SPRING Working Group                                            L. Gong
Internet Draft                                             China Mobile
Intended status: Standards Track                                 C. Lin
Expires: June 12, 2025                             New H3C Technologies
                                                                R. Chen
                                                        ZTE Corporation
                                                                 Y. Qiu
                                                   New H3C Technologies
                                                      December 12, 2024


                    YANG Data Model for SR Policy Group
                 draft-gong-spring-sr-policy-group-yang-01


Abstract

   This document defines YANG data models for Segment Routing (SR)
   Policy group that can be used for configuring, instantiating, and
   managing SR Policy groups. The model is generic and apply equally to
   the MPLS and SRv6 instantiations of SR policy groups.

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
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   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on June 12, 2025.

Copyright Notice

   Copyright (c) 2024 IETF Trust and the persons identified as the
   document authors. All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document. Please review these documents
   carefully, as they describe your rights and restrictions with
   respect to this document. Code Components extracted from this
   document must include Simplified BSD License text as described in

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

Table of Contents


   1. Introduction ................................................ 3
      1.1. Terminology ............................................ 3
      1.2. Conventions Used in This Document ...................... 3
      1.3. Tree Diagrams .......................................... 4
      1.4. Prefixes in Data Node Names ............................ 4
   2. Model Overview .............................................. 4
   3. SR Policy Group YANG Module ................................. 4
      3.1. Tree View .............................................. 4
      3.2. Yang Module ............................................ 6
   4. Security Considerations .................................... 12
   5. IANA Considerations ........................................ 12
   6. References ................................................. 12
      6.1. Normative References .................................. 12
      6.2. Informative References ................................ 13
   Authors' Addresses ............................................ 14






























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1. Introduction

   The Network Configuration Protocol (NETCONF) [RFC6241] 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.

   [I-D.cheng-spring-sr-policy-group] describes SR policy Group in MPLS
   and IPv6 environments. It illustrates some use cases for parent SR
   policy and SR Policy Group to provide best practice cases for
   operators.

   [I-D.ietf-spring-sr-policy-yang] defines a YANG data model for SR
   Policy that can be used for configuring, instantiating, and managing
   SR policies.

   This document defines YANG data models for SR Policy group that can
   be used for configuring, instantiating, and managing SR Policy
   groups. The model is generic and apply equally to the MPLS and SRv6
   instantiations of SR policy groups.



1.1. Terminology

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

   o augment

   o data model

   o data node

   o identity

   o module

   The definitions of the basic terms are identical to those found in
   Segment Routing Architecture [RFC8402], Segment Routing Policy
   Architecture [RFC9256], and Segment Routing Policy group [I-D.cheng-
   spring-sr-policy-group].

1.2. Conventions Used in This Document

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

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1.3. Tree Diagrams

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

1.4. Prefixes in Data Node Names

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

   +=================+======================+=======================+

   | Prefix          | YANG module          | Reference             |

   +=================+======================+=======================+

   | rt              | ietf-routing         | [RFC8349]             |

   +-----------------+----------------------+-----------------------+

                                Table 1

2. Model Overview

   SR Policy group YANG data model are defined in this document.

   The ietf-sr-policy-group.yang data model provides the methods for
   configuring and managing SR Policy group. It includes:

   *  Configuration of SR Policy group: Container that defines list of
      policy groups with their attributes, such as service
      identification methods, mapping relationship between DSCP and
      color, mapping relationship between service class and color etc.

   *  The operational state of SR Policy group, such as the state
      related to configuration items.

3. SR Policy Group YANG Module

3.1. Tree View

   Following diagram depicts high level yang organization and hierarchy
   for an SR policy group specification:





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       Segment-routing
          Traffic-engineering
          + attributes
          |   + ......
          + policies
          |    policy* [color endpoint]
          |       ......
          + sr-policy-groups
              group* [group-color]
                + name
                + description
                + forward-based-dscp
                |  + best-effort-dscp-list
                |  + dscp-mismatch-drop-v4
                |  + dscp-mismatch-drop-v6
                |  + dscp-color-mapping-entries
                |       mapping-entry* [policy-color dataplane]
                |          dscp-list
                |          ......
                + forward-based-dot1q
                |  + best-effort-dot1q-list
                |  + dot1q-mismatch-drop
                |  + dot1q-color-mapping-entries
                |       mapping-entry* [policy-color]
                |          dot1q-list
                |          ......
                + forward-based-serviceclass
                   + best-effort-classlist
                   + class-mismatch-drop
                   + class-color-mapping-entries
                        mapping-entry* [policy-color]
                           class-list
                           ......

   SR Policy group YANG data model augments "/rt:routing" specified in
   [RFC8349] and specifies the configuration and operational state to
   manage the SR Policy groups.

   The complete tree of the ietf-sr-policy-group.yang data model is
   represented as following. See [RFC8340] for an explanation of the
   symbols used.









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   module: ietf-sr-policy-group
     augment /rt:routing:
       +--rw sr-policy-groups
          +--rw group* [group-color]
             +--rw group-color                   uint32
             +--rw name?                         string
             +--rw description?                  string
             +--rw service-distinguish-method    enumeration
             +--rw forward-based-dscp
             |  +--rw best-effort-dscp-list-v4   string
             |  +--rw best-effort-dscp-list-v6   string
             |  +--rw dscp-mismatch-drop         Boolean
             |  +--rw dscp-color-mapping-entries
             |  |  +--rw mapping-entry* [policy-color dataplane]
             |  |  |  +--rw policy-color         uint32
             |  |  |  +--rw dataplane            dataplane-type
             |  |  |  +--rw dscp-list            string
             |  |  |  +--rw is-as-default?       Boolean
             +--rw forward-based-dot1q
             |  +--rw best-effort-dot1q          string
             |  +--rw dot1q-mismatch-drop        Boolean
             |  +--rw dot1q-color-mapping-entries
             |  |  +--rw mapping-entry* [policy-color]
             |  |  |  +--rw policy-color         uint32
             |  |  |  +--rw dot1q-list           string
             |  |  |  +--rw is-as-default?       Boolean
             +--rw forward-based-serviceclass
                +--rw best-effort-classlist      string
                +--rw class-mismatch-drop        Boolean
                +--rw class-color-mapping-entries
                   +--rw mapping-entry* [policy-color]
                      +--rw policy-color         uint32
                      +--rw class-list           string
                      +--rw is-as-default?       Boolean

3.2. Yang Module

   <CODE BEGINS> file "ietf-sr-policy-group@2024-05-22.yang"
   module ietf-sr-policy-group {
     yang-version "1.1";
     namespace "urn:ietf:params:xml:ns:yang:ietf-sr-policy-group";
     prefix "sr-policy-group";

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


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     organization
       "IETF SPRING Working Group";

     contact
       "TBD";

     description
       "This module describes a YANG model for configuring and managing
        SR Policy Groups.

        This YANG model conforms to the Network Management
        Datastore Architecture (NMDA) as described in RFC 8342.

        Copyright (c) 2024 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 Revised BSD License set
        forth in Section 4.c of the IETF Trust's Legal Provisions
        Relating to IETF Documents
        (https://trustee.ietf.org/license-info).

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

        The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL
        NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'NOT RECOMMENDED',
        'MAY', and 'OPTIONAL' in this document are to be interpreted as
        described in BCP 14 (RFC 2119) (RFC 8174) when, and only when,
        they appear in all capitals, as shown here.";

     revision 2024-05-22 {
       description
         "Initial Version";
       reference
         "draft-ietf-spring-sr-policy-yang-02, YANG Data Model for
          Segment Routing Policy";
     }

     typedef dataplane-type {
       description "Dataplane type of segment routing";
       type enumeration {
         enum mpls {
           value 1;
             description "Segment-routing MPLS";
         }
         enum srv6 {
           value 2;
             description "Segment-routing v6";

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         }
       }
     }

     augment "/rt:routing" {
       description
         "SR Policy Group augmentation to the segment routing traffic
          engineering model.";
       container sr-policy-groups {
         description
           "Configuration parameters of SR Policy Group.";
         list sr-policy-group {
           key "group-color";
           description
             "Each entry contains parameters for SR Policy Group
              identifiedby the 'color' key.";
           leaf group-color {
             type uint32 {
               range "1..4294967295";
             }
             mandatory true;
             description "Color associated with the policy group";
           }
           leaf name {
             type string {
               length "1..59";
             }
             description "SR Policy group name";
           }
           leaf description {
             type string;
             description "Description of the policy group";
           }
           leaf service-distinguish-method {
             type enumeration {
               enum DSCP-based {
                 value 1;
                 description "Distinguish service type based on DSCP
                   in the message";
               }
               enum dot1q-based {
                 value 2;
                 description "Distinguish service type based on dot1q";
               }
               enum ServiceClass-based {
                 value 3;
                 description "Distinguish service type based on service
                   class";
               }
               enum None {

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                 value 4;
                 description "Not configure service type recognition
                   method";
               }
             }
             description "Service traffic steering methods within SR
               policy group";
           }
           container forward-based-dscp {
             description "parameters of DSCP based steering traffic
               for SR policy group";
             leaf best-effort-dscp-list-v4 {
               type string;
               description "DSCP values for IPv4 packets matching
                 best-effort. It is a comma-separated list of DSCP
                 values. Each item can be an individual DSCP value
                 or a DSCP value range. Use a tilde (~) to separate
                 the start and end DSCP values of a range.
                 Example: 1,2,3,5~8.";
             }
             leaf best-effort-dscp-list-v6 {
               type string;
               description "DSCP values for IPv6 packets matching
                 best-effort. It is a comma-separated list of DSCP
                 values. Each item can be an individual DSCP value
                 or a DSCP value range. Use a tilde (~) to separate
                 the start and end DSCP values of a range.
                 Example: 1,2,3,5~8.";
             }
             leaf dscp-mismatch-drop {
               type boolean;
               default "false";
               description "When all DSCP values configured for
                 best effort forwarding and SR policy forwarding do
                 not match, and no default forwarding path is
                 specified, discard traffic.";
             }
             container dscp-color-mapping-entries {
               description "DSCP-color mapping table";
               list mapping-entry {
                 key "policy-color dataplane";
                 description "This table contains color-DSCP mappings
                   for an SRv6 policy group.";
                 leaf policy-color {
                   type uint32 {
                     range "1..4294967295";
                   }
                   mandatory true;
                   description "Color associated with the policy
                     group";

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                 }
                 leaf dataplane {
                   type dataplane-type;
                   mandatory true;
                   description "The data plane type of the mapping
                     relationship between DSCP and color";
                 }
                 leaf dscp-list {
                   type string;
                   description "DSCP values for packets matching.
                     It is a comma-separated list of DSCP values.
                     Each item can be an individual DSCP value or
                     a DSCP value range. Use a tilde (~) to separate
                     the start and end DSCP values of a range.
                    Example: 1,2,3,5~8.";
                 }
                 leaf is-as-default {
                   type boolean;
                   default false;
                   description "Whether to use the SRv6 policy
                     with this color as the default policy for
                     packets";
                 }
               }
             }
           }
           container forward-based-dot1q {
             description "parameters of dot1q based steering
               traffic for SR policy group";
             leaf best-effort-dot1q-list {
               type string;
               description "Dot1q values for packets matching
                 best-effort. It is a comma-separated list of
                 dot1q values. Each item can be an individual
                 dot1q value or a dot1q value range. Use a
                 tilde (~) to separate the start and end dot1q
                 values of a range. Example: 1,2,3,5~8.";
             }
             leaf dot1q-mismatch-drop {
               type boolean;
               default "false";
               description "When all dot1q values configured
                 for best effort forwarding and SR policy
                 forwarding do not match, and no default
                 forwarding path is specified, discard traffic.";
             }
             container dot1q-color-mapping-entries {
               description "Dot1q-color mapping table";
               list mapping-entry {
                 key "policy-color";

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                 description "This table contains color-dot1q
                   mappings for an SRv6 policy group.";
                 leaf policy-color {
                   type uint32 {
                     range "1..4294967295";
                   }
                   mandatory true;
                   description "Color associated with the policy
                     group";
                 }
                 leaf dot1q-list {
                   type string;
                   description "Dot1q values for packets
                     matching. It is a comma-separated list of
                     dot1q values. Each item can be an individual
                     dot1q value or a dot1q value range. Use a tilde
                     (~) to separate the start and end dot1q values
                     of a range. Example: 1,2,3,5~8.";
                 }
                 leaf is-as-default {
                   type boolean;
                   default false;
                   description "Whether to use the SRv6 policy
                     with this color as the default policy for
                     packets";
                 }
               }
             }
             container class-color-mapping-entries {
               description "Serviceclass-color mapping table";
               list mapping-entry {
                 key "policy-color";
                 description "This table contains color-serviceclass
                   mappings for an SRv6 policy group.";
                 leaf policy-color {
                   type uint32 {
                     range "1..4294967295";
                   }
                   mandatory true;
                   description "Color associated with the policy
                     group";
                 }
                 leaf class-list {
                   type string;
                   description "Service class values for packets
                     matching. It is a comma-separated list of
                     service class values. Each item can be an
                     individual service class value or a service
                     class value range. Use a tilde (~) to separate
                     the start and end service class values of

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                     a range. Example: 1,2,3,5~8.";
                 }
                 leaf is-as-default {
                   type boolean;
                   default false;
                   description "Whether to use the SRv6 policy
                     with this color as the default policy for
                     packets";
                 }
               }
             }
           }
         }
       } // sr-policy-group
     } // augment
   }
   <CODE ENDS>

4. Security Considerations

   TBD

5. IANA Considerations

   TBD

6. References

6.1. Normative References

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

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

   [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>.

   [I-D.cheng-spring-sr-policy-group] Cheng, W., Jiang, W., Lin, C.,
             Qiu, Y., Wei, Y., Chen, R., Liang, R., "SR Policy Group",
             draft-cheng-spring-sr-policy-group-03 (work in progress),
             September 2023.




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   [I-D.ietf-spring-sr-policy-yang] Raza, K., Sawaya, R., Shunwan, Z.,
             Voyer, D., Durrani, M., Matsushima, S., Beeram, V., "YANG
             Data Model for Segment Routing Policy", draft-ietf-spring-
             sr-policy-yang-02 (work in progress), September 2022.

6.2. Informative References

   XXX










































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Authors' Addresses

   Liyan Gong
   China Mobile
   China
   Email: gongliyan@chinamobile.com

   Changwang Lin
   New H3C Technologies
   China
   Email: linchangwang.04414@h3c.com

   Ran Chen
   ZTE Corporation
   China
   Email: chen.ran@zte.com.cn


   Yuanxiang Qiu
   New H3C Technologies
   China
   Email: qiuyuanxiang@h3c.com




























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