



Internet Engineering Task Force (IETF)                           H. Zhao
Request for Comments: 9398                                      Ericsson
Category: Standards Track                                         X. Liu
ISSN: 2070-1721                                                Alef Edge
                                                                  Y. Liu
                                                            China Mobile
                                                         M. Panchanathan
                                                     Cisco Systems, Inc.
                                                            M. Sivakumar
                                                                 Juniper
                                                                May 2023


  A YANG Data Model for Internet Group Management Protocol (IGMP) and
            Multicast Listener Discovery (MLD) Proxy Devices

Abstract

   This document defines a YANG data model that can be used to configure
   and manage Internet Group Management Protocol (IGMP) or Multicast
   Listener Discovery (MLD) Proxy devices.  The YANG module in this
   document conforms to the Network Management Datastore Architecture
   (NMDA).

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 7841.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   https://www.rfc-editor.org/info/rfc9398.

Copyright Notice

   Copyright (c) 2023 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Revised BSD License text as described in Section 4.e of the
   Trust Legal Provisions and are provided without warranty as described
   in the Revised BSD License.

Table of Contents

   1.  Introduction
     1.1.  Terminology
     1.2.  Tree Diagrams
     1.3.  Prefixes in Data Node Names
   2.  Design of Data Model
     2.1.  Overview
     2.2.  Optional Features
     2.3.  Position of Address Family in Hierarchy
   3.  Module Structure
     3.1.  IGMP Proxy Configuration and Operational State
     3.2.  MLD Proxy Configuration and Operational State
   4.  IGMP/MLD Proxy YANG Module
   5.  Security Considerations
   6.  IANA Considerations
     6.1.  IETF XML Registry
     6.2.  YANG Module Names Registry
   7.  References
     7.1.  Normative References
     7.2.  Informative References
   Appendix A.  Data Tree Example
   Authors' Addresses

1.  Introduction

   This document defines a YANG data model [RFC7950] for the management
   of Internet Group Management Protocol (IGMP) or Multicast Listener
   Discovery (MLD) Proxy devices [RFC4605].  The YANG module in this
   document conforms to the Network Management Datastore Architecture as
   defined in [RFC8342].

1.1.  Terminology

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

   *  augment

   *  data model

   *  data node

   *  identity

   *  module

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

   IGMP:  Internet Group Management Protocol [RFC3376].

   MLD:  Multicast Listener Discovery [RFC3810].

   PIM:  Protocol Independent Multicast [RFC7761].

1.2.  Tree Diagrams

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

1.3.  Prefixes in Data Node Names

   In this document, names of data nodes and other data model objects
   are often used without a prefix, as long as the context clearly
   indicates the YANG module in which 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 |
               +==========+====================+===========+
               | inet     | ietf-inet-types    | [RFC6991] |
               +----------+--------------------+-----------+
               | if       | ietf-interfaces    | [RFC8343] |
               +----------+--------------------+-----------+
               | rt       | ietf-routing       | [RFC8349] |
               +----------+--------------------+-----------+
               | rt-types | ietf-routing-types | [RFC8294] |
               +----------+--------------------+-----------+
               | pim-base | ietf-pim-base      | [RFC9128] |
               +----------+--------------------+-----------+

                  Table 1: Prefixes and Corresponding YANG
                                  Modules

2.  Design of Data Model

   The model covers forwarding based on IGMP and MLD proxying [RFC4605].
   One goal of this document is to define a data model that provides a
   common user interface for IGMP/MLD Proxy devices.

2.1.  Overview

   The model defined in this document has all the common building blocks
   for IGMP/MLD Proxy devices and can be used to configure those
   devices.  The operational state data and statistics can also be
   retrieved via this model.

2.2.  Optional Features

   This model is designed to represent the basic capability subsets of
   IGMP/MLD Proxies.  The main design goals of this document are that
   (1) the basic capabilities described in the model will be supported
   by any major implementations that exist at the time of this writing
   and (2) the configuration of all implementations meeting the
   specifications will be easy to express through some combination of
   the optional features in the model and simple vendor augmentations.

   This model declares two features representing capabilities that not
   all deployed devices support.  One feature is called "igmp-proxy",
   and the other feature is called "mld-proxy".  Either or both features
   could be implemented; this would provide more choices for vendors.

2.3.  Position of Address Family in Hierarchy

   IGMP Proxies only support IPv4, while MLD Proxies only support IPv6.
   The data model defined in this document can be used for both IPv4 and
   IPv6 address families.

   This document defines IGMP Proxies and MLD Proxies in separate schema
   branches in the structure.  The benefits of this technique are as
   follows:

   *  The model can support IGMP Proxies (IPv4), MLD Proxies (IPv6), or
      both, optionally and independently.  Such flexibility cannot be
      achieved cleanly with a combined branch.

   *  The structure is consistent with other YANG data models such as
      the model defined in [RFC8652], which uses separate branches for
      IPv4 and IPv6.

   *  Having separate branches for IGMP Proxies and MLD Proxies allows
      minor differences in their behavior to be modeled more simply and
      cleanly.  The two branches can better support different features
      and node types.

3.  Module Structure

   This model augments the core routing data model specified in
   [RFC8349].

      +--rw routing
         +--rw router-id?
         +--rw control-plane-protocols
         |  +--rw control-plane-protocol* [type name]
         |     +--rw type
         |     +--rw name
         |     +--rw igmp-proxy <= Augmented by this model
                        ...
         |     +--rw mld-proxy  <= Augmented by this model

   The "igmp-proxy" container instantiates an IGMP Proxy.  The "mld-
   proxy" container instantiates an MLD Proxy.

3.1.  IGMP Proxy Configuration and Operational State

   The YANG module augments /rt:routing/rt:control-plane-protocols/
   rt:control-plane-protocol to add the igmp-proxy container.

   All attributes related to IGMP Proxies are defined in the igmp-proxy
   container.  The read-write attributes represent configurable data.
   The read-only attributes represent state data.

   The igmp-version parameter represents the IGMP protocol version; the
   default value is 2.  If the value of the "enabled" parameter is
   "true", it means that the IGMP Proxy is enabled.

   The interface list under igmp-proxy contains upstream interfaces for
   an IGMP Proxy.  A constraint is provided to make sure that the
   upstream interface for the IGMP Proxy is not configured to use PIM.

   To configure a downstream interface for an IGMP Proxy, the ability to
   enable IGMP on that interface is needed.  This is defined in "A YANG
   Data Model for the Internet Group Management Protocol (IGMP) and
   Multicast Listener Discovery (MLD)" [RFC8652].

   augment /rt:routing/rt:control-plane-protocols
             /rt:control-plane-protocol:
     +--rw igmp-proxy! {igmp-proxy}?
        +--rw interfaces
           +--rw interface* [name]
              +--rw name                     if:interface-ref
              +--rw igmp-version?            uint8
              +--rw enabled?                 boolean
              +--rw sender-source-address?   inet:ipv4-address-no-zone
              +--ro group* [group-address]
                 +--ro group-address
                 |       rt-types:ipv4-multicast-group-address
                 +--ro up-time?         uint32
                 +--ro filter-mode      enumeration
                 +--ro source* [source-address]
                    +--ro source-address
                    |       inet:ipv4-address-no-zone
                    +--ro up-time?                uint32
                    +--ro downstream-interface* [name]
                       +--ro name    if:interface-ref

3.2.  MLD Proxy Configuration and Operational State

   The YANG module augments /rt:routing/rt:control-plane-protocols/
   rt:control-plane-protocol to add the mld-proxy container.

   All attributes related to MLD Proxies are defined in the mld-proxy
   container.  The read-write attributes represent configurable data.
   The read-only attributes represent state data.

   The mld-version parameter represents the MLD protocol version; the
   default value is 2.  If the value of the "enabled" parameter is
   "true", it means that the MLD Proxy is enabled.

   The interface list under mld-proxy contains upstream interfaces for
   an MLD Proxy.  A constraint is provided to make sure that the
   upstream interface for the MLD Proxy is not configured to use PIM.

   To configure a downstream interface for an MLD Proxy, enable MLD on
   that interface.  This is defined in "A YANG Data Model for the
   Internet Group Management Protocol (IGMP) and Multicast Listener
   Discovery (MLD)" [RFC8652].

   augment /rt:routing/rt:control-plane-protocols
             /rt:control-plane-protocol:
     +--rw mld-proxy! {mld-proxy}?
        +--rw interfaces
           +--rw interface* [name]
              +--rw name                     if:interface-ref
              +--rw mld-version?             uint8
              +--rw enabled?                 boolean
              +--rw sender-source-address?   inet:ipv6-address-no-zone
              +--ro group* [group-address]
                 +--ro group-address
                 |       rt-types:ipv6-multicast-group-address
                 +--ro up-time?         uint32
                 +--ro filter-mode      enumeration
                 +--ro source* [source-address]
                    +--ro source-address
                    |       inet:ipv6-address-no-zone
                    +--ro up-time?                uint32
                    +--ro downstream-interface* [name]
                       +--ro name    if:interface-ref

4.  IGMP/MLD Proxy YANG Module

   This module references [RFC4605], [RFC6991], [RFC8294], [RFC8343],
   [RFC8349], and [RFC9128].

   <CODE BEGINS> file "ietf-igmp-mld-proxy@2023-05-30.yang"
   module ietf-igmp-mld-proxy {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-igmp-mld-proxy";
     prefix igmp-mld-proxy;

     import ietf-inet-types {
       prefix inet;
       reference
         "RFC 6991: Common YANG Data Types";
     }
     import ietf-interfaces {
       prefix if;
       reference
         "RFC 8343: A YANG Data Model for Interface Management";
     }
     import ietf-routing {
       prefix rt;
       reference
         "RFC 8349: A YANG Data Model for Routing Management (NMDA
          Version)";
     }
     import ietf-routing-types {
       prefix rt-types;
       reference
         "RFC 8294: Common YANG Data Types for the Routing Area";
     }
     import ietf-pim-base {
       prefix pim-base;
       reference
         "RFC 9128: YANG Data Model for Protocol Independent Multicast
          (PIM)";
     }

     organization
       "IETF PIM Working Group";
     contact
       "WG Web:   <https://datatracker.ietf.org/wg/pim/>
        WG List:  <mailto:pim@ietf.org>

        Editors:  Hongji Zhao
                  <mailto:hongji.zhao@ericsson.com>

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

                  Yisong Liu
                  <mailto:liuyisong@chinamobile.com>

                  Mani Panchanathan
                  <mailto:mapancha@cisco.com>

                  Mahesh Sivakumar
                  <mailto:sivakumar.mahesh@gmail.com>";
     description
       "This module defines a collection of YANG definitions common for
        all Internet Group Management Protocol (IGMP) and Multicast
        Listener Discovery (MLD) Proxy devices.

        Copyright (c) 2023 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 9398; see the
        RFC itself for full legal notices.";

     revision 2023-05-30 {
       description
         "Initial revision.";
       reference
         "RFC 9398: A YANG Data Model for Internet Group Management
          Protocol (IGMP) and Multicast Listener Discovery (MLD)
          Proxy Devices";
     }

     /*
      * Features
      */

     feature igmp-proxy {
       description
         "Support for the IGMP Proxy protocol.";
       reference
         "RFC 4605: Internet Group Management Protocol (IGMP) /
          Multicast Listener Discovery (MLD)-Based Multicast Forwarding
          ('IGMP/MLD Proxying')";
     }

     feature mld-proxy {
       description
         "Support for the MLD Proxy protocol.";
       reference
         "RFC 4605: Internet Group Management Protocol (IGMP) /
          Multicast Listener Discovery (MLD)-Based Multicast Forwarding
          ('IGMP/MLD Proxying')";
     }

     /*
      * Identities
      */

     identity igmp-proxy {
       base rt:control-plane-protocol;
       description
         "IGMP Proxy protocol.";
     }

     identity mld-proxy {
       base rt:control-plane-protocol;
       description
         "MLD Proxy protocol.";
     }

     /*
      * Groupings
      */

     grouping per-interface-config-attributes {
       description
         "'config' attributes as listed under an interface entry.";
       leaf enabled {
         type boolean;
         default "true";
         description
           "Set the value to 'true' to enable the IGMP/MLD Proxy.";
       }
     } // per-interface-config-attributes

     grouping state-group-attributes {
       description
         "State group attributes.";
       leaf up-time {
         type uint32;
         units "seconds";
         description
           "The elapsed time for (S,G) or (*,G).";
       }
       leaf filter-mode {
         type enumeration {
           enum include {
             description
               "In 'include' mode, reception of packets sent
                to the specified multicast address is requested
                only from those IP source addresses listed in the
                'source' list parameter.";
           }
           enum exclude {
             description
               "In 'exclude' mode, reception of packets sent
                to the given multicast address is requested
                from all IP source addresses except those
                listed in the 'source' list parameter.";
           }
         }
         mandatory true;
         description
           "Filter mode for a multicast group.
            May be either 'include' or 'exclude'.";
       }
     } // state-group-attributes

     /* augments */

     augment "/rt:routing/rt:control-plane-protocols"
           + "/rt:control-plane-protocol" {
       when "derived-from-or-self(rt:type, "
          + "'igmp-mld-proxy:igmp-proxy')" {
         description
           "This augmentation is only valid for IGMP Proxies.";
       }
       description
         "IGMP Proxy augmentation to routing control plane protocol
          configuration and state.";
       container igmp-proxy {
         if-feature "igmp-proxy";
         presence "IGMP Proxy configuration.";
         description
           "IGMP Proxy instance configuration.";
         container interfaces {
           description
             "Contains a list of upstream interfaces.";
           list interface {
             key "name";
             description
               "List of upstream interfaces.";
             leaf name {
               type if:interface-ref;
               must 'not( current() = /rt:routing'
                  + '/rt:control-plane-protocols/pim-base:pim'
                  + '/pim-base:interfaces/pim-base:interface'
                  + '/pim-base:name )' {
                 description
                   "The upstream interface for the IGMP Proxy
                    must not be configured to use PIM.";
               }
               description
                 "The upstream interface name.";
             }
             leaf igmp-version {
               type uint8 {
                 range "1..3";
               }
               default "2";
               description
                 "IGMP version.";
             }
             uses per-interface-config-attributes;
             leaf sender-source-address {
               type inet:ipv4-address-no-zone;
               description
                 "The sender source address of an
                  IGMP membership report message or leave message.";
             }
             list group {
               key "group-address";
               config false;
               description
                 "List of the multicast groups in the membership
                  database built on this upstream interface.";
               leaf group-address {
                 type rt-types:ipv4-multicast-group-address;
                 description
                   "Multicast group address.";
               }
               uses state-group-attributes;
               list source {
                 key "source-address";
                 description
                   "Multicast source information
                    for the multicast group.";
                 leaf source-address {
                   type inet:ipv4-address-no-zone;
                   description
                     "Multicast source address.";
                 }
                 leaf up-time {
                   type uint32;
                   units "seconds";
                   description
                     "The elapsed time for (S,G) or (*,G).";
                 }
                 list downstream-interface {
                   key "name";
                   description
                     "List of downstream interfaces.";
                   leaf name {
                     type if:interface-ref;
                     description
                       "Downstream interfaces
                        for each upstream interface.";
                   }
                 }
               } // list source
             } // list group
           } // interface
         } // interfaces
       }
     }

     augment "/rt:routing/rt:control-plane-protocols"
           + "/rt:control-plane-protocol" {
       when "derived-from-or-self(rt:type, "
          + "'igmp-mld-proxy:mld-proxy')" {
         description
           "This augmentation is only valid for MLD Proxies.";
       }
       description
         "MLD Proxy augmentation to routing control plane protocol
          configuration and state.";
       container mld-proxy {
         if-feature "mld-proxy";
         presence "MLD Proxy configuration.";
         description
           "MLD Proxy instance configuration.";
         container interfaces {
           description
             "Contains a list of upstream interfaces.";
           list interface {
             key "name";
             description
               "List of upstream interfaces.";
             leaf name {
               type if:interface-ref;
               must 'not( current() = /rt:routing'
                  + '/rt:control-plane-protocols/pim-base:pim'
                  + '/pim-base:interfaces/pim-base:interface'
                  + '/pim-base:name )' {
                 description
                   "The upstream interface for the MLD Proxy
                    must not be configured to use PIM.";
               }
               description
                 "The upstream interface name.";
             }
             leaf mld-version {
               type uint8 {
                 range "1..2";
               }
               default "2";
               description
                 "MLD version.";
             }
             uses per-interface-config-attributes;
             leaf sender-source-address {
               type inet:ipv6-address-no-zone;
               description
                 "The sender source address of an
                  MLD membership report message or leave message.";
             }
             list group {
               key "group-address";
               config false;
               description
                 "List of the multicast groups in the membership
                  database built on this upstream interface.";
               leaf group-address {
                 type rt-types:ipv6-multicast-group-address;
                 description
                   "Multicast group address.";
               }
               uses state-group-attributes;
               list source {
                 key "source-address";
                 description
                   "Multicast source information
                    for the multicast group.";
                 leaf source-address {
                   type inet:ipv6-address-no-zone;
                   description
                     "Multicast source address.";
                 }
                 leaf up-time {
                   type uint32;
                   units "seconds";
                   description
                     "The elapsed time for (S,G) or (*,G).";
                 }
                 list downstream-interface {
                   key "name";
                   description
                     "List of downstream interfaces.";
                   leaf name {
                     type if:interface-ref;
                     description
                       "Downstream interfaces
                        for each upstream interface.";
                   }
                 }
               } // list source
             } // list group
           } // interface
         } // interfaces
       }
     }
   }
   <CODE ENDS>

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

   Under /rt:routing/rt:control-plane-protocols/rt:control-plane-
   protocol:/ igmp-mld-proxy:igmp-proxy:

   igmp-mld-proxy:interfaces
      This subtree specifies the interface list for an IGMP Proxy.
      Modifying the configuration may cause the IGMP Proxy interface to
      be deleted or changed.

   igmp-mld-proxy:interfaces/interface
      This subtree specifies the configuration for the IGMP Proxy
      attributes at the interface level.  Modifying the configuration
      may cause the IGMP Proxy to be deleted or changed on a specific
      interface.

   Under /rt:routing/rt:control-plane-protocols/rt:control-plane-
   protocol:/ igmp-mld-proxy:mld-proxy:

   igmp-mld-proxy:interfaces
      This subtree specifies the interface list for an MLD Proxy.
      Modifying the configuration may cause the MLD Proxy interface to
      be deleted or changed.

   igmp-mld-proxy:interfaces/interface
      This subtree specifies the configuration for the MLD Proxy
      attributes at the interface level.  Modifying the configuration
      may cause the MLD Proxy to be deleted or changed on a specific
      interface.

   Unauthorized access to any data nodes in these subtrees can adversely
   affect the IGMP/MLD Proxy subsystem of both the local device and the
   network.  This may lead to network malfunctions, delivery of packets
   to inappropriate destinations, and other problems.

   Some of the readable data nodes in this YANG module may be considered
   sensitive or vulnerable in some network environments.  It is thus
   important to control read access (e.g., via get, get-config, or
   notification) to these data nodes.  These are the subtrees and data
   nodes and their sensitivity/vulnerability:

   Under
   /rt:routing/rt:control-plane-protocols/rt:control-plane-protocol:/

   igmp-mld-proxy:igmp-proxy
   igmp-mld-proxy:mld-proxy

   Unauthorized access to any data nodes in these subtrees can disclose
   operational state information about the IGMP/MLD Proxy on this
   device.  Group information or source information may expose multicast
   group memberships.

6.  IANA Considerations

6.1.  IETF XML Registry

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

   URI:  urn:ietf:params:xml:ns:yang:ietf-igmp-mld-proxy
   Registrant Contact:  The IESG.
   XML:  N/A; the requested URI is an XML namespace.

6.2.  YANG Module Names Registry

   This document registers the following YANG module in the "YANG Module
   Names" registry [RFC6020]:

   Name:  ietf-igmp-mld-proxy
   Namespace:  urn:ietf:params:xml:ns:yang:ietf-igmp-mld-proxy
   Prefix:  igmp-mld-proxy
   Reference:  RFC 9398

7.  References

7.1.  Normative References

   [RFC3376]  Cain, B., Deering, S., Kouvelas, I., Fenner, B., and A.
              Thyagarajan, "Internet Group Management Protocol, Version
              3", RFC 3376, DOI 10.17487/RFC3376, October 2002,
              <https://www.rfc-editor.org/info/rfc3376>.

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

   [RFC3810]  Vida, R., Ed. and L. Costa, Ed., "Multicast Listener
              Discovery Version 2 (MLDv2) for IPv6", RFC 3810,
              DOI 10.17487/RFC3810, June 2004,
              <https://www.rfc-editor.org/info/rfc3810>.

   [RFC4605]  Fenner, B., He, H., Haberman, B., and H. Sandick,
              "Internet Group Management Protocol (IGMP) / Multicast
              Listener Discovery (MLD)-Based Multicast Forwarding
              ("IGMP/MLD Proxying")", RFC 4605, DOI 10.17487/RFC4605,
              August 2006, <https://www.rfc-editor.org/info/rfc4605>.

   [RFC6020]  Bjorklund, M., Ed., "YANG - A Data Modeling Language for
              the Network Configuration Protocol (NETCONF)", RFC 6020,
              DOI 10.17487/RFC6020, October 2010,
              <https://www.rfc-editor.org/info/rfc6020>.

   [RFC6241]  Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
              and A. Bierman, Ed., "Network Configuration Protocol
              (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
              <https://www.rfc-editor.org/info/rfc6241>.

   [RFC6242]  Wasserman, M., "Using the NETCONF Protocol over Secure
              Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
              <https://www.rfc-editor.org/info/rfc6242>.

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

   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <https://www.rfc-editor.org/info/rfc7950>.

   [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>.

   [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>.

   [RFC8341]  Bierman, A. and M. Bjorklund, "Network Configuration
              Access Control Model", STD 91, RFC 8341,
              DOI 10.17487/RFC8341, March 2018,
              <https://www.rfc-editor.org/info/rfc8341>.

   [RFC8342]  Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
              and R. Wilton, "Network Management Datastore Architecture
              (NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
              <https://www.rfc-editor.org/info/rfc8342>.

   [RFC8343]  Bjorklund, M., "A YANG Data Model for Interface
              Management", RFC 8343, DOI 10.17487/RFC8343, March 2018,
              <https://www.rfc-editor.org/info/rfc8343>.

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

   [RFC8446]  Rescorla, E., "The Transport Layer Security (TLS) Protocol
              Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
              <https://www.rfc-editor.org/info/rfc8446>.

   [RFC8652]  Liu, X., Guo, F., Sivakumar, M., McAllister, P., and A.
              Peter, "A YANG Data Model for the Internet Group
              Management Protocol (IGMP) and Multicast Listener
              Discovery (MLD)", RFC 8652, DOI 10.17487/RFC8652, November
              2019, <https://www.rfc-editor.org/info/rfc8652>.

   [RFC9128]  Liu, X., McAllister, P., Peter, A., Sivakumar, M., Liu,
              Y., and F. Hu, "YANG Data Model for Protocol Independent
              Multicast (PIM)", RFC 9128, DOI 10.17487/RFC9128, October
              2022, <https://www.rfc-editor.org/info/rfc9128>.

7.2.  Informative References

   [RFC7761]  Fenner, B., Handley, M., Holbrook, H., Kouvelas, I.,
              Parekh, R., Zhang, Z., and L. Zheng, "Protocol Independent
              Multicast - Sparse Mode (PIM-SM): Protocol Specification
              (Revised)", STD 83, RFC 7761, DOI 10.17487/RFC7761, March
              2016, <https://www.rfc-editor.org/info/rfc7761>.

   [RFC7951]  Lhotka, L., "JSON Encoding of Data Modeled with YANG",
              RFC 7951, DOI 10.17487/RFC7951, August 2016,
              <https://www.rfc-editor.org/info/rfc7951>.

   [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>.

Appendix A.  Data Tree Example

   This section contains an example for the IGMP Proxy, shown in JSON
   encoding [RFC7951] and containing both configuration and state data.
   In the example, the IGMP Proxy is enabled on interface eth1/1.

   The ability to enable IGMP on eth1/2 and eth1/3 is also needed.  The
   configuration details are omitted here because this document is
   focused on IGMP/MLD Proxies.

              +-----------+
              +  Source   +
              +-----+-----+
                    |
   -----------------+----------------------------
                    |eth1/1
                +---+----+
                +  R1    +
                +-+----+-+
           eth1/2 |     \ eth1/3
                  |      \
                  |       \
                  |        \
   ---------------+---------+--------------------
                  |          \
                  |           \
        +---------+--+     +---+--------+
        + Receiver 1 +     + Receiver 2 +
        +------------+     +------------+

   The configuration data for R1 in the above figure could be as
   follows:

   {
       "ietf-interfaces:interfaces": {
         "interface": [
           {
             "name": "eth1/1",
             "type": "iana-if-type:ipForward",
             "ietf-ip:ipv4": {
               "address": [
                 {
                   "ip": "203.0.113.1",
                   "prefix-length": 24
                 }
               ]
             }
           }
         ]
       },
      "ietf-routing:routing": {
         "control-plane-protocols": {
           "control-plane-protocol": [
             {
               "type": "ietf-igmp-mld-proxy:igmp-proxy",
               "name": "proxy1",
               "ietf-igmp-mld-proxy:igmp-proxy": {
                 "interfaces": {
                   "interface": [
                     {
                       "name": "eth1/1",
                       "igmp-version": 3,
                       "enabled": true
                     }
                   ]
                 }
               }
             }
           ]
         }
       }
     }

   The corresponding operational state data for R1 could be as follows:

   {
       "ietf-interfaces:interfaces": {
         "interface": [
           {
             "name": "eth1/1",
             "type": "iana-if-type:ipForward",
             "admin-status": "up",
             "oper-status": "up",
             "if-index": 25678136,
             "statistics": {
               "discontinuity-time": "2021-05-23T10:34:56-06:00"
             },
             "ietf-ip:ipv4": {
               "address": [
                 {
                   "ip": "203.0.113.1",
                   "prefix-length": 24
                 }
               ]
             }
           }
         ]
       },
      "ietf-routing:routing": {
         "control-plane-protocols": {
           "control-plane-protocol": [
             {
               "type": "ietf-igmp-mld-proxy:igmp-proxy",
               "name": "proxy1",
               "ietf-igmp-mld-proxy:igmp-proxy": {
                 "interfaces": {
                   "interface": [
                     {
                       "name": "eth1/1",
                       "igmp-version": 3,
                       "enabled": true,
                       "group": [
                         {
                           "group-address": "233.252.0.23",
                           "filter-mode": "include",
                           "source": [
                             {
                               "source-address": "192.0.2.1",
                               "downstream-interface": [
                                 {
                                   "name": "eth1/2"
                                 },
                                 {
                                   "name": "eth1/3"
                                 }
                               ]
                             }
                           ]
                         }
                       ]
                     }
                   ]
                 }
               }
             }
           ]
         }
       }
     }

Authors' Addresses

   Hongji Zhao
   Ericsson (China) Communications Company Ltd.
   Ericsson Tower, No. 5 Lize East Street
   Beijing
   100102
   China
   Email: hongji.zhao@ericsson.com


   Xufeng Liu
   Alef Edge
   United States of America
   Email: xufeng.liu.ietf@gmail.com


   Yisong Liu
   China Mobile
   China
   Email: liuyisong@chinamobile.com


   Mani Panchanathan
   Cisco Systems, Inc.
   3625 Cisco Way
   San Jose, CA
   United States of America
   Email: mapancha@cisco.com


   Mahesh Sivakumar
   Juniper Networks
   1133 Innovation Way
   Sunnyvale, CA
   United States of America
   Email: sivakumar.mahesh@gmail.com
