SPRING Working Group                                             K. Raza
Internet-Draft                                           J. Rajamanickam
Intended status: Standards Track                           Cisco Systems
Expires: 15 November 2026
                                                           S. Matsushima
                                                                SoftBank
								
                                                                   P. Yu
                                                     Huawei Technologies
						     
                                                                  X. Liu
                                                              Individual
							      
                                                             14 May 2026


                     YANG Data Model for SRv6 Base
                  draft-ietf-spring-srv6-yang-base-02

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 models accordingly.

   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/.

   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 15 November 2026.

Copyright Notice

   Copyright (c) 2026 IETF Trust and the persons identified as the
   document authors.  All rights reserved.





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   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  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Specification of Requirements . . . . . . . . . . . . . . . .   3
   3.  SRv6 SID Building Blocks  . . . . . . . . . . . . . . . . . .   3
     3.1.  SID Structure . . . . . . . . . . . . . . . . . . . . . .   3
     3.2.  SID Compression . . . . . . . . . . . . . . . . . . . . .   4
     3.3.  SID Format  . . . . . . . . . . . . . . . . . . . . . . .   4
     3.4.  SID Allocation  . . . . . . . . . . . . . . . . . . . . .   4
       3.4.1.  Uncompressed  . . . . . . . . . . . . . . . . . . . .   4
       3.4.2.  Compressed (CSID) . . . . . . . . . . . . . . . . . .   5
   4.  YANG Model  . . . . . . . . . . . . . . . . . . . . . . . . .   7
     4.1.  Overview  . . . . . . . . . . . . . . . . . . . . . . . .   7
     4.2.  SRv6 Types  . . . . . . . . . . . . . . . . . . . . . . .   8
     4.3.  SRv6 Base . . . . . . . . . . . . . . . . . . . . . . . .   9
       4.3.1.  Configuration . . . . . . . . . . . . . . . . . . . .   9
       4.3.2.  State . . . . . . . . . . . . . . . . . . . . . . . .  12
       4.3.3.  Notification  . . . . . . . . . . . . . . . . . . . .  14
   5.  YANG Specification  . . . . . . . . . . . . . . . . . . . . .  15
     5.1.  SRv6 Types  . . . . . . . . . . . . . . . . . . . . . . .  15
     5.2.  SRv6 Base . . . . . . . . . . . . . . . . . . . . . . . .  49
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  71
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  71
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  72
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  72
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  75
   Appendix A.  Acknowledgments  . . . . . . . . . . . . . . . . . .  76
   Appendix B.  Contributors . . . . . . . . . . . . . . . . . . . .  76
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  77

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.





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   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 models (e.g. Static, ISIS, OSPFv3,
   BGP, EVPN, Service Chaining) may augment this model.

   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.  SRv6 SID Building Blocks

3.1.  SID Structure

   SRv6 network programming [RFC8986] defines SRv6 SID as consisting of
   LOC:FUNCT:ARG (Locator:Function:Argument), where a LOC may futher be
   represented as B:N (SID-block:Node-Identifier).  Thus, structure of
   an SRv6 SID is specified in terms of LBL (Locator Block Length), LNL
   (Locator Node Length), FL (Function Length), and AL (Argument
   Length).






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3.2.  SID Compression

   With respect to encoding SRv6 segment(s) in an IPv6 address (aka SID
   container), SRv6 SIDs can be categorized into following two main
   types:

   *  Uncompressed SID

   *  Compressed SID (CSID)

   In SRv6 [uncompressed] SID type, as defined in SRv6 network
   programming [RFC8986], a SID container (IPv6 address) contains only a
   single segment.  Whereas, in a compressed SID (CSID) type, a SID
   container may contain one or more segments.  The CSID types help
   reduce the size of SRv6 encapsulation, e.g. in the presence of long
   segment lists, and are defined in [RFC9800] with NEXT-CSID and
   REPLACE-CSID flavours.

3.3.  SID Format

   Within each of the above mentioned SID compression types, different
   variant of SID structures further categorize in the sub-types - e.g.
   NEXT-CSID with 32 bit block and 16 bit segment (LBL=32, LNL=16,
   FL=16), REPLACE-CSID with 32 bit block and 32 bit segment (LBL=32,
   LNL=32, FL=32).  In essence, a SID strucutre defines a specific
   format and hence we term it as a "SID Format".

   For ease of use, a SID format can be assigned an identity (e.g. name)
   and referenced using it - e.g. NEXT-CSID with LBL=32 LNL=16 FL=16 can
   be simply termed srv6-sid-fmt-cnext-3216.

3.4.  SID Allocation

   The following sections highlight some important manageability items
   with respect to SID allocation with SID format.

3.4.1.  Uncompressed

   The scope of the allocation space is Per-locator for an uncompressed
   SID type.  This means that an allocated FUNCT value (e.g. 0xF000) in
   a locator1 would be bound to an endpoint behavior different than the
   same FUNCT value allocated in a locator2.  In other words, a unique
   allocated SID is represented as LOC:FUNCT (i.e. B:N:FUNCT).

   The SID ID (allocation) space can be partitioned into Dynamic and
   Explicit allocation blocks.  Though the default order and the size of
   these blocks is an implementation choice, the YANG model should
   provide ability to change these parameters.



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3.4.2.  Compressed (CSID)

   The scope of the allocation space is Per-SIDBlock (instead of Per
   -Locator) for a compressed SID.  Assuming locator1 under SID block1
   and locator2 under SID block2, an allocated FUNCT value (e.g. 0xF000)
   in a locator1 (SID block1) would be bound to an endpoint behavior
   different than the same FUNCT value allocated under locator2 (SID
   block2).  However, if both locator1 and locator2 share the same SID
   block, then the allocated FUNCT value (and endpoint behavior bound to
   it) is also shared across locators.  In other words, a unique
   allocated SID is represented as B:FUNCT where B is the SID Block.

   The compressed SID architecure paritions the SID allocation space
   into two:

   *  Global ID Block (GIB): The GIB space is shared among all SR
      segment endpoint nodes and is used for allocations of global
      segments (such as SIDs that identify a node).

   *  Local ID Block (LIB): The LIB space is unique per node and is used
      for allocations of local segments (such as SIDs that identify
      adjacency, services, etc. at the node).  Since this is not a
      shared space, a node can fully utilize the entire LIB space
      without consideration of assignments at other nodes.

   In SID allocation space, the LIB space follows the GIB space.  The
   following figure shows CSID allocation space and IDs:



                       +------------------------------+
             id 0      |                              | Gs
               . . .   |                              |
               . . .   |            GIB               |
               . . .   |                              |
               . . .   |                              | Ge
                       +------------------------------+
               . . .   |                              | Ls
               . . .   |            LIB               |
               . . .   |                              |
             id N      |                              | Le
                       +------------------------------+


                        Figure 1: CSID GIB/LIB Space






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   In the above figure, the Gs and Ge refer to "GIB start" and "GIB end"
   indexes, whereas the Ls and Le refer to "LIB start" and "LIB end"
   indexes.  For 16 bit CSID, Id range is 0x0000-0xffff, where Gs and Le
   are fixed at Id 0x0000 and 0xffff respectively.

   The implementations may decide default sizes for their GIB and LIB
   partitions.  However, the YANG model should provide ability to change
   the partition size of the LIB in order to shrink or expand it, thus
   conversely expanding or shrinking GIB paritition.

   It is advisable to reserve a block of Ids at the bottom of CSID LIB
   space for advanced use cases for future use.  We can term it as RLIB
   (Reserved LIB) partition.  The implementations may decide default
   size for RLIB partition.  The YANG mode should provide ability to
   change the partition size of the RLIB in order to shrink or expand
   it.

   The remaining (non-reserved) LIB space should also be partitioned
   into Dynamic and Explicit CSID allocation blocks.  The order of the
   blocks is left upto the implementations - i.e. Dynamic block followed
   by Explicit block, or vice versa.  The implementations may also
   decide default sizes for their Dynamic LIB and Explicit LIB blocks.
   However, the YANG model should provide ability to change the block
   size of the explicit LIB (in order to shrink or expand it), and as
   well as the start of the explicit LIB block.

   The following figure further expands the Figure 1 to illustrate LIB
   space partitions.























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                       .                              .
                       | . . . . . . GIB . . . . . .  |
                       |                              |
                       +------------------------------+
                 ^  Ls |                              | LDs
                 |     |                              |
                 |     |        Dynamic LIB           |
                 |     |                              |
                 |     |                              |
                 |     |                              |
                 |     |                              | LDe
                 |     +------------------------------+
                       |                              | LEs
                LIB    |                              |
                       |        Explicit LIB          |
                 |     |                              |
                 |     |                              | LEe
                 |     +------------------------------+
                 |     |                              | LRs
                 |     |         Reserved LIB         |
                 |  Le |                              | LRe
                 v     +------------------------------+


                    Figure 2: CSID LIB Space parititions

   In the above figure, the LDs and LDe refer to "Dynamic LIB start" and
   "Dynamic LIB end" indexes, the LEs and LEe refer to "Explicit LIB
   start" and "Explicit LIB end" indexes, and the LRs and LRe refer to
   "Reserved LIB start" and "Reserved LIB end" indexes.  It goes without
   saying that LDs is same as Ls and LRe is same as Le.

   In the above Figure, Explicit partition follows Dynamic partition.  A
   similar illustration and explanation can be laid out where Dynamic
   partition follows Explicit partition.

4.  YANG Model

4.1.  Overview

   This document defines following two 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.)





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   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].

4.2.  SRv6 Types

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

   *  Locator:

      -  srv6-locator-name-type: SRv6 locator name

      -  srv6-locator-len: SRv6 locator prefix length

      -  srv6-locator-block-len: Block length in a SRv6 locator prefix

      -  srv6-locator-node-len: Node-id field length in an SRv6 locator
         prefix

   *  SID:

      -  srv6-sid: SRv6 SID

      -  srv6-sid-func-len: FUNCT field length of an SRv6 SID

      -  srv6-sid-arg-len: ARG field length of an SRv6 SID

      -  srv6-sid-func-value: Typedef for FUNCT value of an SRv6 SID

      -  srv6-sid-func-value-reserved-type: Enum (list) of "reserved"
         FUNCT opcode

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

      -  srv6-sid-structure: Grouping that defines structure of an SRv6
         SID in terms of LBL (Locator Block Length), LNL (Locator Node
         Length), FL (Function Length), and AL (Argument Length).
         Please refer Section 3.1.



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      -  srv6-sid-compression-type: Enum that lists compression types
         for an SRv6 SID as uncompressed, compressed-next, and
         compressed-replace.  Please refer Section 3.2.

      -  srv6-sid-format-types: Identifies well known SID formats from
         each compression type.  Please refer Section 3.3

   *  Other:

      -  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.

4.3.  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.

4.3.1.  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 H.Encaps* operation.

   *  SID Formats: Configures SID format specific parameters - e.g.
      provide configuration option to change GIB/LIB split for NEXT-CSID
      formats.  The Section 3.4 describes SID format's specific
      parameters in more details.







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   *  Locator(s) Specification: SRv6 locator is a fundamental construct
      for an SRv6 network.  This is the base manageability construct for
      SID allocation (see Section 3.4) on the local box, and also
      advertised as IPV6 prefix for node reachability.  The key
      attributes of a locator are:

      -  Name: This is an identifier for a locator.

      -  SID format: The SID format associated with the locator that
         dictates both the locator prefix and the SIDs allocated from
         the locator.

      -  Prefix: Specifies locator's IPv6 prefix for node reachability
         and SID allocation, either off the locator (for uncompressed
         SIDs) or off the locator block (for CSIDs).

      -  Algorithm: A locator can be associated to an IGP algorithm for
         FlexAlgo use.  By default, locator's algorithm is default
         algorithm (0).

      -  Anycast: Specifies locator as an anycast locator, allowing
         anycast operations in IGP

      -  Auto-allocation of Node SID: As locator becomes operational, a
         Node SID can be automatically allocated with default variant
         (e.g. End_PSP_USD).  This configuration allows either to
         disable the auto-allocation, or to change the default variant.

   *  SIDs: SRv6 SIDs related configuration parameters:

      -  sid-holdtime: The holdtime before releasing a previously
         allocated SID to free pool

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
















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 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 sid-formats
        |  +--rw format* [type]
        |     +--rw type                identityref
        |     +--rw uncompressed-16
        |     |  +--rw id-block
        |     |     +--rw explicit
        |     |        +--rw start?   uint16
        |     |        +--rw size?    uint16
        |     +--rw csid-next-16
        |        +--rw local-id-block
        |           +--rw start?      uint16
        |           +--rw explicit
        |              +--rw start?   uint16
        |              +--rw size?    uint16
        +--rw locators
        |  +--rw locator* [name]
        |     +--rw name               srv6-types:srv6-locator-name-type
        |     +--rw enable?            boolean
        |     +--rw format             identityref
        |     +--rw prefix
        |     |  +--rw address    inet:ipv6-address
        |     |  +--rw length     srv6-types:srv6-locator-len
        |     +--rw algorithm?                  uint8
        |     +--rw anycast?                    boolean
        |     +--rw node-sid-auto-allocation
        |        +--rw behavior?   identityref
        |        +--rw disable?    boolean
        +--rw sids
           +--rw sid-holdtime?   uint8


                   Figure 3: SRv6 Base - Config Tree






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4.3.2.  State

   As per NMDA model, the state related to configuration items specified
   in above section Section 4.3.1 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 SRv6 MSD [RFC9702] that need to
      be signaled in an SRv6 network by the protocols.

   *  SID Formats: provides information related to supported SID
      formats.  The information includes format's description,
      compression type, and SID structure.

   *  Locators: provides information related to local and remote
      locators.  The local locators information includes locator
      operational state, and state of address conflict with any ipv6
      address configured on local interfaces etc.  The remote locators
      information includes traffic accounting for a remote locator
      prefix.

   *  sid: provides information related to locally allocated and
      instantiated SIDs on the node.  This includes two types of
      information:

      1.  aggregate across all SIDs such as aggregate counts and summary

      2.  per SID information such as SID value, behavior, associated
          locator, 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
       +--ro node-capabilities
       |  +--ro end-behavior* [type]
       |  |  +--ro type         identityref
       |  |  +--ro supported    boolean



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       |  +--ro headend-behavior* [type]
       |  |  +--ro type         identityref
       |  |  +--ro supported    boolean
       |  +--ro msd
       |  |  +--ro msds* [msd-type]
       |  |     +--ro msd-type     identityref
       |  |     +--ro msd-value?   uint8
       |  +--ro security-rule* [type]
       |  |  +--ro type         identityref
       |  |  +--ro supported    boolean
       |  +--ro counters* [type]
       |     +--ro type         identityref
       |     +--ro supported    boolean
       +--rw sid-formats
       |  +--rw format* [type]
       |     +--rw type                identityref
       |     +--ro compression-type?
                                    srv6-types:srv6-sid-compression-type
       |     +--ro description?        string
       |     +--ro sid-structure
       |        +--ro locator-block-length?
                                       srv6-types:srv6-locator-block-len
       |        +--ro locator-node-length?
                                        srv6-types:srv6-locator-node-len
       |        +--ro function-length?  srv6-types:srv6-sid-func-len
       |        +--ro argument-length?  srv6-types:srv6-sid-arg-len
       +--rw locators
       |  +--rw locator* [name]
       |  |  +--rw name                srv6-types:srv6-locator-name-type
       |  |  +--ro operational-status?  srv6-types:srv6-status-type
       |  |  +--ro is-in-address-conflict?     boolean
       |  +--ro remote* [prefix]
       |     +--ro prefix                inet:ipv6-prefix
       |     +--ro traffic-accounting
       |        +--ro inbound
       |        |  +--ro in-pkts?     yang:counter64
       |        |  +--ro in-octets?   yang:counter64
       |        +--ro outbound
       |           +--ro paths* [interface next-hop]
       |              +--ro interface     if:interface-ref
       |              +--ro next-hop      inet:ipv6-address
       |              +--ro out-pkts?     yang:counter64
       |              +--ro out-octets?   yang:counter64
       +--rw sids
          +--ro counts
          |  +--ro allocated?   uint32
          |  +--ro stale?       uint32
          +--ro sid* [sid]



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             +--ro sid           srv6-types:srv6-sid
             +--ro behavior?     identityref
             +--ro locator?      -> /rt:routing/sr:segment-routing/
                                        srv6:srv6/locators/locator/name
             +--ro allocation
             |  +--ro alloc-type?              srv6-types:sid-alloc-type
             |  +--ro owner* [type instance]
             |  |  +--ro type         identityref
             |  |  +--ro instance     string
             |  |  +--ro is-winner?   boolean
             |  +--ro allocated-from-reserved?   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 lookup-table-id?   uint32
             |        +--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 lookup-table-id?     uint32
             |        +--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 success
                   +--ro in-pkts?     yang:counter64
                   +--ro in-octets?   yang:counter64


                   Figure 4: SRv6 Base - State Tree

4.3.3.  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:




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   *  locator operational state changes

   *  SID (allocation) collision event

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

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 owner* [type instance]
       |     +--ro type        identityref
       |     +--ro instance    string
       +--ro requested
          +--ro end-behavior-type?   identityref
          +--ro requester
             +--ro type?       identityref
             +--ro instance?   string


               Figure 5: SRv6 Base - Notification Tree

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 [RFC8754],
   [RFC8986], [RFC9433], [RFC9491], [RFC9524], [RFC9800], [RFC9801],
   [I-D.ietf-spring-srv6-mpls-interworking],
   [I-D.ietf-rtgwg-srv6-egress-protection],
   [I-D.ietf-bess-mvpn-evpn-sr-p2mp],
   [I-D.ietf-spring-srv6-path-segment], and
   [I-D.ietf-spring-sr-service-programming].





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   <CODE BEGINS> file "ietf-srv6-types@2026-05-06.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;

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

        Editor:   Pingping Yu
                  <mailto:susana.yu@huawei.com>

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

     description
       "This YANG module defines the essential types for the
        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



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        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 2026-05-06 {
       description
         "Add missing behaviors in the srv6-endpoint-type identity and
          srv6-headend-type identity";
       reference
         "RFC XXXX: YANG Data Model for SRv6 types";
       // RFC Editor: replace XXXX with actual RFC number and remove
       // this note
     }

     revision 2025-07-07 {
       description
         "Adding compressed SID and few other missing def";
       reference
         "RFC XXXX: YANG Data Model for SRv6";
       // RFC Editor: replace XXXX with actual RFC number and remove
       // this note
     }

     revision 2024-11-21 {
       description
         "Added SID structure definition and ";
       reference
         "RFC XXXX: YANG Data Model for SRv6";
        // 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



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         "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";
       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



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         "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";
     }

     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



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         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
         (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";



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     }

     identity End.B6.Encaps {
       base srv6-endpoint-type;
       description
         "Endpoint bound to an SRv6 Policy, where SIDlist is encoded
          using the Encap mode (new IPv6 header)";
       reference
         "RFC 8986";
     }

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

     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



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         "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 {
       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



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         "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).";
       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).";



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       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;
       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";
     }



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     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).";
       reference
         "RFC 8986";
     }

     identity End.MAP {
       base srv6-endpoint-type;
       description
         "DMM End.MAP";
       reference
         "RFC9433";
     }

     identity End.Limit {
       base srv6-endpoint-type;
       description
         "DMM End.Limit";
       reference
         "RFC9433";
     }

     /* Endpoints defined under RFC9800 */

     identity END.NEXT-CSID {
       base srv6-endpoint-type;
       description
         "End SID with the NEXT-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.NEXT-CSID_PSP {
       base srv6-endpoint-type;
       description
         "End SID with the NEXT-CSID PSP flavor";
       reference



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         "RFC 9800";
     }

     identity END.NEXT-CSID_USP {
       base srv6-endpoint-type;
       description
         "End SID with the NEXT-CSID USP flavor";
       reference
         "RFC 9800";
     }

     identity END.NEXT-CSID_PSP_USP {
       base srv6-endpoint-type;
       description
         "End SID with the NEXT-CSID PSP/USP flavor";
       reference
         "RFC 9800";
     }

     identity END.NEXT-CSID_USD {
       base srv6-endpoint-type;
       description
         "End SID with the NEXT-CSID USD flavor";
       reference
         "RFC 9800";
     }

     identity END.NEXT-CSID_PSP_USD {
       base srv6-endpoint-type;
       description
         "End SID with the NEXT-CSID PSP/USD flavor";
       reference
         "RFC 9800";
     }

     identity END.NEXT-CSID_USP_USD {
       base srv6-endpoint-type;
       description
         "End SID with the NEXT-CSID USP/USD flavor";
       reference
         "RFC 9800";
     }

     identity END.NEXT-CSID_PSP_USP_USD {
       base srv6-endpoint-type;
       description
         "End SID with the NEXT-CSID PSP/USP/USD flavor";
       reference



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         "RFC 9800";
     }

     identity END.X.NEXT-CSID {
       base srv6-endpoint-type;
       description
         "End.X SID with the NEXT-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.X.NEXT-CSID_PSP {
       base srv6-endpoint-type;
       description
         "End.X SID with the NEXT-CSID PSP flavor";
       reference
         "RFC 9800";
    }

     identity END.X.NEXT-CSID_USP {
       base srv6-endpoint-type;
       description
         "End.X SID with the NEXT-CSID USP flavor";
       reference
         "RFC 9800";
     }

     identity END.X.NEXT-CSID_PSP_USP {
       base srv6-endpoint-type;
       description
         "End.X SID with the NEXT-CSID PSP/USP flavor";
       reference
         "RFC 9800";
     }

     identity END.X.NEXT-CSID_USD {
       base srv6-endpoint-type;
       description
         "End.X SID with the NEXT-CSID USD flavor";
       reference
         "RFC 9800";
     }

     identity END.X.NEXT-CSID_PSP_USD {
       base srv6-endpoint-type;
       description
         "End.X SID with the NEXT-CSID PSP/USD flavor";
       reference



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         "RFC 9800";
     }

     identity END.X.NEXT-CSID_USP_USD {
       base srv6-endpoint-type;
       description
         "End.X SID with the NEXT-CSID USP/USD flavor";
       reference
         "RFC 9800";
     }

     identity END.X.NEXT-CSID_PSP_USP_USD {
       base srv6-endpoint-type;
       description
         "End.X SID with the NEXT-CSID PSP/USP/USD flavor";
       reference
         "RFC 9800";
     }

     identity End.DX6.NEXT-CSID {
       base srv6-endpoint-type;
       description
         "NEXT-CSID Endpoint with decapsulation and cross-connect
         to an array of IPv6 adjacencies - uDX6";
       reference
         "RFC 9800";
     }

     identity End.DX4.NEXT-CSID {
       base srv6-endpoint-type;
       description
         "NEXT-CSID Endpoint with decapsulation and cross-connect
         to an array of IPv4 adjacencies - uDX4";
       reference
         "RFC 9800";
     }

     identity End.DT6.NEXT-CSID {
       base srv6-endpoint-type;
       description
         "NEXT-CSID Endpoint with decapsulation and specific
         IPv6 table lookup - uDT6";
       reference
         "RFC 9800";
     }

     identity End.DT4.NEXT-CSID {
       base srv6-endpoint-type;



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       description
         "NEXT-CSID Endpoint with decapsulation and specific
         IPv4 table lookup - uDT4";
       reference
         "RFC 9800";
     }

     identity End.DT46.NEXT-CSID {
       base srv6-endpoint-type;
       description
         "NEXT-CSID Endpoint with decapsulation and specific IP
         (IPv4 or IPv6) table lookup - uDT46";
       reference
         "RFC 9800";
     }

     identity End.DX2.NEXT-CSID {
       base srv6-endpoint-type;
       description
         "NEXT-CSID Endpoint with decapsulation and Layer-2
         cross-connect to an L2 interface - uDX2";
       reference
         "RFC 9800";
     }

     identity End.DX2V.NEXT-CSID {
       base srv6-endpoint-type;
       description
         "NEXT-CSID Endpoint with decapsulation and specific
         VLAN L2 table lookup - uDX2V";
       reference
         "RFC 9800";
     }

     identity End.DT2U.NEXT-CSID {
       base srv6-endpoint-type;
       description
         "NEXT-CSID Endpoint with decapsulation and specific
         unicast MAC L2 table lookup - uDT2U";
       reference
         "RFC 9800";
     }

     identity End.DT2M.NEXT-CSID {
       base srv6-endpoint-type;
       description
         "NEXT-CSID Endpoint with decapsulation and specific L2 table
         flooding - uDT2M";



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       reference
         "RFC 9800";
     }

     /* DMM - RFC9433 */

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

     identity End.M.GTP6.Di {
       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 End.DTM {
       base srv6-endpoint-type;
       description
         "Endpoint with decapsulation and lookup in MPLS table";
       reference
         "draft-ietf-spring-srv6-mpls-interworking-02";
     }

     identity End.M {



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       base srv6-endpoint-type;
       description
         "Endpoint behavior to steer traffic to a protector egress
      upon failure of the primary egress";
       reference
         "draft-ietf-rtgwg-srv6-egress-protection-23";
     }

     identity End.Replicate {
       base srv6-endpoint-type;
       description
         "Endpoint with replication and/or decapsulate";
       reference
         "RFC 9524";
     }

     identity End.DTMC4 {
       base srv6-endpoint-type;
       description
         "Endpoint with Decapsulation and IPv4 Multicast Table Lookup";
       reference
         "draft-ietf-bess-mvpn-evpn-sr-p2mp-18";
     }

     identity End.DTMC6 {
       base srv6-endpoint-type;
       description
         "Endpoint with Decapsulation and IPv6 Multicast Table Lookup";
       reference
         "draft-ietf-bess-mvpn-evpn-sr-p2mp-18";
     }

     identity End.DTMC46 {
       base srv6-endpoint-type;
       description
         "Endpoint with Decapsulation and IP Multicast Table Lookup";
       reference
         "draft-ietf-bess-mvpn-evpn-sr-p2mp-18";
     }

     identity End.NSH {
       base srv6-endpoint-type;
       description
         "Endpoint behavior for NSH processing";
       reference
         "RFC 9491";
     }




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     identity End.T.NEXT-CSID {
       base srv6-endpoint-type;
       description
         "End.T SID with the NEXT-CSID flavor.";
       reference
         "RFC 9800";
     }

     identity End.T.NEXT-CSID_PSP {
       base srv6-endpoint-type;
       description
         "End.T PSP SID with the NEXT-CSID flavor.";
       reference
         "RFC 9800";
     }

     identity End.T.NEXT-CSID_USP {
       base srv6-endpoint-type;
       description
         "End.T USP SID with the NEXT-CSID flavor.";
       reference
         "RFC 9800";
     }

     identity End.T.NEXT-CSID_PSP_USP {
       base srv6-endpoint-type;
       description
         "End.T PSP_USP SID with the NEXT-CSID flavor.";
       reference
         "RFC 9800";
     }

     identity End.T.NEXT-CSID_USD {
       base srv6-endpoint-type;
       description
         "End.T USD SID with the NEXT-CSID flavor.";
       reference
         "RFC 9800";
     }

     identity End.T.NEXT-CSID_PSP_USD {
       base srv6-endpoint-type;
       description
         "End.T PSP_USD SID with the NEXT-CSID flavor.";
       reference
         "RFC 9800";
     }




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     identity End.T.NEXT-CSID_USP_USD {
       base srv6-endpoint-type;
       description
         "End.T USP_USD SID with the NEXT-CSID flavor.";
       reference
         "RFC 9800";
     }

     identity End.T.NEXT-CSID_PSP_USP_USD {
       base srv6-endpoint-type;
       description
         "End.T PSP_USP_USD SID with the NEXT-CSID flavor.";
       reference
         "RFC 9800";
     }

     identity END.B6.Encaps.NEXT-CSID {
       base srv6-endpoint-type;
       description
         "End.B6.Encaps SID with the NEXT-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.B6.Encaps.Red.NEXT-CSID {
       base srv6-endpoint-type;
       description
         "End.B6.Encaps.Red SID with the NEXT-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.BM.NEXT-CSID {
       base srv6-endpoint-type;
       description
         "End.BM SID with the NEXT-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.LBS.NEXT-CSID {
       base srv6-endpoint-type;
       description
         "End behavior variant to modify the locator-block of the active CSID sequence in NEXT-CSID";
       reference
         "RFC 9800";
     }




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     identity END.XLBS.NEXT-CSID {
       base srv6-endpoint-type;
       description
         "End.X behavior variant to modify the locator-block of the active CSID sequence in NEXT-CSID";
       reference
         "RFC 9800";
     }

     identity END.B6.Encaps.Red.NEXT-CSID_PSP_USD {
       base srv6-endpoint-type;
       description
         "End.B6.Encaps.Red PSP_USD SID variant with the NEXT-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.PSID {
       base srv6-endpoint-type;
       description
         "Endpoint behavior associated with SRv6 path segment";
       reference
         "draft-ietf-spring-srv6-path-segment-02";
     }

     identity END.REPLACE-SID {
       base srv6-endpoint-type;
       description
         "End SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.REPLACE-SID_PSP {
       base srv6-endpoint-type;
       description
         "End SID with the REPLACE-CSID PSP flavor";
       reference
         "RFC 9800";
     }

     identity END.REPLACE-SID_USP {
       base srv6-endpoint-type;
       description
         "End SID with the REPLACE-CSID USP flavor";
       reference
         "RFC 9800";
     }




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     identity END.REPLACE-SID_PSP_USP {
       base srv6-endpoint-type;
       description
         "End SID with the REPLACE-CSID PSP/USP flavor";
       reference
         "RFC 9800";
     }

     identity END.X.REPLACE-CSID {
       base srv6-endpoint-type;
       description
         "End.X SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.X.REPLACE-CSID_PSP {
       base srv6-endpoint-type;
       description
         "End.X SID with the REPLACE-CSID PSP flavor";
       reference
         "RFC 9800";
     }

     identity END.X.REPLACE-CSID_USP {
       base srv6-endpoint-type;
       description
         "End.X SID with the REPLACE-CSID USP flavor";
       reference
         "RFC 9800";
     }

     identity END.X.REPLACE-CSID_PSP_USP {
       base srv6-endpoint-type;
       description
         "End.X SID with the REPLACE-CSID PSP/USP flavor";
       reference
         "RFC 9800";
     }


    identity END.T.REPLACE-CSID {
       base srv6-endpoint-type;
       description
         "End.T SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }



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     identity END.T.REPLACE-CSID_PSP {
       base srv6-endpoint-type;
       description
         "End.T PSP SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.T.REPLACE-CSID_USP {
       base srv6-endpoint-type;
       description
         "End.T USP SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.T.REPLACE-CSID_PSP_USP {
       base srv6-endpoint-type;
       description
         "End.T PSP/USP SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.B6.Encaps.REPLACE-CSID {
       base srv6-endpoint-type;
       description
         "End.B6.Encaps SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.BM.REPLACE-CSID {
       base srv6-endpoint-type;
       description
         "End.BM.Red SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.DX6.REPLACE-CSID {
       base srv6-endpoint-type;
       description
         "End.DX6 SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }




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     identity END.DX4.REPLACE-CSID {
       base srv6-endpoint-type;
       description
         "End.DX4 SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.DT6.REPLACE-CSID {
       base srv6-endpoint-type;
       description
         "End.DT6 SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.DT4.REPLACE-CSID {
       base srv6-endpoint-type;
       description
         "End.DT4 SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.DT46.REPLACE-CSID {
       base srv6-endpoint-type;
       description
         "End.DT46 SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.DX2.REPLACE-CSID {
       base srv6-endpoint-type;
       description
         "End.DX2 SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.DX2V.REPLACE-CSID {
       base srv6-endpoint-type;
       description
         "End.DX2V SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }




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     identity END.DT2U.REPLACE-CSID {
       base srv6-endpoint-type;
       description
         "End.DT2U SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.DT2M.REPLACE-CSID {
       base srv6-endpoint-type;
       description
         "End.DT2M SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.B6.Encaps.Red.REPLACE-CSID {
       base srv6-endpoint-type;
       description
         "End.B6.Encaps.Red SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.REPLACE-SID_USD {
       base srv6-endpoint-type;
       description
         "End SID with the REPLACE-CSID USD flavor";
       reference
         "RFC 9800";
     }

     identity END.REPLACE-SID_PSP_USD {
       base srv6-endpoint-type;
       description
         "End SID with the REPLACE-CSID PSP/USD flavor";
       reference
         "RFC 9800";
     }

     identity END.REPLACE-SID_USP_USD {
       base srv6-endpoint-type;
       description
         "End SID with the REPLACE-CSID USP/USD flavor";
       reference
         "RFC 9800";
     }




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     identity END.REPLACE-SID_PSP_USP_USD {
       base srv6-endpoint-type;
       description
         "End SID with the REPLACE-CSID PSP/USP/USD flavor";
       reference
         "RFC 9800";
     }

     identity END.X.REPLACE-CSID_USD {
       base srv6-endpoint-type;
       description
         "End.X SID with the REPLACE-CSID USD flavor";
       reference
         "RFC 9800";
     }

     identity END.X.REPLACE-CSID_PSP_USD {
       base srv6-endpoint-type;
       description
         "End.X SID with the REPLACE-CSID PSP/USD flavor";
       reference
         "RFC 9800";
     }

     identity END.X.REPLACE-CSID_USP_USD {
       base srv6-endpoint-type;
       description
         "End.X SID with the REPLACE-CSID USP/USD flavor";
       reference
         "RFC 9800";
     }

     identity END.X.REPLACE-CSID_PSP_USP_USD {
       base srv6-endpoint-type;
       description
         "End.X SID with the REPLACE-CSID PSP/USP/USD flavor";
       reference
         "RFC 9800";
     }

     identity END.T.REPLACE-CSID_USD {
       base srv6-endpoint-type;
       description
         "End.T USD SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }




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     identity END.T.REPLACE-CSID_PSP_USD {
       base srv6-endpoint-type;
       description
         "End.T PSP/USD SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.T.REPLACE-CSID_USP_USD {
       base srv6-endpoint-type;
       description
         "End.T USP/USD SID with the REPLACE-CSID lavor";
       reference
         "RFC 9800";
     }

     identity END.T.REPLACE-CSID_PSP_USP_USD {
       base srv6-endpoint-type;
       description
         "End.T PSP/USP/USD SID with the REPLACE-CSID flavor";
       reference
         "RFC 9800";
     }

     identity END.LBS.REPLACE-CSID {
       base srv6-endpoint-type;
       description
         "End behavior variant to modify the locator-block of the active CSID sequence in REPLACE-CSID";
       reference
         "RFC 9800";
     }

     identity END.XLBS.REPLACE-CSID {
       base srv6-endpoint-type;
       description
         "End.X behavior variant to modify the locator-block of the active CSID sequence in REPLACE-CSID";
       reference
         "RFC 9800";
     }

     identity END.DX1 {
       base srv6-endpoint-type;
       description
         "Endpoint with decapsulation and bit-stream cross-connect";
       reference
         "RFC 9801";
     }




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     identity END.DX1.NEXT-CSID {
       base srv6-endpoint-type;
       description
         "End.DX1 behavior for NEXT-CSID flavour";
       reference
         "RFC 9801";
     }

     identity END.DX1.REPLACE-CSID {
       base srv6-endpoint-type;
       description
         "End.DX1 behavior for REPLACE-CSID flavour";
       reference
         "RFC 9801";
     }


     /* 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



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     }

     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";
       // 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
     }

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



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     identity H.Encaps {
       base srv6-headend-type;
       description
         "Headend rule H.Encaps for SRv6 SIDlist imposition on L3 packet";
       reference "RFC 8986";
     }

     identity H.Encaps.Red {
       base srv6-headend-type;
       description
         "Reduced variant for H.Encaps headend rule";
       reference "RFC 8986";
     }

     identity H.Encaps.L2 {
       base srv6-headend-type;
       description
         "Headend rule H.Encaps.l2 on the received L2 frame";
       reference "RFC 8986";
     }

     identity H.Encaps.L2.Red {
       base srv6-headend-type;
       description
         "Reduced variant for H.Encaps.L2 headend rule";
       reference "RFC 8986";
     }

     identity H.Encaps.M {
       base srv6-headend-type;
       description
         "Headend rule where H.Encaps is applied to an MPLS packet after label lookup";
       reference "draft-ietf-spring-srv6-mpls-interworking-02";
     }

     identity H.Encaps.M.Red {
       base srv6-headend-type;
       description
         "Reduced variant of H.Encaps.M headend rule";
       reference "draft-ietf-spring-srv6-mpls-interworking-02";
     }

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




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     identity EXTIF-ACL-DROP-DA-SIDSPACE {
       base srv6-security-type;
       description
         "Support an ACL on the external interface that
         drops any traffic with DA within the internal SID space.";
       reference
         "RFC 8754 section 5.1";
     }

     identity INTIF-ACL-DROP-DA-SIDSPACE-SA-EXT  {
       base srv6-security-type;
       description
         "Support an ACL that drops any traffic on mySID as DA
         from a source SA that does not belong to internal address
         or SID space.)";
       reference
         "RFC 8754 section 5.1";
     }

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

     identity CNT-MySID-Success {
       base srv6-counter-type;
       description
         "Count packets and bytes traffic that matched mySID and
         was processed successfully";
       reference
         "RFC 8986 section 6";
     }

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

     typedef srv6-sid-compression-type {
       type enumeration {
         enum uncompressed { value 1; description "Uncompressed"; }
         enum csid-next { description "Compressed NEXT-CSID (aka uSID)"; }
         enum csid-replace { description "Compressed REPLACE-CSID"; }
       }
       description
         "SID [compression] type";
     }



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

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

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

     typedef srv6-locator-name-type {
       type string {
         length "1..59";
       }
       description "SRv6 locator name";
     }

     typedef srv6-locator-len {
       type uint8 {
         range "16 .. 96";
       }
       description
         "This type defines an SRv6 locator len with range
         constraints";
     }

     typedef srv6-locator-block-len {
       type uint8;
       description
         "This type defines an SRv6 locator block length in bits";
     }

     typedef srv6-locator-node-len {
       type uint8;
       description
         "This type defines an SRv6 locator node length in bits";
     }

     typedef srv6-sid-func-len {
       type uint8;
       description



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         "This type defines an SRv6 SID function length in bits";
     }

     typedef srv6-sid-arg-len {
       type uint8;
       description
         "This type defines an SRv6 SID argument length in bits";
     }

     typedef srv6-sid-pfxlen {
       type uint8 {
         range "16 .. 128";
       }
       default 128;
       description
         "This type defines a SID prefixlen with range constraints";
     }

     typedef sid-alloc-type {
       type enumeration {
         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";
     }




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     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";
     }

     identity static {
       base srv6-sid-owner-type;
       description "Static";
     }

     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 l3_lookup { description "L3 Lookup in a table"; }
         enum l2 { description "L2 next-hop"; }
         enum l2_lookup { description "L2 Lookup in a table"; }



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       }
       description
         "Forwarding Next-hop type";
     }

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

       leaf locator-block-length {
         type srv6-types:srv6-locator-block-len;
         description "SRv6 SID locator block length in bits";
       }
       leaf locator-node-length {
         type srv6-types:srv6-locator-node-len;
         description "SRv6 SID locator node length in bits";
       }
       leaf function-length {
         type srv6-types:srv6-sid-func-len;
         description "SRv6 SID function length in bits";
       }
       leaf argument-length {
         type srv6-types:srv6-sid-arg-len;
         description "SRv6 SID argument length in bits";
       }
     }

     grouping srv6-sid-structure-info-grouping {
       description "SRv6 SID structure info grouping";

      container sid-structure {
       config false;
       description "SID structure container";

       uses srv6-sid-structure-grouping;
      }
    }

     // Base identity for SID formats
     identity srv6-sid-format-type {
       description
         "Base identity from which SID format types are derived.";
     }

     identity srv6-sid-fmt-uc-1 {
       base srv6-sid-format-type;
       description
          "Uncompressed SID format with LBL=40, LNL=24, FL=16, and AL=16 or more.
          The locator length for this format is 64 bits.";



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     }

     identity srv6-sid-fmt-uc-128 {
       base srv6-sid-format-type;
       description
          "Uncompressed SID format that allows flexible values for LBL/LNL/FL/AL.";
     }

     identity srv6-sid-fmt-cnext-1616 {
       base srv6-sid-format-type;
       description "Compressed NEXT-CSID format using LBL=16, LNL=16,
                 FL=16 (or 32 for wide function), and AL=16 or more.
                 The locator length for this format is 32 bits.";
     }

     identity srv6-sid-fmt-cnext-3216 {
       base srv6-sid-format-type;
       description "Compressed NEXT-CSID format using LBL=32, LNL=16,
                 FL=16 (or 32 for wide function), and AL=16 or more.
                 The locator length for this format is 48 bits.";
     }

     identity srv6-sid-fmt-cnext-4816 {
       base srv6-sid-format-type;
       description "Compressed NEXT-CSID format using LBL=48, LNL=16,
                 FL=16 (or 32 for wide function), and AL=16 or more.
                 The locator length for this format is 64 bits.";
     }

     identity srv6-sid-fmt-cnext-6416 {
       base srv6-sid-format-type;
       description "Compressed NEXT-CSID format using LBL=64, LNL=16,
                 FL=16 (or 32 for wide function), and AL=16 or more.
                 The locator length for this format is 80 bits.";
     }
   } // module
   <CODE ENDS>

                       Figure 6: ietf-srv6-types.yang

5.2.  SRv6 Base

   This YANG module imports types defined in [RFC6991], [RFC8294],
   [RFC8343], [RFC8349], and [RFC9702].







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   <CODE BEGINS> file "ietf-srv6-base@2026-05-06.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";
       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 iana-msd-types {
       prefix iana-msd-types;
       reference "RFC 9702: YANG Data Model for MSD Types";
     }

     import ietf-segment-routing {
       prefix sr;
       reference "RFC 9020: YANG Data Model for Segment Routing";
     }

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



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

        Editor:   Pingping Yu
                  <mailto:susana.yu@huawei.com>

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

     revision 2026-05-06 {
       description



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         "Re-use MSD types (from iana-msd-types) for SRH";
       reference
         "RFC XXXX: YANG Data Model for SRv6 Base";
       // RFC Editor: replace XXXX with actual RFC number and remove
       // this note
     }

     revision 2025-07-07 {
       description
         "Adding compressed SID and few other missing def";
       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
         "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";



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       // 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
             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";
           }



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         }
     }

     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";
           }
         }

     }

    /*
     * 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 {
             when "../propagate = 'false'";
             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



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                         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 {
             when "../propagate = 'false'";
             type uint8;
             default 0;
             description "Set encapsulating outer IPv6 header's
                         Traffic-class field to specified value when
                         doing encapsulation";
           }

           leaf propagate {
             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-ucsid16-cfg-grouping {
       description "Uncompressed 16 bit FUNCT SID format config grouping";

      container id-block {
        description "Container for Id allocation corresponding to FUNCT";
        reference "RFC XXXX: YANG Data Model for SRv6 - Section 3.4.1";

        container explicit {
          description "Configure Explicit FUNCT parameters";
          leaf start {
            type uint16;
            description "Start of explicit block";
          }
          leaf size {
            type uint16;
            description "Size of explicit block";
          }
       }



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     }
   }


   grouping srv6-csid-next16-cfg-grouping {
       description "NEXT-CSID (16b uSID) common grouping";

      // CFG

      container local-id-block {
        description "Configure LIB parameters";
        reference "RFC XXXX: YANG Data Model for SRv6 - Section 3.4.2";

        leaf start {
          type uint16;
          description "LIB space follows GIB space. An implementation may chose
                       the default index for the start of LIB - e.g. LIB starting
                       from 0xE000. This configuration item allows to change the start of
                       LIB space as a user wishes to resize (expand or shrink)
                       it";
        }

        container explicit {
          description "Configure Explicit LIB parameters";

          leaf start {
            type uint16;
            description "Start of explicit LIB within LIB space";
          }
          leaf size {
            type uint16;
            description "Size (to shrink or expand) of explicit LIB";
          }
       }
     }
   }

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

      container sid-formats {
         description "Container for SRv6 SID formats";

         list format {
           key "type";
           description "SRv6 SID format";

           leaf type {



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             type identityref { base srv6-types:srv6-sid-format-type; }
             description "Format type";
           }

           // STATE
           leaf compression-type {
             type srv6-types:srv6-sid-compression-type;
             config false;
             description "Compression type";
           }
           leaf description {
             type string;
             config false;
             description "Format description";
           }

           uses srv6-types:srv6-sid-structure-info-grouping;

           // CFG
           container uncompressed-16 {
             when "derived-from-or-self(../type, 'srv6-sid-fmt-uc-1')" {
                  description "This container is valid only when the
                               SID format is one of the uncompressed types";
             }

             description "Configuration specific to uncompressed SID formats with 16b FUNCT";
             uses srv6-ucsid16-cfg-grouping;
           }

           container csid-next-16 {
             when "derived-from-or-self(../type, 'srv6-sid-fmt-cnext-1616') or
                   derived-from-or-self(../type, 'srv6-sid-fmt-cnext-3216') or
                   derived-from-or-self(../type, 'srv6-sid-fmt-cnext-6416')" {
                  description "This container is valid only when the
                               SID format is one of the 16bits NEXT-CSID";
             }

             description "Configuration specific to NEXT-CSID with 16b CSIDs";
             uses srv6-csid-next16-cfg-grouping;
           }
         }
      }
    }

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

          leaf operational-status {



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            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-remote-locator-stats-grouping {
      description "SRv6 Locator prefix accounting grouping";

      container traffic-accounting {
         description "SRv6 remote locator traffic accounting";

         container inbound {
            description "Per-Locator prefix inbound accounting";

            uses srv6-stats-in;
         }

         container outbound {
            description "Per-Locator prefix per-nexthop counters (aka LOC.INT.E)";

            list paths {
              key "interface next-hop";
              description "Forwarding path information";

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

              leaf next-hop {
                type inet:ipv6-address;
                description "The IPv6 address of the next-hop";
              }

              uses srv6-stats-out;
            }
        }
      }
   }



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    grouping srv6-remote-locators-state {

      description "SRv6 Remote Locator state grouping";

      list remote {
         key "prefix";
         config false;
         description "SRv6 remote locators' prefixes";

         leaf prefix {
           type inet:ipv6-prefix;
           description "Locator IPv6 prefix";
         }

         uses srv6-remote-locator-stats-grouping;
       }
     }

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

      container locators {
         description "SRv6 locators";

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

           leaf name {
             type srv6-types:srv6-locator-name-type;
             description "Locator name";
           }

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

           leaf format {
             type identityref { base srv6-types:srv6-sid-format-type; }
             mandatory true;
             description "SRv6 SID format";
           }

           container prefix {
             description "Specify locator prefix value";
             leaf address {



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               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 uint8 {
               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";
           }

           container node-sid-auto-allocation {
             description "Container for SID auto allocation";
             leaf behavior {
               type identityref { base srv6-types:srv6-endpoint-type; }

               description "As locator becomes operational, Node SIDs can be
                 auto allocated - e.g. in Uncompressed format locator, a reserved
                 FUNC value can be used and assigned for END SID; In
                 NEXT-CSID, the locator prefix address is used as
                 NEXT-CSID's END. These node SID are auto allocated with a
                 default variant (e.g. PSP-USD). This item allows a user to specify
                 a different variant.";
             }

             leaf disable {
                type boolean;
                default false;
                description "Set to true to disable auto allocation of SIDs";
             }
           }

           uses srv6-locator-state;
         }



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         uses srv6-remote-locators-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
             "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;
          }



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       }
     }


     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";
          }

          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 {

               leaf interface {
                 when "../../../../next-hop-type = 'l2'" {
                   description "This leaf is valid only when the nexthop type
                                is l2";
                 }
                 type if:interface-ref;
                  description "The outgoing Layer2 interface";
               }

               leaf lookup-table-id {
                 when "../../../../next-hop-type = 'l2_lookup'" {



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                   description "This leaf is valid only when the nexthop type
                                is L2 lookup (in a table)";
                 }
                 type uint32;
                 description "Lookup Table ID; Applicable to L2 VLAN,
                      L2 Ucast/Mcast table";
               }

               description "L2 information";
              }

             container l3 {
               when "../../../next-hop-type = 'ipv4' or ../../../next-hop-type = 'ipv6'" {
                 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;

               leaf lookup-table-id {
                 when "../../../../next-hop-type = 'l3_lookup'" {
                   description "This leaf is valid only when the nexthop type
                                is L3 lookup (in a table)";
                 }
                 type uint32;
                 description "L3 Lookup Table ID; Applicable to L3 unicast table";
                }

             //leaf vrf-name {
             //    type string;
             //     description " vrf name";
             //}


               description "L3 information";
             }

             uses path-out-sids-choice;



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           }

           description "Forwarding paths";
          }
       }
     }

     grouping srv6-sid-alloc-grouping {
      description "SRv6 SID allocation grouping";

      container allocation {
        description "SRv6 SID allocation container.";

        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";
          }
        }

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

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




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      container sids {

        description "My SID state";


            leaf sid-holdtime {
              type uint8 {
                range "0..60"; //The range of minutes is from 0 (disabled) to 60 minutes
              }
              units minutes;
              default 30;
              description "The holdtime for a stale or freed SID. The value 0
                           is used for an immediate release of an allocated SID.";
            }

            container counts {
              config false;
              description "Summary/aggregate counts for my SIDs";

              leaf allocated {
                type uint32;
                description "Total number of currently allocated SID";
              }

              leaf stale {
                type uint32;
                description "A stale SID is the a previously allocated SID which
                    is freed by the owner but not fully released due to holdtime";
               }
            }


        list sid {
          key "sid";
          config false;

          description "Per-SID";

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

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




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          uses srv6-locator;

          uses srv6-sid-alloc-grouping;

          uses local-sid-fwd-state;

          container counters {
            description "SRv6 per SID counters";

            container success {
              description "Counts SRv6 traffic received on local-SID
              prefix and processed successfully - see
              srv6-counter-types:CNT-MySID-Success (RFC 8986 section 6)";
              uses srv6-stats-in;
            }
          }
       }
      }
     }

     grouping srv6-support-ends {
       description "SRv6 End behavior support grouping";
      list end-behavior {
        key "type";
        description "End behavior support";

        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";
         }



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        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";

        list msds {
          key "msd-type";
          description "List of MSD types as defined in iana-msd-types";

          leaf msd-type {
            type identityref { base iana-msd-types:msd-base-srh; }
            description "MSD types";
          }

          leaf msd-value {
            type uint8;
            description "MSD value, in the range of 0-255.";
          }
         }
       }
     }

     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";
        }
       }



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      }

     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; }
          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";
       }




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       uses srv6-state-capabilities;
       uses srv6-encap;
       uses srv6-sid-formats;
       uses srv6-locators;
       uses srv6-state-sid;
      }
    }
    /* Notifications */

     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";
         }

        list owner {



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          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";
          }
        }
       }

       container requested {
         description "Requested assignment / bind";

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

        container requester {
          description "SID client";

          leaf type {
            type identityref { base srv6-types:srv6-sid-owner-type; }
            description "SID owner/client type";
          }

          leaf instance {
            type string;
            description "Client instance";
          }
        }
       }
     }
   } // module
   <CODE ENDS>

                       Figure 7: ietf-srv6-base.yang









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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.

   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 |
    +---------------------------------------------+------------+-----+

                                 Table 1

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



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    +==========+=================================+==========+=========+
    |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 |
    +----------+---------------------------------+----------+---------+

                                  Table 2

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

8.  References

8.1.  Normative References

   [I-D.ietf-bess-mvpn-evpn-sr-p2mp]
              Parekh, R., Voyer, D., Filsfils, C., Bidgoli, H., and Z.
              J. Zhang, "Multicast and Ethernet VPN with Segment Routing
              P2MP and Ingress Replication", Work in Progress, Internet-
              Draft, draft-ietf-bess-mvpn-evpn-sr-p2mp-18, 21 January
              2026, <https://datatracker.ietf.org/doc/html/draft-ietf-
              bess-mvpn-evpn-sr-p2mp-18>.

   [I-D.ietf-rtgwg-srv6-egress-protection]
              He, T., Hu, Z., Chen, H., Toy, M., and C. Cao, "SRv6 Path
              Egress Protection", Work in Progress, Internet-Draft,
              draft-ietf-rtgwg-srv6-egress-protection-23, 9 April 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-rtgwg-
              srv6-egress-protection-23>.

   [I-D.ietf-spring-sr-service-programming]
              Abdelsalam, A., 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-12, 3 November 2025,
              <https://datatracker.ietf.org/doc/html/draft-ietf-spring-
              sr-service-programming-12>.









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   [I-D.ietf-spring-srv6-mpls-interworking]
              Agrawal, S., Filsfils, C., Voyer, D., Dawra, G., Li, Z.,
              and S. Hegde, "SRv6 and MPLS interworking", Work in
              Progress, Internet-Draft, draft-ietf-spring-srv6-mpls-
              interworking-02, 7 February 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-spring-
              srv6-mpls-interworking-02>.

   [I-D.ietf-spring-srv6-path-segment]
              Li, C., Cheng, W., Zeng, G., Dhody, D., and Y. Zhu, "Path
              Segment Identifier (PSID) in SRv6 (Segment Routing in
              IPv6)", Work in Progress, Internet-Draft, draft-ietf-
              spring-srv6-path-segment-15, 15 March 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-spring-
              srv6-path-segment-15>.

   [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>.

   [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>.





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   [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>.

   [RFC8407]  Bierman, A., "Guidelines for Authors and Reviewers of
              Documents Containing YANG Data Models", 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>.






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   [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>.

   [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>.

   [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>.

   [RFC9491]  Guichard, J., Ed. and J. Tantsura, Ed., "Integration of
              the Network Service Header (NSH) and Segment Routing for
              Service Function Chaining (SFC)", RFC 9491,
              DOI 10.17487/RFC9491, November 2023,
              <https://www.rfc-editor.org/info/rfc9491>.

   [RFC9524]  Voyer, D., Ed., Filsfils, C., Parekh, R., Bidgoli, H., and
              Z. Zhang, "Segment Routing Replication for Multipoint
              Service Delivery", RFC 9524, DOI 10.17487/RFC9524,
              February 2024, <https://www.rfc-editor.org/info/rfc9524>.

   [RFC9702]  Qu, Y., Lindem, A., Litkowski, S., and J. Tantsura, "YANG
              Data Model for Maximum Segment Identifier (SID) Depth
              (MSD) Types and MPLS MSD", RFC 9702, DOI 10.17487/RFC9702,
              January 2025, <https://www.rfc-editor.org/info/rfc9702>.

   [RFC9800]  Cheng, W., Ed., Filsfils, C., Li, Z., Decraene, B., and F.
              Clad, Ed., "Compressed SRv6 Segment List Encoding",
              RFC 9800, DOI 10.17487/RFC9800, June 2025,
              <https://www.rfc-editor.org/info/rfc9800>.

   [RFC9801]  Gringeri, S., Whittaker, J., Leymann, N., Schmutzer, C.,
              Ed., and C. Brown, "Private Line Emulation over Packet
              Switched Networks", RFC 9801, DOI 10.17487/RFC9801, July
              2025, <https://www.rfc-editor.org/info/rfc9801>.

8.2.  Informative References



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Appendix A.  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.

Appendix B.  Contributors

   Zhibo Hu
   Huawei Technologies
   Email: huzhibo@huawei.com

   Sonal Agarwal
   Individual
   
   Katsuhiro Horiba
   Individual
   Email: katsuhiro.horiba@gmail.com>

   Himanshu Shah
   Ciena Corporation
   Email: hshah@ciena.com

   Iftekhar Hussain
   Individual
   Email: iftekhar_hussain@yahoo.com

   Ahmed AbdelSalam
   Cisco Systems
   Email: ahabdels@cisco.com

   Daniel Voyer
   Individual
   Email: danvoyerwork@gmail.com

   Hani Elmalky
   Individual
   Email: helmalky@google.com


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Authors' Addresses

   Kamran Raza
   Cisco Systems
   Email: skraza@cisco.com


   Jaganbabu Rajamanickam
   Cisco Systems
   Email: jrajaman@cisco.com


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


   Pingping Yu
   Huawei Technologies
   Email: susana.yu@huawei.com


   Xufeng Liu
   Individual
   Email: xufeng.liu.ietf@gmail.com




















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