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A Yang Data Model for IGMP and MLD Snooping
draft-ietf-pim-igmp-mld-snooping-yang-11

The information below is for an old version of the document.
Document Type
This is an older version of an Internet-Draft that was ultimately published as RFC 9166.
Authors Hongji Zhao , Xufeng Liu , Yisong Liu , Mahesh Sivakumar , Anish Peter
Last updated 2020-05-30
Replaces draft-zhao-pim-igmp-mld-snooping-yang
RFC stream Internet Engineering Task Force (IETF)
Formats
Reviews
Additional resources Mailing list discussion
Stream WG state Submitted to IESG for Publication
Document shepherd Stig Venaas
Shepherd write-up Show Last changed 2019-08-20
IESG IESG state Became RFC 9166 (Proposed Standard)
Consensus boilerplate Yes
Telechat date (None)
Responsible AD Alvaro Retana
Send notices to Stig Venaas <stig@venaas.com>, aretana.ietf@gmail.com
draft-ietf-pim-igmp-mld-snooping-yang-11
PIM Working Group                                               H. Zhao
Internet Draft                                                 Ericsson
Intended status: Standards Track                                 X. Liu
Expires: November 29, 2020                               Volta Networks
                                                                 Y. Liu
                                                           China Mobile
                                                           M. Sivakumar
                                                                Juniper
                                                               A. Peter
                                                             Individual

                                                           May 30, 2020

                A Yang Data Model for IGMP and MLD Snooping
               draft-ietf-pim-igmp-mld-snooping-yang-11.txt

Abstract

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

Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
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   Drafts.

   Internet-Drafts are draft documents valid for a maximum of six months
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   time. It is inappropriate to use Internet-Drafts as reference
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   The list of current Internet-Drafts can be accessed at
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   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html

   This Internet-Draft will expire on November 29, 2020.

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Copyright Notice

   Copyright (c) 2020 IETF Trust and the persons identified as the
   document authors. All rights reserved.

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

Table of Contents

   1. Introduction...................................................3
      1.1. Terminology...............................................3
      1.2. Tree Diagrams.............................................3
      1.3. Prefixes in Data Node Names...............................4
   2. Design of Data Model...........................................4
      2.1. Overview..................................................5
      2.2. Optional Capabilities.....................................5
      2.3. Position of Address Family in Hierarchy...................6
   3. Module Structure...............................................6
      3.1. IGMP Snooping Instances...................................7
      3.2. MLD Snooping Instances....................................9
      3.3. Using IGMP and MLD Snooping Instances....................11
      3.4. IGMP and MLD Snooping RPC................................12
   4. IGMP and MLD Snooping YANG Module.............................12
   5. Security Considerations.......................................34
   6. IANA Considerations...........................................35
   7. References....................................................36
      7.1. Normative References.....................................36
      7.2. Informative References...................................38
   Appendix A.  Data Tree Example...................................39
      A.1 Bridge scenario...........................................39
      A.2 L2VPN scenario............................................42
   Authors' Addresses...............................................46

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1. Introduction

This document defines a YANG [RFC6020] data model for the management of
Internet Group Management Protocol (IGMP) and Multicast Listener
Discovery (MLD) Snooping [RFC4541] devices.

The YANG module in this document conforms to the Network Management
Datastore Architecture defined in [RFC8342]. The "Network Management
Datastore Architecture" (NMDA) adds the ability to inspect the current
operational values for configuration, allowing clients to use identical
paths for retrieving the configured values and the operational values.

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 terminologies are used in this document:

  *  mrouter: multicast router, which means nodes attached to a switch
have multicast routing enabled [RFC4286].

  *  mrouter interfaces: snooping switch ports where multicast routers
are attached [RFC4541].

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

  IGMP: Internet Group Management Protocol [RFC3376].

  MLD:  Multicast Listener Discovery [RFC3810].

  AC:   Attachment Circuit [RFC3916].

  PW:   Pseudo Wire [RFC3916].

1.2. Tree Diagrams

Tree diagrams used in this document follow the notation defined in

[RFC8340].

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1.3. Prefixes in Data Node Names

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

+----------+-----------------------+---------------------------------+
| Prefix   | YANG module           | Reference                       |
+==========+=======================+=================================+
| inet     | ietf-inet-types       | [RFC6991]                       |
+----------+-----------------------+---------------------------------+
| yang     | ietf-yang-types       | [RFC6991]                       |
+----------+-----------------------+---------------------------------+
| if       | ietf-interfaces       | [RFC8343]                       |
+----------+-----------------------+---------------------------------+
| rt       | ietf-routing          | [RFC8349]                       |
+----------+-----------------------+---------------------------------+
| rt-types | ietf-routing-types    | [RFC8294]                       |
+----------+-----------------------+---------------------------------+
| ni       | ietf-network-instance | [RFC8529]                       |
+----------+-----------------------+---------------------------------+
| pw       | ietf-pseudowires      | [draft-ietf-bess-l2vpn-yang]    |
+----------+-----------------------+---------------------------------+
| l2vpn    | ietf-l2vpn            | [draft-ietf-bess-l2vpn-yang]    |
+----------+-----------------------+---------------------------------+
| dot1q    | ieee802-dot1q-bridge  | [dot1Qcp]                       |
+----------+-----------------------+---------------------------------+
      Table 1: Prefixes and Corresponding YANG Modules

2. Design of Data Model

An IGMP/MLD snooping switch [RFC4541] analyzes IGMP/MLD packets and sets
up forwarding tables for multicast traffic. If a switch does not run
IGMP/MLD snooping, multicast traffic will be flooded in the broadcast
domain. If a switch runs IGMP/MLD snooping, multicast traffic will be
forwarded based on the forwarding tables to avoid bandwidth waste. The
IGMP/MLD snooping switch does not need to run any of the IGMP/MLD
protocols. Because the IGMP/MLD snooping is independent of the IGMP/MLD

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protocols, the data model defined in this document does not augment, or
even require, the IGMP/MLD data model defined in [RFC8652].
The model covers considerations for Internet Group Management Protocol
(IGMP) and Multicast Listener Discovery (MLD) Snooping Switches
[RFC4541].

IGMP and MLD snooping switches do not adhere to the conceptual model
that provides the strict separation of functionality between different
communications layers in the ISO model, and instead utilize information
in the upper level protocol headers as factors to be considered in
processing at the lower levels [RFC4541].

IGMP Snooping switches utilize IGMP, and could support IGMPv1 [RFC1112],
IGMPv2 [RFC2236], and IGMPv3 [RFC3376]. MLD Snooping switches utilize
MLD, and could support MLDv1 [RFC2710] and MLDv2 [RFC3810]. The goal of
this document is to define a data model that provides a common user
interface to IGMP and MLD Snooping.

2.1. Overview

The IGMP and MLD Snooping YANG module defined in this document has all
the common building blocks for the IGMP and MLD Snooping switches.

The YANG module includes IGMP and MLD Snooping instance definition,
using instance in the scenario of BRIDGE [dot1Qcp] and L2VPN [draft-
ietf-bess-l2vpn-yang]. The module also includes the RPC methods for
clearing IGMP and MLD Snooping group tables.

This YANG module conforms to Network Management Datastore Architecture
(NMDA)[RFC8342]. This NMDA architecture provides an architectural
framework for datastores as they are used by network management
protocols such as NETCONF [RFC6241], RESTCONF [RFC8040] and the YANG
[RFC7950] data modeling language.

2.2. Optional Capabilities

This model is designed to represent the basic capability subsets of IGMP
and MLD Snooping. The main design goals of this document are that the
basic capabilities described in the model are supported by any major
now-existing implementation, and that the configuration of all
implementations meeting the specifications is easy to express through
some combination of the optional features in the model and simple vendor
augmentations.

There is also value in widely supported features being standardized, to
provide a standardized way to access these features, to save work for
individual vendors, and so that mapping between different vendors'
configuration is not needlessly complicated. Therefore, this model
declares a number of features representing capabilities that not all
deployed devices support.

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The extensive use of feature declarations should also substantially
simplify the capability negotiation process for a vendor's IGMP and MLD
Snooping implementations.

On the other hand, operational state parameters are not so widely
designated as features, as there are many cases where the defaulting
of an operational state parameter would not cause any harm to the
system, and it is much more likely that an implementation without
native support for a piece of operational state would be able to derive
a suitable value for a state variable that is not natively supported.

2.3. Position of Address Family in Hierarchy

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

This document defines IGMP Snooping and MLD Snooping as separate schema
branches in the structure. The benefits are:

*  The model can support IGMP Snooping (IPv4), MLD Snooping (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
[RFC8652], which uses separate branches for IPv4 and IPv6.

*  The separate branches for IGMP Snooping and MLD Snooping can
accommodate their differences better and cleaner. 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-snooping-instance <= Augmented by this Model
                        ...
         |     +--rw mld-snooping-instance   <= Augmented by this Model
                        ...
The "igmp-snooping-instance" container instantiates an IGMP Snooping
Instance. The "mld-snooping-instance" container instantiates an MLD
Snooping Instance.

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The YANG data model defined in this document conforms to the Network
Management Datastore Architecture (NMDA) [RFC8342].  The operational
state data is combined with the associated configuration data in the
same hierarchy [RFC8407].

A configuration data node is marked as mandatory only when its value
must be provided by the user.  Where nodes are not essential to protocol
operation, they are marked as optional.  Some other nodes are essential
but have a default specified, so that they are also optional and need
not be configured explicitly.

3.1. IGMP Snooping Instances

The YANG module defines igmp-snooping-instance which augments
/rt:routing/rt:control-plane-protocols/rt:control-plane-protocol.

All the IGMP Snooping related attributes have been defined in the igmp-
snooping-instance. The read-write attribute represents configurable
data. The read-only attribute represents state data.

One igmp-snooping-instance could be used in one BRIDGE [dot1Qcp]
instance or L2VPN [draft-ietf-bess-l2vpn-yang] instance. One igmp-
snooping-instance corresponds to one BRIDGE instance or one L2VPN
instance.

The value of scenario in igmp-snooping-instance is bridge or l2vpn. When
it is bridge, igmp-snooping-instance will be used in the BRIDGE
scenario. When it is l2vpn, igmp-snooping-instance will be used in the
L2VPN scenario.

The value of bridge-mrouter-interface, l2vpn-mrouter-interface-ac,
l2vpn-mrouter-interface-pw are filled by the snooping device
dynamically. They are different from static-bridge-mrouter-interface,
static-l2vpn-mrouter-interface-ac, and static-l2vpn-mrouter-interface-pw
which are configured statically.

The attributes under the interfaces show the statistics of IGMP Snooping
related packets.

  augment /rt:routing/rt:control-plane-protocols
            /rt:control-plane-protocol:
    +--rw igmp-snooping-instance {feature-igmp-snooping}?
    |  +--rw scenario?
    |  |       snooping-scenario-type
    |  +--rw enable?                              boolean
    |  +--rw forwarding-table-type?               enumeration
    |  +--rw explicit-tracking?                   boolean
    |  |       {feature-explicit-tracking}?
    |  +--rw exclude-lite?                        boolean
    |  |       {feature-exclude-lite}?
    |  +--rw send-query?                          boolean
    |  +--rw immediate-leave?                     empty
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    |  |       {feature-immediate-leave}?
    |  +--rw last-member-query-interval?          uint16
    |  +--rw query-interval?                      uint16
    |  +--rw query-max-response-time?             uint16
    |  +--rw require-router-alert?                boolean
    |  |       {feature-require-router-alert}?
    |  +--rw robustness-variable?                 uint8
    |  +--rw static-bridge-mrouter-interface*     if:interface-ref
    |  |       {static-mrouter-interface}?
    |  +--rw static-l2vpn-mrouter-interface-ac*   if:interface-ref
    |  |       {static-mrouter-interface}?
    |  +--rw static-l2vpn-mrouter-interface-pw*   pw:pseudowire-ref
    |  |       {static-mrouter-interface}?
    |  +--rw igmp-version?                        uint8
    |  +--rw querier-source?                      inet:ipv4-address
    |  +--rw static-l2-multicast-group* [group source-addr]
    |  |       {feature-static-l2-multicast-group}?
    |  |  +--rw group
    |  |  |       rt-types:ipv4-multicast-group-address
    |  |  +--rw source-addr
    |  |  |       rt-types:ipv4-multicast-source-address
    |  |  +--rw bridge-outgoing-interface*   if:interface-ref
    |  |  +--rw l2vpn-outgoing-ac*           if:interface-ref
    |  |  +--rw l2vpn-outgoing-pw*           pw:pseudowire-ref
    |  +--ro entries-count?                       uint32
    |  +--ro bridge-mrouter-interface*            if:interface-ref
    |  +--ro l2vpn-mrouter-interface-ac*          if:interface-ref
    |  +--ro l2vpn-mrouter-interface-pw*          pw:pseudowire-ref
    |  +--ro group* [address]
    |  |  +--ro address
    |  |  |       rt-types:ipv4-multicast-group-address
    |  |  +--ro mac-address?     yang:phys-address
    |  |  +--ro expire?          rt-types:timer-value-seconds16
    |  |  +--ro up-time          uint32
    |  |  +--ro last-reporter?   inet:ipv4-address
    |  |  +--ro source* [address]
    |  |     +--ro address
    |  |     |       rt-types:ipv4-multicast-source-address
    |  |     +--ro bridge-outgoing-interface*   if:interface-ref
    |  |     +--ro l2vpn-outgoing-ac*           if:interface-ref
    |  |     +--ro l2vpn-outgoing-pw*           pw:pseudowire-ref
    |  |     +--ro up-time                      uint32
    |  |     +--ro expire?
    |  |     |       rt-types:timer-value-seconds16
    |  |     +--ro host-count?                  uint32
    |  |     |       {feature-explicit-tracking}?
    |  |     +--ro last-reporter?               inet:ipv4-address
    |  |     +--ro host* [host-address] {feature-explicit-tracking}?
    |  |        +--ro host-address        inet:ipv4-address
    |  |        +--ro host-filter-mode    filter-mode-type
    |  +--ro interfaces
    |     +--ro interface* [name]
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    |        +--ro name          if:interface-ref
    |        +--ro statistics
    |           +--ro received
    |           |  +--ro num-query?                  yang:counter64
    |           |  +--ro num-membership-report-v1?   yang:counter64
    |           |  +--ro num-membership-report-v2?   yang:counter64
    |           |  +--ro num-membership-report-v3?   yang:counter64
    |           |  +--ro num-leave?                  yang:counter64
    |           |  +--ro num-non-member-leave?       yang:counter64
    |           |  +--ro num-pim-hello?              yang:counter64
    |           +--ro sent
    |              +--ro num-query?                  yang:counter64
    |              +--ro num-membership-report-v1?   yang:counter64
    |              +--ro num-membership-report-v2?   yang:counter64
    |              +--ro num-membership-report-v3?   yang:counter64
    |              +--ro num-leave?                  yang:counter64
    |              +--ro num-non-member-leave?       yang:counter64
    |              +--ro num-pim-hello?              yang:counter64

3.2. MLD Snooping Instances

The YANG module defines mld-snooping-instance which could be used in the
BRIDGE [dot1Qcp] or L2VPN [draft-ietf-bess-l2vpn-yang] scenario to
enable MLD Snooping.

All the MLD Snooping related attributes have been defined in the mld-
snooping-instance. The read-write attribute represents configurable
data. The read-only attribute represents state data.

The mld-snooping-instance is the same as IGMP snooping except changing
IPv4 addresses to IPv6 addresses. One mld-snooping-instance could be
used in one BRIDGE instance or L2VPN instance. One mld-snooping-instance
corresponds to one BRIDGE instance or L2VPN instance.

The value of scenario in mld-snooping-instance is bridge or l2vpn. When
it is bridge, mld-snooping-instance will be used in the BRIDGE scenario.
When it is l2vpn, mld-snooping-instance will be used in the L2VPN
scenario.

The value of bridge-mrouter-interface, l2vpn-mrouter-interface-ac,
l2vpn-mrouter-interface-pw are filled by the snooping device
dynamically. They are different from static-bridge-mrouter-interface,
static-l2vpn-mrouter-interface-ac, and static-l2vpn-mrouter-interface-pw
which are configured statically.

The attributes under the interfaces show the statistics of MLD Snooping
related packets.

  augment /rt:routing/rt:control-plane-protocols
            /rt:control-plane-protocol:
   +--rw igmp-snooping-instance {feature-igmp-snooping}?
   ..
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   +--rw mld-snooping-instance {feature-mld-snooping}?
          +--rw scenario?
          |       snooping-scenario-type
          +--rw enable?                              boolean
          +--rw forwarding-table-type?               enumeration
          +--rw explicit-tracking?                   boolean
          |       {feature-explicit-tracking}?
          +--rw exclude-lite?                        boolean
          |       {feature-exclude-lite}?
          +--rw send-query?                          boolean
          +--rw immediate-leave?                     empty
          |       {feature-immediate-leave}?
          +--rw last-member-query-interval?          uint16
          +--rw query-interval?                      uint16
          +--rw query-max-response-time?             uint16
          +--rw require-router-alert?                boolean
          |       {feature-require-router-alert}?
          +--rw robustness-variable?                 uint8
          +--rw static-bridge-mrouter-interface*     if:interface-ref
          |       {static-mrouter-interface}?
          +--rw static-l2vpn-mrouter-interface-ac*   if:interface-ref
          |       {static-mrouter-interface}?
          +--rw static-l2vpn-mrouter-interface-pw*   pw:pseudowire-ref
          |       {static-mrouter-interface}?
          +--rw mld-version?                         uint8
          +--rw querier-source?                      inet:ipv6-address
          +--rw static-l2-multicast-group* [group source-addr]
          |       {feature-static-l2-multicast-group}?
          |  +--rw group
          |  |       rt-types:ipv6-multicast-group-address
          |  +--rw source-addr
          |  |       rt-types:ipv6-multicast-source-address
          |  +--rw bridge-outgoing-interface*   if:interface-ref
          |  +--rw l2vpn-outgoing-ac*           if:interface-ref
          |  +--rw l2vpn-outgoing-pw*           pw:pseudowire-ref
          +--ro entries-count?                       uint32
          +--ro bridge-mrouter-interface*            if:interface-ref
          +--ro l2vpn-mrouter-interface-ac*          if:interface-ref
          +--ro l2vpn-mrouter-interface-pw*          pw:pseudowire-ref
          +--ro group* [address]
          |  +--ro address
          |  |       rt-types:ipv6-multicast-group-address
          |  +--ro mac-address?     yang:phys-address
          |  +--ro expire?          rt-types:timer-value-seconds16
          |  +--ro up-time          uint32
          |  +--ro last-reporter?   inet:ipv6-address
          |  +--ro source* [address]
          |     +--ro address
          |     |       rt-types:ipv6-multicast-source-address
          |     +--ro bridge-outgoing-interface*   if:interface-ref
          |     +--ro l2vpn-outgoing-ac*           if:interface-ref
          |     +--ro l2vpn-outgoing-pw*           pw:pseudowire-ref
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          |     +--ro up-time                      uint32
          |     +--ro expire?
          |     |       rt-types:timer-value-seconds16
          |     +--ro host-count?                  uint32
          |     |       {feature-explicit-tracking}?
          |     +--ro last-reporter?               inet:ipv6-address
          |     +--ro host* [host-address] {feature-explicit-tracking}?
          |        +--ro host-address        inet:ipv6-address
          |        +--ro host-filter-mode    filter-mode-type
          +--ro interfaces
             +--ro interface* [name]
                +--ro name          if:interface-ref
                +--ro statistics
                   +--ro received
                   |  +--ro num-query?       yang:counter64
                   |  +--ro num-report-v1?   yang:counter64
                   |  +--ro num-report-v2?   yang:counter64
                   |  +--ro num-done?        yang:counter64
                   |  +--ro num-pim-hello?   yang:counter64
                   +--ro sent
                      +--ro num-query?       yang:counter64
                      +--ro num-report-v1?   yang:counter64
                      +--ro num-report-v2?   yang:counter64
                      +--ro num-done?        yang:counter64
                      +--ro num-pim-hello?   yang:counter64

3.3. Using IGMP and MLD Snooping Instances

The igmp-snooping-instance could be used in the scenario of BRIDGE
[dot1Qcp] or L2VPN [draft-ietf-bess-l2vpn-yang] to configure the IGMP
Snooping.

For the BRIDGE scenario this model augments /dot1q:bridges/dot1q:bridge
to use igmp-snooping-instance. It means IGMP Snooping is enabled in the
whole bridge.

It also augments /dot1q:bridges/dot1q:bridge/dot1q:component/
dot1q:bridge-vlan/dot1q:vlan to use igmp-snooping-instance. It means
IGMP Snooping is enabled in the specified VLAN on the bridge.

     augment /dot1q:bridges/dot1q:bridge:
       +--rw igmp-snooping-instance?   igmp-mld-snooping-instance-ref
       +--rw mld-snooping-instance?    igmp-mld-snooping-instance-ref

     augment /dot1q:bridges/dot1q:bridge/dot1q:component
               /dot1q:bridge-vlan/dot1q:vlan:
       +--rw igmp-snooping-instance?   igmp-mld-snooping-instance-ref
       +--rw mld-snooping-instance?    igmp-mld-snooping-instance-ref

For the L2VPN scenario this model augments /ni:network-instances/
ni:network-instance/ni:ni-type/l2vpn:l2vpn [RFC8529] to use igmp-
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snooping-instance. It means IGMP Snooping is enabled in the specified
l2vpn instance.

     augment /ni:network-instances/ni:network-instance/ni:ni-type
               /l2vpn:l2vpn:
       +--rw igmp-snooping-instance?   igmp-mld-snooping-instance-ref
       +--rw mld-snooping-instance?    igmp-mld-snooping-instance-ref

The mld-snooping-instance could be used in concurrence with igmp-
snooping-instance to configure the MLD Snooping.

3.4. IGMP and MLD Snooping RPC

IGMP and MLD Snooping RPC clears the specified IGMP and MLD Snooping
group tables.

  rpcs:
    +---x clear-igmp-snooping-groups {rpc-clear-groups}?
    |  +---w input
    |     +---w name?     igmp-mld-snooping-instance-ref
    |     |       {feature-igmp-snooping}?
    |     +---w group?    rt-types:ipv4-multicast-group-address
    |     +---w source?   rt-types:ipv4-multicast-source-address
    +---x clear-mld-snooping-groups {rpc-clear-groups}?
       +---w input
          +---w name?     igmp-mld-snooping-instance-ref
          |       {feature-mld-snooping}?
          +---w group?    rt-types:ipv6-multicast-group-address
          +---w source?   rt-types:ipv6-multicast-source-address

4. IGMP and MLD Snooping YANG Module

This module references [RFC3376],[RFC4541],[RFC6636],[RFC6991],
[RFC8343],[RFC8529],[dot1Qcp], and [draft-ietf-bess-l2vpn-yang].

<CODE BEGINS> file ietf-igmp-mld-snooping@2020-04-29.yang
module ietf-igmp-mld-snooping {
  yang-version 1.1;
  namespace "urn:ietf:params:xml:ns:yang:ietf-igmp-mld-snooping";

  prefix ims;

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

  import ietf-yang-types {
    prefix "yang";
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    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-l2vpn {
    prefix "l2vpn";
    reference
      "draft-ietf-bess-l2vpn-yang: YANG Data Model for MPLS-based
L2VPN";
  }

  import ietf-network-instance {
    prefix "ni";
    reference
      "RFC 8529: YANG Data Model for Network Instances";
  }

  import ietf-pseudowires {
    prefix "pw";
    reference
      "draft-ietf-bess-l2vpn-yang: YANG Data Model for MPLS-based
L2VPN";
  }

  import ieee802-dot1q-bridge {
    prefix "dot1q";
    reference
      "dot1Qcp: IEEE 802.1Qcp-2018 Bridges and Bridged Networks
                - Amendment: YANG Data Model";
  }

  organization
    "IETF PIM Working Group";
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  contact
    "WG Web:   <http://tools.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>

               Anish Peter
               <mailto:anish.ietf@gmail.com>

               Mahesh Sivakumar
               <mailto:sivakumar.mahesh@gmail.com>

    ";

  description
    "The module defines a collection of YANG definitions common for
     all devices that implement Internet Group Management Protocol
     (IGMP) and Multicast Listener Discovery (MLD) Snooping [RFC 4541].

     Copyright (c) 2020 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

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

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

  revision 2020-04-29 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for IGMP and MLD Snooping";
  }

  /*
   * Features
   */

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  feature feature-igmp-snooping {
    description
      "Support IGMP snooping.";
  }

  feature feature-mld-snooping {
    description
      "Support MLD snooping.";
  }

  feature feature-immediate-leave {
    description
      "Support configuration of immediate-leave.";
  }

  feature feature-static-l2-multicast-group {
    description
      "Support configuration of L2 multicast static-group.";
  }

  feature static-mrouter-interface {
    description
      "Support configuration of mrouter interface.";
  }

  feature rpc-clear-groups {
    description
      "Support clearing statistics by RPC for IGMP & MLD snooping.";
  }

  feature feature-require-router-alert {
    description
      "Support configuration of require-router-alert.";
    reference
      "RFC 3376, Section 5.2";
  }

  feature feature-exclude-lite {
    description
      "Support configuration of per instance exclude-lite.";
    reference
      "RFC 5790, Section 3";
  }

  feature feature-explicit-tracking {
    description
      "Support configuration of per instance explicit-tracking.";
    reference
      "RFC 6636, Section 3";
  }

  /* identities */
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  identity scenario-type {
    description
      "Base identity for scenario type in IGMP & MLD snooping";
  }

  identity bridge {
    base scenario-type;
    description
      "This identity represents BRIDGE scenario.";
  }

  identity l2vpn {
    base scenario-type;
    description
      "This identity represents L2VPN scenario.";
  }

  identity filter-mode {
    description
      "Base identity for filter mode in IGMP & MLD snooping";
  }

  identity include {
    base filter-mode;
    description
      "This identity represents include mode.";
  }

  identity exclude {
    base filter-mode;
    description
      "This identity represents exclude mode.";
  }

  identity igmp-snooping {
    base rt:control-plane-protocol;
    description
      "IGMP snooping";
  }

  identity mld-snooping {
    base rt:control-plane-protocol;
    description
      "MLD snooping";
  }

  /*
   * Typedefs
   */

  typedef snooping-scenario-type {
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    type identityref {
      base "scenario-type";
    }
    description "The IGMP & MLD snooping scenario type";
  }

  typedef filter-mode-type {
    type identityref {
      base "filter-mode";
    }
    description "The host filter mode";
  }

  typedef igmp-mld-snooping-instance-ref {
    type leafref {
      path "/rt:routing/rt:control-plane-protocols"+
        "/rt:control-plane-protocol/rt:name";
    }
    description
      "This type is used by data models which need to
       reference IGMP & MLD snooping instance.";
  }

  /*
   * Groupings
   */

  grouping instance-config-attributes-igmp-snooping {
    description
      "IGMP snooping configuration for each BRIDGE or L2VPN instance.";

    uses instance-config-attributes-igmp-mld-snooping;

    leaf igmp-version {
      type uint8 {
        range "1..3";
      }
      default 2;
      description "IGMP version.";
    }

    leaf querier-source {
      type inet:ipv4-address;
      description
        "Use the IGMP snooping querier to support IGMP
         snooping in a VLAN where PIM and IGMP are not configured.
         The IPv4 address is used as source address in messages.";
    }

    list static-l2-multicast-group {
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      if-feature feature-static-l2-multicast-group;
      key "group source-addr";
      description
        "A static multicast route, (*,G) or (S,G).";

      leaf group {
        type rt-types:ipv4-multicast-group-address;
        description
          "Multicast group IPv4 address";
      }

      leaf source-addr {
        type rt-types:ipv4-multicast-source-address;
        description
          "Multicast source IPv4 address.";
      }

      leaf-list bridge-outgoing-interface {
        when 'derived-from-or-self(../../scenario,"ims:bridge")';
        type if:interface-ref;
        description "Outgoing interface in BRIDGE forwarding";
      }

      leaf-list l2vpn-outgoing-ac {
        when 'derived-from-or-self(../../scenario,"ims:l2vpn")';
        type if:interface-ref;
        description "Outgoing Attachment Circuit (AC) in L2VPN
forwarding";
      }

      leaf-list l2vpn-outgoing-pw {
        when 'derived-from-or-self(../../scenario,"ims:l2vpn")';
        type pw:pseudowire-ref;
        description "Outgoing Pseudo Wire (PW) in L2VPN forwarding";
      }
    } // static-l2-multicast-group
  } // instance-config-attributes-igmp-snooping

  grouping instance-config-attributes-igmp-mld-snooping {
    description
      "IGMP and MLD snooping configuration of each VLAN.";

    leaf enable {
      type boolean;
      default false;
        description
          "Set the value to true to enable IGMP & MLD snooping.";
    }

    leaf forwarding-table-type {
      type enumeration {
        enum "mac" {
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          description
          "MAC-based lookup mode";
        }
        enum "ip"  {
          description
          "IP-based lookup mode";
        }
      }
      default "ip";
      description "The default forwarding table type is ip";
    }

    leaf explicit-tracking {
      if-feature feature-explicit-tracking;
      type boolean;
      default false;
      description
        "Track the IGMPv3 and MLDv2 snooping membership reports
         from individual hosts. It contributes to saving network
         resources and shortening leave latency.";
    }

    leaf exclude-lite {
      if-feature feature-exclude-lite;
      type boolean;
      default false;
      description
        "Track the Lightweight IGMPv3 and MLDv2 protocol report";
      reference "RFC 5790";
    }

    leaf send-query {
      type boolean;
      default false;
      description
        "Enable quick response for topology changes.
         To support IGMP snooping in a VLAN where PIM and IGMP are
         not configured. It cooperates with parameter querier-source.";
    }

    leaf immediate-leave {
      if-feature feature-immediate-leave;
      type empty;
      description
        "When immediate leave is enabled, the IGMP software assumes
         that no more than one host is present on each VLAN port.";
    }

    leaf last-member-query-interval {
      type uint16 {
        range "10..10230";
      }
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      units one-tenth-second;
      default 10;
      description
        "Last Member Query Interval, which may be tuned to modify
         the leave latency of the network.
         It is represented in units of 1/10 second.";
      reference "RFC 3376. Sec. 8.8.";
    }

    leaf query-interval {
      type uint16;
      units seconds;
      default 125;
      description
        "The Query Interval is the interval between General Queries
         sent by the Querier.";
      reference "RFC 3376. Sec. 4.1.7, 8.2, 8.14.2.";
    }

    leaf query-max-response-time {
      type uint16;
      units one-tenth-second;
      default 100;
      description
        "Query maximum response time specifies the maximum time
         allowed before sending a responding report.
         It is represented in units of 1/10 second.";
      reference "RFC 3376. Sec. 4.1.1, 8.3, 8.14.3.";
    }

    leaf require-router-alert {
      if-feature feature-require-router-alert;
      type boolean;
      default false;
      description
        "When the value is true, router alert should exist
         in the IP header of IGMP or MLD packet.";
    }

    leaf robustness-variable {
      type uint8 {
        range "1..7";
      }
      default 2;
      description
        "Querier's Robustness Variable allows tuning for the
         expected packet loss on a network.";
      reference "RFC 3376. Sec. 4.1.6, 8.1, 8.14.1.";
    }

    leaf-list static-bridge-mrouter-interface {
      when 'derived-from-or-self(../scenario,"ims:bridge")';
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      if-feature static-mrouter-interface;
      type if:interface-ref;
      description "static mrouter interface in BRIDGE forwarding";
    }

    leaf-list static-l2vpn-mrouter-interface-ac {
      when 'derived-from-or-self(../scenario,"ims:l2vpn")';
      if-feature static-mrouter-interface;
      type if:interface-ref;
      description
        "static mrouter interface whose type is interface
         in L2VPN forwarding";
    }

    leaf-list static-l2vpn-mrouter-interface-pw {
      when 'derived-from-or-self(../scenario,"ims:l2vpn")';
      if-feature static-mrouter-interface;
      type pw:pseudowire-ref;
      description
        "static mrouter interface whose type is PW
         in L2VPN forwarding";
    }
  } // instance-config-attributes-igmp-mld-snooping

  grouping instance-config-attributes-mld-snooping {
    description "MLD snooping configuration of each VLAN.";

    uses instance-config-attributes-igmp-mld-snooping;

    leaf mld-version {
      type uint8 {
        range "1..2";
      }
      default 2;
      description "MLD version.";
    }

    leaf querier-source {
      type inet:ipv6-address;
      description
        "Use the MLD snooping querier to support MLD snooping where
         PIM and MLD are not configured. The IPv6 address is used as
         the source address in messages.";
    }

    list static-l2-multicast-group {
      if-feature feature-static-l2-multicast-group;
      key "group source-addr";
      description
        "A static multicast route, (*,G) or (S,G).";

      leaf group {
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        type rt-types:ipv6-multicast-group-address;
        description
          "Multicast group IPv6 address";
      }

      leaf source-addr {
        type rt-types:ipv6-multicast-source-address;
        description
          "Multicast source IPv6 address.";
      }

      leaf-list bridge-outgoing-interface {
       when 'derived-from-or-self(../../scenario,"ims:bridge")';
       type if:interface-ref;
       description "Outgoing interface in BRIDGE forwarding";
      }

      leaf-list l2vpn-outgoing-ac {
       when 'derived-from-or-self(../../scenario,"ims:l2vpn")';
       type if:interface-ref;
       description "Outgoing Attachment Circuit (AC) in L2VPN
forwarding";
      }

      leaf-list l2vpn-outgoing-pw {
       when 'derived-from-or-self(../../scenario,"ims:l2vpn")';
       type pw:pseudowire-ref;
       description "Outgoing Pseudo Wire (PW) in L2VPN forwarding";
      }
    } // static-l2-multicast-group
  } // instance-config-attributes-mld-snooping

  grouping instance-state-group-attributes-igmp-mld-snooping {
    description
      "Attributes for both IGMP and MLD snooping groups.";

    leaf mac-address {
      type yang:phys-address;
      description "Destination MAC address for L2 multicast.";
    }

    leaf expire {
      type rt-types:timer-value-seconds16;
      units seconds;
      description
        "The time left before multicast group timeout.";
    }

    leaf up-time {
      type uint32;
      units seconds;
      mandatory true;
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      description
        "The time elapsed since L2 multicast record created.";
    }
  } // instance-state-group-attributes-igmp-mld-snooping

  grouping instance-state-attributes-igmp-snooping {
    description
      "State attributes for IGMP snooping for each instance.";

    uses instance-state-attributes-igmp-mld-snooping;

    list group {

      key "address";

      config false;

      description "IGMP snooping information";

      leaf address {
        type rt-types:ipv4-multicast-group-address;
        description
          "Multicast group IPv4 address";
      }

      uses instance-state-group-attributes-igmp-mld-snooping;

      leaf last-reporter {
        type inet:ipv4-address;
        description
          "Address of the last host which has sent report to join
           the multicast group.";
      }

      list source {
        key "address";
        description "Source IPv4 address for multicast stream";

        leaf address {
          type rt-types:ipv4-multicast-source-address;
          description "Source IPv4 address for multicast stream";
        }

        uses instance-state-source-attributes-igmp-mld-snooping;

        leaf last-reporter {
          type inet:ipv4-address;
          description
            "Address of the last host which has sent report
             to join the multicast group.";
        }
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        list host {
          if-feature feature-explicit-tracking;
          key "host-address";
          description
            "List of multicast membership hosts
             of the specific multicast source-group.";

          leaf host-address {
            type inet:ipv4-address;
            description
              "Multicast membership host address.";
          }
          leaf host-filter-mode {
            type filter-mode-type;
            mandatory true;
            description
              "Filter mode for a multicast membership
               host may be either include or exclude.";
          }
        }// list host

      } // list source
    } // list group
  } // instance-state-attributes-igmp-snooping

  grouping instance-state-attributes-igmp-mld-snooping {

    description
      "State attributes for IGMP & MLD snooping instance.";

    leaf entries-count {
      type uint32;
      config false;
      description
       "The number of L2 multicast entries in IGMP & MLD snooping";
    }

    leaf-list bridge-mrouter-interface {
      when 'derived-from-or-self(../scenario,"ims:bridge")';
      type if:interface-ref;
      config false;
      description "mrouter interface in BRIDGE forwarding";
    }

    leaf-list l2vpn-mrouter-interface-ac {
      when 'derived-from-or-self(../scenario,"ims:l2vpn")';
      type if:interface-ref;
      config false;
      description
        "mrouter interface whose type is interface
         in L2VPN forwarding";
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    }

    leaf-list l2vpn-mrouter-interface-pw {
      when 'derived-from-or-self(../scenario,"ims:l2vpn")';
      type pw:pseudowire-ref;
      config false;
      description
        "mrouter interface whose type is PW in L2VPN forwarding";
    }
  } // instance-config-attributes-igmp-mld-snooping

  grouping instance-state-attributes-mld-snooping {
    description
      "State attributes for MLD snooping of each VLAN.";

    uses instance-state-attributes-igmp-mld-snooping;

    list group {
      key "address";
      config false;
      description "MLD snooping statistics information";

      leaf address {
        type rt-types:ipv6-multicast-group-address;
        description
          "Multicast group IPv6 address";
      }

      uses instance-state-group-attributes-igmp-mld-snooping;

      leaf last-reporter {
        type inet:ipv6-address;
        description
          "Address of the last host which has sent report
           to join the multicast group.";
      }

      list source {
        key "address";
        description "Source IPv6 address for multicast stream";

        leaf address {
          type rt-types:ipv6-multicast-source-address;
          description "Source IPv6 address for multicast stream";
        }

        uses instance-state-source-attributes-igmp-mld-snooping;

        leaf last-reporter {
         type inet:ipv6-address;
         description
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          "Address of the last host which has sent report
           to join the multicast group.";
        }

        list host {
          if-feature feature-explicit-tracking;
          key "host-address";
          description
            "List of multicast membership hosts
             of the specific multicast source-group.";

          leaf host-address {
            type inet:ipv6-address;
            description
              "Multicast membership host address.";
          }
          leaf host-filter-mode {
            type filter-mode-type;
            mandatory true;
            description
              "Filter mode for a multicast membership
               host may be either include or exclude.";
          }
        }// list host
      } // list source
    } // list group
  } // instance-state-attributes-mld-snooping

  grouping instance-state-source-attributes-igmp-mld-snooping {
    description
      "State attributes for IGMP & MLD snooping instance.";

    leaf-list bridge-outgoing-interface {
      when 'derived-from-or-self(../../../scenario,"ims:bridge")';
      type if:interface-ref;
      description "Outgoing interface in BRIDGE forwarding";
    }

    leaf-list l2vpn-outgoing-ac {
      when 'derived-from-or-self(../../../scenario,"ims:l2vpn")';
      type if:interface-ref;
      description "Outgoing Attachment Circuit (AC) in L2VPN
forwarding";
    }

    leaf-list l2vpn-outgoing-pw {
      when 'derived-from-or-self(../../../scenario,"ims:l2vpn")';
      type pw:pseudowire-ref;
      description "Outgoing Pseudo Wire (PW) in L2VPN forwarding";
    }

    leaf up-time {
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      type uint32;
      units seconds;
      mandatory true;
      description
        "The time elapsed since L2 multicast record created";
    }

    leaf expire {
      type rt-types:timer-value-seconds16;
      units seconds;
      description
        "The time left before multicast group timeout.";
    }

    leaf host-count {
      if-feature feature-explicit-tracking;
      type uint32;
      description
        "The number of host addresses.";
    }
  } // instance-state-source-attributes-igmp-mld-snooping

  grouping igmp-snooping-statistics {
    description
      "The statistics attributes for IGMP snooping.";

      leaf num-query {
        type yang:counter64;
        description
          "The number of query messages.";
      }
      leaf num-membership-report-v1 {
        type yang:counter64;
        description
          "The number of membership report v1 messages.";
      }
      leaf num-membership-report-v2 {
        type yang:counter64;
        description
          "The number of membership report v2 messages.";
      }
      leaf num-membership-report-v3 {
        type yang:counter64;
        description
          "The number of membership report v3 messages.";
      }
      leaf num-leave {
        type yang:counter64;
        description
          "The number of leave messages.";
      }
      leaf num-non-member-leave {
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        type yang:counter64;
        description
          "The number of non member leave messages.";
      }
      leaf num-pim-hello {
        type yang:counter64;
        description
          "The number of PIM hello messages.";
      }
  } // igmp-snooping-statistics

  grouping mld-snooping-statistics {
    description
      "The statistics attributes for MLD snooping.";

      leaf num-query {
        type yang:counter64;
        description
          "The number of Multicast Listener Query messages.";
      }
      leaf num-report-v1 {
        type yang:counter64;
        description
          "The number of Version 1 Multicast Listener Report.";
      }
      leaf num-report-v2 {
        type yang:counter64;
        description
          "The number of Version 2 Multicast Listener Report.";
      }
      leaf num-done {
        type yang:counter64;
        description
          "The number of Version 1 Multicast Listener Done.";
      }
      leaf num-pim-hello {
        type yang:counter64;
        description
          "The number of PIM hello messages.";
      }
  } // mld-snooping-statistics

  grouping igmp-snooping-interface-statistics-attributes {

    description "Interface statistics attributes for IGMP snooping";

    container interfaces {
       config false;

       description
         "Interfaces associated with the IGMP snooping instance";

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       list interface {
         key "name";

         description
           "Interfaces associated with the IGMP snooping instance";

         leaf name {
           type if:interface-ref;
           description
             "The name of interface";

         }

         container statistics {
           description
             "The interface statistics for IGMP snooping";

           container received {
             description
               "Statistics of received IGMP snooping packets.";

             uses igmp-snooping-statistics;
           }
           container sent {
             description
               "Statistics of sent IGMP snooping packets.";

             uses igmp-snooping-statistics;
           }
         }
       }
    }
  }//igmp-snooping-interface-statistics-attributes

  grouping mld-snooping-interface-statistics-attributes {

    description "Interface statistics attributes for MLD snooping";

    container interfaces {
       config false;

       description
         "Interfaces associated with the MLD snooping instance";

       list interface {
         key "name";

         description
           "Interfaces associated with the MLD snooping instance";

         leaf name {
           type if:interface-ref;
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           description
             "The name of interface";

         }

         container statistics {
           description
             "The interface statistics for MLD snooping";

           container received {
             description
               "Statistics of received MLD snooping packets.";

             uses mld-snooping-statistics;
           }
           container sent {
             description
               "Statistics of sent MLD snooping packets.";

             uses mld-snooping-statistics;
           }
         }
       }
    }
  }//mld-snooping-interface-statistics-attributes

  augment "/rt:routing/rt:control-plane-protocols"+
        "/rt:control-plane-protocol" {

    description
      "IGMP & MLD snooping augmentation to control plane protocol
       configuration and state.";

    /*
      * igmp-snooping-instance
      */

    container igmp-snooping-instance {
      when 'derived-from-or-self(../rt:type, "ims:igmp-snooping")' {
        description
          "This container is only valid for IGMP snooping.";
      }
      if-feature feature-igmp-snooping;
      description
        "IGMP snooping instance to configure the igmp-snooping.";

      leaf scenario {
        type snooping-scenario-type;
        default bridge;
        description
          "The scenario indicates BRIDGE or L2VPN.";
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      }

      uses instance-config-attributes-igmp-snooping;

      uses instance-state-attributes-igmp-snooping;

      uses igmp-snooping-interface-statistics-attributes;

    } //igmp-snooping-instance

    /*
      * mld-snooping-instance
      */

    container mld-snooping-instance {
      when 'derived-from-or-self(../rt:type, "ims:mld-snooping")' {
        description
          "This container is only valid for MLD snooping.";
      }
      if-feature feature-mld-snooping;
      description
        "MLD snooping instance to configure the mld-snooping.";

      leaf scenario {
        type snooping-scenario-type;
        default bridge;
        description
          "The scenario indicates BRIDGE or L2VPN.";
      }

      uses instance-config-attributes-mld-snooping;

      uses instance-state-attributes-mld-snooping;

      uses mld-snooping-interface-statistics-attributes;

    }//mld-snooping-instance
  }

  augment "/dot1q:bridges/dot1q:bridge" {
    description
      "Use IGMP & MLD snooping instance in BRIDGE scenario";

    leaf igmp-snooping-instance {
      type igmp-mld-snooping-instance-ref;

      description
        "Configure IGMP snooping instance under bridge view";
    }
    leaf mld-snooping-instance {
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      type igmp-mld-snooping-instance-ref;

      description
        "Configure MLD snooping instance under bridge view";
    }
  }

  augment "/dot1q:bridges/dot1q:bridge"+
    "/dot1q:component/dot1q:bridge-vlan/dot1q:vlan" {
    description
      "Use IGMP & MLD snooping instance in certain VLAN of BRIDGE";

    leaf igmp-snooping-instance {
      type igmp-mld-snooping-instance-ref;

      description
        "Configure IGMP snooping instance under VLAN view";
    }

    leaf mld-snooping-instance {
      type igmp-mld-snooping-instance-ref;

      description
        "Configure MLD snooping instance under VLAN view";
    }
  }

  augment "/ni:network-instances/ni:network-instance"+
    "/ni:ni-type/l2vpn:l2vpn" {

    description
      "Use IGMP & MLD snooping instance in L2VPN scenario";

    leaf igmp-snooping-instance {
      type igmp-mld-snooping-instance-ref;

      description
        "Configure IGMP snooping instance in L2VPN scenario";
    }
    leaf mld-snooping-instance {
      type igmp-mld-snooping-instance-ref;

      description
        "Configure MLD snooping instance in L2VPN scenario";
    }
  }

  /*  RPCs  */

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  rpc clear-igmp-snooping-groups {
    if-feature rpc-clear-groups;
    description
      "Clear the specified IGMP snooping cache tables.";

    input {

      leaf name {
        if-feature feature-igmp-snooping;
        type igmp-mld-snooping-instance-ref;
        description
          "Name of the igmp-snooping-instance";
      }

      leaf group {
        type rt-types:ipv4-multicast-group-address;
        description
          "Multicast group IPv4 address. If it is not specified,
           all IGMP snooping group tables are cleared.";
      }

      leaf source {
        type rt-types:ipv4-multicast-source-address;
        description
          "Multicast source IPv4 address. If it is not specified,
           all IGMP snooping source-group tables are cleared.";
      }
    }
  } // rpc clear-igmp-snooping-groups

  rpc clear-mld-snooping-groups {
    if-feature rpc-clear-groups;
    description
      "Clear the specified MLD snooping cache tables.";

    input {
      leaf name {
        if-feature feature-mld-snooping;
        type igmp-mld-snooping-instance-ref;
        description
          "Name of the mld-snooping-instance";
      }

      leaf group {
        type rt-types:ipv6-multicast-group-address;
        description
          "Multicast group IPv6 address. If it is not specified,
           all MLD snooping group tables are cleared.";
      }

      leaf source {
        type rt-types:ipv6-multicast-source-address;
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        description
          "Multicast source IPv6 address. If it is not specified,
           all MLD snooping source-group tables are cleared.";
      }
    }
  } // rpc clear-mld-snooping-groups
}
<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:/

ims:igmp-snooping-instance

ims:mld-snooping-instance

The subtrees under /dot1q:bridges/dot1q:bridge

ims:igmp-snooping-instance

ims:mld-snooping-instance

The subtrees under /dot1q:bridges/dot1q:bridge/dot1q:component
/dot1q:bridge-vlan/dot1q:vlan

ims:igmp-snooping-instance

ims:mld-snooping-instance

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Unauthorized access to any data node of these subtrees can adversely
affect the IGMP & MLD Snooping 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:/

ims:igmp-snooping-instance

ims:mld-snooping-instance

Unauthorized access to any data node of these subtrees can disclose the
operational state information of IGMP & MLD Snooping on this device.

Some of the RPC operations in this YANG module may be considered
sensitive or vulnerable in some network environments. It is thus
important to control access to these operations. These are the
operations and their sensitivity/vulnerability:

ims:clear-igmp-snooping-groups

ims:clear-mld-snooping-groups

The IGMP & MLD Snooping YANG module supports the "clear-igmp-snooping-
groups" and "clear-mld-snooping-groups" RPCs. If it meets unauthorized
RPC operation invocation, the IGMP and MLD Snooping group tables will be
cleared unexpectedly.

6. IANA Considerations

RFC Ed.: In this section, replace all occurrences of 'XXXX' with the
actual RFC number (and remove this note).

This document registers the following namespace URIs in the IETF XML

registry [RFC3688]:

--------------------------------------------------------------------
URI: urn:ietf:params:xml:ns:yang:ietf-igmp-mld-snooping
Registrant Contact: The IETF.
XML: N/A, the requested URI is an XML namespace.
--------------------------------------------------------------------
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This document registers the following YANG modules in the YANG Module
Names registry [RFC7950]:
--------------------------------------------------------------------
name:         ietf-igmp-mld-snooping
namespace:    urn:ietf:params:xml:ns:yang:ietf-igmp-mld-snooping
prefix:       ims
reference:    RFC XXXX
--------------------------------------------------------------------

7. References

7.1. Normative References

   [dot1Qcp] IEEE, "Standard for Local and metropolitan area networks--
             Bridges and Bridged Networks--Amendment 30: YANG Data
             Model", IEEE Std 802.1Qcp-2018 (Revision of IEEE Std
             802.1Q-2014), September 2018,
             <https://ieeexplore.ieee.org/servlet/opac?punumber=8467505>

   [RFC1112] Deering, S., "Host extensions for IP multicasting", STD 5,
             RFC 1112, August 1989.

   [RFC2236] W. Fenner, "Internet Group Management Protocol, Version 2",
             RFC 2236, November 1997.

   [RFC2710] Deering, S., Fenner, W., and B. Haberman, "Multicast
             Listener Discovery (MLD) for IPv6", RFC 2710, October 1999.

   [RFC3376] Cain, B., Deering, S., Kouvelas, I., Fenner, B., and A.
             Thyagarajan, "Internet Group Management Protocol, Version
             3", RFC 3376, October 2002.

   [RFC3688] Mealling, M., "The IETF XML Registry", RFC 3688, January
             2004.

   [RFC3810] Vida, R. and L. Costa, "Multicast Listener Discovery
             Version 2 (MLDv2) for IPv6", RFC 3810, June 2004.

   [RFC4286] B. Haberman and J. Martin, "Multicast Router Discovery",
             RFC 4286, December 2005.

   [RFC4541] M. Christensen, K. Kimball, F. Solensky, "Considerations
             for Internet Group Management Protocol (IGMP) and Multicast
             Listener Discovery (MLD) Snooping Switches", RFC 4541, May
             2006.

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   [RFC4604] Holbrook, H., Cain, B., and B. Haberman, "Using Internet
             Group Management Protocol Version 3 (IGMPv3) and Multicast
             Listener Discovery Protocol Version 2 (MLDv2) for Source-
             Specific Multicast", RFC 4604, August 2006.

   [RFC4607] Holbrook, H. and B. Cain, "Source-Specific Multicast for
             IP", RFC 4607, August 2006.

   [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
             the Network Configuration Protocol (NETCONF)", RFC 6020,
             October 2010.

   [RFC6241] R. Enns, Ed., M. Bjorklund, Ed., J. Schoenwaelder, Ed., A.
             Bierman, Ed., "Network Configuration Protocol (NETCONF)",
             RFC 6241, June 2011.

   [RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure
             Shell (SSH)", RFC 6242, June 2011.

   [RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types", RFC 6991,
             July 2013.

   [RFC7950] M. Bjorklund, Ed., "The YANG 1.1 Data Modeling Language",
             RFC 7950, August 2016.

   [RFC8040] A. Bierman, M. Bjorklund, K. Watsen, "RESTCONF Protocol",
             RFC 8040, January 2017.

   [RFC8294] X. Liu, Y. Qu, A. Lindem, C. Hopps, L. Berger, "Common YANG
             Data Types for the Routing Area", RFC 8294, December 2017.

   [RFC8340] M. Bjorklund, and L. Berger, Ed., "YANG Tree Diagrams", RFC
             8340, March 2018.

   [RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration Access
             Control Model", RFC 8341, March 2018.

   [RFC8342] M. Bjorklund and J. Schoenwaelder, "Network Management
             Datastore Architecture (NMDA)", RFC 8342, March 2018.

   [RFC8343] M. Bjorklund, "A YANG Data Model for Interface Management",
             RFC 8343, March 2018.

   [RFC8349] L. Lhotka, A. Lindem, Y. Qu, "A YANG Data Model for Routing
             Management (NMDA Version)", RFC 8349, March 2018.

   [RFC8407] A. Bierman, "Guidelines for Authors and Reviewers of
             Documents Containing YANG Data Models", RFC 8407, October
             2018.

   [RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
             Version 1.3", RFC 8446, August 2018.
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   [RFC8529] L. Berger, C. Hopps, A. Lindem, D. Bogdanovic, X. Liu,
             "YANG Data Model for Network Instances", RFC 8529, March
             2019.

   [RFC8652] X. Liu, F. Guo, M. Sivakumar, P. McAllister, A. Peter, "A
             YANG Data Model for the Internet Group Management Protocol
             (IGMP) and Multicast Listener Discovery (MLD)", RFC 8652,
             November 2019.

   [draft-ietf-bess-l2vpn-yang] Shah, H., Brissette, P., Chen, I.,
             Hussain, I., Wen, B., and K. Tiruveedhula, "YANG Data Model
             for MPLS-basedL2VPN", draft-ietf-bess-l2vpn-yang-10 (work
             in progress), July 2019.

7.2. Informative References

   [RFC3916] X. Xiao, Ed., D. McPherson, Ed., P. Pate, Ed.,
             "Requirements for Pseudo-Wire Emulation Edge-to-Edge
             (PWE3)", RFC 3916, September 2004.

   [RFC6636] H. Asaeda, H. Liu, Q. Wu, "Tuning the Behavior of the
             Internet Group Management Protocol (IGMP) and Multicast
             Listener Discovery (MLD) for Routers in Mobile and Wireless
             Networks", RFC 6636, May 2012.

   [RFC7951] L. Lhotka, "JSON Encoding of Data Modeled with YANG", RFC
             7951, August 2016.

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Appendix A.  Data Tree Example

A.1 Bridge scenario

This section contains an example for bridge scenario in the JSON
encoding [RFC7951], containing both configuration and state data.

              +-----------+
              +  Source   +
              +-----+-----+
                    |
   -----------------+----------------------------
                    |eth1/1
                +---+---+
                +  R1   +
                +-+---+-+
           eth1/2 |    \ eth1/3
                  |     \
                  |      \
                  |       \
                  |        \
           eth2/1 |         \ eth3/1
              +---+---+    +--+---+
              +  R2   +    +  R3  +
              +---+---+    +--+---+
           eth2/2 |          | eth3/2
                  |          |
   ---------------+----------+-------------------
                  |          |
                  |          |
         +--------+--+   +---+--------+
         + Receiver1 +   +  Receiver2 +
         +-----------+   +------------+

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

{
"ietf-interfaces:interfaces":{
  "interface":[
   {
    "name":"eth1/1",
    "type":"iana-if-type:ethernetCsmacd"
   }
  ]
 },
 "ietf-routing:routing":{
  "control-plane-protocols":{
   "control-plane-protocol":[
    {
     "type":"ietf-igmp-mld-snooping:igmp-snooping",
     "name":"bis1",
     "ietf-igmp-mld-snooping:igmp-snooping-instance":{
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       "scenario":"ietf-igmp-mld-snooping:bridge",
       "enable":true
     }
    }
   ]
  }
 },
 "ieee802-dot1q-bridge:bridges":{
  "bridge":[
   {
    "name":"isp1",
    "address":"00-23-ef-a5-77-12",
    "bridge-type":"ieee802-dot1q-bridge:customer-vlan-bridge",
    "component":[
     {
      "name":"comp1",
      "type":"ieee802-dot1q-bridge:c-vlan-component",
      "bridge-vlan":{
       "vlan":[
        {
         "vid":101,
         "ietf-igmp-mld-snooping:igmp-snooping-instance":"bis1"
        }
       ]
      }
     }
    ]
   }
  ]
 }
}

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

{
 "ietf-interfaces:interfaces": {
  "interface": [
   {
    "name": "eth1/1",
    "type": "iana-if-type:ethernetCsmacd",
    "oper-status": "up",
    "statistics": {
     "discontinuity-time": "2018-05-23T12:34:56-05:00"
    }
   }
  ]
 },
 "ietf-routing:routing": {
  "control-plane-protocols": {
   "control-plane-protocol": [
    {
     "type": "ietf-igmp-mld-snooping:igmp-snooping",
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     "name": "bis1",
     "ietf-igmp-mld-snooping:igmp-snooping-instance": {
      "scenario": "ietf-igmp-mld-snooping:bridge",
      "enable": true
     }
    }
   ]
  }
 },
 "ieee802-dot1q-bridge:bridges": {
  "bridge": [
   {
    "name": "isp1",
    "address": "00-23-ef-a5-77-12",
    "bridge-type": "ieee802-dot1q-bridge:customer-vlan-bridge",
    "component": [
     {
      "name": "comp1",
      "type": "ieee802-dot1q-bridge:c-vlan-component",
      "bridge-vlan": {
       "vlan": [
        {
         "vid": 101,
         "ietf-igmp-mld-snooping:igmp-snooping-instance": "bis1"
        }
       ]
      }
     }
    ]
   }
  ]
 }
}

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  A.2 L2VPN scenario

This section contains an example for L2VPN scenario in the JSON encoding
[RFC7951], containing both configuration and state data.

              +-----------+
              +  Source   +
              +-----+-----+
                    |
   -----------------+----------------------------
                    |eth1/1
                +---+---+
                +  R1   +
                +-+---+-+
           eth1/2 |    \ eth1/3
                  |     \
                  |      \
                  |       \
                  |        \
           eth2/1 |         \ eth3/1
              +---+---+    +-+---+
              +  R2   +----+ R3  +
              +---+---+    +-+---+
           eth2/2 |          | eth3/2
                  |          |
   ---------------+----------+-------------------
                  |          |
                  |          |
         +--------+--+   +---+--------+
         + Receiver1 +   +  Receiver2 +
         +-----------+   +------------+

The configuration data for R1 in the above figure could be as follows:
{
"ietf-interfaces:interfaces":{
  "interface":[
   {
    "name":"eth1/1",
    "type":"iana-if-type:ethernetCsmacd"
   }
  ]
 },
 "ietf-pseudowires:pseudowires": {
  "pseudowire": [
   {
    "name": "pw2"
   },
   {
    "name": "pw3"
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   }
  ]
 },
 "ietf-network-instance:network-instances": {
  "network-instance": [
   {
    "name": "vpls1",
    "ietf-igmp-mld-snooping:igmp-snooping-instance": "vis1",
    "ietf-l2vpn:type": "ietf-l2vpn:vpls-instance-type",
    "ietf-l2vpn:signaling-type": "ietf-l2vpn:ldp-signaling",
    "ietf-l2vpn:endpoint": [
     {
      "name": "acs",
      "ac": [
        {
         "name": "eth1/1"
        }
      ]
     },
     {
      "name": "pws",
      "pw": [
        {
         "name": "pw2"
        },
        {
         "name": "pw3"
        }
      ]
     }
    ]
   }
  ]
 },
 "ietf-routing:routing": {
  "control-plane-protocols": {
   "control-plane-protocol": [
    {
     "type": "ietf-igmp-mld-snooping:igmp-snooping",
     "name": "vis1",
     "ietf-igmp-mld-snooping:igmp-snooping-instance": {
      "scenario": "ietf-igmp-mld-snooping:l2vpn",
      "enable": true
     }
    }
   ]
  }
 }
}

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

{
"ietf-interfaces:interfaces":{
  "interface":[
   {
    "name":"eth1/1",
    "type":"iana-if-type:ethernetCsmacd",
    "oper-status": "up",
    "statistics": {
     "discontinuity-time": "2018-05-23T12:34:56-05:00"
    }
   }
  ]
 },
 "ietf-pseudowires:pseudowires": {
  "pseudowire": [
   {
    "name": "pw2"
   },
   {
    "name": "pw3"
   }
  ]
 },
 "ietf-network-instance:network-instances": {
  "network-instance": [
   {
    "name": "vpls1",
    "ietf-igmp-mld-snooping:igmp-snooping-instance": "vis1",
    "ietf-l2vpn:type": "ietf-l2vpn:vpls-instance-type",
    "ietf-l2vpn:signaling-type": "ietf-l2vpn:ldp-signaling",
    "ietf-l2vpn:endpoint": [
     {
      "name": "acs",
      "ac": [
        {
         "name": "eth1/1"
        }
      ]
     },
     {
      "name": "pws",
      "pw": [
        {
         "name": "pw2"
        },
        {
         "name": "pw3"
        }
      ]
     }
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    ]
   }
  ]
 },
 "ietf-routing:routing": {
  "control-plane-protocols": {
   "control-plane-protocol": [
    {
     "type": "ietf-igmp-mld-snooping:igmp-snooping",
     "name": "vis1",
     "ietf-igmp-mld-snooping:igmp-snooping-instance": {
      "scenario": "ietf-igmp-mld-snooping:l2vpn",
      "enable": true
     }
    }
   ]
  }
 }
}

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Authors' Addresses

   Hongji Zhao
   Ericsson (China) Communications Company Ltd.
   Ericsson Tower, No. 5 Lize East Street,
   Chaoyang District Beijing 100102, P.R. China

   Email: hongji.zhao@ericsson.com

   Xufeng Liu
   Volta Networks
   USA

   EMail: xufeng.liu.ietf@gmail.com

   Yisong Liu
   China Mobile
   China

   Email: liuyisong@chinamobile.com

   Anish Peter
   Individual

   EMail: anish.ietf@gmail.com

   Mahesh Sivakumar
   Juniper Networks
   1133 Innovation Way
   Sunnyvale, California
   USA

   EMail: sivakumar.mahesh@gmail.com

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