
     reference
       "RFC7471: OSPF Traffic Engineering (TE) Metric Extensions.
        RFC8570: IS-IS Traffic Engineering (TE) Metric Extensions.
        RFC7823: Performance-Based Path Selection for Explicitly
        Routed Label Switched Paths (LSPs) Using TE Metric
        Extensions";
   }

   identity utilized-bandwidth {
     base telemetry-param-type;
     description
       "To specify utilized bandwidth over the specified source
        and destination.";
     reference
       "RFC7471: OSPF Traffic Engineering (TE) Metric Extensions.

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        RFC8570: IS-IS Traffic Engineering (TE) Metric Extensions.
        RFC7823: Performance-Based Path Selection for Explicitly
        Routed Label Switched Paths (LSPs) Using TE Metric
        Extensions";
   }

   identity utilized-percentage {
     base telemetry-param-type;
     description
       "To specify utilization percentage of the entity
        (e.g., tunnel, link, etc.)";
   }

   /* Typedef */

   typedef telemetry-id {
     type inet:uri;
     description
       "Identifier for telemetry data.  The precise
        structure of the telemetry-id will be up to the
        implementation. The identifier SHOULD be chosen
        such that the same telemetry data will always be
        identified through the same identifier, even if
        the data model is instantiated in separate
        datastores.";
   }

   typedef scaling-criteria-operation {
     type enumeration {
       enum AND {
         description
           "AND operation";
       }
       enum OR {
         description
           "OR operation";
       }
     }
     description
       "Operations to analize list of scaling criterias";
   }

   grouping scaling-duration {
     description
       "Base scaling criteria durations";
     leaf threshold-time {
       type uint32;
       units "seconds";

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       description
         "The duration for which the criteria must hold true";
     }
     leaf cooldown-time {
       type uint32;
       units "seconds";
       description
         "The duration after a scaling-in/scaling-out action has been
          triggered, for which there will be no further operation";
     }
   }

   grouping scaling-criteria {
     description
       "Grouping for scaling criteria";
     leaf performance-type {
       type identityref {
         base telemetry-param-type;
       }
       description
         "Reference to the tunnel level telemetry type";
     }
     leaf threshold-value {
       type string;
       description
         "Scaling threshold for the telemetry parameter type";
     }
   }

   grouping scaling-in-intent {
     description
       "Basic scaling in intent";
     uses scaling-duration;
     list scaling-condition {
       key "performance-type";
       description
         "Scaling conditions";
       uses scaling-criteria;
       leaf scale-in-operation-type {
         type scaling-criteria-operation;
         default "AND";
         description
           "Operation to be applied to check between scaling criterias
            to check if the scale in threshold condition has been met.
            Defaults to AND";
       }
     }
   }

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   grouping scaling-out-intent {
     description
       "Basic scaling out intent";
     uses scaling-duration;
     list scaling-condition {
       key "performance-type";
       description
         "Scaling conditions";
       uses scaling-criteria;
       leaf scale-out-operation-type {
         type scaling-criteria-operation;
         default "OR";
         description
           "Operation to be applied to check between scaling criterias
            to check if the scale out threshold condition has been met.
            Defauls to OR";
       }
     }
   }

   augment "/te:te/te:tunnels/te:tunnel" {
     description
       "Augmentation parameters for config scaling-criteria TE
        tunnel topologies. Scale in/out criteria might be used
        for network autonomics in order the controller to react
        to a certain set of monitored params.";
     container te-scaling-intent {
       description
         "The scaling intent";
       container scale-in-intent {
         description
           "scale-in";
         uses scaling-in-intent;
       }
       container scale-out-intent {
         description
           "scale-out";
         uses scaling-out-intent;
       }
     }
     container te-telemetry {
       config false;
       description
         "Telemetry Data";
       leaf id {
         type telemetry-id;
         description
           "ID of telemetry data used for easy reference";

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       }
       uses te-types:performance-metrics-attributes;
     }
   }
 }

 <CODE ENDS>

7.2.  ietf-vn-kpi-telemetry model

   The YANG code is as follows:

  <CODE BEGINS> file "ietf-vn-kpi-telemetry@2020-07-13.yang"
  module ietf-vn-kpi-telemetry {
    yang-version 1.1;
    namespace "urn:ietf:params:xml:ns:yang:ietf-vn-kpi-telemetry";
    prefix vn-kpi;

    /* Import VN */

    import ietf-vn {
      prefix vn;
      reference
        "I-D.ietf-teas-actn-vn-yang: A YANG Data Model for VN
         Operation";
    }

    /* Import TE */

    import ietf-te {
      prefix te;
      reference
        "I-D.ietf-teas-yang-te: A YANG Data Model for Traffic
         Engineering Tunnels and Interfaces";
    }

    /* Import TE Common types */

    import ietf-te-types {
      prefix te-types;
      reference
        "RFC 8776: Common YANG Data Types for Traffic Engineering";
    }

    /* Import TE KPI */

    import ietf-te-kpi-telemetry {
      prefix te-kpi;

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      reference
        "RFC XXXX: YANG models for VN/TE Performance Monitoring
         Telemetry and Scaling Intent Autonomics";
    }

    /* Note: The RFC Editor will replace XXXX with the number
       assigned to this draft.*/

    organization
      "IETF Traffic Engineering Architecture and Signaling (TEAS)
       Working Group";
    contact
      "WG Web:  <https://tools.ietf.org/wg/teas/>
       WG List: <mailto:teas@ietf.org>
       Editor:  Young Lee <younglee.tx@gmail.com>
                Dhruv Dhody <dhruv.ietf@gmail.com>";
    description
      "This module describes YANG data models for performance
       monitoring telemetry for Virtual Network (VN).

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

    /* Note: The RFC Editor will replace XXXX with the number
       assigned to the RFC once draft-lee-teas-pm-telemetry-
       autonomics becomes an RFC.*/

    revision 2020-07-13 {
      description
        "Initial revision.";
      reference
        "RFC XXXX: YANG models for VN/TE Performance Monitoring

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         Telemetry and Scaling Intent Autonomics";
    }

    typedef grouping-operation {
      type enumeration {
        enum MINIMUM {
          description
            "Select the minimum param";
        }
        enum MAXIMUM {
          description
            "Select the maximum param";
        }
        enum MEAN {
          description
            "Select the MEAN of the params";
        }
        enum STD_DEV {
          description
            "Select the standard deviation of the monitored params";
        }
        enum AND {
          description
            "Select the AND of the params";
        }
        enum OR {
          description
            "Select the OR of the params";
        }
      }
      description
        "Operations to analize list of monitored params";
    }

    grouping vn-telemetry-param {
      description
        "augment of te-kpi:telemetry-param for VN specific params";
      leaf-list te-grouped-params {
        type leafref {
          path
            "/te:te/te:tunnels/te:tunnel/te-kpi:te-telemetry/te-kpi:id";
        }
        description
          "Allows the definition of a vn-telemetry param
           as a grouping of underlying TE params";
      }
      leaf grouping-operation {
        type grouping-operation;

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        description
          "describes the operation to apply to
           te-grouped-params";
      }
    }

    augment "/vn:vn/vn:vn-list" {
      description
        "Augmentation parameters for state TE VN topologies.";
      container vn-scaling-intent {
        description
          "scaling intent";
        container scale-in-intent {
          description
            "VN scale-in";
          uses te-kpi:scaling-in-intent;
        }
        container scale-out-intent {
          description
            "VN scale-out";
          uses te-kpi:scaling-out-intent;
        }
      }
      container vn-telemetry {
        config false;
        description
          "VN telemetry params";
        uses te-types:performance-metrics-attributes;
        leaf grouping-operation {
          type grouping-operation;
          description
            "describes the operation to apply to the VN-members";
        }
      }
    }

    augment "/vn:vn/vn:vn-list/vn:vn-member-list" {
      description
        "Augmentation parameters for state TE vn member topologies.";
      container vn-member-telemetry {
        config false;
        description
          "VN member telemetry params";
        uses te-types:performance-metrics-attributes;
        uses vn-telemetry-param;
      }
    }
  }

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  <CODE ENDS>

8.  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 users to a preconfigured
   subset of all available NETCONF protocol operations and content.  The
   NETCONF Protocol over Secure Shell (SSH) [RFC6242] describes a method
   for invoking and running NETCONF within a Secure Shell (SSH) session
   as an SSH subsystem.  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.

   A number of configuration data nodes defined in this document are
   writable/deletable (i.e., "config true").  These data nodes may be
   considered sensitive or vulnerable in some network environments.

   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.  These are the subtrees and data nodes
   and their sensitivity/vulnerability:

   o  /te:te/te:tunnels/te:tunnel/te-scaling-intent/scale-in-intent

   o  /te:te/te:tunnels/te:tunnel/te-scaling-intent/scale-out-intent

   o  /vn:vn/vn:vn-list/vn-scaling-intent/scale-in-intent

   o  /vn:vn/vn:vn-list/vn-scaling-intent/scale-out-intent

9.  IANA Considerations

   This document registers the following namespace URIs in the IETF XML
   registry [RFC3688]:

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   --------------------------------------------------------------------
   URI: urn:ietf:params:xml:ns:yang:ietf-te-kpi-telemetry
   Registrant Contact: The IESG.
   XML: N/A, the requested URI is an XML namespace.
   --------------------------------------------------------------------

   --------------------------------------------------------------------
   URI: urn:ietf:params:xml:ns:yang:ietf-vn-kpi-telemetry
   Registrant Contact: The IESG.
   XML: N/A, the requested URI is an XML namespace.
   --------------------------------------------------------------------

   This document registers the following YANG modules in the YANG
   Module.

   Names registry [RFC7950]:

   --------------------------------------------------------------------
   name:         ietf-te-kpi-telemetry
   namespace:    urn:ietf:params:xml:ns:yang:ietf-te-kpi-telemetry
   prefix:       te-tel
   reference:    RFC XXXX (TDB)
   --------------------------------------------------------------------

   --------------------------------------------------------------------
   name:         ietf-vn-kpi-telemetry
   namespace:    urn:ietf:params:xml:ns:yang:ietf-vn-kpi-telemetry
   prefix:       vn-tel
   reference:    RFC XXXX (TDB)
   --------------------------------------------------------------------

10.  Acknowledgements

   We thank Rakesh Gandhi, Tarek Saad, Igor Bryskin and Kenichi Ogaki
   for useful discussions and their suggestions for this work.

11.  References

11.1.  Normative References

   [I-D.ietf-teas-actn-vn-yang]
              Lee, Y., Dhody, D., Ceccarelli, D., Bryskin, I., and B.
              Yoon, "A Yang Data Model for VN Operation", draft-ietf-
              teas-actn-vn-yang-08 (work in progress), March 2020.

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   [I-D.ietf-teas-yang-te]
              Saad, T., Gandhi, R., Liu, X., Beeram, V., and I. Bryskin,
              "A YANG Data Model for Traffic Engineering Tunnels and
              Interfaces", draft-ietf-teas-yang-te-23 (work in
              progress), March 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>.

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

   [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>.

   [RFC7926]  Farrel, A., Ed., Drake, J., Bitar, N., Swallow, G.,
              Ceccarelli, D., and X. Zhang, "Problem Statement and
              Architecture for Information Exchange between
              Interconnected Traffic-Engineered Networks", BCP 206,
              RFC 7926, DOI 10.17487/RFC7926, July 2016,
              <https://www.rfc-editor.org/info/rfc7926>.

   [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>.

   [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>.

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   [RFC8233]  Dhody, D., Wu, Q., Manral, V., Ali, Z., and K. Kumaki,
              "Extensions to the Path Computation Element Communication
              Protocol (PCEP) to Compute Service-Aware Label Switched
              Paths (LSPs)", RFC 8233, DOI 10.17487/RFC8233, September
              2017, <https://www.rfc-editor.org/info/rfc8233>.

   [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>.

   [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>.

   [RFC8640]  Voit, E., Clemm, A., Gonzalez Prieto, A., Nilsen-Nygaard,
              E., and A. Tripathy, "Dynamic Subscription to YANG Events
              and Datastores over NETCONF", RFC 8640,
              DOI 10.17487/RFC8640, September 2019,
              <https://www.rfc-editor.org/info/rfc8640>.

   [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>.

   [RFC8776]  Saad, T., Gandhi, R., Liu, X., Beeram, V., and I. Bryskin,
              "Common YANG Data Types for Traffic Engineering",
              RFC 8776, DOI 10.17487/RFC8776, June 2020,
              <https://www.rfc-editor.org/info/rfc8776>.

11.2.  Informative References

   [I-D.xu-actn-perf-dynamic-service-control]
              Xu, Y., Zhang, G., Cheng, W., and z.
              zhenghaomian@huawei.com, "Use Cases and Requirements of
              Dynamic Service Control based on Performance Monitoring in
              ACTN Architecture", draft-xu-actn-perf-dynamic-service-
              control-03 (work in progress), April 2015.

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Internet-Draft            VN/TE Perf Monitoring                July 2020

   [RFC7471]  Giacalone, S., Ward, D., Drake, J., Atlas, A., and S.
              Previdi, "OSPF Traffic Engineering (TE) Metric
              Extensions", RFC 7471, DOI 10.17487/RFC7471, March 2015,
              <https://www.rfc-editor.org/info/rfc7471>.

   [RFC7823]  Atlas, A., Drake, J., Giacalone, S., and S. Previdi,
              "Performance-Based Path Selection for Explicitly Routed
              Label Switched Paths (LSPs) Using TE Metric Extensions",
              RFC 7823, DOI 10.17487/RFC7823, May 2016,
              <https://www.rfc-editor.org/info/rfc7823>.

   [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>.

   [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>.

   [RFC8570]  Ginsberg, L., Ed., Previdi, S., Ed., Giacalone, S., Ward,
              D., Drake, J., and Q. Wu, "IS-IS Traffic Engineering (TE)
              Metric Extensions", RFC 8570, DOI 10.17487/RFC8570, March
              2019, <https://www.rfc-editor.org/info/rfc8570>.

Authors' Addresses

   Young Lee (editor)
   Samsung Electronics

   Email: younglee.tx@gmail.com

   Dhruv Dhody (editor)
   Huawei Technologies
   Divyashree Techno Park, Whitefield
   Bangalore, Karnataka  560066
   India

   Email: dhruv.ietf@gmail.com

Lee, et al.             Expires January 14, 2021               [Page 29]
Internet-Draft            VN/TE Perf Monitoring                July 2020

   Satish Karunanithi
   Huawei Technologies
   Divyashree Techno Park, Whitefield
   Bangalore, Karnataka  560066
   India

   Email: satish.karunanithi@gmail.com

   Ricard Vilalta
   CTTC
   Centre Tecnologic de Telecomunicacions de Catalunya (CTTC/CERCA)
   Barcelona
   Spain

   Email: ricard.vilalta@cttc.es

   Daniel King
   Lancaster University

   Email: d.king@lancaster.ac.uk

   Daniele Ceccarelli
   Ericsson
   Torshamnsgatan,48
   Stockholm, Sweden

   Email: daniele.ceccarelli@ericsson.com

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