Skip to main content

YANG Data Model for SRv6 Base and Static
draft-ietf-spring-srv6-yang-03

Document Type Active Internet-Draft (spring WG)
Authors Syed Kamran Raza , Sonal Agarwal , Xufeng Liu , Zhibo Hu, Iftekhar Hussain , Himanshu C. Shah , Daniel Voyer , Hani Elmalky , Satoru Matsushima , Katsuhiro Horiba , Jaganbabu Rajamanickam , Ahmed Abdelsalam
Last updated 2024-03-04
Replaces draft-raza-spring-srv6-yang
RFC stream Internet Engineering Task Force (IETF)
Intended RFC status (None)
Formats
Yang Validation 0 errors, 0 warnings
Additional resources Yang catalog entry for ietf-srv6-base@2020-07-13.yang
Yang catalog entry for ietf-srv6-static@2020-07-13.yang
Yang catalog entry for ietf-srv6-types@2020-07-13.yang
Yang impact analysis for draft-ietf-spring-srv6-yang
Mailing list discussion
Stream WG state WG Document
Document shepherd (None)
IESG IESG state I-D Exists
Consensus boilerplate Unknown
Telechat date (None)
Responsible AD (None)
Send notices to (None)
draft-ietf-spring-srv6-yang-03
SPRING Working Group                                             K. Raza
Internet-Draft                                                S. Agarwal
Intended status: Standards Track                           Cisco Systems
Expires: 5 September 2024                                         X. Liu
                                                               Alef Edge
                                                                   Z. Hu
                                                     Huawei Technologies
                                                              I. Hussain
                                                    Infinera Corporation
                                                                 H. Shah
                                                       Ciena Corporation
                                                                D. Voyer
                                                             Bell Canada
                                                              H. Elmalky
                                                              Individual
                                                           S. Matsushima
                                                               K. Horiba
                                                                SoftBank
                                                         J. Rajamanickam
                                                           A. AbdelSalam
                                                           Cisco Systems
                                                            4 March 2024

                YANG Data Model for SRv6 Base and Static
                     draft-ietf-spring-srv6-yang-03

Abstract

   This document describes a YANG data model for Segment Routing IPv6
   (SRv6) base.  The model serves as a base framework for configuring
   and managing an SRv6 subsystem and expected to be augmented by other
   SRv6 technology models accordingly.  Additionally, this document also
   specifies the model for the SRv6 Static application.

   The YANG modules in this document conform to the Network Management
   Datastore Architecture (NMDA).

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/.

Raza, et al.            Expires 5 September 2024                [Page 1]
Internet-Draft          YANG Data Model for SRv6              March 2024

   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 5 September 2024.

Copyright Notice

   Copyright (c) 2024 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 Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Specification of Requirements . . . . . . . . . . . . . . . .   3
   3.  YANG Model  . . . . . . . . . . . . . . . . . . . . . . . . .   3
     3.1.  Overview  . . . . . . . . . . . . . . . . . . . . . . . .   4
     3.2.  SRv6 Types  . . . . . . . . . . . . . . . . . . . . . . .   4
     3.3.  SRv6 Base . . . . . . . . . . . . . . . . . . . . . . . .   5
       3.3.1.  Configuration . . . . . . . . . . . . . . . . . . . .   5
       3.3.2.  State . . . . . . . . . . . . . . . . . . . . . . . .   6
       3.3.3.  Notification  . . . . . . . . . . . . . . . . . . . .   8
     3.4.  SRv6 Static . . . . . . . . . . . . . . . . . . . . . . .   9
       3.4.1.  Configuration . . . . . . . . . . . . . . . . . . . .   9
       3.4.2.  State . . . . . . . . . . . . . . . . . . . . . . . .  15
       3.4.3.  Notification  . . . . . . . . . . . . . . . . . . . .  15
   4.  Pending Items . . . . . . . . . . . . . . . . . . . . . . . .  15
   5.  YANG Specification  . . . . . . . . . . . . . . . . . . . . .  15
     5.1.  SRv6 Types  . . . . . . . . . . . . . . . . . . . . . . .  15
     5.2.  SRv6 Base . . . . . . . . . . . . . . . . . . . . . . . .  31
     5.3.  SRv6 Static . . . . . . . . . . . . . . . . . . . . . . .  47
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  70
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  71
   8.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  72
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  72
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .  72
     9.2.  Informative References  . . . . . . . . . . . . . . . . .  74
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  74

Raza, et al.            Expires 5 September 2024                [Page 2]
Internet-Draft          YANG Data Model for SRv6              March 2024

1.  Introduction

   The Network Configuration Protocol (NETCONF) [RFC6241] is one of the
   network management protocols that defines mechanisms to manage
   network devices.  YANG [RFC6020] is a modular language that
   represents data structures in an XML tree format, and is used as a
   data modeling language for the NETCONF.

   Segment Routing (SR), as defined in [RFC8402], leverages the source
   routing paradigm where a node steers a packet through an ordered list
   of instructions, called segments.  SR, thus, allows enforcing a flow
   through any topological path and/or service chain while maintaining
   per-flow state only at the ingress nodes to the SR domain.  When
   applied to ipv6 data-plane (i.e.  SRv6), SR requires a type of
   routing header (SRH) in an IPv6 packet that is used to encode an
   ordered list of IPv6 addresses (SIDs).  The active segment is
   indicated by the Destination Address of the packet, and the next
   segment is indicated by a pointer in the SRH [RFC8754].  The various
   functions and behaviors corresponding to network programming using
   SRv6 are specified in [RFC8986].

   This document introduces a YANG data model for base SRv6 that would
   serve as a base framework for configuring and managing an SRv6
   subsystem.  As needed, other SRv6 technology models (e.g.  ISIS,
   OSPFv3, BGP, EVPN, Service Chaining) may augment this model.
   Furthermore, to illustrate basic behaviors as captured in [RFC8986],
   this document also specifies a YANG model for the SRv6-Static
   application.

   The model currently defines the following constructs that are used
   for managing SRv6:

   *  Configuration

   *  Operational State

   *  Notifications

2.  Specification of Requirements

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD 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.

3.  YANG Model

Raza, et al.            Expires 5 September 2024                [Page 3]
Internet-Draft          YANG Data Model for SRv6              March 2024

3.1.  Overview

   This document defines following three new YANG modules:

   *  ietf-srv6-types: defines common and basic types related to SRv6

   *  ietf-srv6-base: specifies management model for SRv6 base
      constructs (locator, SIDs, etc.)

   *  ietf-srv6-static: specifies management model for SRv6-static
      application

   The modeling in this document complies with the Network Management
   Datastore Architecture (NMDA) defined in [RFC8342].  The operational
   state data is combined with the associated configuration data in the
   same hierarchy [RFC8407].  When protocol states are retrieved from
   the NMDA operational state datastore, the returned states cover all
   "config true" (rw) and "config false" (ro) nodes defined in the
   schema.

   In this document, when a simplified graphical representation of YANG
   model is presented in a tree diagram, the meaning of the symbols in
   these tree diagrams is defined in [RFC8340].

3.2.  SRv6 Types

   SRv6 common types and definitions are defined in the new module
   "ietf-srv6-types".  The main types defined in this module include:

   *  srv6-sid: SRv6 SID

   *  srv6-func-value: Typedef for FUNC value in an SRv6 SID

   *  srv6-func-value-reserved-type: Enum (list) of "reserved" FUNC
      opcode

   *  srv6-endpoint-type: SRv6 Endpoint behaviors [RFC8986] identity
      type

   *  srv6-headend-type: SRv6 Headend behaviors [RFC8986] identity type

   *  srv6-security-type: SRv6 Security rules identity type

   *  srv6-counter-type: SRv6 Counters [RFC8986] identity type

   The corresponding YANG specification for this module is captured in
   Section 5.1.

Raza, et al.            Expires 5 September 2024                [Page 4]
Internet-Draft          YANG Data Model for SRv6              March 2024

3.3.  SRv6 Base

   The base SRv6 model is specified in ietf-srv6-base module.  This
   module augments "/rt:routing:/sr:segment-routing" [RFC9020] and
   specifies the configuration, operational state, and notification
   events that are required to manage the base SRv6.

   The corresponding YANG specification for this module is captured in
   Section 5.2.

3.3.1.  Configuration

   The module defines some fundamental items required to configure an
   SRv6 network:

   *  SRv6 Enablement: Enable Segment-Routing SRv6 feature

   *  Encapsulation Parameters: Provide encapsulation related parameters
      (such as source-address, hop-limit, and traffic-class) to be used
      when performing T.Encap* operation.

   *  Locator(s) Specification: SRv6 locator is a fundamental construct
      for an SRv6 network.  This is the construct from which SID
      (function values) are allocated that on the local box, and
      advertised to and used by remote nodes for reachability.  A
      locator is identified by a name and has associated prefix and IGP
      algorithm.  It can be configured as an anycast locator.  It is
      possible to have more than one locator on a node (e.g. locator per
      algorithm, anycast and non-anycast locators, etc.).

   Following is a simplified graphical tree representation of the data
   model for SRv6 base configuration

Raza, et al.            Expires 5 September 2024                [Page 5]
Internet-Draft          YANG Data Model for SRv6              March 2024

   module: ietf-srv6-base
     augment /rt:routing/sr:segment-routing:
       +--rw srv6
          +--rw enable?              boolean
          +--rw encapsulation
          |  +--rw source-address?   inet:ipv6-address
          |  +--rw hop-limit
          |  |  +--rw value?       uint8
          |  |  +--rw propagate?   boolean
          |  +--rw traffic-class
          |     +--rw value?       uint8
          |     +--rw propagate?   boolean
          +--rw locators
             +--rw locator* [name]
                +--rw name                      string
                +--rw enable?                   boolean
                +--rw prefix
                |  +--rw address    inet:ipv6-address
                |  +--rw length     srv6-types:srv6-locator-len
                +--rw algorithm?                uint32
                +--rw anycast?                  boolean

                     Figure 1: SRv6 Base - Config Tree

3.3.2.  State

   As per NMDA model, the state related to configuration items specified
   in above section Section 3.3.1 can be retrieved from the same tree.
   This section defines other operational state items related to SRv6
   base.

   The operational state corresponding to the SRv6 base includes:

   *  node capabilities: provides information on the node (hardware)
      capabilities and support regarding various SRv6 aspects and
      features including endpoint behaviors, headend behaviors, security
      rules, counter/stats support, and other SRv6 parameters that need
      to be signaled in an SRv6 network by the protocols.

   *  locator: provides information related to a locator.  The
      information includes locator operational state, and state of
      address conflict with any ipv6 address configured on local
      interfaces etc.

   *  local-sid: provides information related to local-SIDs allocated
      and/or installed on the node.  This includes two types of
      information:

Raza, et al.            Expires 5 September 2024                [Page 6]
Internet-Draft          YANG Data Model for SRv6              March 2024

      1.  aggregate across all local-SIDs such as aggregate counters

      2.  per local-SID information such as allocation type (dynamic or
          explicit), SID owner protocol(s)/client(s), forwarding [paths]
          information, and stats/counters.

   Following is a simplified graphical tree representation of the data
   model for the SRv6 operational state (for read-only items):

module: ietf-srv6-base
  augment /rt:routing/sr:segment-routing:
    +--rw srv6
       +--rw locators
       |  +--rw locator* [name]
       |     +--rw name                      string
       |     +--ro operational-status?       srv6-types:srv6-status-type
       |     +--ro is-in-address-conflict?   boolean
       +--ro node-capabilities
       |  +--ro end-behavior* [type]
       |  |  +--ro type         identityref
       |  |  +--ro supported    boolean
       |  +--ro headend-behavior* [type]
       |  |  +--ro type         identityref
       |  |  +--ro supported    boolean
       |  +--ro msd
       |  |  +--ro max-sl?        uint8
       |  |  +--ro max-end-pop?   uint8
       |  |  +--ro max-h_encap?   uint8
       |  |  +--ro max-end_d?     uint8
       |  +--ro security-rule* [type]
       |  |  +--ro type         identityref
       |  |  +--ro supported    boolean
       |  +--ro counters* [type]
       |     +--ro type         identityref
       |     +--ro supported    boolean
       +--ro local-sids
          +--ro counters
          |  +--ro cnt-3
          |     +--ro in-pkts?     yang:counter64
          |     +--ro in-octets?   yang:counter64
          +--ro local-sid* [sid]
             +--ro sid                  srv6-types:srv6-sid
             +--ro locator?             -> /rt:routing/sr:segment-routing/srv6:srv6/locators/locator/name
             +--ro is-reserved?         boolean
             +--ro end-behavior-type?   identityref
             +--ro alloc-type?          srv6-types:sid-alloc-type
             +--ro owner* [type instance]
             |  +--ro type         identityref

Raza, et al.            Expires 5 September 2024                [Page 7]
Internet-Draft          YANG Data Model for SRv6              March 2024

             |  +--ro instance     string
             |  +--ro is-winner?   boolean
             +--ro forwarding
             |  +--ro is-installed?    boolean
             |  +--ro next-hop-type?   srv6-types:srv6-nexthop-type
             |  +--ro paths
             |     +--ro path* [path-index]
             |        +--ro path-index    uint8
             |        +--ro l2
             |        |  +--ro interface?   if:interface-ref
             |        +--ro l3
             |        |  +--ro interface?           if:interface-ref
             |        |  +--ro next-hop?            inet:ip-address
             |        |  +--ro weight?              uint32
             |        |  +--ro role?                enumeration
             |        |  +--ro backup-path-index?   uint8
             |        +--ro (encap-type)?
             |           +--:(srv6)
             |           |  +--ro out-sid* [sid]
             |           |     +--ro sid    srv6-types:srv6-sid
             |           +--:(mpls)
             |              +--ro out-label* [label]
             |                 +--ro label    rt-types:mpls-label
             +--ro counters
                +--ro cnt-1
                   +--ro in-pkts?     yang:counter64
                   +--ro in-octets?   yang:counter64

                   Figure 2: SRv6 Base - State Tree

3.3.3.  Notification

   This model defines a list of notifications to inform an operator of
   important events detected during the SRv6 operation.  These events
   include events related to:

   *  locator operational state changes

   *  local-SID collision event

   Following is a simplified graphical tree representation of the data
   model for SRv6 notifications:

Raza, et al.            Expires 5 September 2024                [Page 8]
Internet-Draft          YANG Data Model for SRv6              March 2024

module: ietf-srv6-base

  notifications:
    +---n srv6-locator-status-event
    |  +--ro operational-status?   srv6-types:srv6-status-type
    |  +--ro locator?              -> /rt:routing/sr:segment-routing/srv6:srv6/locators/locator/name
    +---n srv6-sid-collision-event
       +--ro sid?         srv6-types:srv6-sid
       +--ro existing
       |  +--ro end-behavior-type?   identityref
       +--ro requested
          +--ro end-behavior-type?   identityref

               Figure 3: SRv6 Base - Notification Tree

3.4.  SRv6 Static

   SRv6-Static application allows a user to specify SRv6 local SIDs and
   program them in the forwarding plane.  The SRv6-Static model is
   captured in the ietf-srv6-static module.

   The associated YANG specification for this module is captured in
   Section 5.3.

3.4.1.  Configuration

   The SRv6-Static configuration augments the SRv6-base locator tree
   "/rt:routing/sr:segment-routing/srv6:srv6/srv6:locators/srv6:locator"

   Following are salient features of the SRv6-Static config model:

   *  Allows static (explicit) configuration for local-SIDs under a
      given locator.

   *  Given that entry is scoped under a locator, the key for each entry
      is "function" value.

   *  A user must also specify end-behavior type (End*) associated with
      the entry.

   *  A user must also specify behavior-specific data with each entry.
      For example, for any end behavior requiring a table lookup, a
      lookup-table need be provided.  Similarly, for any end behavior
      with forwarding next-hops need to specify next-hop information.
      The example of former include End, End.T, End.DT4, End.DT6, and
      End.DT46, whereas example of later include End.X, End.DX4,
      End.DX6, End.B6, End.BM etc.

Raza, et al.            Expires 5 September 2024                [Page 9]
Internet-Draft          YANG Data Model for SRv6              March 2024

   *  Each local-SID entry has zero or more forwarding paths specified.

   *  A forwarding path has next-hop type that depends on the end
      behavior, and could be either ipv6, or ipv4, or mpls, or l2 type.
      For example, End.X, End.DX4, End.DX6, End.B6, End.BM, and End.DX2
      will have ipv6, ipv4, ipv6, ipv6, mpls, and l2 next-hop types
      respectively

   *  For each forwarding next-hop type, the appropriate path attributes
      are to be specified as well.  For L2 type, the only other
      information required is the L2 interface name.  Whereas for L3
      (ipv6, ipv4, mpls) types, the information includes L3 interface
      name, next-hop IP address, weight, and protection information.

   *  Depending on the end behavior type, a forwarding path may have
      either MPLS or SRv6 encapsulation -- i.e., Stack of out-labels or
      Stack of SRv6 out-SIDs.  The example of former is End.BM and
      example of later include the rest (End.X, End.DX4, End.DX6, End.B6
      etc.).

   Following is a simplified graphical tree representation of the data
   model for SRv6 Static configuration

module: ietf-srv6-static
  augment /rt:routing/sr:segment-routing/srv6:srv6/srv6:locators/srv6:locator:
    +--rw static
       +--rw local-sids
          +--rw sid* [function]
             +--rw function             srv6-types:srv6-func-value
             +--rw end-behavior-type    identityref
             +--rw end
             +--rw end_psp
             +--rw end_usp
             +--rw end_psp_usp
             +--rw end_usd
             +--rw end_psp_usd
             +--rw end_usp_usd
             +--rw end_psp_usp_usd
             +--rw end-t
             |  +--rw lookup-table-ipv6    srv6-types:table-id
             +--rw end-t_psp
             |  +--rw lookup-table-ipv6    srv6-types:table-id
             +--rw end-t_usp
             |  +--rw lookup-table-ipv6    srv6-types:table-id
             +--rw end-t_psp_usp
             |  +--rw lookup-table-ipv6    srv6-types:table-id
             +--rw end-t_usd
             |  +--rw lookup-table-ipv6    srv6-types:table-id

Raza, et al.            Expires 5 September 2024               [Page 10]
Internet-Draft          YANG Data Model for SRv6              March 2024

             +--rw end-t_psp_usd
             |  +--rw lookup-table-ipv6    srv6-types:table-id
             +--rw end-t_usp_usd
             |  +--rw lookup-table-ipv6    srv6-types:table-id
             +--rw end-t_psp_usp_usd
             |  +--rw lookup-table-ipv6    srv6-types:table-id
             +--rw end-x
             |  +--rw protected?   boolean
             |  +--rw paths
             |     +--rw path* [path-index]
             |        +--rw path-index           uint8
             |        +--rw interface?           if:interface-ref
             |        +--rw next-hop?            inet:ipv6-address
             |        +--rw table?               srv6-types:table-id
             |        +--rw weight?              uint32
             |        +--rw role?                enumeration
             |        +--rw backup-path-index?   uint8
             |        +--rw sid-list
             |           +--rw out-sid* [sid]
             |              +--rw sid    srv6-types:srv6-sid
             +--rw end-x_psp
             |  +--rw protected?   boolean
             |  +--rw paths
             |     +--rw path* [path-index]
             |        +--rw path-index           uint8
             |        +--rw interface?           if:interface-ref
             |        +--rw next-hop?            inet:ipv6-address
             |        +--rw table?               srv6-types:table-id
             |        +--rw weight?              uint32
             |        +--rw role?                enumeration
             |        +--rw backup-path-index?   uint8
             |        +--rw sid-list
             |           +--rw out-sid* [sid]
             |              +--rw sid    srv6-types:srv6-sid
             +--rw end-x_usp
             |  +--rw protected?   boolean
             |  +--rw paths
             |     +--rw path* [path-index]
             |        +--rw path-index           uint8
             |        +--rw interface?           if:interface-ref
             |        +--rw next-hop?            inet:ipv6-address
             |        +--rw table?               srv6-types:table-id
             |        +--rw weight?              uint32
             |        +--rw role?                enumeration
             |        +--rw backup-path-index?   uint8
             |        +--rw sid-list
             |           +--rw out-sid* [sid]
             |              +--rw sid    srv6-types:srv6-sid

Raza, et al.            Expires 5 September 2024               [Page 11]
Internet-Draft          YANG Data Model for SRv6              March 2024

             +--rw end-x_psp_usp
             |  +--rw protected?   boolean
             |  +--rw paths
             |     +--rw path* [path-index]
             |        +--rw path-index           uint8
             |        +--rw interface?           if:interface-ref
             |        +--rw next-hop?            inet:ipv6-address
             |        +--rw table?               srv6-types:table-id
             |        +--rw weight?              uint32
             |        +--rw role?                enumeration
             |        +--rw backup-path-index?   uint8
             |        +--rw sid-list
             |           +--rw out-sid* [sid]
             |              +--rw sid    srv6-types:srv6-sid
             +--rw end-x_usd
             |  +--rw protected?   boolean
             |  +--rw paths
             |     +--rw path* [path-index]
             |        +--rw path-index           uint8
             |        +--rw interface?           if:interface-ref
             |        +--rw next-hop?            inet:ipv6-address
             |        +--rw table?               srv6-types:table-id
             |        +--rw weight?              uint32
             |        +--rw role?                enumeration
             |        +--rw backup-path-index?   uint8
             |        +--rw sid-list
             |           +--rw out-sid* [sid]
             |              +--rw sid    srv6-types:srv6-sid
             +--rw end-x_psp_usd
             |  +--rw protected?   boolean
             |  +--rw paths
             |     +--rw path* [path-index]
             |        +--rw path-index           uint8
             |        +--rw interface?           if:interface-ref
             |        +--rw next-hop?            inet:ipv6-address
             |        +--rw table?               srv6-types:table-id
             |        +--rw weight?              uint32
             |        +--rw role?                enumeration
             |        +--rw backup-path-index?   uint8
             |        +--rw sid-list
             |           +--rw out-sid* [sid]
             |              +--rw sid    srv6-types:srv6-sid
             +--rw end-x_usp_usd
             |  +--rw protected?   boolean
             |  +--rw paths
             |     +--rw path* [path-index]
             |        +--rw path-index           uint8
             |        +--rw interface?           if:interface-ref

Raza, et al.            Expires 5 September 2024               [Page 12]
Internet-Draft          YANG Data Model for SRv6              March 2024

             |        +--rw next-hop?            inet:ipv6-address
             |        +--rw table?               srv6-types:table-id
             |        +--rw weight?              uint32
             |        +--rw role?                enumeration
             |        +--rw backup-path-index?   uint8
             |        +--rw sid-list
             |           +--rw out-sid* [sid]
             |              +--rw sid    srv6-types:srv6-sid
             +--rw end-x_psp_usp_usd
             |  +--rw protected?   boolean
             |  +--rw paths
             |     +--rw path* [path-index]
             |        +--rw path-index           uint8
             |        +--rw interface?           if:interface-ref
             |        +--rw next-hop?            inet:ipv6-address
             |        +--rw table?               srv6-types:table-id
             |        +--rw weight?              uint32
             |        +--rw role?                enumeration
             |        +--rw backup-path-index?   uint8
             |        +--rw sid-list
             |           +--rw out-sid* [sid]
             |              +--rw sid    srv6-types:srv6-sid
             +--rw end-b6-encaps
             |  +--rw policy-name       string
             |  +--rw source-address    inet:ipv6-address
             |  +--rw paths
             |     +--rw path* [path-index]
             |        +--rw path-index           uint8
             |        +--rw interface?           if:interface-ref
             |        +--rw next-hop?            inet:ipv6-address
             |        +--rw table?               srv6-types:table-id
             |        +--rw weight?              uint32
             |        +--rw role?                enumeration
             |        +--rw backup-path-index?   uint8
             |        +--rw sid-list
             |           +--rw out-sid* [sid]
             |              +--rw sid    srv6-types:srv6-sid
             +--rw end-bm
             |  +--rw policy-name    string
             |  +--rw paths
             |     +--rw path* [path-index]
             |        +--rw path-index           uint8
             |        +--rw interface?           if:interface-ref
             |        +--rw next-hop?            inet:ip-address
             |        +--rw weight?              uint32
             |        +--rw role?                enumeration
             |        +--rw backup-path-index?   uint8
             |        +--rw sid-list

Raza, et al.            Expires 5 September 2024               [Page 13]
Internet-Draft          YANG Data Model for SRv6              March 2024

             |           +--rw out-sid* [sid]
             |              +--rw sid    srv6-types:srv6-sid
             +--rw end-dx6
             |  +--rw paths
             |     +--rw path* [path-index]
             |        +--rw path-index           uint8
             |        +--rw interface?           if:interface-ref
             |        +--rw next-hop?            inet:ipv6-address
             |        +--rw table?               srv6-types:table-id
             |        +--rw weight?              uint32
             |        +--rw role?                enumeration
             |        +--rw backup-path-index?   uint8
             |        +--rw sid-list
             |           +--rw out-sid* [sid]
             |              +--rw sid    srv6-types:srv6-sid
             +--rw end-dx4
             |  +--rw paths
             |     +--rw path* [path-index]
             |        +--rw path-index           uint8
             |        +--rw interface?           if:interface-ref
             |        +--rw next-hop?            inet:ipv4-address
             |        +--rw table?               srv6-types:table-id
             |        +--rw weight?              uint32
             |        +--rw role?                enumeration
             |        +--rw backup-path-index?   uint8
             |        +--rw sid-list
             |           +--rw out-sid* [sid]
             |              +--rw sid    srv6-types:srv6-sid
             +--rw end-dt6
             |  +--rw lookup-table-ipv6    srv6-types:table-id
             +--rw end-dt4
             |  +--rw lookup-table-ipv4    srv6-types:table-id
             +--rw end-dt46
             |  +--rw lookup-table-ipv4    srv6-types:table-id
             |  +--rw lookup-table-ipv6    srv6-types:table-id
             +--rw end-dx2
             |  +--rw path
             |     +--rw l2-interface    if:interface-ref
             +--rw end-dx2v
             |  +--rw lookup-table-vlan    srv6-types:table-id
             +--rw end-dt2u
             |  +--rw lookup-table-mac    srv6-types:table-id
             +--rw end-dt2m
                +--rw flooding-table    srv6-types:table-id
                +--rw paths
                   +--rw path* [path-index]
                      +--rw path-index      uint8
                      +--rw l2-interface?   if:interface-ref

Raza, et al.            Expires 5 September 2024               [Page 14]
Internet-Draft          YANG Data Model for SRv6              March 2024

                 Figure 4: SRv6 Static - Config Tree

3.4.2.  State

   As per NMDA model, the state related to configuration items specified
   in above section Section 3.4.1 can be retrieved from the same tree.
   The state regarding the local-SIDs created by SRv6-static model can
   be obtained using the state model of SRv6-base.  Hence, there is no
   additional state identified at this time for SRv6-static.

3.4.3.  Notification

   None.

4.  Pending Items

   Following are the items that will be addressed in next revisions:

   *  Extend local-SID collision event/notification in SRv6-base model.

   *  Add RPC support in the SRv6-base model.

   *  Add ARGS support in the SRv6-Static model.

   *  QoS support

5.  YANG Specification

   Following are actual YANG definition for SRv6 modules defined earlier
   in the document.

5.1.  SRv6 Types

   This YANG module imports types defined in [RFC6991].

   Moreover, the module models behaviors defined in [RFC8986],
   [I-D.ietf-spring-sr-service-programming], and [RFC9433].

   <CODE BEGINS> file "ietf-srv6-types@2022-01-14.yang"
   // RFC Editor: replace the above date with the date of
   // publication and remove this note.

   module ietf-srv6-types {
     yang-version 1.1;

     namespace "urn:ietf:params:xml:ns:yang:ietf-srv6-types";
     prefix srv6-types;

Raza, et al.            Expires 5 September 2024               [Page 15]
Internet-Draft          YANG Data Model for SRv6              March 2024

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

     organization
       "IETF SPRING Working Group";
     contact
       "WG Web:   <http://tools.ietf.org/wg/spring/>
        WG List:  <mailto:spring@ietf.org>

        Editor:   Kamran Raza
                  <mailto:skraza@cisco.com>

        Editor:   Jaganbabu Rajamanickam
                  <maito:jrajaman@cisco.com>

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

        Editor:   Zhibo Hu
                  <mailto:huzhibo@huawei.com>

        Editor:   Iftekhar Hussain
                  <mailto:IHussain@infinera.com>

        Editor:   Himanshu Shah
                  <mailto:hshah@ciena.com>

        Editor:   Daniel Voyer
                  <mailto:daniel.voyer@bell.ca>

        Editor:   Hani Elmalky
                  <mailto:helmalky@google.com>

        Editor:   Satoru Matsushima
                  <mailto:satoru.matsushima@gmail.com>

        Editor:   Katsuhiro Horiba
                  <mailto:katsuhiro.horiba@g.softbank.co.jp>

        Editor:   Ahmed AbdelSalam
                  <mailto:ahabdels@cisco.com>

        ";

     description
       "This YANG module defines the essential types for the

Raza, et al.            Expires 5 September 2024               [Page 16]
Internet-Draft          YANG Data Model for SRv6              March 2024

        management of Segment-Routing with IPv6 dataplane (SRv6).

        Copyright (c) 2018 IETF Trust and the persons identified as
        authors of the code.  All rights reserved.

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

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

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

     revision 2024-03-04 {
       description
         "Renamed some of End identities";
       reference
         "RFC XXXX: YANG Data Model for SRv6";
        // RFC Editor: replace XXXX with actual RFC number and remove
        // this note
     }

     revision 2022-01-14 {
       description
         "Alignment with SRv6 net-pgm rev16";
       reference
         "RFC XXXX: YANG Data Model for SRv6";
        // RFC Editor: replace XXXX with actual RFC number and remove
        // this note
     }

     revision 2019-10-30 {
       description
         "Renaming of some types";
       reference
         "RFC XXXX: YANG Data Model for SRv6";
        // RFC Editor: replace XXXX with actual RFC number and remove
        // this note
     }

     revision 2019-07-08 {
       description
         "Alignment with latest SRv6 network programming";

Raza, et al.            Expires 5 September 2024               [Page 17]
Internet-Draft          YANG Data Model for SRv6              March 2024

       reference
         "RFC XXXX: YANG Data Model for SRv6";
        // RFC Editor: replace XXXX with actual RFC number and remove
        // this note
     }

     revision 2018-10-22 {
       description
         "Initial revision.";
       reference
         "RFC XXXX: YANG Data Model for SRv6";
        // RFC Editor: replace XXXX with actual RFC number and remove
        // this note
     }

     identity srv6-endpoint-type {
         description
           "Base identity from which specific SRv6 Endpoint types are
           derived.";
     }

     /* Endpoints defined under draft-ietf-spring-
       * srv6-network-programming */

     identity End {
       base srv6-endpoint-type;
       description
             "End function (variant: no PSP, no USP).";
       reference
             "RFC 8986";
     }

     identity End_PSP {
       base srv6-endpoint-type;
       description
             "End function (variant: PSP only).";
       reference
             "RFC 8986";
     }

     identity End_USP {
       base srv6-endpoint-type;
       description
             "End function (variant: USP only).";
       reference
             "RFC 8986";
     }

Raza, et al.            Expires 5 September 2024               [Page 18]
Internet-Draft          YANG Data Model for SRv6              March 2024

     identity End_PSP_USP {
       base srv6-endpoint-type;
       description
             "End function (variant: PSP and USP).";
       reference
             "RFC 8986";
     }

     identity End.X {
       base srv6-endpoint-type;
       description
             "Endpoint with cross-connect to an array
              of layer-3 adjacencies (variant: no PSP, no USP).";
       reference
             "RFC 8986";
     }

     identity End.X_PSP {
       base srv6-endpoint-type;
       description
             "Endpoint with cross-connect to an array
              of layer-3 adjacencies (variant: PSP only).";
       reference
             "RFC 8986";
     }

     identity End.X_USP {
       base srv6-endpoint-type;
       description
             "Endpoint with cross-connect to an array
              of layer-3 adjacencies (variant: USP only).";
       reference
             "RFC 8986";
     }

     identity End.X_PSP_USP {
       base srv6-endpoint-type;
       description
             "Endpoint with cross-connect to an array
              of layer-3 adjacencies (variant: PSP and USP).";
       reference
             "RFC 8986";
     }

     identity End.T {
       base srv6-endpoint-type;
       description
             "Endpoint with specific IPv6 table lookup

Raza, et al.            Expires 5 September 2024               [Page 19]
Internet-Draft          YANG Data Model for SRv6              March 2024

             (variant: no PSP, no USP).";
       reference
             "RFC 8986";
     }

     identity End.T_PSP {
       base srv6-endpoint-type;
       description
             "Endpoint with specific IPv6 table lookup
             (variant: PSP only).";
       reference
             "RFC 8986";
     }

     identity End.T_USP {
       base srv6-endpoint-type;
       description
             "Endpoint with specific IPv6 table lookup
              (variant: USP only).";
       reference
             "RFC 8986";
     }

     identity End.T_PSP_USP {
       base srv6-endpoint-type;
       description
             "Endpoint with specific IPv6 table lookup
              (variant: PSP and USP).";
       reference
             "RFC 8986";
     }

     identity End.B6.Encaps {
       base srv6-endpoint-type;
       description
            "Endpoint bound to an SRv6 Policy
             where the SRv6 Policy also includes an
             IPv6 Source Address A.";
       reference
             "RFC 8986";
      }

      identity End.BM {
        base srv6-endpoint-type;
        description
             "Endpoint bound to an SR-MPLS Policy";
       reference
             "RFC 8986";

Raza, et al.            Expires 5 September 2024               [Page 20]
Internet-Draft          YANG Data Model for SRv6              March 2024

      }

      identity End.DX6 {
        base srv6-endpoint-type;
        description
             "Endpoint with decapsulation and cross-connect
              to an array of IPv6 adjacencies";
        reference
             "RFC 8986";
      }

      identity End.DX4 {
        base srv6-endpoint-type;
        description
             "Endpoint with decapsulation and cross-connect
              to an array of IPv4 adjacencies";
        reference
             "RFC 8986";
      }

      identity End.DT6 {
        base srv6-endpoint-type;
        description
             "Endpoint with decapsulation and specific
              IPv6 table lookup";
        reference
             "RFC 8986";
      }

      identity End.DT4 {
        base srv6-endpoint-type;
        description
             "Endpoint with decapsulation and specific
              IPv4 table lookup";
        reference
             "RFC 8986";
      }

      identity End.DT46 {
        base srv6-endpoint-type;
        description
             "Endpoint with decapsulation and specific IP
              (IPv4 or IPv6) table lookup";
        reference
             "RFC 8986";
      }

      identity End.DX2 {

Raza, et al.            Expires 5 September 2024               [Page 21]
Internet-Draft          YANG Data Model for SRv6              March 2024

        base srv6-endpoint-type;
        description
             "Endpoint with decapsulation and Layer-2
              cross-connect to an L2 interface";
        reference
             "RFC 8986";
      }

      identity End.DX2V {
        base srv6-endpoint-type;
        description
             "Endpoint with decapsulation and specific
              VLAN L2 table lookup";
        reference
             "RFC 8986";
      }

      identity End.DT2U {
        base srv6-endpoint-type;
        description
             "Endpoint with decapsulation and specific
              unicast MAC L2 table lookup";
        reference
             "RFC 8986";
      }

      identity End.DT2M {
        base srv6-endpoint-type;
        description
             "Endpoint with decapsulation and specific L2 table
              flooding";
        reference
             "RFC 8986";
      }

      identity End.B6.Encaps.Red {
        base srv6-endpoint-type;
        description
             "This is a reduced encap variation of the End.B6.Encap
             behavior.";
        reference
             "RFC 8986";
      }

      identity End_USD {
        base srv6-endpoint-type;
        description
             "End function (variant: USD).";

Raza, et al.            Expires 5 September 2024               [Page 22]
Internet-Draft          YANG Data Model for SRv6              March 2024

        reference
             "RFC 8986";
      }

      identity End_PSP_USD {
        base srv6-endpoint-type;
        description
             "End function (variant: PSP and USD).";
        reference
             "RFC 8986";
      }

      identity End_USP_USD {
        base srv6-endpoint-type;
        description
             "End function (variant: USP and USD).";
        reference
             "RFC 8986";
      }

      identity End_PSP_USP_USD {
        base srv6-endpoint-type;
        description
             "End function (variant: PSP and USP and USD).";
        reference
             "RFC 8986";
      }

      identity End.X_USD {
        base srv6-endpoint-type;
        description
             "Endpoint with cross-connect to an array
              of layer-3 adjacencies (variant: USD).";
        reference
             "RFC 8986";
      }

      identity End.X_PSP_USD {
        base srv6-endpoint-type;
        description
             "Endpoint with cross-connect to an array
              of layer-3 adjacencies (variant: PSP and USD).";
        reference
             "RFC 8986";
      }

      identity End.X_USP_USD {
        base srv6-endpoint-type;

Raza, et al.            Expires 5 September 2024               [Page 23]
Internet-Draft          YANG Data Model for SRv6              March 2024

        description
             "Endpoint with cross-connect to an array
              of layer-3 adjacencies (variant: USP and USD).";
        reference
             "RFC 8986";
      }

      identity End.X_PSP_USP_USD {
        base srv6-endpoint-type;
        description
             "Endpoint with cross-connect to an array
              of layer-3 adjacencies (variant: PSP and USP and USD).";
        reference
             "RFC 8986";
      }

      identity End.T_USD {
        base srv6-endpoint-type;
        description
             "Endpoint with decapsulation and Layer-2
              cross-connect to an L2 interface";
        reference
             "RFC 8986";
      }

      identity End.T_PSP_USD {
        base srv6-endpoint-type;
        description
             "Endpoint with specific IPv6 table lookup
              (variant: PSP and USD).";
        reference
             "RFC 8986";
      }

      identity End.T_USP_USD {
        base srv6-endpoint-type;
        description
             "Endpoint with specific IPv6 table lookup
              (variant: USP and USD).";
        reference
             "RFC 8986";
      }

      identity End.T_PSP_USP_USD {
        base srv6-endpoint-type;
        description
             "Endpoint with specific IPv6 table lookup
              (variant: PSP and USP and USD).";

Raza, et al.            Expires 5 September 2024               [Page 24]
Internet-Draft          YANG Data Model for SRv6              March 2024

        reference
             "RFC 8986";
      }

      /* Endpoints defined under draft-ietf-spring-sr-service-programming */

      identity End.AN {
        base srv6-endpoint-type;
        description
           "Service-Chaining SR Aware function (native)";
        reference
             "draft-ietf-spring-sr-service-programming-05";
       // RFC Editor: replace with actual RFC number and remove this note
      }

      identity End.AS {
        base srv6-endpoint-type;
        description
           "Service-Chaining Static proxy";
        reference
             "draft-ietf-spring-sr-service-programming-05";
       // RFC Editor: replace with actual RFC number and remove this note
      }

      identity End.AD {
        base srv6-endpoint-type;
        description
            "Service-Chaining Dynamic proxy";
        reference
             "draft-ietf-spring-sr-service-programming-05";
       // RFC Editor: replace with actual RFC number and remove this note
      }

      identity End.AM {
        base srv6-endpoint-type;
        description
            "Service-Chaining Masquerading SR proxy";
         reference
             "draft-ietf-spring-sr-service-programming-05";
       // RFC Editor: replace with actual RFC number and remove this note
      }

      identity End.AM_NAT {
        base srv6-endpoint-type;
        description
            "Service-Chaining Masquerading SR proxy with NAT";
         reference
             "draft-ietf-spring-sr-service-programming-05";

Raza, et al.            Expires 5 September 2024               [Page 25]
Internet-Draft          YANG Data Model for SRv6              March 2024

       // RFC Editor: replace with actual RFC number and remove this note
      }

      identity End.AM_CACHE {
        base srv6-endpoint-type;
        description
            "Service-Chaining Masquerading SR proxy with Caching";
         reference
             "draft-ietf-spring-sr-service-programming-05";
       // RFC Editor: replace with actual RFC number and remove this note
      }

      identity End.AM_NAT_CACHE {
        base srv6-endpoint-type;
        description
            "Service-Chaining Masquerading SR proxy with NAT and Caching";
         reference
             "draft-ietf-spring-sr-service-programming-05";
       // RFC Editor: replace with actual RFC number and remove this note
      }

      /* Endpoints defined under RFC 9433 */

      identity End.MAP {
        base srv6-endpoint-type;
        description
            "DMM End.MAP";
         reference
             "RFC 9433";
      }

      identity End.Limit {
        base srv6-endpoint-type;
        description
            "DMM End.Limit";
         reference
             "RFC 9433";
      }

      identity End.M.GTP6.D {
        base srv6-endpoint-type;
        description
            "DMM End.M.GTP6.D";
         reference
             "RFC 9433";
      }

      identity End.M.GTP6.Di {

Raza, et al.            Expires 5 September 2024               [Page 26]
Internet-Draft          YANG Data Model for SRv6              March 2024

        base srv6-endpoint-type;
        description
            "DMM End.M.GTP6.Di";
         reference
             "RFC 9433";
      }

      identity End.M.GTP6.E {
        base srv6-endpoint-type;
        description
            "DMM End.M.GTP6.E";
         reference
             "RFC 9433";
      }

      identity End.M.GTP4.E {
        base srv6-endpoint-type;
        description
            "DMM End.M.GTP4.E";
         reference
             "RFC 9433";
      }
      /* DMM end */

      identity srv6-headend-type {
        description
           "Base identity from which SRv6 headend rule types are derived.";
      }

      identity H.Encaps {
        base srv6-headend-type;
        description
            "Headend rule H.Encaps with encapsulated of an SRv6 policy";
        reference
             "draft-ietf-spring-srv6-network-programming-16";
       // RFC Editor: replace with actual RFC number and remove this note
      }

      identity H.Encaps.Red {
        base srv6-headend-type;
        description
            "Headend rule H.Encaps.Red with reduced encap of an
            SRv6 policy";
        reference
             "draft-ietf-spring-srv6-network-programming-16";
       // RFC Editor: replace with actual RFC number and remove this note
      }

Raza, et al.            Expires 5 September 2024               [Page 27]
Internet-Draft          YANG Data Model for SRv6              March 2024

      identity H.Encaps.L2 {
        base srv6-headend-type;
        description
            "Headend rule H.Encaps.l2 on the received L2 frame";
        reference
             "draft-ietf-spring-srv6-network-programming-16";
       // RFC Editor: replace with actual RFC number and remove this note
      }

      identity H.Encaps.L2.Red {
        base srv6-headend-type;
        description
            "Headend rule H.Encaps.L2.Red on the received L2 frame";
        reference
             "draft-ietf-spring-srv6-network-programming-16";
       // RFC Editor: replace with actual RFC number and remove this note
      }

     identity srv6-security-type {
        description
           "Base identity from which SRv6 Security rule types are
           derived.";
     }

     identity SEC-1 {
        base srv6-security-type;
        description
            "Support an ACL on the external interface that
             drops any traffic with SA or DA in the internal SID space.
             (aka Security rule SEC-1)";
      }

     identity SEC-2 {
        base srv6-security-type;
        description
            "Support an ACL that drops any traffic on local SID as DA
             from a source SA that does not belong to internal address
             or SID space. (aka Security rule SEC-2)";
     }

     identity srv6-counter-type {
        description
           "Base identity from which SRv6 counter types are derived.";
     }

     identity LocalSID {
        base srv6-counter-type;

Raza, et al.            Expires 5 September 2024               [Page 28]
Internet-Draft          YANG Data Model for SRv6              March 2024

        description
            "Count packets and bytes traffic that matched that SID and
             was processed successfully (aka Counter CNT-1)";
        reference
             "RFC 8986";
       // RFC Editor: replace with actual RFC number and remove this note
      }

     typedef srv6-sid {
         type inet:ipv6-prefix;
         description
         "This type defines a SID value in SRv6";
     }

     typedef srv6-func-value {
         type uint32;
         description
           "This is a typedef for SID's FUNC value";
     }

     typedef srv6-func-value-reserved-type {
         type enumeration {
           enum invalid {  value 0; description "Invalid function value"; }
         }

         description "SRv6 SID's FUNC Reserved values";
     }

     typedef srv6-locator-len {
         type uint8 {
           range "32 .. 96";
         }
         description
            "This type defines an SRv6 locator len with range constraints";
     }

     typedef srv6-sid-pfxlen {
         type uint8 {
           range "32 .. 128";
         }
         default 128;
         description
         "This type defines a SID prefixlen with range constraints";
     }

    typedef sid-alloc-type {
       type enumeration {

Raza, et al.            Expires 5 September 2024               [Page 29]
Internet-Draft          YANG Data Model for SRv6              March 2024

         enum Dynamic {
           description
             "SID allocated dynamically.";
         }
         enum Explicit {
           description
             "SID allocated with explicit (static) value";
         }
       }
       description
         "Types of sid allocation used.";
     }

     identity srv6-sid-owner-type {
         description
           "Base identity from which SID owner types are derived.";
     }

     identity isis {
         base srv6-sid-owner-type;
         description "ISIS";
     }

     identity ospfv3 {
         base srv6-sid-owner-type;
         description "OSPFv3";
     }

     identity bgp {
         base srv6-sid-owner-type;
         description "BGP";
     }

     identity evpn {
         base srv6-sid-owner-type;
         description "EVPN";
     }

     identity sr-policy {
         base srv6-sid-owner-type;
         description "SR Policy";
     }

     identity service-function {
         base srv6-sid-owner-type;
         description "SF";
     }

Raza, et al.            Expires 5 September 2024               [Page 30]
Internet-Draft          YANG Data Model for SRv6              March 2024

     typedef table-id {
       type uint32;
       description
         "Routing/switching/bridging/VLAN Table Id";
     }

     typedef srv6-status-type {
       type enumeration {
        enum up { value 1; description "State is Up"; }
        enum down { description "State is Down"; }
       }
       description
         "Status type";
     }

     typedef srv6-nexthop-type {
       type enumeration {
        enum ipv4 { value 1; description "IPv4 next-hop"; }
        enum ipv6 { description "IPv6 next-hop"; }
        enum mpls { description "MPLS next-hop"; }
        enum l2 { description "L2 next-hop"; }
       }
       description
         "Forwarding Next-hop type";
     }

   } // module
   <CODE ENDS>

                       Figure 5: ietf-srv6-types.yang

5.2.  SRv6 Base

   This YANG module imports types defined in [RFC6991], [RFC8294],
   [RFC8343], and [RFC8349].

   <CODE BEGINS> file "ietf-srv6-base@2022-01-14.yang"
   // RFC Editor: replace the above date with the date of
   // publication and remove this note.

   module ietf-srv6-base {
     yang-version 1.1;

     namespace "urn:ietf:params:xml:ns:yang:ietf-srv6-base";
     prefix srv6;

     import ietf-interfaces {
       prefix "if";

Raza, et al.            Expires 5 September 2024               [Page 31]
Internet-Draft          YANG Data Model for SRv6              March 2024

       reference "RFC 8343: A YANG Data Model for Interface Management";
     }

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

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

     import ietf-segment-routing {
       prefix sr;
       reference "draft-ietf-spring-sr-yang";
     }

     import ietf-srv6-types {
       prefix srv6-types;
       reference "RFC XXXX: YANG Data Model for SRv6";
       // RFC Editor: replace XXXX with actual RFC number and remove
       // this note
     }

     organization
       "IETF SPRING Working Group";
     contact
         "WG Web:   <http://tools.ietf.org/wg/spring/>
        WG List:  <mailto:spring@ietf.org>

        Editor:   Kamran Raza
                  <mailto:skraza@cisco.com>

        Editor:   Jaganbabu Rajamanickam
                  <maito:jrajaman@cisco.com>

Raza, et al.            Expires 5 September 2024               [Page 32]
Internet-Draft          YANG Data Model for SRv6              March 2024

        Editor:   Xufeng Liu
                  <mailto:Xufeng_Liu@jabil.com>

        Editor:   Zhibo Hu
                  <mailto:huzhibo@huawei.com>

        Editor:   Iftekhar Hussain
                  <mailto:IHussain@infinera.com>

        Editor:   Himanshu Shah
                  <mailto:hshah@ciena.com>

        Editor:   Daniel Voyer
                  <mailto:daniel.voyer@bell.ca>

        Editor:   Hani Elmalky
                  <mailto:helmalky@google.com>

        Editor:   Satoru Matsushima
                  <mailto:satoru.matsushima@gmail.com>

        Editor:   Katsuhiro Horiba
                  <mailto:katsuhiro.horiba@g.softbank.co.jp>

        Editor:   Ahmed AbdelSalam
                  <mailto:ahabdels@cisco.com>

        ";

     description
       "This YANG module defines the essential elements for the
        management of Segment-Routing with IPv6 dataplane (SRv6).

        Copyright (c) 2017 IETF Trust and the persons identified as
        authors of the code.  All rights reserved.

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

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

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

Raza, et al.            Expires 5 September 2024               [Page 33]
Internet-Draft          YANG Data Model for SRv6              March 2024

     revision 2022-01-14 {
       description
         "Alignment with SRv6 network programming rev16";
       reference
         "RFC XXXX: YANG Data Model for SRv6";
       // RFC Editor: replace XXXX with actual RFC number and remove
       // this note
     }

     revision 2019-10-30 {
       description
         "Alignment with SRv6 network programming";
       reference
         "RFC XXXX: YANG Data Model for SRv6";
       // RFC Editor: replace XXXX with actual RFC number and remove
       // this note
     }

     revision 2019-07-08 {
       description
         "Alignment with SRv6 network programming";
       reference
         "RFC XXXX: YANG Data Model for SRv6";
       // RFC Editor: replace XXXX with actual RFC number and remove
       // this note
     }

     revision 2018-10-22 {
       description
         "Initial revision.";
       reference
         "RFC XXXX: YANG Data Model for SRv6";
       // RFC Editor: replace XXXX with actual RFC number and remove
       // this note
     }

   /*
    * Common
    */

     grouping path-attrs-cmn {
        description
          "Path properties -common for v4/v6";

        leaf weight {
          type uint32;
          description
            "This value is used to compute a loadshare to perform un-equal

Raza, et al.            Expires 5 September 2024               [Page 34]
Internet-Draft          YANG Data Model for SRv6              March 2024

             load balancing when multiple outgoing path(s) are specified. A
             share is computed as a ratio of this number to the total under
             all configured path(s).";
        }

        leaf role {
          type enumeration {
            enum PRIMARY { description "Path as primary traffic carrying"; }
            enum BACKUP { description "Path acts as a backup"; }
            enum PRIMARY_AND_BACKUP {
              description "Path acts as primary and backup simultaneously"; }
            }
            description "The path role";
         }

         leaf backup-path-index {
          type uint8;
          description "Index of the protecting (backup) path";
         }
      }

     grouping path-out-sids {
       description "Grouping for path's SID stack";

         list out-sid {
           key "sid";
           description "Out SID";

           leaf sid {
             type srv6-types:srv6-sid;
             description "SID value";
           }
         }
     }

     grouping path-out-labels {
       description "Grouping for path's label stack";

         list out-label {
           key "label";
           description "Out label";

           leaf label {
             type rt-types:mpls-label;
             description "Label value";
           }
         }

Raza, et al.            Expires 5 September 2024               [Page 35]
Internet-Draft          YANG Data Model for SRv6              March 2024

     }

    /*
     * Config and State
     */

     grouping srv6-encap {
      description "Grouping for encap param config.";

      container encapsulation {
         description "Configure encapsulation related parameters";
         leaf source-address {
           type inet:ipv6-address;
           description "Specify a source address (for T.Encap).
                        The address must locally exists and be routable";
         }
         container hop-limit {
           description "Configure IPv6 header's Hop-limit options";
           leaf value {
             type uint8;
             default 64;
             description "Set encapsulating outer IPv6 header's Hoplimit
                         field to specified value when doing
                         encapsulation";
           }

           leaf propagate {
             type boolean;
             default false;
             description "IP TTL/Hop-limit propagation from encapsulated
                         packet to encapsulating outer IPv6 header's
                         Hoplimit field. When configured on decapsulation
                         side, this refers to propagating Hop-limit from
                         outer IPv6 header to inner header after decap";
           }
         }

         container traffic-class {
           description "Configure IPv6 header's Traffic-class options";
           leaf value {
             type uint8;
             default 0;
             description "Set encapsulating outer IPv6 header's
                         Traffic-class field to specified value when
                         doing encapsulation";
           }

           leaf propagate {

Raza, et al.            Expires 5 September 2024               [Page 36]
Internet-Draft          YANG Data Model for SRv6              March 2024

             type boolean;
             default false;
             description "Propagate (or map) Traffic-class/CoS/PCP from
                         the incoming packet or L2 Ethernet frame being
                         encapsulated to the encapsulating IPv6 header's
                         Traffic-class field.";
           }
         }

       }
     }

     grouping srv6-locator-state {
      description "SRv6 grouping Locator state";

          leaf operational-status {
            type srv6-types:srv6-status-type;
            config false;
            description "Indicates whether locator state is UP";
          }

          leaf is-in-address-conflict {
            type boolean;
            config false;
            description "Indicates whether locator address conflicts with
                         some other IPv6 address on the box";
          }
       }

     grouping srv6-locators {
      description "SRv6 locator grouping";

      container locators {
         description "SRv6 locators";

         list locator {
           key "name";
           description "Configure a SRv6 locator";

           leaf name {
             type string;
             description "Locator name";
           }

           leaf enable {
             type boolean;
             default false;
             description "Enable a SRv6 locator";

Raza, et al.            Expires 5 September 2024               [Page 37]
Internet-Draft          YANG Data Model for SRv6              March 2024

           }

           container prefix {
             description "Specify locator prefix value";
             leaf address {
               type inet:ipv6-address;
               mandatory true;
               description "IPv6 address";
             }
             leaf length {
               type srv6-types:srv6-locator-len;
               mandatory true;
               description "Locator (prefix) length";
             }
           }

           leaf algorithm {
             type uint32 {
               range "128..255";
             }

             description "Algorithm Id (for Flex-Algo)";
           }

           leaf anycast {
             type boolean;
             default false;
             description "Set to true if locator is an Anycast locator";
           }

           uses srv6-locator-state;
         }
       }
     }

     grouping srv6-stats-in {
       description "Grouping for inbound stats";

         leaf in-pkts {
           type yang:counter64;
           description
             "A cumulative counter of the total number of packets
             received";
         }

         leaf in-octets {
           type yang:counter64;
           description

Raza, et al.            Expires 5 September 2024               [Page 38]
Internet-Draft          YANG Data Model for SRv6              March 2024

             "A cumulative counter of the total bytes received.";
         }
     }

     grouping srv6-stats-out {
       description "Grouping for inbound stats";

         leaf out-pkts {
           type yang:counter64;
           description
             "A cumulative counter of the total number of packets
             transmitted";
         }

         leaf out-octets {
           type yang:counter64;
           description
             "A cumulative counter of the total bytes transmitted.";
         }
     }

     grouping path-out-sids-choice {
       description "Grouping for Out-SID choices";
       choice encap-type {
          description "Out-SID encap-based choice";
          case srv6 {
            uses path-out-sids;
          }
          case mpls {
            uses path-out-labels;
          }
       }
     }

     grouping local-sid-fwd-state {
       description "SRv6 local-SID forwarding state grouping";

       container forwarding {
          description "SRv6 local-SID forwarding state";

          leaf is-installed {
            type boolean;
            description "Indicates whether SID is installed in forwarding";
          }

          leaf next-hop-type {
            type srv6-types:srv6-nexthop-type;
            description "Forwarding next-hop types";

Raza, et al.            Expires 5 September 2024               [Page 39]
Internet-Draft          YANG Data Model for SRv6              March 2024

          }

          container paths {
            when "../is-installed = 'true'" {
              description "This container is valid only when the
              local-SID is installed in forwarding";
            }

            list path {
             key path-index;
             description "The list of paths associated with the SID";

             leaf path-index {
               type uint8;
               description "Index of the path";
             }

             container l2 {
               when "../../../next-hop-type = 'l2'" {
                 description "This container is valid only for L2 type
                    of NHs";
               }

               leaf interface {
                 type if:interface-ref;
                  description "The outgoing Layer2 interface";
               }

               description "L2 information";
             }

             container l3 {
               when "../../../next-hop-type != 'l2'" {
                 description "This container is valid only for L3 type
                     of NHs";
               }

               leaf interface {
                 type if:interface-ref;
                 description "The outgoing Layer3 interface";
               }

               leaf next-hop {
                 type inet:ip-address;
                 description "The IP address of the next-hop";
               }

               uses path-attrs-cmn;

Raza, et al.            Expires 5 September 2024               [Page 40]
Internet-Draft          YANG Data Model for SRv6              March 2024

               description "L3 information";
             }
             uses path-out-sids-choice;
           }

           description "Forwarding paths";
          }
       }
     }

     grouping srv6-state-sid {
      description "SRv6 SID state grouping";

      container local-sids {
        config false;
        description "Local-SID state";

        container counters {
            description "SRv6 counters";
            container cnt-3 {
              description "Counts SRv6 traffic received/dropped on local
              prefix not instantiated as local-SID";
              uses srv6-stats-in;
            }
        }

        list local-sid {
          key "sid";
          description "Per-localSID Counters";

          leaf sid {
           type srv6-types:srv6-sid;
           description "Local SID value";
          }

          uses srv6-locator;

          leaf is-reserved {
            type boolean;
            description "Set to true if SID comes from reserved pool";
          }

          leaf end-behavior-type {
              type identityref {
                base srv6-types:srv6-endpoint-type;
              }
              description "Type of SRv6 end behavior.";
          }

Raza, et al.            Expires 5 September 2024               [Page 41]
Internet-Draft          YANG Data Model for SRv6              March 2024

          leaf alloc-type {
           type srv6-types:sid-alloc-type;
           description
             "Type of sid allocation.";
          }

          list owner {
            key "type instance";
            description "SID Owner clients";
            leaf type {
              type identityref {
                base srv6-types:srv6-sid-owner-type;
              }
              description "SID owner/client type";
            }
            leaf instance {
              type string;
              description "Client instance";
            }
            leaf is-winner {
              type boolean;
              description "Is this client/owner the winning in terms of
              forwarding";
            }
          }

          uses local-sid-fwd-state;

          container counters {
            description "SRv6 per local-SID counters";

            container cnt-1 {
              description "Counts SRv6 traffic received on local-SID
              prefix and processed successfully";
              uses srv6-stats-in;
            }
          }
       }
      }
     }

     grouping srv6-support-ends {
       description "SRv6 End behavior support grouping";

      list end-behavior {
        key "type";
        description "End behavior support";

Raza, et al.            Expires 5 September 2024               [Page 42]
Internet-Draft          YANG Data Model for SRv6              March 2024

        leaf type {
          type identityref {
            base srv6-types:srv6-endpoint-type;
          }
          description "End behavior (End*) type";
        }
        leaf supported {
          type boolean;
          mandatory true;
          description "True if supported";
        }
       }
      }

     grouping srv6-support-headends {
       description "SRv6 Headend behavior support grouping";

       list headend-behavior {
         key "type";
         description "Headend behavior support";
         leaf type {
           type identityref {
             base srv6-types:srv6-headend-type;
           }
           description "Headend behavior (H*) type";
         }
        leaf supported {
          type boolean;
          mandatory true;
          description "True if supported";
        }
       }
     }

     grouping srv6-msd-signaled {
       description "SRv6 MSD signaled parameter support grouping";

      container msd {
        description "SRv6 signaled MSD parameter support";

        leaf max-sl {
          type uint8;
          description "Maximum value of the SL field in the SRH of
                       a received packet before applying the Endpoint behavior
                       associated with a SID";
        }
        leaf max-end-pop {
          type uint8;

Raza, et al.            Expires 5 September 2024               [Page 43]
Internet-Draft          YANG Data Model for SRv6              March 2024

          description "Maximum number of SIDs in the top SRH in an
                       SRH stack to which the router can apply
                       PSP or USP flavors";
        }
        leaf max-h_encap {
          type uint8;
          description "Maximum number of SIDs that can be pushed as
                       part of the H.Encaps* behavior";
        }
        leaf max-end_d {
          type uint8;
          description "Maximum number of SIDs in an SRH when applying
                       End.D* behaviors (e.g. End.X6 and End.DT6)";
        }
       }
     }

     grouping srv6-support-security-rules {
       description "SRv6 Security rules grouping";

      list security-rule {
        key "type";
        description "Security rule support";

        leaf type {
          type identityref {
            base srv6-types:srv6-security-type;
          }
          description "Security rule type";
        }
        leaf supported {
          type boolean;
          mandatory true;
          description "True if supported";
        }
       }
      }

     grouping srv6-support-counters {
       description "SRv6 Counters grouping";

      list counters {
        key "type";
        description "SRv6 counter support";

        leaf type {
          type identityref {
            base srv6-types:srv6-counter-type;

Raza, et al.            Expires 5 September 2024               [Page 44]
Internet-Draft          YANG Data Model for SRv6              March 2024

          }
          description "Counter type";
        }
        leaf supported {
          type boolean;
          mandatory true;
          description "True if supported";
        }
       }
      }

      grouping srv6-state-capabilities {
        description "SRv6 node capabilities grouping";
        container node-capabilities {
          config false;
          description "Node's SRv6 capabilities";

          uses srv6-support-ends;
          uses srv6-support-headends;
          uses srv6-msd-signaled;
          uses srv6-support-security-rules;
          uses srv6-support-counters;
        }
     }

      augment "/rt:routing/sr:segment-routing" {
         description
           "This augments Segment Routing (SR) with SRv6.";

      container srv6 {
       description "Segment Routing with IPv6 dataplane";

       /* config */
       leaf enable {
         type boolean;
         default false;
         description "Enable SRv6";
       }

       uses srv6-encap;
       uses srv6-locators;
       uses srv6-state-capabilities;
       uses srv6-state-sid;
      }
    }

    /* Notifications */

Raza, et al.            Expires 5 September 2024               [Page 45]
Internet-Draft          YANG Data Model for SRv6              March 2024

     grouping srv6-locator {
       description
         "An absolute reference to an SRv6 locator";
       leaf locator {
         type leafref {
           path "/rt:routing/sr:segment-routing/srv6:srv6/srv6:locators/srv6:locator/srv6:name";
         }
         description
           "Reference to a SRv6 locator.";
       }
     }

     notification srv6-locator-status-event {
       description
         "Notification event for a change of SRv6 locator operational
         status.";
       leaf operational-status {
         type srv6-types:srv6-status-type;
         description "Operational status";
       }
       uses srv6-locator;
     }

     notification srv6-sid-collision-event {
       description
         "Notification event for an SRv6 SID collision - i.e., attempt
         to bind an already bound SID to a new context";
       leaf sid {
         type srv6-types:srv6-sid;
         description "SRv6 SID";
       }
       container existing {
         description "Current assignment / bind";
         leaf end-behavior-type {
           type identityref {
             base srv6-types:srv6-endpoint-type;
           }
           description "End type";
         }
         // TODO: More
       }
       container requested {
         description "Requested assignment / bind";

         leaf end-behavior-type {
           type identityref {
             base srv6-types:srv6-endpoint-type;
           }

Raza, et al.            Expires 5 September 2024               [Page 46]
Internet-Draft          YANG Data Model for SRv6              March 2024

           description "End type";
         }
       }
     }
   } // module
   <CODE ENDS>

                       Figure 6: ietf-srv6-base.yang

5.3.  SRv6 Static

   This YANG module imports types defined in [RFC6991], [RFC8343], and
   [RFC8349].

   <CODE BEGINS> file "ietf-srv6-static@2022-01-14.yang"
   // RFC Editor: replace the above date with the date of
   // publication and remove this note.

   module ietf-srv6-static {
     yang-version 1.1;

     namespace "urn:ietf:params:xml:ns:yang:ietf-srv6-static";
     prefix srv6-static;

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

     import ietf-inet-types {
       prefix inet;
       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-segment-routing {
       prefix sr;
       reference "draft-ietf-spring-sr-yang";
     }

     import ietf-srv6-types {
       prefix srv6-types;

Raza, et al.            Expires 5 September 2024               [Page 47]
Internet-Draft          YANG Data Model for SRv6              March 2024

       reference "RFC XXXX: YANG Data Model for SRv6";
       // RFC Editor: replace XXXX with actual RFC number and remove
       // this note
     }

     import ietf-srv6-base {
       prefix srv6;
       reference "RFC XXXX: YANG Data Model for SRv6";
       // RFC Editor: replace XXXX with actual RFC number and remove
       // this note
     }

     organization
       "IETF SPRING Working Group";
     contact
       "WG Web:   <http://tools.ietf.org/wg/spring/>
        WG List:  <mailto:spring@ietf.org>

        Editor:   Kamran Raza
                  <mailto:skraza@cisco.com>

        Editor:   Jaganbabu Rajamanickam
                  <maito:jrajaman@cisco.com>

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

        Editor:   Zhibo Hu
                  <mailto:huzhibo@huawei.com>

        Editor:   Iftekhar Hussain
                  <mailto:IHussain@infinera.com>

        Editor:   Himanshu Shah
                  <mailto:hshah@ciena.com>

        Editor:   Daniel Voyer
                  <mailto:daniel.voyer@bell.ca>

        Editor:   Hani Elmalky
                  <mailto:helmalky@google.com>

        Editor:   Satoru Matsushima
                  <mailto:satoru.matsushima@gmail.com>

        Editor:   Katsuhiro Horiba
                  <mailto:katsuhiro.horiba@g.softbank.co.jp>

Raza, et al.            Expires 5 September 2024               [Page 48]
Internet-Draft          YANG Data Model for SRv6              March 2024

        Editor:   Ahmed AbdelSalam
                  <mailto:ahabdels@cisco.com>
        ";

     description
       "This YANG module defines the essential elements for the
        management of Static application for Segment-Routing with
        IPv6 dataplane (SRv6).

        Copyright (c) 2018 IETF Trust and the persons identified as
        authors of the code.  All rights reserved.

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

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

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

     revision 2024-03-04 {
       description
         "Fixed static yang warnings";
       reference
         "RFC XXXX: YANG Data Model for SRv6";
       // RFC Editor: replace XXXX with actual RFC number and remove
       // this note
     }

     revision 2022-01-14 {
       description
         "Alignment with SRv6 network programming rev16";
       reference
         "RFC XXXX: YANG Data Model for SRv6";
       // RFC Editor: replace XXXX with actual RFC number and remove
       // this note
     }

     revision 2019-10-30 {
       description
         "Extended model for EVPN behaviors";
       reference
         "RFC XXXX: YANG Data Model for SRv6";

Raza, et al.            Expires 5 September 2024               [Page 49]
Internet-Draft          YANG Data Model for SRv6              March 2024

       // RFC Editor: replace XXXX with actual RFC number and remove
       // this note
     }

     revision 2019-07-08 {
       description
         "Alignment with SRv6 network programming";
       reference
         "RFC XXXX: YANG Data Model for SRv6";
       // RFC Editor: replace XXXX with actual RFC number and remove
       // this note
     }

     revision 2018-10-22 {
       description
         "Initial revision.";
       reference
         "RFC XXXX: YANG Data Model for SRv6";
       // RFC Editor: replace XXXX with actual RFC number and remove
       // this note
     }

    /*
     * Config and State
     */

     grouping path-attrs-v6 {
        description
          "IPv6 Path properties";

        leaf interface {
           type if:interface-ref;
           description "The outgoing interface";
        }

        leaf next-hop {
          type inet:ipv6-address;
          description "The IP address of the next-hop";
        }

        leaf table {
          type srv6-types:table-id;
          description "The routing table associated with the next-hop";
        }

       uses srv6:path-attrs-cmn;
     }

Raza, et al.            Expires 5 September 2024               [Page 50]
Internet-Draft          YANG Data Model for SRv6              March 2024

     grouping path-attrs-v4 {
        description
          "IPv4 Path properties";

        leaf interface {
           type if:interface-ref;
           description "The outgoing interface";
        }

        leaf next-hop {
          type inet:ipv4-address;
          description "The IP address of the next-hop";
        }

        leaf table {
          type srv6-types:table-id;
          description "The routing table associated with the next-hop";
        }

       uses srv6:path-attrs-cmn;
     }

     grouping path-attrs-mpls {
        description
          "MPLS Path properties";

        leaf interface {
           type if:interface-ref;
           description "The outgoing interface";
        }

        leaf next-hop {
          type inet:ip-address;
          description "The IP address of the next-hop";
        }

       uses srv6:path-attrs-cmn;
     }

     grouping multi-paths-v6 {
       description "Multipath grouping";

       container paths {
         description "List of outgoing paths";
         list path {
           key path-index;
           description "The list of paths associated with the SID";

Raza, et al.            Expires 5 September 2024               [Page 51]
Internet-Draft          YANG Data Model for SRv6              March 2024

           leaf path-index {
             type uint8;
             description "Index of the path";
           }

           uses path-attrs-v6;
           container sid-list {
             description "SID-list associated with the path";
             uses srv6:path-out-sids;
           }
           }
         }
      }

     grouping multi-paths-v4 {
       description "Multipath grouping";

       container paths {
         description "List of outgoing paths";
         list path {
           key path-index;
           description "The list of paths associated with the SID";

           leaf path-index {
             type uint8;
             description "Index of the path";
           }

           uses path-attrs-v4;
           container sid-list {
             description "SID-list associated with the path";
             uses srv6:path-out-sids;
           }
          }
        }
      }

     grouping multi-paths-mpls {
       description "Multipath grouping";

       container paths {
         description "List of outgoing paths";
         list path {
           key path-index;
           description "The list of paths associated with the SID";

           leaf path-index {
             type uint8;

Raza, et al.            Expires 5 September 2024               [Page 52]
Internet-Draft          YANG Data Model for SRv6              March 2024

             description "Index of the path";
           }

           uses path-attrs-mpls;
           container sid-list {
             description "SID-list associated with the path";
             uses srv6:path-out-sids;
           }
          }
         }
      }

      grouping multi-paths-v6-BUM {
       description
         "Multipath grouping for EVPN bridging BUM use case";

       container paths {
         description
           "List of outgoing paths for flooding";
         list path {
           key path-index;
           description "The list of paths associated with the SID";

           leaf path-index {
             type uint8;
             description "Index of the path";
           }

           leaf l2-interface {
             type if:interface-ref;
             description "The outgoing L2 interface for flooding";
           }
         }
       }
     }

     grouping srv6-sid-config {
       description
         "Configuration parameters relating to SRv6 sid.";

       leaf function {
         type srv6-types:srv6-func-value;
         description
           "SRv6 function value.";
       }
       leaf end-behavior-type {
         type identityref {
           base srv6-types:srv6-endpoint-type;

Raza, et al.            Expires 5 September 2024               [Page 53]
Internet-Draft          YANG Data Model for SRv6              March 2024

         }
         mandatory true;
         description
           "Type of SRv6 end behavior.";
       }

       container end {
         when "../end-behavior-type = 'srv6-types:End'" {
           description
             "This container is valid only when the user chooses End
              behavior (variant: no PSP, no USP).";
         }
         description
           "The Endpoint function is the most basic function.
            FIB lookup on updated DA and forward accordingly
            to the matched entry.
            This is the SRv6 instantiation of a Prefix SID
            (variant: no PSP, no USP)";

       }

       container end_psp {
         when "../end-behavior-type = 'srv6-types:End_PSP'" {
           description
             "This container is valid only when the user chooses End
              behavior (variant: PSP only).";
         }
         description
           "The Endpoint function is the most basic function.
            FIB lookup on updated DA and forward accordingly
            to the matched entry.
            This is the SRv6 instantiation of a Prefix SID
            (variant: PSP only)";

       }

       container end_usp {
         when "../end-behavior-type = 'srv6-types:End_USP'" {
           description
             "This container is valid only when the user chooses End
              behavior (variant: USP only).";
         }
         description
           "The Endpoint function is the most basic function.
            FIB lookup on updated DA and forward accordingly
            to the matched entry.
            This is the SRv6 instantiation of a Prefix SID
            (variant: USP only)";

Raza, et al.            Expires 5 September 2024               [Page 54]
Internet-Draft          YANG Data Model for SRv6              March 2024

       }

       container end_psp_usp {
         when "../end-behavior-type = 'srv6-types:End_PSP_USP'" {
           description
             "This container is valid only when the user chooses End
              behavior (variant: PSP/USP).";
         }
         description
           "The Endpoint function is the most basic function.
            FIB lookup on updated DA and forward accordingly
            to the matched entry.
            This is the SRv6 instantiation of a Prefix SID
            (variant: PSP/USP)";

       }

       container end_usd {
         when "../end-behavior-type = 'srv6-types:End_USD'" {
           description
             "This container is valid only when the user chooses End
              behavior (variant: USD only).";
         }
         description
           "The Endpoint function is the most basic function.
            FIB lookup on updated DA and forward accordingly
            to the matched entry.
            This is the SRv6 instantiation of a Prefix SID
            (variant: USD)";
       }

       container end_psp_usd {
         when "../end-behavior-type = 'srv6-types:End_PSP_USD'" {
           description
             "This container is valid only when the user chooses End
              behavior (variant: PSP/USD).";
         }
         description
           "The Endpoint function is the most basic function.
            FIB lookup on updated DA and forward accordingly
            to the matched entry.
            This is the SRv6 instantiation of a Prefix SID
            (variant: PSP/USD)";

       }

       container end_usp_usd {
         when "../end-behavior-type = 'srv6-types:End_USP_USD'" {

Raza, et al.            Expires 5 September 2024               [Page 55]
Internet-Draft          YANG Data Model for SRv6              March 2024

           description
             "This container is valid only when the user chooses End
              behavior (variant: USP/USD).";
         }
         description
           "The Endpoint function is the most basic function.
            FIB lookup on updated DA and forward accordingly
            to the matched entry.
            This is the SRv6 instantiation of a Prefix SID
            (variant: USP/USD)";

       }

       container end_psp_usp_usd {
         when "../end-behavior-type = 'srv6-types:End_PSP_USP_USD'" {
           description
             "This container is valid only when the user chooses End
              behavior (variant: PSP/USP/USD).";
         }
         description
           "The Endpoint function is the most basic function.
            FIB lookup on updated DA and forward accordingly
            to the matched entry.
            This is the SRv6 instantiation of a Prefix SID
            (variant: PSP/USP/USD)";

       }

       container end-t {
         when "../end-behavior-type = 'srv6-types:End.T'" {
           description
             "This container is valid only when the user chooses
              End.T behavior (variant: no PSP, no USP).";
         }
         description
           "Endpoint with specific IPv6 table lookup (variant: no PSP,
           no USP).
            Lookup the next segment in IPv6 table T
            associated with the SID and forward via
            the matched table entry.
            The End.T is used for multi-table operation
            in the core.";

           // TODO presence "Mandatory child only if container is present";
           leaf lookup-table-ipv6 {
             type srv6-types:table-id;
             mandatory true;
             description

Raza, et al.            Expires 5 September 2024               [Page 56]
Internet-Draft          YANG Data Model for SRv6              March 2024

               "Table Id for lookup on updated DA (next segment)";
           }
       }

       container end-t_psp {
         when "../end-behavior-type = 'srv6-types:End.T_PSP'" {
           description
             "This container is valid only when the user chooses
              End.T behavior (variant: PSP only).";
         }
         description
           "Endpoint with specific IPv6 table lookup (variant: PSP only).
            Lookup the next segment in IPv6 table T
            associated with the SID and forward via
            the matched table entry.

            The End.T is used for multi-table operation
            in the core.";

           // TODO presence "Mandatory child only if container is present";

           leaf lookup-table-ipv6 {
             type srv6-types:table-id;
             mandatory true;
             description
               "Table Id for lookup on updated DA (next segment)";
           }
       }

       container end-t_usp {
         when "../end-behavior-type = 'srv6-types:End.T_USP'" {
           description
             "This container is valid only when the user chooses
              End.T behavior (variant: USP only).";
         }
         description
           "Endpoint with specific IPv6 table lookup (variant: USP only).
            Lookup the next segment in IPv6 table T
            associated with the SID and forward via
            the matched table entry.
            The End.T is used for multi-table operation
            in the core.";

           // TODO presence "Mandatory child only if container is present";

           leaf lookup-table-ipv6 {
             type srv6-types:table-id;
             mandatory true;

Raza, et al.            Expires 5 September 2024               [Page 57]
Internet-Draft          YANG Data Model for SRv6              March 2024

             description
               "Table Id for lookup on updated DA (next segment)";
           }
       }

       container end-t_psp_usp {
         when "../end-behavior-type = 'srv6-types:End.T_PSP_USP'" {
           description
             "This container is valid only when the user chooses
              End.T behavior (variant: USP/PSP).";
         }
         description
           "Endpoint with specific IPv6 table lookup (variant: USP/PSP).
            Lookup the next segment in IPv6 table T
            associated with the SID and forward via
            the matched table entry.
            The End.T is used for multi-table operation
            in the core.";

           // TODO presence "Mandatory child only if container is present";

           leaf lookup-table-ipv6 {
             type srv6-types:table-id;
             mandatory true;
             description
               "Table Id for lookup on updated DA (next segment)";
           }
       }

       container end-t_usd {
         when "../end-behavior-type = 'srv6-types:End.T_USD'" {
           description
             "This container is valid only when the user chooses
              End.T behavior (variant: USD only).";
         }
         description
           "Endpoint with specific IPv6 table lookup (variant: USD only).
            Lookup the next segment in IPv6 table T
            associated with the SID and forward via
            the matched table entry.
            The End.T is used for multi-table operation
            in the core.";

           // TODO presence "Mandatory child only if container is present";

           leaf lookup-table-ipv6 {
             type srv6-types:table-id;
             mandatory true;

Raza, et al.            Expires 5 September 2024               [Page 58]
Internet-Draft          YANG Data Model for SRv6              March 2024

             description
               "Table Id for lookup on updated DA (next segment)";
           }
       }

       container end-t_psp_usd {
         when "../end-behavior-type = 'srv6-types:End.T_PSP_USD'" {
           description
             "This container is valid only when the user chooses
              End.T behavior (variant: PSP/USD only).";
         }
         description
           "Endpoint with specific IPv6 table lookup (variant: PSP/USD
           only).
            Lookup the next segment in IPv6 table T
            associated with the SID and forward via
            the matched table entry.
            The End.T is used for multi-table operation
            in the core.";

           // TODO presence "Mandatory child only if container is present";

           leaf lookup-table-ipv6 {
             type srv6-types:table-id;
             mandatory true;
             description
               "Table Id for lookup on updated DA (next segment)";
           }
       }

       container end-t_usp_usd {
         when "../end-behavior-type = 'srv6-types:End.T_USP_USD'" {
           description
             "This container is valid only when the user chooses
              End.T behavior (variant: USP/USD only).";
         }
         description
           "Endpoint with specific IPv6 table lookup (variant:
           USP/USD only).
            Lookup the next segment in IPv6 table T
            associated with the SID and forward via
            the matched table entry.
            The End.T is used for multi-table operation
            in the core.";

           // TODO presence "Mandatory child only if container is present";

           leaf lookup-table-ipv6 {

Raza, et al.            Expires 5 September 2024               [Page 59]
Internet-Draft          YANG Data Model for SRv6              March 2024

             type srv6-types:table-id;
             mandatory true;
             description
               "Table Id for lookup on updated DA (next segment)";
           }
       }

       container end-t_psp_usp_usd {
         when "../end-behavior-type = 'srv6-types:End.T_PSP_USP_USD'" {
           description
             "This container is valid only when the user chooses
              End.T behavior (variant: USP only).";
         }
         description
           "Endpoint with specific IPv6 table lookup (variant:
           PSP/USP/USD only).
            Lookup the next segment in IPv6 table T
            associated with the SID and forward via
            the matched table entry.
            The End.T is used for multi-table operation
            in the core.";

           // TODO presence "Mandatory child only if container is present";

           leaf lookup-table-ipv6 {
             type srv6-types:table-id;
             mandatory true;
             description
               "Table Id for lookup on updated DA (next segment)";
           }
       }

      container end-x {
         when "../end-behavior-type = 'srv6-types:End.X'" {
           description
             "This container is valid only when the user chooses
              End.X behavior (variant: no USP/PSP)";
         }
         description
           "Endpoint with cross-connect to an array of
            layer-3 adjacencies (variant: no USP/PSP).
            Forward to layer-3 adjacency bound to the SID S.
            The End.X function is required to express any
            traffic-engineering policy.";

         leaf protected {
           type boolean;
           default false;

Raza, et al.            Expires 5 September 2024               [Page 60]
Internet-Draft          YANG Data Model for SRv6              March 2024

           description "Is Adj-SID protected?";
         }

         uses multi-paths-v6;
       }

      container end-x_psp {
         when "../end-behavior-type = 'srv6-types:End.X_PSP'" {
           description
             "This container is valid only when the user chooses
              End.X behavior (variant: PSP only)";
         }
         description
           "Endpoint with cross-connect to an array of
            layer-3 adjacencies (variant: PSP only).
            Forward to layer-3 adjacency bound to the SID S.
            The End.X function is required to express any
            traffic-engineering policy.";

         leaf protected {
           type boolean;
           default false;
           description "Is Adj-SID protected?";
         }

         uses multi-paths-v6;
       }

      container end-x_usp {
         when "../end-behavior-type = 'srv6-types:End.X_USP'" {
           description
             "This container is valid only when the user chooses
              End.X behavior (variant: USP only)";
         }
         description
           "Endpoint with cross-connect to an array of
            layer-3 adjacencies (variant: USP only).
            Forward to layer-3 adjacency bound to the SID S.
            The End.X function is required to express any
            traffic-engineering policy.";

         leaf protected {
           type boolean;
           default false;
           description "Is Adj-SID protected?";
         }

         uses multi-paths-v6;

Raza, et al.            Expires 5 September 2024               [Page 61]
Internet-Draft          YANG Data Model for SRv6              March 2024

       }

      container end-x_psp_usp {
         when "../end-behavior-type = 'srv6-types:End.X_PSP_USP'" {
           description
             "This container is valid only when the user chooses
              End.X behavior (variant: PSP/USP)";
         }
         description
           "Endpoint with cross-connect to an array of
            layer-3 adjacencies (variant: PSP/USP).
            Forward to layer-3 adjacency bound to the SID S.
            The End.X function is required to express any
            traffic-engineering policy.";

         leaf protected {
           type boolean;
           default false;
           description "Is Adj-SID protected?";
         }

         uses multi-paths-v6;
       }

      container end-x_usd {
         when "../end-behavior-type = 'srv6-types:End.X_USD'" {
           description
             "This container is valid only when the user chooses
              End.X behavior (variant: USD only)";
         }
         description
           "Endpoint with cross-connect to an array of
            layer-3 adjacencies (variant: PSP/USP).
            Forward to layer-3 adjacency bound to the SID S.
            The End.X function is required to express any
            traffic-engineering policy.";

         leaf protected {
           type boolean;
           default false;
           description "Is Adj-SID protected?";
         }

         uses multi-paths-v6;
       }

      container end-x_psp_usd {

Raza, et al.            Expires 5 September 2024               [Page 62]
Internet-Draft          YANG Data Model for SRv6              March 2024

         when "../end-behavior-type = 'srv6-types:End.X_PSP_USD'" {
           description
             "This container is valid only when the user chooses
              End.X behavior (variant: PSP/USD only)";
         }
         description
           "Endpoint with cross-connect to an array of
            layer-3 adjacencies (variant: PSP/USP).
            Forward to layer-3 adjacency bound to the SID S.
            The End.X function is required to express any
            traffic-engineering policy.";

         leaf protected {
           type boolean;
           default false;
           description "Is Adj-SID protected?";
         }

         uses multi-paths-v6;
       }

      container end-x_usp_usd {
         when "../end-behavior-type = 'srv6-types:End.X_USP_USD'" {
           description
             "This container is valid only when the user chooses
              End.X behavior (variant: USP/USD only)";
         }
         description
           "Endpoint with cross-connect to an array of
            layer-3 adjacencies (variant: PSP/USP).
            Forward to layer-3 adjacency bound to the SID S.
            The End.X function is required to express any
            traffic-engineering policy.";

         leaf protected {
           type boolean;
           default false;
           description "Is Adj-SID protected?";
         }

         uses multi-paths-v6;
       }

      container end-x_psp_usp_usd {
         when "../end-behavior-type = 'srv6-types:End.X_PSP_USP_USD'" {
           description
             "This container is valid only when the user chooses
              End.X behavior (variant: PSP/USP/USD only)";

Raza, et al.            Expires 5 September 2024               [Page 63]
Internet-Draft          YANG Data Model for SRv6              March 2024

         }
         description
           "Endpoint with cross-connect to an array of
            layer-3 adjacencies (variant: PSP/USP).
            Forward to layer-3 adjacency bound to the SID S.
            The End.X function is required to express any
            traffic-engineering policy.";

         leaf protected {
           type boolean;
           default false;
           description "Is Adj-SID protected?";
         }

         uses multi-paths-v6;
       }

       container end-b6-encaps {
         when "../end-behavior-type = 'srv6-types:End.B6.Encaps' or
               ../end-behavior-type = 'srv6-types:End.B6.Encaps.Red'" {
           description
             "This container is valid only when the user chooses
              End.B6.Encaps or End.B6.Encaps.Red behavior.";
         }
         description
            "Endpoint bound to an SRv6 Policy.
            Insert SRH based on the policy and forward the
            packet toward the first hop configured in the policy.
            This is the SRv6 instantiation of a Binding SID.
            This behavior also adds an outer IPv6 header";

         // TODO presence  "Mandatory child only if container is present";

         leaf policy-name {
           type string;
           mandatory true;
           description "SRv6 policy name.";
         }
         leaf source-address {
           type inet:ipv6-address;
           mandatory true;
           description
             "IPv6 source address for Encap.";
         }

         uses multi-paths-v6;
       }

Raza, et al.            Expires 5 September 2024               [Page 64]
Internet-Draft          YANG Data Model for SRv6              March 2024

       container end-bm {
         when "../end-behavior-type = 'srv6-types:End.BM'" {
           description
             "This container is valid only when the user chooses
              End.BM behavior.";
         }

         description
           "Endpoint bound to an SR-MPLS Policy.
            push an MPLS label stack <L1, L2, L3> on the
            received packet and forward the according to
            Lable L1.
            This is an SRv6 instantiation of an SR-MPLS Binding SID.";

         // TODO presence  "Mandatory child only if container is present";

         leaf policy-name {
           type string;
           mandatory true;
           description "SRv6 policy name";
         }
         uses multi-paths-mpls;
       }

       container end-dx6 {
         when "../end-behavior-type = 'srv6-types:End.DX6'" {
           description
             "This container is valid only when the user chooses
              End.DX6 behavior.";
         }
         description
           "Endpoint with decapsulation and cross-connect to
            an array of IPv6 adjacencies. Pop the (outer)
            IPv6 header and its extension headers and forward
            to layer-3 adjacency bound to the SID S.
            The End.DX6 used in the L3VPN use-case.";

         uses multi-paths-v6;
         // TODO: Backup path of type "Lookup in table"
       }

       container end-dx4 {
         when "../end-behavior-type = 'srv6-types:End.DX4'" {
           description
             "This container is valid only when the user chooses
              End.DX4 behavior.";
         }
         description

Raza, et al.            Expires 5 September 2024               [Page 65]
Internet-Draft          YANG Data Model for SRv6              March 2024

           "Endpoint with decapsulation and cross-connect to
            an array of IPv4 adjacencies.
            Pop the (outer) IPv6 header and its extension
            header and forward to layer-3 adjacency bound
            to the SID S.
            This would be equivalent to the per-CE VPN
            label in MPLS.";

         uses multi-paths-v4;
         // TODO: Backup path of type "Lookup in table"
       }
       container end-dt6 {
         when "../end-behavior-type = 'srv6-types:End.DT6'" {
           description
             "This container is valid only when the user chooses
              End.DT6 behavior.";
         }
         description
           "Endpoint with decapsulation and specific IPv6 table
            lookup.
            Pop the (outer) IPv6 header and its extension
            headers.
            Lookup the exposed inner IPv6 DA in IPv6
            table T and forward via the matched table entry.
            End.DT6 function is used in L3VPN use-case.";

         // TODO presence  "Mandatory child only if container is present";

         leaf lookup-table-ipv6 {
           type srv6-types:table-id;
           mandatory true;
           description "IPv6 table";
         }
       }
      container end-dt4 {
         when "../end-behavior-type = 'srv6-types:End.DT4'" {
           description
             "This container is valid only when the user chooses
              End.DT4 behavior.";
         }
         description
           "Endpoint with decapsulation and specific
            IPv4 table lookup.
            Pop the (outer) IPv6 header and its extension
            headers.
            Lookup the exposed inner IPv4 DA in IPv4
            table T and forward via the matched table entry.
            This would be equivalent to the per-VRF VPN label

Raza, et al.            Expires 5 September 2024               [Page 66]
Internet-Draft          YANG Data Model for SRv6              March 2024

            in MPLS.";

           // TODO presence "Mandatory child only if container is present";

         leaf lookup-table-ipv4 {
           type srv6-types:table-id;
           mandatory true;
           description "IPv4 table";
         }
       }
       container end-dt46 {
         when "../end-behavior-type = 'srv6-types:End.DT46'" {
           description
             "This container is valid only when the user chooses
              End.DT46 behavior.";
         }
         description
           "Endpoint with decapsulation and specific
            IP table lookup.
            Depending on the protocol type (IPv4 or IPv6)
            of the inner ip packet and the specific VRF name
            forward the packet.
            This would be equivalent to the per-VRF VPN
            label in MPLS.";

         // TODO presence  "Mandatory child only if container is present";

         leaf lookup-table-ipv4 {
           type srv6-types:table-id;
           mandatory true;
           description "IPv4 table";
         }
         leaf lookup-table-ipv6 {
           type srv6-types:table-id;
           mandatory true;
           description "IPv6 table";
         }
       }

       /* EVPN END behavior types */
       container end-dx2 {
         when "../end-behavior-type = 'srv6-types:End.DX2'" {
           description
             "This container is valid only when the user chooses
              End.DX2 behavior.";
         }
         description
           "This is an Endpoint with decapsulation and Layer-2

Raza, et al.            Expires 5 September 2024               [Page 67]
Internet-Draft          YANG Data Model for SRv6              March 2024

            cross-connect to OIF.
            Pop the (outer) IPv6 header and its extension headers.
            Forward the resulting frame via OIF associated to the SID.
            The End.DX2 function is the L2VPN/EVPN VPWS use-case.";

           container path {
             description "Outgoing path";
             leaf l2-interface {
               type if:interface-ref;
               mandatory true;
               description "Outgoing L2 interface";
             }
           }
       }

       container end-dx2v {
         when "../end-behavior-type = 'srv6-types:End.DX2V'" {
           description
             "This container is valid only when the user chooses
              End.DX2V behavior.";
         }
         description
           "Endpoint with decapsulation and specific VLAN
            L2 table lookup.
            Pop the (outer) IPv6 header and its extension headers.
            Lookup the exposed inner VLANs in L2 table T.
            Forward via the matched table entry.
            The End.DX2V is used for EVPN Flexible cross-connect
            use-cases";

         leaf lookup-table-vlan {
           type srv6-types:table-id;
           mandatory true;
           description
             "VLAN lookup table. There could be multiple
              vlan demux tables on the node, where a DX2V SID
              points to one vlan table";
         }
       }

       container end-dt2u {
         when "../end-behavior-type = 'srv6-types:End.DT2U'" {
           description
             "This container is valid only when the user chooses
              End.DT2U behavior.";
         }
         description
           "Endpoint with decapsulation and specific

Raza, et al.            Expires 5 September 2024               [Page 68]
Internet-Draft          YANG Data Model for SRv6              March 2024

            unicast L2 MAC table lookup.
            Pop the (outer) IPv6 header and its extension headers.
            Learn the exposed inner MAC SA in L2 MAC table T.
            Lookup the exposed inner MAC DA in L2 MAC table T.
            Forward via the matched T entry else to all L2OIF in T.
            The End.DT2U is used for EVPN Bridging unicast use cases";

         leaf lookup-table-mac {
           type srv6-types:table-id;
           mandatory true;
           description "MAC L2 lookup table";
         }
       }

       container end-dt2m {
         when "../end-behavior-type = 'srv6-types:End.DT2M'" {
           description
             "This container is valid only when the user chooses
              End.DT2M behavior.";
         }
         description
           "Endpoint with decapsulation and specific flooding table.
            Pop the (outer) IPv6 header and its extension headers.
            Learn the exposed inner MAC SA in L2 MAC table T.
            Forward on all L2OIF (in the flooding table) excluding the one
            identfied by Arg.FE2.
            The End.DT2M is used for EVPN Bridging BUM use case with
            ESI (Split Horizon) filtering capability.";

         leaf flooding-table {
           type srv6-types:table-id;
           mandatory true;
           description "L2 Flooding table (list of OIFs)";
         }

         uses multi-paths-v6-BUM;

         /* TODO - Support for argument Arg.FE2. It is an argument specific
            to EVPN ESI filtering and EVPN-ETREE used to exclude specific
            OIF (or set of OIFs) from flooding table. */
       }

       /* End of EVPN END behavior types */
     }

     grouping srv6-static-cfg {
       description
         "Grouping configuration and operation for SRv6 sid.";

Raza, et al.            Expires 5 September 2024               [Page 69]
Internet-Draft          YANG Data Model for SRv6              March 2024

         list sid {
           key "function";
           description "List of locally instantiated SIDs";

           uses srv6-sid-config;
         }
     }

    augment "/rt:routing/sr:segment-routing/srv6:srv6/srv6:locators/srv6:locator" {
        description
         "This augments locator leaf within SRv6.";

      container static {
       description "Static SRv6";

       /* Local SIDs */
       container local-sids {
         description
              "SRv6-static locally instantiated SIDs";

         uses srv6-static-cfg;
         /* no state for now; SID state accessible through base model */
      }

     }
    }
   } // module
   <CODE ENDS>

                      Figure 7: ietf-srv6-static.yang

6.  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 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.

Raza, et al.            Expires 5 September 2024               [Page 70]
Internet-Draft          YANG Data Model for SRv6              March 2024

   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.

   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.

   It goes without saying that this specification also inherits the
   security considerations captured in the SRv6 specification document
   [RFC8986].

7.  IANA Considerations

   This document requests the registration of the following URIs in the
   IETF "XML registry" [RFC3688]:

    +==============================================+============+=====+
    | URI                                          | Registrant | XML |
    +==============================================+============+=====+
    | urn:ietf:params:xml:ns:yang:ietf-srv6-types  | The IESG   | N/A |
    +----------------------------------------------+------------+-----+
    +----------------------------------------------+------------+-----+
    | urn:ietf:params:xml:ns:yang:ietf-srv6-base   | The IESG   | N/A |
    +----------------------------------------------+------------+-----+
    | urn:ietf:params:xml:ns:yang:ietf-srv6-static | The IESG   | N/A |
    +----------------------------------------------+------------+-----+

                                  Table 1

   This document requests the registration of the following YANG modules
   in the "YANG Module Names" registry [RFC6020]:

Raza, et al.            Expires 5 September 2024               [Page 71]
Internet-Draft          YANG Data Model for SRv6              March 2024

   +===========+=================================+===========+=========+
   |Name       |Namespace                        |Prefix     |Reference|
   +===========+=================================+===========+=========+
   |ietf-      |urn:ietf:params:xml:ns:yang:ietf-|srv6-types |This     |
   |srv6-types |srv6-types                       |           |document |
   +-----------+---------------------------------+-----------+---------+
   +-----------+---------------------------------+-----------+---------+
   |ietf-      |urn:ietf:params:xml:ns:yang:ietf-|srv6       |This     |
   |srv6-base  |srv6-base                        |           |document |
   +-----------+---------------------------------+-----------+---------+
   +-----------+---------------------------------+-----------+---------+
   |ietf-      |urn:ietf:params:xml:ns:yang:ietf-|srv6-static|This     |
   |srv6-static|srv6-static                      |           |document |
   +-----------+---------------------------------+-----------+---------+

                                  Table 2

   -- RFC Editor: Replace "This document" with the document RFC number
   at time of publication, and remove this note.

8.  Acknowledgments

   The authors would like to acknowledge Darren Dukes, Les Ginsberg,
   Ahmed Bashandy, Rajesh Venkateswaran, and Mike Mallin for their
   review of some of the contents in this draft.

9.  References

9.1.  Normative References

   [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>.

   [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>.

Raza, et al.            Expires 5 September 2024               [Page 72]
Internet-Draft          YANG Data Model for SRv6              March 2024

   [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>.

   [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>.

   [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>.

   [RFC8402]  Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L.,
              Decraene, B., Litkowski, S., and R. Shakir, "Segment
              Routing Architecture", RFC 8402, DOI 10.17487/RFC8402,
              July 2018, <https://www.rfc-editor.org/info/rfc8402>.

Raza, et al.            Expires 5 September 2024               [Page 73]
Internet-Draft          YANG Data Model for SRv6              March 2024

   [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>.

   [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>.

   [RFC8986]  Filsfils, C., Ed., Camarillo, P., Ed., Leddy, J., Voyer,
              D., Matsushima, S., and Z. Li, "Segment Routing over IPv6
              (SRv6) Network Programming", RFC 8986,
              DOI 10.17487/RFC8986, February 2021,
              <https://www.rfc-editor.org/info/rfc8986>.

   [RFC9020]  Litkowski, S., Qu, Y., Lindem, A., Sarkar, P., and J.
              Tantsura, "YANG Data Model for Segment Routing", RFC 9020,
              DOI 10.17487/RFC9020, May 2021,
              <https://www.rfc-editor.org/info/rfc9020>.

9.2.  Informative References

   [I-D.ietf-spring-sr-service-programming]
              Clad, F., Xu, X., Filsfils, C., Bernier, D., Li, C.,
              Decraene, B., Ma, S., Yadlapalli, C., Henderickx, W., and
              S. Salsano, "Service Programming with Segment Routing",
              Work in Progress, Internet-Draft, draft-ietf-spring-sr-
              service-programming-09, 20 February 2024,
              <https://datatracker.ietf.org/doc/html/draft-ietf-spring-
              sr-service-programming-09>.

   [RFC8754]  Filsfils, C., Ed., Dukes, D., Ed., Previdi, S., Leddy, J.,
              Matsushima, S., and D. Voyer, "IPv6 Segment Routing Header
              (SRH)", RFC 8754, DOI 10.17487/RFC8754, March 2020,
              <https://www.rfc-editor.org/info/rfc8754>.

   [RFC9433]  Matsushima, S., Ed., Filsfils, C., Kohno, M., Camarillo,
              P., Ed., and D. Voyer, "Segment Routing over IPv6 for the
              Mobile User Plane", RFC 9433, DOI 10.17487/RFC9433, July
              2023, <https://www.rfc-editor.org/info/rfc9433>.

Authors' Addresses

   Kamran Raza
   Cisco Systems
   Email: skraza@cisco.com

Raza, et al.            Expires 5 September 2024               [Page 74]
Internet-Draft          YANG Data Model for SRv6              March 2024

   Sonal Agarwal
   Cisco Systems
   Email: agarwaso@cisco.com

   Xufeng Liu
   Alef Edge
   Email: xufeng.liu.ietf@gmail.com

   Zhibo Hu
   Huawei Technologies
   Email: huzhibo@huawei.com

   Iftekhar Hussain
   Infinera Corporation
   Email: IHussain@infinera.com

   Himanshu Shah
   Ciena Corporation
   Email: hshah@ciena.com

   Daniel Voyer
   Bell Canada
   Email: daniel.voyer@bell.ca

   Hani Elmalky
   Individual
   Email: helmalky@google.com

   Satoru Matsushima
   SoftBank
   Email: satoru.matsushima@g.softbank.co.jp

   Katsuhiro Horiba
   SoftBank
   Email: katsuhiro.horiba@g.softbank.co.jp

   Jaganbabu Rajamanickam
   Cisco Systems
   Email: jrajaman@cisco.com

Raza, et al.            Expires 5 September 2024               [Page 75]
Internet-Draft          YANG Data Model for SRv6              March 2024

   Ahmed AbdelSalam
   Cisco Systems
   Email: ahabdels@cisco.com

Raza, et al.            Expires 5 September 2024               [Page 76]