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<rfc category="std"  docName="draft-ietf-mboned-multicast-yang-model-16"
     ipr="trust200902">
  <!-- ***** FRONT MATTER ***** -->
  <front>
    <title abbrev="Multicast YANG Data Model">A YANG Data Model for Multicast Services</title>

    <author fullname="Zheng Zhang" initials="Z" surname="Zhang">
      <organization>ZTE Corporation</organization>
      <address>
        <postal>
          <street></street>
          <city></city>
          <region></region>
          <code></code>
          <country>China</country>
        </postal>
        <email>zhang.zheng@zte.com.cn</email>
      </address>
    </author>

     <author fullname="Cui(Linda) Wang" initials="C" surname="Wang">
      <organization>Individual</organization>
      <address>
        <postal>
          <street></street>
          <city></city>
          <region></region>
          <code></code>
          <country>Australia</country>
        </postal>
        <email>lindawangjoy@gmail.com</email>
      </address>
    </author>

     <author fullname="Ying Cheng" initials="Y" surname="Cheng">
      <organization>China Unicom</organization>
      <address>
        <postal>
          <street></street>
          <city>Beijing</city>
          <region></region>
          <code></code>
          <country>China</country>
        </postal>
        <email>chengying10@chinaunicom.cn</email>
      </address>
    </author>

    <author fullname="Xufeng Liu" initials="X" surname="Liu">
      <organization>Alef Edge</organization>
      <address>
        <postal>
          <street></street>
          <city></city>
          <code></code>
          <country></country>
        </postal>
        <email>xufeng.liu.ietf@gmail.com</email>
      </address>
    </author>

     <author fullname="Mahesh Sivakumar" initials="M" surname="Sivakumar">
      <organization>Juniper networks</organization>
      <address>
        <postal>
          <street>1133 Innovation Way</street>
          <city>Sunnyvale, CALIFORNIA 94089</city>
          <region></region>
          <code></code>
          <country>USA</country>
        </postal>
        <email>sivakumar.mahesh@gmail.com</email>
      </address>
    </author>

    <date year="2026"/>
    <area>Ops</area>
    <workgroup>MBONED WG</workgroup>
    <keyword>MULTICAST, YANG, MODEL</keyword>
    <abstract>
     <t>This document provides a generic multicast YANG data model that shows the relevant technologies or protocols used by multicast flows.
        It provides a management view for network administrators to obtain information about multicast services.</t>
    </abstract>
  </front>

  <!-- ***** MIDDLE MATTER ***** -->

  <middle>

  <section title="Introduction">
    <t>Currently, there are many multicast protocol YANG models, such as PIM (Protocol Independent Multicast), MLD (Multicast Listener Discovery),
    and BIER (Bit Index Explicit Replication) and so on.
     But all these models are distributed in different working groups as separate files and focus on the protocol itself.
     Furthermore, they cannot describe a high-level multicast service required by network operators. </t>

    <t>This document provides a general and all-round multicast model, which shows the relevant technologies or protocols used by multicast flows.
    It provides a management view for network administrators to obtain information about multicast services.</t>

    <t>This document does not define any specific protocol model, instead,
     it depends on many existing multicast protocol models and relates several multicast information together to fulfill multicast service. </t>

      <t>This document defines one YANG 1.1 <xref target="RFC7950"/> data model for the management of multicast service.
    This model can be used along with other multicast
    YANG models such as PIM <xref target="RFC9128"/>, which are not covered in this document.
      </t>

    <section title="Terminology">
    <t>The terminology for describing YANG data models is found in
    <xref target="RFC6020"/> and <xref target="RFC7950"/>, including:</t>
    <t>
  <list style="symbols">
    <t>data model</t>
    <t>data node</t>
    <t>identity</t>
    <t>module</t>
    </list>
    </t>

    <t>The following abbreviations are used in this document and the defined
    model:</t>
  <t>BIER: Bit Index Explicit Replication <xref target="RFC8279"/>.</t>
  <t>BIER-TE: Traffic Engineering for Bit Index Explicit Replication <xref target="RFC9262"/>.</t>
  <t>MLD: Multicast Listener Discovery <xref target="I-D.ietf-bier-mld"/>.</t>
  <t>MLDP: Label Distribution Protocol Extensions for Point-to-Multipoint and Multipoint-to-Multipoint Label Switched Paths <xref target="RFC6388"/>.</t>
  <t>MVPN: Multicast in MPLS/BGP IP VPNs <xref target="RFC6513"/>.</t>
  <t>P2MP-TE: Point-to-Multipoint Traffic Engineering <xref target="RFC4875"/>.</t>
  <t>PIM: Protocol Independent Multicast <xref target="RFC7761"/>.</t>
  <t>SR-P2MP: Segment Routing Point-to-Multipoint <xref target="I-D.ietf-pim-sr-p2mp-policy"/>.</t>
    </section>

    <section title="Conventions Used in This Document">
    <t>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 <xref target="RFC2119"/> <xref target="RFC8174"/>
   when, and only when, they appear in all capitals, as shown here.</t>
    </section>

    <section title="Tree Diagrams">
    <t>Tree diagrams used in this document follow the notation defined in
       <xref target="RFC8340"/>.</t>
    </section>

    <section title="Prefixes in Data Node Names">
    <t>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.</t>

  <texttable anchor="TABLE_1" title="">

     <ttcol align="left">Prefix</ttcol>
     <ttcol align="left">YANG module</ttcol>
     <ttcol align="left">Reference</ttcol>

     <c>inet</c>
     <c>ietf-inet-types</c>
     <c><xref target="RFC9911"/></c>

     <c>rt-types</c>
     <c>ietf-routing-types</c>
     <c><xref target="RFC8294"/></c>

    </texttable>
   </section>
  </section>

  <section title="Design of the Data Model">
 
   <section title="Scope of Model">
    <t>This model can be used to configure and manage the multicast service.
   The operational state data can be retrieved by this
   model.  The subscription and push mechanism defined in <xref target="RFC8639"/> and
   <xref target="RFC8641"/> can be implemented by the user to subscribe to
   notifications on the data nodes in this model.</t>

    <t>The model contains all the basic configuration parameters to configure the multicast service.
   Depending on the implementation choices, some systems
   may not allow some of the advanced parameters to be configurable.
   The occasionally implemented parameters are modeled as optional
   features in this model.  This model can be extended, and it has been
   structured in a way that such extensions can be conveniently made.</t>

  <section title="Usage of Multicast Model">
    <t>This multicast YANG data model is mainly used by the management tools run by the network operators,
     in order to manage, monitor and debug the network resources that are used to deliver multicast service.
     This model is used for gathering data from the network as well. </t>


    <figure anchor="fig1" title="Usage of Multicast Model">
           <artwork><![CDATA[

               +------------------------+
               |    Multicast Model     |
               +------------------------+
                 |        |          |
                 |        |          |
                 |  +---------+  +----------+
                 |  | EMS/NMS |  |Controller|
                 |  +---------+  +----------+
                 |        |          |
                 |        |          |
        +------------------------------------------------+
        |               Network Element1.....N           |
        +------------------------------------------------+

          ]]></artwork></figure>

    <t> <xref target="fig1"/> illustrates example use cases for this multicast model.
     Network operators can use this model in a controller which is responsible to implement specific multicast
     flows with specific protocols and work with the corresponding
     protocols' model to configure the network elements through NETCONF/RESTCONF/CLI. Or network operators can use this model
     to the EMS (Element Management System)/ NMS (Network Management System) to manage or configure the network elements directly. </t>

    <t>On the other hand, when the network
     elements detect failure or some other changes, the network devices can send the affected multicast flows and the associated
     signaling/ transport information to the controller. Then the controller/ EMS/NMS can respond immediately due to the
     failure. Such as the changing of the failure signaling protocol to another one, as well as transport protocol.
     
	 Network nodes can enable appropriate signaling and transport technologies for multicast flows based on the YANG model configuration
	 obtained from the controller.
	 For example, the network ingress node of a multicast flow
	 can specify its signaling protocol as MVPN and its network transport technology as BIER based on the obtained YANG model configuration. 
	 If the network ingress node does not support BIER technology, it will send a notification to the controller so that the controller 
	 can respond and adjust accordingly. 
	 Different multicast flow can use the same or different signaling and transport protocols. 
	 For the same multicast traffic, different signaling and transport technologies can also be used due to different management needs.</t>

     <t>The Route Distinguisher, source-address and group-address of L3 multicast flow are the multicast flow keys.
     For example, when the group-address is set, and the source-address is set to * or a specific value, this is (*,G) or (S,G) analogous.
     In addition to the source-address and group-address, when vpn-rd is also set, this is MVPN use case.
	 For non-VPN multicast, according to the definition in section 2.1 of RFC7716, when all RDs are set to zero,
	 it indicates non-VPN multicast, i.e., Global Table Multicast.</t>

    <t>
    <list style="symbols">

     <t>When the ingress node of a multicast flow receives the configured YANG model, 
	 it can announce the multicast flow using the signaling protocol specified, such as MVPN. 
	 Egress nodes with receiving needs will initiate a join signaling message to the ingress node.</t>

     <t>When a multicast flow's egress node receives a configured YANG model, if a signaling protocol is specified, 
	 it can initiate joining using the specified signaling protocol based on its calculated upstream multicast next hop.</t>
	 
	 <t>When a transport protocol type is configured, the specified transport protocol type may be added to the signaling. 
	 For protocols that can use virtual topology for forwarding via IGP routing, such as BIER, MLDP, and PIM, 
	 when topology and flex algo number are configured, traffic will be forwarded according to the corresponding logical topology.</t>

     <t>More than one ingress node for a multicast flow can be set in the model.
     In this situation, two or more ingress nodes are used for a multicast flow forwarding, the ingress routers can be backup for each other.
     More information can be found in <xref target="I-D.ietf-mboned-redundant-ingress-failover"/>.</t>

     <t>Network ingress or egress nodes can feed back the YANG model to the controller 
	 so that network administrators can check the consistency of configuration and effectiveness.
     When the received information is inconsistent with expectations,
     for example, a multicast flow should be forwarded through BIER transmission,
     but the received information shows that the multicast flow is forwarded by PIM,
     there may be some management inconsistencies.</t>
     </list>
     </t>
    </section>
   </section>

   <section title="Specification">
   <t>This model imports and augments ietf-routing YANG model defined in
   <xref target="RFC8349"/>.  The container "multicast-service" is the top-level container in this
   data model.  The container is expected to enable multicast service
   functionality.</t>

   <t>The YANG data model defined in this document conforms to the Network
   Management Datastore Architecture (NMDA) <xref target="RFC8342"/>.  The operational
   state data is combined with the associated configuration data in the
   same hierarchy <xref target="RFC9907"/>.</t>
   </section>

   <section title="Overview">
    <t>Tree diagrams used in this document follow the notation defined in <xref target="RFC8340"/>.</t>
	
	<t>The model as a whole consists of multicast flow key-value pairs, upstream and downstream information. 
	Upstream information includes the multicast flow's ingress node in the multicast domain 
	and the dynamic signaling protocols it may use; 
	downstream information includes the multicast flow's egress node in the multicast domain, 
	the dynamic signaling protocols it may use, and the transport protocols it may use. 
	Here, the multicast domain refers to a management domain, which includes all edge nodes (ingress and egress nodes) 
	and corresponding intermediate nodes.</t>
	
	<figure  align="center">
            <artwork align="center"><![CDATA[
module: ietf-multicast
  +--rw multicast-service
     +--rw multicast-flow* [vpn-rd source-address group-address]
        +--rw vpn-rd            rt-types:route-distinguisher
        +--rw source-address    ip-multicast-source-address
        +--rw group-address     rt-types:ip-multicast-group-address
        +--rw upstream
        |  +--rw neighbor* [neighbor-address]
        |     +--rw neighbor-address    inet:ip-address
        |     +--rw vni-type?           identityref
        |     +--rw signaling?          identityref
        |     +--rw (protocol-type)?
        |        +--:(evpn)
        |        +--:(mld)
        |        +--:(mld-snooping)
        |        +--:(mvpn)
        |        +--:(pim)
        +--rw downstream* [signaling transport]
           +--rw neighbor* [neighbor-address]
           |  +--rw neighbor-address    inet:ip-address
           +--rw signaling               identityref
           +--rw (protocol-type)?
           |  +--:(evpn)
           |  +--:(mld)
           |  +--:(mld-snooping)
           |  +--:(mvpn)
           |  +--:(pim)
           +--rw transport               identityref
           +--rw (transport-tech-type)?
              +--:(bier) {bier}?
              |  +--rw bier* [sub-domain]
              |     +--rw sub-domain         uint16
              |     +--rw tad* [mt-id fa-number data-plane]
              |     |  +--rw mt-id         uint16
              |     |  +--rw fa-number     uint8
              |     |  +--rw data-plane    uint8
              |     +--rw bitstringlength?   uint16
              |     +--rw bier-encap-type?   identityref
              +--:(bier-te) {bier-te}?
              |  +--rw bitstring* [name]
              |     +--rw name           string
              |     +--rw bier-te-adj* [adj-id]
              |        +--rw adj-id    uint16
              +--:(mldp) {mldp}?
              |  +--rw mt-id?            uint16
              |  +--rw fa-number?        uint8
              +--:(rsvp-te-p2mp) {p2mp-te}?
              |  +--rw tunnel-name?      string
              +--:(pim) {pim}?
              |  +--rw source-address?   ip-multicast-source-address
              |  +--rw group-address
              |  |       rt-types:ip-multicast-group-address
              |  +--rw bidir?            boolean {bidir}?
              |  +--rw tad* [mt-id fa-number data-plane]
              |     +--rw mt-id         uint16
              |     +--rw fa-number     uint8
              |     +--rw data-plane    uint8
              +--:(ir-tunnel) {ir-tunnel}?
              |  +--rw ir-tunnel-type?   uint8
              +--:(sr-p2mp) {sr-p2mp}?
              +--:(native)

  notifications:
    +---n ingress-egress-event
       +--ro event-type?       identityref
       +--ro multicast-flow* [vpn-rd source-address group-address]
          +--ro vpn-rd            rt-types:route-distinguisher
          +--ro source-address    ip-multicast-source-address
          +--ro group-address     rt-types:ip-multicast-group-address
          +--ro upstream
          |  +--ro neighbor-address?   inet:ip-address
          |  +--ro signaling?          identityref
          +--ro downstream* [signaling transport]
             +--ro neighbor-address?   inet:ip-address
             +--ro signaling           identityref
             +--ro transport           identityref
            ]]></artwork>
       <postamble></postamble>
      </figure>
     </section>

    <section title="Multicast YANG data model Configuration">
    <t>This model can work with other protocol data models to provide multicast service.</t>

    <t>Based on the concept of multicast, the model includes upstream and downstream information.
	The content of this model includes multicast service keys, the multicast service signaling,
    the transport protocol information. Multicast keys include the
    features of multicast flow, such as (vpn-rd, multicast source and multicast group) information.</t>
	 
	<t>Multicast flows can be advertised via dynamic protocol signaling. 
	Both ingress and egress nodes can be configured and obtain the dynamic signaling protocol types they use through the model. 
	In certain scenarios, multicast flows can also perform tunnel encapsulation (GRE, VXLAN, etc.) 
	before transport protocol encapsulation; the tunnel encapsulation type is included in the upstream information. 
	Multicast flows can specify transport protocols and can further specify their associated logical topology 
	based on topology and flex algo number; transport protocol information is included in the downstream information.</t>

    <t>When a multicast flow does not need to be advertised via a dynamic signaling protocol, 
	the addresses of all ingress and egress nodes can be directly specified in the model. 
	When a multicast flow is advertised between ingress and egress nodes via a dynamic signaling protocol, 
	it is not necessary to include the addresses of all ingress and egress nodes in the model; 
	only the address of the ingress or egress node needs to be included. 
	When a multicast flow needs to be transmitted via a specified protocol, 
	the downstream information in the model needs to include the transmission protocol information.</t> 
	
	<section title="Example">
    <figure anchor="fig2" title="Example">
           <artwork><![CDATA[
                            +------------+
                            |            +---------------------------+
             +--------------+ Controller |                           |
             |              |            +-----------+               |
             |              +------------+           |               |
             |                                       |               |
             |     +-----------------------------+   |               |
             |     |                             |   |               |
             |     |                      +------+---+--+            |
             |     |                      |Egress router+--+ Receiver|
             |     |                      +------+------+            |
         +---+-----+----+                        |                   |
Source +-|Ingress router|     BIER domain        |                   |
         +---------+----+                        |                   |
                   |                      +------+------+            |
                   |                      |Egress router+--+ Receiver|
                   |                      +------+----+-+            |
                   |                             |    |              |
                   +-----------------------------+    +--------------+
          ]]></artwork></figure>

     <t>In this example, a multicast flow using MVPN with a group address of 233.252.0.10 will be sent from one ingress node 
	 to two egress nodes within this multicast domain via BIER technology.</t>

	 <t>The models sent to both the ingress (upstream) and egress nodes (downstream) will contain key-value information about the flow, 
	 such as the RD and group address. The source address can be set to "*". 
	 The ingress node address is 198.51.100.10. 
	 When the ingress node receives the model, it can identify itself as upstream based on the address and configure its signaling as MVPN.
	 The ingress node with address 198.51.100.10 will then use MVPN signaling to announce the multicast flow information.</t>

     <t>The model sent to the egress nodes (198.51.100.20, 198.51.100.30) will, in addition to containing the multicast flow key, 
	 specify its downstream neighbors address. The egress nodes will recognize themselves as the egress node 
	 based on the downstream neighbor address and can then notify the upstream node of its joining information 
	 for the multicast group via MVPN signaling, specifying that traffic transmission should be via BIERin6. 	 
	 Furthermore, traffic transmission can be performed using a specific virtual topology, 
	 such as a virtual topology built based on the Flex Algo number 200 soft-dataplane.</t>
	 
	 <t>The JSON example in the appendix can be considered a configuration example of this model. 
	 In practical applications, it is not necessary to specify both upstream and downstream information simultaneously; 
	 specifying only upstream or downstream is sufficient for it to function.</t>
	 
	 <t>When there is no dynamic signaling protocol between the ingress and egress nodes, 
	 the configuration YANG model includes all ingress and egress nodes and specifies the use of the BIER transport protocol 
	 in the downstream information.
	 Referring to the JSON example in the appendix, the signaling parameter can be removed from the upstream and downstream information.</t>
	 
     </section>
	
    </section>

    <section title="Multicast YANG data model State">
    <t>Multicast model states are the same with the configuration.
    In most cases, network administrators can use this model to obtain multicast flows and related protocol information
    such as signaling protocols and transport technologies.</t>
    </section>

    <section title="Multicast YANG data model Notification">
    <t>The defined Notifications include the events of ingress or egress nodes. Like ingress node failure,
    signaling/ transport module loading/ unloading. And the potential failure about
    some multicast flows and associated signaling/ transport technologies.</t>
   </section>

  </section>

    <section title="Multicast YANG data Model">
    <t>This module references <xref target="RFC4541"/>, <xref target="RFC4875"/>, <xref target="RFC4915"/>,
  <xref target="RFC5015"/>, <xref target="RFC5120"/>,
  <xref target="RFC6388"/>, <xref target="RFC6513"/>, <xref target="RFC6514"/>,
  <xref target="RFC7348"/>, <xref target="RFC7432"/>, <xref target="RFC7637"/>, <xref target="RFC7716"/>,
  <xref target="RFC7761"/>, <xref target="RFC7988"/>,
  <xref target="RFC8174"/>, <xref target="RFC8279"/>, <xref target="RFC8294"/>, <xref target="RFC8296"/>,
  <xref target="RFC8556"/>, <xref target="RFC8926"/>,
  <xref target="RFC9179"/>, <xref target="RFC9262"/>, <xref target="RFC9350"/>, <xref target="RFC9502"/>,
  <xref target="RFC9524"/>, <xref target="RFC9572"/>, <xref target="RFC9624"/>, <xref target="RFC9658"/>,
  <xref target="RFC9911"/>,
  <xref target="I-D.ietf-bier-mld"/>,
  <xref target="I-D.ietf-bier-bierin6"/>,
  <xref target="I-D.ietf-bier-pim-signaling"/>,
  <xref target="I-D.ietf-lsr-flex-soft-dataplane"/>,
  <xref target="I-D.ietf-pim-sr-p2mp-policy"/>,
  <xref target="I-D.ietf-pim-flex-algo"/>.
  </t>

     <figure  align="center">
            <artwork align="center"><![CDATA[
<CODE BEGINS> file "ietf-multicast@2026-04-12.yang"
module ietf-multicast {
  yang-version 1.1;
  namespace "urn:ietf:params:xml:ns:yang:ietf-multicast";
  prefix ietf-multicast;

  import ietf-inet-types {
    prefix inet;
    reference
      "RFC 9911: Common YANG Data Types";
  }
  import ietf-routing-types {
    prefix rt-types;
    reference
      "RFC 8294: Common YANG Data Types for the Routing Area";
  }

  organization
    " IETF MBONED (MBONE Deployment) Working Group";
  contact
    "WG Web:   https://datatracker.ietf.org/wg/mboned/
     WG List:  <mailto:mboned@ietf.org>

     Editor:   Zheng Zhang
               <mailto:zhang.zheng@zte.com.cn>
     Editor:   Cui Wang
               <mailto:lindawangjoy@gmail.com>
     Editor:   Ying Cheng
               <mailto:chengying10@chinaunicom.cn>
     Editor:   Xufeng Liu
               <mailto:xufeng.liu.ietf@gmail.com>
     Editor:   Mahesh Sivakumar
               <mailto:sivakumar.mahesh@gmail.com>
    ";

  // RFC Ed.: replace XXXX with actual RFC number and remove
  // this note

  description
    "The module defines the YANG definitions for multicast service
     management. This model can be used to send multicast flow
     information to or retrieve multicast flow information from
     devices, including upstream and downstream node information,
     possible signaling protocols, and the multicast transmission
     protocol that actually carries the multicast flow.

     Copyright (c) 2026 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
     (https://www.rfc-editor.org/info/rfcXXXX); 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 2026-04-12 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for multicast service management
       YANG.";
  }

  /*
   *feature
   */

  feature bier {
    description
      "Cooperation with BIER technology.";
    reference
      "RFC 8279: Multicast Using Bit Index Explicit Replication
         (BIER)";
  }

  feature bier-te {
    description
      "Cooperation with BIER-TE technology.";
    reference
      "RFC 9262: Tree Engineering for Bit Index Explicit Replication
         (BIER-TE)";
  }

  feature sr-p2mp {
    description
      "Cooperation with multipoint Segment Routing replication
       technology.";
    reference
      "RFC 9524: Segment Routing Replication for Multipoint
         Service Delivery";
  }

  feature ir-tunnel {
    description
      "Cooperation with Ingress Replication tunnel technology.";
    reference
      "RFC 7988: Ingress Replication Tunnels in Multicast VPN";
  }

  feature mldp {
    description
      "Cooperation with MLDP technology.";
    reference
      "RFC 6388: Label Distribution Protocol Extensions
         for Point-to-Multipoint and Multipoint-to-Multipoint
         Label Switched Paths";
  }

  feature p2mp-te {
    description
      "Cooperation with RSVP TE P2MP technology.";
    reference
      "RFC 4875: Extensions to Resource Reservation Protocol -
        Traffic Engineering (RSVP-TE) for Point-to-Multipoint TE
        Label Switched Paths (LSPs)";
  }

  feature pim {
    description
      "Cooperation with PIM technology.";
    reference
      "RFC 7761: Protocol Independent Multicast - Sparse Mode
       (PIM-SM): Protocol Specification (Revised)";
  }

  feature bidir {
    description
      "Cooperation with BIDIR-PIM technology.";
    reference
      "RFC 5015: Bidirectional Protocol Independent Multicast
       (BIDIR-PIM)";
  }

  /*
   *typedef
   */

  typedef ip-multicast-source-address {
    type union {
      type enumeration {
        enum * {
          description
            "Any source address.";
        }
      }
      type inet:ipv4-address;
      type inet:ipv6-address;
    }
    description
      "Multicast source IP address type.";
  }

  /*
   * Identities
   */

  identity dynamic-signaling-type {
    description
      "Base identity for the dynamic signaling type of multicast
       service technology.";
  }

  identity transport-type {
    description
      "Identity for the multicast transport technology.";
  }

  identity tunnel-encap-type {
    description
      "Base identity for the type of multicast flow tunnel
       encapsulation.";
  }

  identity tunnel-encap-vxlan {
    base tunnel-encap-type;
    description
      "The VXLAN encapsulation is used for flow encapsulation.";
    reference
      "RFC 7348: Virtual eXtensible Local Area Network (VXLAN):
        A Framework for Overlaying Virtualized Layer 2 Networks
        over Layer 3 Networks";
  }

  identity tunnel-encap-nvgre {
    base tunnel-encap-type;
    description
      "The NVGRE encapsulation is used for flow encapsulation.";
    reference
      "RFC 7637: NVGRE: Network Virtualization Using Generic
        Routing Encapsulation";
  }

  identity tunnel-encap-geneve {
    base tunnel-encap-type;
    description
      "The GENEVE encapsulation is used for flow encapsulation.";
    reference
      "RFC 8926: Geneve: Generic Network Virtualization
        Encapsulation";
  }
  
  identity bier-encapsulation{
    description
      "Base identity for BIER encapsulation.";
  }
  identity bier-encap-mpls {
    base bier-encapsulation;
    description
      "This identity represents MPLS encapsulation for bier.";
  }
  identity bier-encap-ipv6 {
    base bier-encapsulation;
    description
      "This identity represents ipv6 encapsulation for bier.";
  }
  identity bier-encap-ethernet {
    base bier-encapsulation;
    description
      "This identity represents ethernet encapsulation for bier.";
  }

  identity signaling-pim {
    base dynamic-signaling-type;
    description
      "Using PIM as multicast service signaling technology.
       This signaling protocol needs to be used in conjunction 
       with the transport protocol set to BIER.";
    reference
      "I-D.ietf-bier-pim-signaling: PIM Signaling Through BIER
        Core";
  }

  identity mld {
    base dynamic-signaling-type;
    description
      "Using MLD as multicast service signaling technology.
       This signaling protocol needs to be used in conjunction 
       with the transport protocol set to BIER.";
    reference
      "I-D.ietf-bier-mld: BIER Ingress Multicast Flow Overlay
        using Multicast Listener Discovery Protocols";
  }

  identity mld-snooping {
    base dynamic-signaling-type;
    description
      "Using MLD-snooping as multicast service signaling
       technology.";
    reference
      "RFC 4541: Considerations for Internet Group Management
        Protocol (IGMP) and Multicast Listener
        Discovery (MLD) Snooping Switches";
  }

  identity evpn {
    base dynamic-signaling-type;
    description
      "Using EVPN as multicast service signaling technology.";
    reference
      "RFC 7432: BGP MPLS-Based Ethernet VPN
       RFC 9572: Updates on EVPN BUM Procedures
       RFC 9624: EVPN Broadcast, Unknown Unicast, or Multicast
        (BUM) Using Bit Index Explicit Replication (BIER)";
  }

  identity mvpn {
    base dynamic-signaling-type;
    description
      "Using MVPN as multicast service signaling technology.";
    reference
      "RFC 6513: Multicast in MPLS/BGP IP VPNs
       RFC 7716: Global Table Multicast with BGP Multicast VPN
        (BGP-MVPN) Procedures
       RFC 8556: Multicast VPN Using Bit Index Explicit
        Replication (BIER)";
  }

  identity bier {
    base transport-type;
    description
      "Using BIER as multicast transport technology.";
    reference
      "RFC 8279: Multicast Using Bit Index Explicit Replication
        (BIER)";
  }

  identity bier-te {
    base transport-type;
    description
      "Using BIER-TE as multicast transport technology.";
    reference
      "RFC 9262: Traffic Engineering for Bit Index Explicit
        Replication (BIER-TE)";
  }

  identity mldp {
    base transport-type;
    description
      "Using mLDP as multicast transport technology.";
    reference
      "RFC 6388: Label Distribution Protocol Extensions
        for Point-to-Multipoint and Multipoint-to-Multipoint
        Label Switched Paths";
  }

  identity rsvp-te-p2mp {
    base transport-type;
    description
      "Using P2MP TE as multicast transport technology.";
    reference
      "RFC 4875: Extensions to Resource Reservation Protocol
        - Traffic Engineering (RSVP-TE) for Point-to-Multipoint
        TE Label Switched Paths (LSPs)";
  }

  identity sr-p2mp {
    base transport-type;
    description
      "Using Segment Routing  as multicast transport technology.";
    reference
      "I-D.ietf-pim-sr-p2mp-policy:
         Segment Routing Point-to-Multipoint Policy";
  }

  identity pim {
    base transport-type;
    description
      "Using PIM as multicast transport technology.";
    reference
      "RFC 7761: Protocol Independent Multicast - Sparse Mode
        (PIM-SM): Protocol Specification (Revised)";
  }

  identity bidir {
    base transport-type;
    description
      "Using BIDIR-PIM as multicast transport technology.";
    reference
      "RFC 5015: Bidirectional Protocol Independent Multicast
        (BIDIR-PIM)";
  }

  identity event-type {
    description
      "The events of the multicast service.";
  }

  identity service-up {
    base event-type;
    description
      "The multicast service works.";
  }

  identity service-down {
    base event-type;
    description
      "There is something wrong with upstream or downstream node,
       and node can't work properlay.";
  }

  identity protocol-enabled {
    base event-type;
    description
      "The protocol that is used for multicast flows have been
       enabled.";
  }

  identity protocol-disabled {
    base event-type;
    description
      "The protocol that is used by multicast flows have been
       disabled.";
  }

  grouping general-multicast-key {
    description
      "The general multicast keys. They are used to differentiate
       multicast service.";
    leaf vpn-rd {
      type rt-types:route-distinguisher;
      description
        "A Route Distinguisher is used to differentiate
         routes from different MVPNs.
         When the value is set to 0, it indicates that it is 
         Global Table Multicast as described in RFC7716.";
      reference
        "RFC 8294: Common YANG Data Types for the Routing Area
         RFC 6513: Multicast in MPLS/BGP IP VPNs
         RFC 7716: Global Table Multicast with BGP Multicast VPN
           (BGP-MVPN) Procedures";
    }
    leaf source-address {
      type ip-multicast-source-address;
      description
        "The IP source address of the multicast flow. The
         value set to * means that the receiver interests
         in all source that relevant to one given group.";
    }
    leaf group-address {
      type rt-types:ip-multicast-group-address;
      mandatory true;
      description
        "The IP group address of multicast flow. This
         type represents a version-neutral IP multicast group
         address. The format of the textual representation
         implies the IP version.";
      reference
        "RFC 8294: Common YANG Data Types for the Routing Area";
    }
  }

  // multicast-key

  grouping bier-key {
    description
      "The key parameters set for BIER/BIER TE forwarding.";
    reference
      "RFC 8279: Multicast Using Bit Index Explicit Replication
        (BIER).";
    leaf sub-domain {
      type uint16;
      description
        "The subdomain ID that the multicast flow belongs to.";
    }
    list tad {
      key "mt-id fa-number data-plane";
      description
        "The associated Multi-Topology ID, Flex Algo number and
         data plane type.";
      leaf mt-id {
        type uint16;
        description
          "The multi-topology ID that the multicast flow belongs
           to.";
        reference
          "RFC 4915: Multi-Topology (MT) Routing in OSPF
           RFC 5120: M-ISIS: Multi Topology (MT) Routing in
             Intermediate System to Intermediate Systems (IS-ISs)";
      }
      leaf fa-number {
        type uint8;
        description
          "Flex-algo number, value between 128 and 255 inclusive.";
        reference
          "RFC 9350: IGP Flexible Algorithm";
      }
      leaf data-plane {
        type uint8;
        description
          "Data plane type used for prefix calculation.";
        reference
          "RFC 9502: IGP Flexible Algorithm in IP Networks
           I-D.ietf-lsr-flex-soft-dataplane: IGP Flex Soft
            Dataplane";
      }
    }
    leaf bitstringlength {
      type uint16;
      description
        "The bitstringlength used by BIER forwarding.";
    }
    leaf bier-encap-type {
      type identityref {
        base bier-encapsulation;
      }
      description
        "The BIER encapsulation that can be used in either MPLS
         networks or non-MPLS networks.";
    }
  }

  grouping transport-tech {
    description
      "The transport technology selected for the multicast service.
       For one specific multicast flow.
       The same multicast flow may be forwarded using multiple
       transport technologies as needed for management purposes.";
    leaf transport {
      type identityref {
        base transport-type;
      }
      description
        "The type of transport technology";
    }
    choice transport-tech-type {
      description
        "The type of transport technology";
      case bier {
        if-feature "bier";
        list bier {
          key "sub-domain";
          description
            "Using BIER as the transport technology.
             The BIER technology is introduced in RFC8279.";
          reference
            "RFC 8296: Encapsulation for Bit Index Explicit
               Replication (BIER) in MPLS and Non-MPLS Networks";
          uses bier-key;
        }
      }
      case bier-te {
        if-feature "bier-te";
        description
          "Using BIER-TE as the transport technology.
           The BIER-TE technology is introduced in RFC9262.";
        reference
          "RFC 9262: Tree Engineering for Bit Index Explicit
             Replication (BIER-TE)";
        list bitstring {
          key "name";
          leaf name {
            type string;
            description
              "The name of the bitstring";
          }
          list bier-te-adj {
            key "adj-id";
            leaf adj-id {
              type uint16;
              description
                "The link adjacency ID used for BIER TE
                 forwarding.";
            }
            description
              "The adjacencies ID used for BIER TE bitstring
               encapsulation.";
          }
          description
            "The bitstring name and detail used for BIER TE
             forwarding encapsulation. One or more bitstring
             can be used for backup path.";
        }
      }
      case mldp {
        if-feature "mldp";
        description
          "Using MLDP as the transport technology.";
        reference
          "RFC 6388: Label Distribution Protocol Extensions
            for Point-to-Multipoint and Multipoint-to-Multipoint
            Label Switched Paths
           RFC 9658:
            Multipoint LDP Extensions for Multi-Topology Routing";
        leaf mt-id {
          type uint16;
          description
            "The multi-topology ID that the multicast flow
             belongs to.";
          reference
            "RFC 4915: Multi-Topology (MT) Routing in OSPF
             RFC 5120: M-ISIS: Multi Topology (MT) Routing in
             Intermediate System to Intermediate Systems (IS-ISs)";
        }
        leaf fa-number {
          type uint8;
          description
            "Flex-algo number, value between 128 and 255
             inclusive.";
          reference
            "RFC 9350: IGP Flexible Algorithm";
        }
      }
      case rsvp-te-p2mp {
        if-feature "p2mp-te";
        description
          "Using RSVP TE P2MP as the transport technology.";
        reference
          "RFC 4875: Extensions to Resource Reservation Protocol -
             Traffic Engineering (RSVP-TE) for Point-to-Multipoint
             TE Label Switched Paths (LSPs)";

        leaf tunnel-name {
          type string;
          description
            "The P2MP TE tunnel name.";
        }
      }
      case pim {
        if-feature "pim";
        description
          "Using PIM as the transport technology.
           By setting the corresponding TAD (Multi-Topology ID,
           FA number, and data plane type), constraint-based
           multicast path establishment can be achieved.";
        reference
          "RFC 7761: Protocol Independent Multicast - Sparse Mode
           (PIM-SM): Protocol Specification (Revised)
           I-D: ietf-pim-flex-algo: Multi-Topology in PIM";
        leaf source-address {
          type ip-multicast-source-address;
          description
            "The IP source address of the multicast flow. The
             value set to * means that the receiver interests
             in all source that relevant to one given group.";
        }
        leaf group-address {
          type rt-types:ip-multicast-group-address;
          mandatory true;
          description
            "The IP group address of multicast flow. This
             type represents a version-neutral IP multicast group
             address. The format of the textual representation
             implies the IP version.";
        }
        leaf bidir {
          if-feature "bidir";
          type boolean;
          description
            "Using BIDIR-PIM as the transport technology.
             When using the bidir technique, only the group address
             needs to be considered.";
          reference
            "RFC 5015: Bidirectional Protocol Independent Multicast
             (BIDIR-PIM)";
        }
        list tad {
          key "mt-id fa-number data-plane";
          description
            "The Multi-Topology ID, Flex Algo number and data plane 
             type are used to construct the logical topology, 
             which enables constraint-based forwarding.";
          leaf mt-id {
            type uint16;
            description
              "The multi-topology ID.";
            reference
              "RFC 4915: Multi-Topology (MT) Routing in OSPF
               RFC 5120: M-ISIS: Multi Topology (MT) Routing in
                 Intermediate System to Intermediate Systems
                 (IS-ISs)";
          }
          leaf fa-number {
            type uint8;
            description
              "Flex-algo number, value between 128 and 255
               inclusive.";
            reference
              "RFC 9350: IGP Flexible Algorithm";
          }
          leaf data-plane {
            type uint8;
            description
              "Data plane type used for prefix calculation.";
            reference
              "RFC 9502: IGP Flexible Algorithm in IP Networks
               I-D.ietf-lsr-flex-soft-dataplane:
                 IGP Flex Soft Dataplane";
          }
        }
      }
      case ir-tunnel {
        if-feature "ir-tunnel";
        description
          "Using IR (Ingress Replication) P-tunnel for MVPN as the
           transport technology.";
        reference
          "RFC 7988: Ingress Replication Tunnels in Multicast VPN
           RFC 6514: BGP Encodings and Procedures for Multicast
             in MPLS/BGP IP VPNs";
        leaf ir-tunnel-type {
          type uint8;
          description
            "The tunnel type used by MVPN ingress replication.";
        }
      }
      case sr-p2mp {
        if-feature "sr-p2mp";
        description
          "Using SR P2MP as the transport technology.
           The ingress replication and the SR P2MP
           function should not be used at the same time.";
        reference
          "RFC 9524: Segment Routing Replication for Multipoint
             Service Delivery
           I-D.ietf-pim-sr-p2mp-policy: Segment Routing
             Point-to-Multipoint Policy";
      }
      // sr-p2mp
      case native {
        description
          "When this type is set, it indicates that it is a
           normal multicast and no additional transport
           forwarding is required.";
      }
    }
  }

  // transport
  /*signaling*/
  
  grouping signaling-tech {
    leaf signaling {
      type identityref {
        base dynamic-signaling-type;
      }
      description
        "The type of signaling technology.";
    }
    choice protocol-type {
      description
        "The type of dynamic signaling technology.";
      case evpn {
        description
          "EVPN technology is used for multicast service
           signaling.
           When BIER is used as a transport technology, there is
           specific draft listed below that explain how to
           perform signaling.";
        reference
          "RFC 7432: BGP MPLS-Based Ethernet VPN
           RFC 9624: EVPN Broadcast, Unknown Unicast, or
           Multicast (BUM) Using Bit Index Explicit Replication
           (BIER)";
      }
      case mld {
        description
          "MLD/IGMP can be used as multicast service signaling.
           When BIER is used as a transport technology, there is
           specific draft listed below that explain how to
           perform signaling.";
        reference
          "I-D:ietf-bier-mld: BIER Ingress Multicast Flow Overlay
           using Multicast Listener Discovery Protocols";
      }
      case mld-snooping {
        description
          "MLD/IGMP snooping can be used as multicast service
           signaling.";
        reference
          "RFC 4541:Considerations for Internet Group Management
            Protocol (IGMP) and Multicast Listener Discovery (MLD)
            Snooping Switches";
      }
      case mvpn {
        description
          "MVPN technology is used for multicast service signaling.
           When BIER is used as a transport technology, there is
           specific draft listed below that explain how to
           perform signaling.";
        reference
          "RFC 6513: Multicast in MPLS/BGP IP VPNs
           RFC 7716: Global Table Multicast with BGP Multicast VPN
            (BGP-MVPN) Procedures
           RFC 8556: Multicast VPN Using Bit Index Explicit
            Replication (BIER)";
      }
      case pim {
        description
          "PIM can be used as multicast service signaling.
           When BIER is used as a transport technology, there is
           specific draft listed below that explain how to
           perform signaling.";
        reference
          "RFC 7761: Protocol Independent Multicast - Sparse Mode
            (PIM-SM): Protocol Specification (Revised)
           I-D.ietf-bier-pim-signaling: PIM Signaling Through BIER
            Core";
      }
    }
    description
      "The dynamic signaling protocols.";
  }

  // signaling-tech

  container multicast-service {
    description
      "Multicast service YANG data model. Includes the flow's 
       key value, upstream and downstream neighbors, 
       and related information.";
    list multicast-flow {
      key "vpn-rd source-address group-address";
      description
        "Multicast flow information, including keys, upstream and
         downstream nodes, possible signaling protocols, and
         transport protocols.";
      uses general-multicast-key;
      container upstream {
        description
          "Upstream node neighbor information and the signaling
           protocol used in the multicast flow.";
        list neighbor {
          key "neighbor-address";
          description
            "The IP address of the upstream node for the multicast
             flow. It can be the ingress node for MVPN, EVPN, and
             BIER.
             In MVPN and EVPN, this is the address of the ingress
             PE; in BIER, it is the BFR prefix of the BFIR.
             To achieve redundant ingress node protection, two or
             more ingress nodes can exist.";
          leaf neighbor-address {
            type inet:ip-address;
            description
              "The IP address of the neighbor.";
          }
          leaf vni-type {
            type identityref {
              base tunnel-encap-type;
            }
            description
              "The encapsulated type for the multicast flow.";
          }
          uses signaling-tech;
        }
      }
      // upstream
	  
      list downstream {
        key "signaling transport";
        description
          "Downstream node neighbor information, the signaling
           protocol and transport protocol used by the multicast
           flow. For different downstream neighbor, different
           signaling and transport technology may be used.";

        list neighbor {
          key "neighbor-address";
          description
            "The IP address of the downstream node for the multicast
             flow. It can be the egress node for MVPN, EVPN, and
             BIER.
             In MVPN and EVPN, this is the address of the egress PE;
             in BIER, it is the BFR prefix of the BFER.";
          leaf neighbor-address {
            type inet:ip-address;
            description
              "The IP address of the neighbor.";
          }
        }
        uses signaling-tech;
        uses transport-tech;
      }
      // downstream
    }
    // multicast-flow
  }

  /*Notifications*/

  notification ingress-egress-event {
    leaf event-type {
      type identityref {
        base event-type;
      }
      description
        "The event type.";
    }
    list multicast-flow {
      key "vpn-rd source-address group-address";
      description
        "Multicast flow information, including keys, upstream and
         downstream nodes, possible signaling protocols, and
         transport protocols.";
		 
      uses general-multicast-key;

      container upstream {
        description
          "Upstream node neighbor information and the signaling
           protocol used in the multicast flow.";

        leaf neighbor-address {
          type inet:ip-address;
          description
            "The IP address of the neighbor.";
        }
        leaf signaling {
          type identityref {
            base dynamic-signaling-type;
          }
          description
            "The type of signaling technology";
        }
      }
      // upstream
      list downstream {
        key "signaling transport";
        description
          "Downstream node neighbor information, the signaling
           protocol and transport protocol used by the multicast
           flow. For different downstream neighbor, different
           signaling and transport technology may be used.";
        
        leaf neighbor-address {
          type inet:ip-address;
          description
            "The IP address of the neighbor.";
        }
        leaf signaling {
          type identityref {
            base dynamic-signaling-type;
          }
          description
            "The type of signaling technology";
        }
        leaf transport {
          type identityref {
            base transport-type;
          }
          description
            "The type of transport technology";
        }
      }
      // downstream
    }
    // multicast-flow
    description
      "Notification events for the upstream or downstream nodes.
       Like node failure, signaling/ transport module
       loading/ unloading. And the potential failure about some
       multicast flows and associated
       signaling/ transport technologies.";
  }
}
<CODE ENDS>
            ]]></artwork>
       <postamble></postamble>
      </figure>
    </section>

   <section title="Security Considerations">
     <t>The "multicast-service" YANG module defines a data model that is designed to be accessed
via YANG-based management protocols, such as NETCONF <xref target="RFC6241"/> and RESTCONF <xref target="RFC8040"/>.
These YANG-based management protocols (1) have to use a secure transport layer
(e.g., SSH <xref target="RFC4252"/>, TLS <xref target="RFC8446"/>, and QUIC <xref target="RFC9000"/>)
and (2) have to use mutual authentication.</t>

     <t>The Network Configuration Access Control Model (NACM) <xref target="RFC8341"/> provides the means
to restrict access for particular Network Configuration Protocl (NETCONF) or RESTCONF users
to a preconfigured subset of all available NETCONF or RESTCONF protocol operations and content.</t>

     <t>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).
All writable data nodes are likely to be reasonably sensitive or vulnerable in some network environments.
Write operations (e.g., edit-config) and delete operations to these data nodes without proper protection
or authentication can have a negative effect on network operations.
The following subtrees and data nodes have particular sensitivities/vulnerabilities:</t>

    <t>'upstream' and 'downstream'
      <list style="simblos">
      <t>These data nodes in this model specifies the configuration for the multicast service
      at the top level. Modifying the configuration can cause multicast service
      to be deleted or reconstructed.</t>
      </list>
   </t>

    <t>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.
Specifically, the following subtrees and data nodes have particular sensitivities/vulnerabilities:</t>

   <t>'upstream' and 'downstream'
      <list style="simblos">
      <t>Unauthorized access to any data node of the above tree can
   disclose the operational state information of multicast service on this
   device.</t>
      </list>
   </t>

   <t>The YANG module defines a set of identities, types, and groupings.
These nodes are intended to be reused by other YANG modules.
The module by itself does not expose any data nodes that are writable,
data nodes that contain read-only state, or RPCs.
As such, there are no additional security issues related to the YANG module that need to be considered.</t>

   <t>Modules that use the groupings that are defined in this document
should identify the corresponding security considerations.
For example, reusing some of these groupings will expose privacy-related information (e.g., 'transport-tech').</t>
   </section>

   <section title="IANA Considerations">
    <t>RFC Ed.: Please replace all occurrences of 'XXXX' with the
   actual RFC number (and remove this note).</t>

    <t> IANA is requested to register the following URI in the "ns"
   subregistry within the "IETF XML Registry" <xref target="RFC3688"/>:</t>

       <t>URI: urn:ietf:params:xml:ns:yang:ietf-multicast</t>
       <t>Registrant Contact: The IESG</t>
       <t>XML: N/A, the requested URI is an XML namespace.</t>

   <t>IANA is requested to register the following YANG module in the "YANG
   Module Names" subregistry <xref target="RFC6020"/> within the "YANG Parameters"
   registry.</t>

       <t>name: ietf-multicast</t>
       <t>Maintained by IANA?  N</t>
       <t>namespace: urn:ietf:params:xml:ns:yang:ietf-multicast</t>
       <t>prefix: ietf-multicast</t>
       <t>reference: RFC XXXX</t>
   </section>

   <section title="Acknowledgements">
    <t>The authors would like to thank Stig Venaas, Jake Holland, Min Gu, Gyan Mishra,
    Jeffrey Zhang for their valuable comments and suggestions.</t>
   </section>

  </middle>

  <!--  *****BACK MATTER ***** -->

  <back>

  <references title='Normative References'>
  &rfc2119;
  &rfc3688;
  &rfc6020;
  &rfc6513;
  &rfc6514;
  &rfc7950;
  &rfc8341;
  &rfc8342;
  &rfc8641;

  </references>

  <references title='Informative References'>
  &rfc4252;
  &rfc4541;
  &rfc4875;
  &rfc4915;
  &rfc5015;
  &rfc5120;
  &rfc6241;
  &rfc6388;
  &rfc7348;
  &rfc7432;
  &rfc7637;
  &rfc7716;
  &rfc7761;
  &rfc7951;
  &rfc7988;
  &rfc8040;
  &rfc8174;
  &rfc8279;
  &rfc8294;
  &rfc8296;
  &rfc8340;
  &rfc8349;
  &rfc8446;
  &rfc8556;
  &rfc8639;
  &rfc8926;
  &rfc9000;
  &rfc9128;
  &rfc9179;
  &rfc9262;
  &rfc9350;
  &rfc9502;
  &rfc9524;
  &rfc9572;
  &rfc9624;
  &rfc9658;
  &rfc9907;
  &rfc9911;
  &I-D.ietf-bier-mld;
  &I-D.ietf-bier-bierin6;
  &I-D.ietf-bier-pim-signaling;
  &I-D.ietf-pim-sr-p2mp-policy;
  &I-D.ietf-mboned-redundant-ingress-failover;
  &I-D.ietf-lsr-flex-soft-dataplane;
  &I-D.ietf-pim-flex-algo;
  </references>
  
    <section title="Data Tree Example"> 
    <t>This section contains an example of an instance data tree in JSON
   encoding <xref target="RFC7951"/>, containing configuration data.</t>
   <t>The configuration example:</t>
 
      <figure align="center">
     <artwork align="center"><![CDATA[
    {
      "ietf-multicast:multicast-service":{
        "multicast-flow":[
          {
            "vpn-rd":"0:65532:4294967292",
            "source-address":"*",
            "group-address":"233.252.0.10",
            "upstream":{
              "neighbor":[
                {
                  "neighbor-address":"198.51.100.10",
                  "vni-type":"tunnel-encap-vxlan",
                  "signaling":"mvpn"
                }
              ]
            }
          },
          {
            "vpn-rd":"0:65532:4294967292",
            "source-address":"*",
            "group-address":"233.252.0.11",
            "downstream":[
              {
                "signaling":"mvpn",
                "transport":"bier",
                "neighbor":[
                  {
                    "neighbor-address":"198.51.100.20"
                  },
                  {
                    "neighbor-address":"198.51.100.30"
                  }
                ],              
                "bier":[
                  {
                    "sub-domain":1,
                    "tad":[
                      {
                        "mt-id":0,
                        "fa-number":200,
                        "data-plane":3
                      }
                    ],
                    "bier-encap-type":"bier-encap-ipv6"
                  }
                ]
              }
            ]
          }
        ]
      }
    }
            ]]></artwork>
       <postamble></postamble>
      </figure>
  </section>
  </back>
</rfc>