PIM Working Group                                                X. Liu
Internet-Draft                                                    Jabil
Intended Status: Standard Track                                  F. Guo
Expires: April 20, 2018                                          Huawei
                                                           M. Sivakumar
                                                                  Cisco
                                                          P. McAllister
                                                    Metaswitch Networks
                                                               A. Peter
                                                       Juniper Networks
                                                           Oct 20, 2017


    A YANG data model for Internet Group Management Protocol (IGMP) and
                    Multicast Listener Discovery (MLD)
                      draft-ietf-pim-igmp-mld-yang-06


Status of this Memo

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   This Internet-Draft will expire on April 20, 2018.

Copyright Notice

   Copyright (c) 2017 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



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   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.

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) devices.

Table of Contents


   1. Introduction ................................................ 2
      1.1. Requirements Language................................... 3
      1.2. Terminology ............................................ 3
   2. Design of Data model......................................... 3
      2.1. Scope of model ......................................... 3
      2.2. Optional capabilities................................... 3
      2.3. Position of address family in hierarchy................. 4
   3. Module Structure ............................................ 4
      3.1. IGMP Configuration and Operational state................ 4
      3.2. MLD Configuration and Operational State................. 6
      3.3. IGMP and MLD RPC........................................ 8
   4. IGMP and MLD YANG Modules.................................... 9
   5. Security Considerations..................................... 32
   6. IANA Considerations ........................................ 32
   7. Acknowledgments ............................................ 33
   8. Contributing Authors........................................ 33
   9. References ................................................. 33
      9.1. Normative References................................... 33
      9.2. Informative References................................. 34

1. Introduction

   YANG [RFC6020] [RFC7950] is a data definition language that was
   introduced to model the configuration and running state of a device
   managed using NETCONF [RFC6241].  YANG is now also being used as a
   component of wider management interfaces, such as CLIs.

   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) devices. This model will support
   the core IGMP and MLD protocols, as well as many other features
   mentioned in separate IGMP and MLD RFCs. Non-core features are
   defined as optional in the provided data model.



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1.1. Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC-2119 [RFC2119].

1.2. Terminology

   The terminology for describing YANG data models is found in
   [RFC6020] [RFC7950].

   This document employs YANG tree diagrams, which are explained in [I-
   D.ietf-netmod-rfc6087bis].

2. Design of Data model

2.1. Scope of model

   The model covers IGMPv1 [RFC1112], IGMPv2 [RFC2236], IGMPv3
   [RFC3376] and MLDv1 [RFC2710], MLDv2 [RFC3810].

   The configuration of IGMP and MLD features, and the operational
   state fields and RPC definitions are not all included in this
   document of the data model. This model can be extended, though the
   structure of what has been written may be taken as representative of
   the structure of the whole model.

   This model does not cover other IGMP and MLD related protocols such
   as IGMP/MLD Proxy [RFC4605] or IGMP/MLD Snooping [RFC4541] etc.,
   these will be specified in separate documents.

2.2. Optional capabilities

   This model is designed to represent the capabilities of IGMP and MLD
   devices with various specifications, including some with basic
   subsets of the IGMP and MLD protocols.  The main design goals of
   this document are that any major now-existing implementation may be
   said to support the basic model, and that the configuration of all
   implementations meeting the specification is easy to express through
   some combination of the features in the basic model and simple
   vendor augmentations.

   There is also value in widely-supported features being standardized,
   to save work for individual vendors, and so that mapping between
   different vendors' configuration is not needlessly complicated.
   Therefore these modules declare 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 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.

   For the same reason, wide constant ranges (for example, timer
   maximum and minimum) will be used in the model.  It is expected that
   vendors will augment the model with any specific restrictions that
   might be required. Vendors may also extend the features list with
   proprietary extensions.

2.3. Position of address family in hierarchy

   The current document contains IGMP and MLD as separate schema
   branches in the structure. The reason for this is to make it easier
   for implementations which may optionally choose to support specific
   address families. And the names of objects may be different between
   the IPv4 (IGMP) and IPv6 (MLD) address families.

3. Module Structure

3.1. IGMP Configuration and Operational state

   The IGMP YANG model follows the Guidelines for YANG Module Authors
   (NMDA) [draft-dsdt-nmda-guidelines-01]. The IGMP module defines the
   routing-control-plane-protocol-wide configuration and operational
   state options separately in a three-level hierarchy as listed below:

       Global level: IGMP configuration and operational state attributes
   for the entire routing system.

       Interface-global: Only including configuration data nodes now.
   IGMP configuration attributes are applicable to all the interfaces
   whose interface-level corresponding attributes are not existing,
   with same attributes' value for these interfaces.

       Interface-level: IGMP configuration and operational state
   attributes specific to the given interface.

   Where fields are not genuinely essential to protocol operation, they
   are marked as optional. Some fields will be essential but have a
   default specified, so that they need not be configured explicitly.


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   We define the IGMP model as a protocol-centric model , and the IGMP
   model augments "/rt:routing/rt:control-plane-protocols/ rt:control-
   plane-protocol" in [draft-acee-netmod-rfc8022bis-01] and would allow
   a single protocol instance per VRF.

   augment /rt:routing/rt:control-plane-protocols/rt:control-plane-protocol:
       +--rw igmp
          +--rw global
          |  +--rw enable?          boolean {global-admin-enable}?
          |  +--rw max-entries?     uint32 {global-max-entries}?
          |  +--rw max-groups?      uint32 {global-max-groups}?
          |  +--ro entries-count?   uint32
          |  +--ro groups-count?    uint32
          |  +--ro statistics
          |     +--ro discontinuity-time?   yang:date-and-time
          |     +--ro error
          |     |  +--ro total?       yang:counter64
          |     |  +--ro query?       yang:counter64
          |     |  +--ro report?      yang:counter64
          |     |  +--ro leave?       yang:counter64
          |     |  +--ro checksum?    yang:counter64
          |     |  +--ro too-short?   yang:counter64
          |     +--ro received
          |     |  +--ro total?    yang:counter64
          |     |  +--ro query?    yang:counter64
          |     |  +--ro report?   yang:counter64
          |     |  +--ro leave?    yang:counter64
          |     +--ro sent
          |        +--ro total?    yang:counter64
          |        +--ro query?    yang:counter64
          |        +--ro report?   yang:counter64
          |        +--ro leave?    yang:counter64
          +--rw interfaces
             +--rw last-member-query-interval?   uint16
             +--rw max-groups-per-interface?     uint32 {intf-max-groups}?
             +--rw query-interval?               uint16
             +--rw query-max-response-time?      uint16
             +--rw require-router-alert?         boolean {intf-require-router-alert}?
             +--rw robustness-variable?          uint8
             +--rw version?                      uint8
             +--rw interface* [interface-name]
                +--rw interface-name                if:interface-ref
                +--rw enable?                       boolean {intf-admin-enable}?
                +--rw group-policy?                 string
                +--rw immediate-leave?              empty {intf-immediate-leave}?
                +--rw last-member-query-interval?   uint16
                +--rw max-groups?                   uint32 {intf-max-groups}?
                +--rw max-group-sources?            uint32 {intf-max-group-sources}?
                +--rw query-interval?               uint16


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                +--rw query-max-response-time?      uint16
                +--rw require-router-alert?         boolean {intf-require-router-alert}?
                +--rw robustness-variable?          uint8
                +--rw source-policy?                string {intf-source-policy}?
                +--rw verify-source-subnet?         empty {intf-verify-source-subnet}?
                +--rw explicit-tracking?            boolean {intf-explicit-tracking}?
                +--rw exclude-lite?                 boolean {intf-exclude-lite}?
                +--rw version?                      uint8
                +--rw join-group*                   inet:ipv4-address {intf-join-group}?
                +--rw ssm-map* [source-addr group-policy] {intf-ssm-map}?
                |  +--rw source-addr     ssm-map-ipv4-addr-type
                |  +--rw group-policy    string
                +--rw static-group* [group-addr source-addr] {intf-static-group}?
                |  +--rw group-addr     inet:ipv4-address
                |  +--rw source-addr    source-ipv4-addr-type
                +--ro oper-status?                  enumeration
                +--ro querier?                      inet:ipv4-address
                +--ro joined-group*                 inet:ipv4-address {intf-join-group}?
                +--ro group* [group-address]
                   +--ro group-address    inet:ipv4-address
                   +--ro expire?          uint32
                   +--ro filter-mode?     enumeration
                   +--ro up-time?         uint32
                   +--ro last-reporter?   inet:ipv4-address
                   +--ro source* [source-address]
                      +--ro source-address    inet:ipv4-address
                      +--ro expire?           uint32
                      +--ro up-time?          uint32
                      +--ro host-count?       uint32 {intf-explicit-tracking}?
                      +--ro last-reporter?    inet:ipv4-address
                      +--ro host* [host-address] {intf-explicit-tracking}?
                         +--ro host-address        inet:ipv4-address
                         +--ro host-filter-mode?   enumeration


3.2. MLD Configuration and Operational State

   The MLD YANG model uses the same structure as IGMP YANG model. The
   MLD module also defines the routing-control-plane-protocol-wide
   configuration and operational state options separately in a three-
   level hierarchy.

   augment /rt:routing/rt:control-plane-protocols/rt:control-plane-protocol:
       +--rw mld
          +--rw global
          |  +--rw enable?          boolean {global-admin-enable}?
          |  +--rw max-entries?     uint32 {global-max-entries}?
          |  +--rw max-groups?      uint32 {global-max-groups}?
          |  +--ro entries-count?   uint32


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          |  +--ro groups-count?    uint32
          |  +--ro statistics
          |     +--ro discontinuity-time?   yang:date-and-time
          |     +--ro error
          |     |  +--ro total?       yang:counter64
          |     |  +--ro query?       yang:counter64
          |     |  +--ro report?      yang:counter64
          |     |  +--ro leave?       yang:counter64
          |     |  +--ro checksum?    yang:counter64
          |     |  +--ro too-short?   yang:counter64
          |     +--ro received
          |     |  +--ro total?    yang:counter64
          |     |  +--ro query?    yang:counter64
          |     |  +--ro report?   yang:counter64
          |     |  +--ro leave?    yang:counter64
          |     +--ro sent
          |        +--ro total?    yang:counter64
          |        +--ro query?    yang:counter64
          |        +--ro report?   yang:counter64
          |        +--ro leave?    yang:counter64
          +--rw interfaces
             +--rw last-member-query-interval?   uint16
             +--rw max-groups-per-interface?     uint32 {intf-max-groups}?
             +--rw query-interval?               uint16
             +--rw query-max-response-time?      uint16
             +--rw require-router-alert?         boolean {intf-require-router-alert}?
             +--rw robustness-variable?          uint8
             +--rw version?                      uint8
             +--rw interface* [interface-name]
                +--rw interface-name                if:interface-ref
                +--rw enable?                       boolean {intf-admin-enable}?
                +--rw group-policy?                 string
                +--rw immediate-leave?              empty {intf-immediate-leave}?
                +--rw last-member-query-interval?   uint16
                +--rw max-groups?                   uint32 {intf-max-groups}?
                +--rw max-group-sources?            uint32 {intf-max-group-sources}?
                +--rw query-interval?               uint16
                +--rw query-max-response-time?      uint16
                +--rw require-router-alert?         boolean {intf-require-router-alert}?
                +--rw robustness-variable?          uint8
                +--rw source-policy?                string {intf-source-policy}?
                +--rw verify-source-subnet?         empty {intf-verify-source-subnet}?
                +--rw explicit-tracking?            boolean {intf-explicit-tracking}?
                +--rw exclude-lite?                 boolean {intf-exclude-lite}?
                +--rw version?                      uint8
                +--rw join-group*                   inet:ipv6-address {intf-join-group}?
                +--rw ssm-map* [source-addr group-policy] {intf-ssm-map}?
                |  +--rw source-addr     ssm-map-ipv6-addr-type
                |  +--rw group-policy    string


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                +--rw static-group* [group source-addr] {intf-static-group}?
                |  +--rw group          inet:ipv6-address
                |  +--rw source-addr    source-ipv6-addr-type
                +--ro oper-status?                  enumeration
                +--ro querier?                      inet:ipv6-address
                +--ro joined-group*                 inet:ipv6-address {intf-join-group}?
                +--ro group* [group-address]
                   +--ro group-address    inet:ipv6-address
                   +--ro expire?          uint32
                   +--ro filter-mode?     enumeration
                   +--ro up-time?         uint32
                   +--ro last-reporter?   inet:ipv6-address
                   +--ro source* [source-address]
                      +--ro source-address    inet:ipv6-address
                      +--ro expire?           uint32
                      +--ro up-time?          uint32
                      +--ro host-count?       uint32 {intf-explicit-tracking}?
                      +--ro last-reporter?    inet:ipv6-address
                      +--ro host* [host-address] {intf-explicit-tracking}?
                         +--ro host-address        inet:ipv6-address
                         +--ro host-filter-mode?   enumeration


3.3. IGMP and MLD RPC

   IGMP and MLD RPC clears the specified IGMP and MLD group membership.

   rpcs:

       +---x clear-igmp-groups {rpc-clear-groups}?

       |  +---w input

       |     +---w interface?   string

       |     +---w group?       inet:ipv4-address

       |     +---w source?      inet:ipv4-address

       +---x clear-mld-groups {rpc-clear-groups}?

          +---w input

             +---w interface?   string

             +---w group?       inet:ipv6-address

             +---w source?      inet:ipv6-address



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4. IGMP and MLD YANG Modules

   <CODE BEGINS> file "ietf-igmp-mld@2017-10-20.yang"
   module ietf-igmp-mld {
      namespace "urn:ietf:params:xml:ns:yang:ietf-igmp-mld";
      // replace with IANA namespace when assigned
      prefix igmp-mld;

      import ietf-inet-types {
        prefix "inet";
      }

      import ietf-yang-types {
        prefix "yang";
      }

      import ietf-routing {
        prefix "rt";
      }

      import ietf-interfaces {
        prefix "if";
      }

      import ietf-ip {
        prefix ip;
      }

      organization
        "IETF PIM Working Group";

      contact
        "WG Web:   <http://tools.ietf.org/wg/pim/>
         WG List:  <mailto:pim@ietf.org>

         WG Chair: Stig Venaas
                   <mailto:stig@venaas.com>

         WG Chair: Mike McBride
                   <mailto:mmcbride7@gmail.com>

         Editor:   Xufeng Liu
                   <mailto:Xufeng_Liu@jabil.com>

         Editor:   Feng Guo
                   <mailto:guofeng@huawei.com>



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         Editor:   Mahesh Sivakumar
                   <mailto:masivaku@cisco.com>

         Editor:   Pete McAllister
                   <mailto:pete.mcallister@metaswitch.com>

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

      description
        "The module defines a collection of YANG definitions common for
        IGMP and MLD.";

      revision 2017-10-20 {
        description
          "Updated yang data model for adding explicit-tracking and
           lightweight IGMPv3 and MLDv2 function.";
        reference
          "RFC XXXX: A YANG Data Model for IGMP and MLD";
      }

      revision 2017-09-19 {
        description
          "Updated yang data model for NMDA version and errata.";
        reference
          "RFC XXXX: A YANG Data Model for IGMP and MLD";
      }

      /*
       * Features
       */
      feature global-admin-enable {
        description
          "Support global configuration to enable or disable protocol.";
      }

      feature global-interface-config {
        description
          "Support global configuration applied for all interfaces.";
      }

      feature global-max-entries {
        description
          "Support configuration of global max-entries.";
      }

      feature global-max-groups {
        description
          "Support configuration of global max-groups.";


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      }

      feature intf-admin-enable {
        description
          "Support configuration of interface administrative enabling.";
      }

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

      feature intf-join-group {
        description
          "Support configuration of interface join-group.";
      }

      feature intf-max-groups {
        description
          "Support configuration of interface max-groups.";
      }

      feature intf-max-group-sources {
        description
          "Support configuration of interface max-group-sources.";
      }

      feature intf-require-router-alert {
        description
          "Support configuration of interface require-router-alert.";
      }

      feature intf-source-policy {
        description
          "Support configuration of interface source policy.";
      }

      feature intf-ssm-map {
        description
          "Support configuration of interface ssm-map.";
      }

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

      feature intf-verify-source-subnet {
        description


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          "Support configuration of interface verify-source-subnet.";
      }

      feature intf-explicit-tracking {
        description
          "Support configuration of interface explicit-tracking hosts.";
      }

      feature intf-exclude-lite {
        description
          "Support configuration of interface exclude-lite.";
      }

      feature per-interface-config {
        description
          "Support per interface configuration.";
      }

      feature rpc-clear-groups {
        description
          "Support rpc's to clear groups.";
      }

      /*
       * Typedefs
       */
      typedef ssm-map-ipv4-addr-type {
        type union {
          type enumeration {
            enum 'policy' {
              description
              "Source address is specified in SSM map policy.";
            }
          }
          type inet:ipv4-address;
        }
        description
          "Multicast source IP address type for SSM map.";
      } // source-ipv4-addr-type

      typedef ssm-map-ipv6-addr-type {
        type union {
          type enumeration {
            enum 'policy' {
              description
              "Source address is specified in SSM map policy.";
            }
          }
          type inet:ipv6-address;


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        }
        description
          "Multicast source IP address type for SSM map.";
      } // source-ipv6-addr-type

      typedef source-ipv4-addr-type {
        type union {
          type enumeration {
            enum '*' {
              description
              "Any source address.";
            }
          }
          type inet:ipv4-address;
        }
        description
          "Multicast source IP address type.";
      } // source-ipv4-addr-type

      typedef source-ipv6-addr-type {
        type union {
          type enumeration {
            enum '*' {
              description
              "Any source address.";
            }
          }
          type inet:ipv6-address;
        }
        description
          "Multicast source IP address type.";
      } // source-ipv6-addr-type

      /*
       * Identities
       */

      /*
       * Groupings
       */
      grouping global-config-attributes {
        description "Global IGMP and MLD configuration.";

        leaf enable {
          if-feature global-admin-enable;
          type boolean;
          description
            "true to enable IGMP or MLD in the routing instance;
             false to disable IGMP or MLD in the routing instance.";


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        }

        leaf max-entries {
          if-feature global-max-entries;
          type uint32;
          description
            "The maximum number of entries in IGMP or MLD.";
        }
        leaf max-groups {
          if-feature global-max-groups;
          type uint32;
          description
            "The maximum number of groups that IGMP
             or MLD can join.";
        }
      } // global-config-attributes

      grouping global-state-attributes {

        description "Global IGMP and MLD state attributes.";

        leaf entries-count {
          type uint32;
          config false;
          description
            "The number of entries in IGMP or MLD.";
        }
        leaf groups-count {
          type uint32;
          config false;
          description
            "The number of groups that IGMP or MLD can join.";
        }

        container statistics {
          config false;
          description "Global statistics.";

          leaf discontinuity-time {
            type yang:date-and-time;
            description
              "The time on the most recent occasion at which any one
              or more of the statistic counters suffered a
              discontinuity. If no such discontinuities have occurred
              since the last re-initialization of the local
              management subsystem, then this node contains the time
              the local management subsystem re-initialized itself.";
          }



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          container error {
            description "Statistics of errors.";
            uses global-statistics-error;
          }

          container received {
            description "Statistics of received messages.";
            uses global-statistics-sent-received;
          }
          container sent {
            description "Statistics of sent messages.";
            uses global-statistics-sent-received;
          }
        } // statistics
      } // global-state-attributes

      grouping global-statistics-error {
        description
          "A grouping defining statistics attributes for errors.";
        uses global-statistics-sent-received;
        leaf checksum {
          type yang:counter64;
          description
            "The number of checksum errors.";
        }
        leaf too-short {
          type yang:counter64;
          description
            "The number of messages that are too short.";
        }
      } // global-statistics-error

      grouping global-statistics-sent-received {
        description
          "A grouping defining statistics attributes.";
        leaf total {
          type yang:counter64;
          description
            "The number of total messages.";
        }
        leaf query {
          type yang:counter64;
          description
            "The number of query messages.";
        }
        leaf report {
          type yang:counter64;
          description
            "The number of report messages.";


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        }
        leaf leave {
          type yang:counter64;
          description
            "The number of leave messages.";
        }
      } // global-statistics-sent-received

      grouping interfaces-config-attributes {
        description
          "Configuration attributes applied to the interfaces whose
           per interface attributes are not existing.";

        leaf last-member-query-interval {
          type uint16 {
            range "1..65535";
          }
          units seconds;
          default 1;
          description
            "Last Member Query Interval, which may be tuned to modify the
             leave latency of the network.";
           reference "RFC3376. Sec. 8.8.";
        }

        leaf max-groups-per-interface {
          if-feature intf-max-groups;
          type uint32;
          description
            "The maximum number of groups that IGMP or MLD can join.";
        }

        leaf query-interval {
          type uint16 {
            range "1..31744";
          }
          units seconds;
          default 125;
          description
            "The Query Interval is the interval between General Queries
             sent by the Querier.";
          reference "RFC3376. Sec. 4.1.7, 8.2, 8.14.2.";
        }

        leaf query-max-response-time {
          type uint16 {
            range "1..65535";
          }
          units seconds;


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          default 10;
          description
            "Query maximum response time specifies the maximum time
             allowed before sending a responding report.";
          reference "RFC3376. Sec. 4.1.1, 8.3, 8.14.3.";
        }

        leaf require-router-alert {
          if-feature intf-require-router-alert;
          type boolean;
          default false;
          description
            "Protocol packets should contain router alert IP option.";
        }

        leaf robustness-variable {
          type uint8 {
            range "2..7";
          }
          default 2;
          description
            "Querier's Robustness Variable allows tuning for the expected
             packet loss on a network.";
          reference "RFC3376. Sec. 4.1.6, 8.1, 8.14.1.";
        }


      } // interfaces-config-attributes

      grouping interfaces-config-attributes-igmp {
        description  "interfaces configuration for IGMP.";

        uses interfaces-config-attributes;
        leaf version {
          type uint8 {
            range "1..3";
          }
          description "IGMP version.";
          reference "RFC1112, RFC2236, RFC3376.";
        }
      }

      grouping interfaces-config-attributes-mld {
        description  "interfaces configuration for MLD.";

        uses interfaces-config-attributes;
        leaf version {
          type uint8 {
            range "1..2";


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          }
          description "MLD version.";
          reference "RFC2710, RFC3810.";
        }
      }

      grouping interface-config-attributes-igmp {
        description "Per interface configuration for IGMP.";

        uses interface-config-attributes-igmp-mld;

        leaf version {
          type uint8 {
            range "1..3";
          }
          description "IGMP version.";
          reference "RFC1112, RFC2236, RFC3376.";
        }
        leaf-list join-group {
          if-feature intf-join-group;
          type inet:ipv4-address;
          description
            "The router joins this multicast group on the interface.";
        }

        list ssm-map {
          if-feature intf-ssm-map;
          key "source-addr group-policy";
          description "The policy for (*,G) mapping to (S,G).";
          leaf source-addr {
            type ssm-map-ipv4-addr-type;
            description
              "Multicast source IP address.";
          }
          leaf group-policy {
            type string;
            description
              "Name of the access policy used to filter IGMP
               membership.A device can restrict the length
               and value of this name, possibly space and special
               characters are not allowed. ";
          }
        }

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


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          leaf group-addr {
            type inet:ipv4-address;
            description
              "Multicast group IP address.";
          }
          leaf source-addr {
            type source-ipv4-addr-type;
            description
              "Multicast source IP address.";
          }
        }
      } // interface-config-attributes-igmp

      grouping interface-config-attributes-igmp-mld {
        description
          "Per interface configuration for both IGMP and MLD.";

        leaf enable {
          if-feature intf-admin-enable;
          type boolean;
          default false;
          description
            "true to enable IGMP or MLD on the interface;
             false to disable IGMP or MLD on the interface.";
        }
        leaf group-policy {
          type string;
          description
            "Name of the access policy used to filter IGMP or MLD
             membership.A device can restrict the length
             and value of this name, possibly space and special
             characters are not allowed.";
        }
        leaf immediate-leave {
          if-feature intf-immediate-leave;
          type empty;
          description
            "If present, IGMP or MLD perform an immediate leave upon
             receiving an IGMPv2 or MLDv1 leave message.
             If the router is IGMP-enabled or MLD-enabled, it sends an
             IGMP or MLD last member query with a last member query
             response time. However, the router does not wait for
             the response time before it prunes off the group.";
        }

        leaf last-member-query-interval {
          type uint16 {
            range "1..65535";


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          }
          units seconds;
          default 1;
          description
            "Last Member Query Interval, which may be tuned to modify the
             leave latency of the network.";
          reference "RFC3376. Sec. 8.8.";
        }

        leaf max-groups {
          if-feature intf-max-groups;
          type uint32;
          description
            "The maximum number of groups that IGMP ro MLD can join.";
        }
        leaf max-group-sources {
          if-feature intf-max-group-sources;
          type uint32;
          description
            "The maximum number of group sources.";
        }

        leaf query-interval {
          type uint16 {
            range "1..31744";
          }
          units seconds;
          default 125;
          description
            "The Query Interval is the interval between General Queries
             sent by the Querier.";
          reference "RFC3376. Sec. 4.1.7, 8.2, 8.14.2.";
        }

        leaf query-max-response-time {
          type uint16 {
            range "1..65535";
          }
          units seconds;
          default 10;
          description
            "Query maximum response time specifies the maximum time
             allowed before sending a responding report.";
          reference "RFC3376. Sec. 4.1.1, 8.3, 8.14.3.";
        }

        leaf require-router-alert {
          if-feature intf-require-router-alert;
          type boolean;


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          description
            "Protocol packets should contain router alert IP option.";
        }

        leaf robustness-variable {
          type uint8 {
            range "2..7";
          }
          default 2;
          description
            "Querier's Robustness Variable allows tuning for the expected
             packet loss on a network.";
          reference "RFC3376. Sec. 4.1.6, 8.1, 8.14.1.";
        }

        leaf source-policy {
          if-feature intf-source-policy;
          type string;
          description
            "Name of the access policy used to filter sources.
             A device can restrict the length
             and value of this name, possibly space and special
             characters are not allowed.";
        }
        leaf verify-source-subnet {
          if-feature intf-verify-source-subnet;
          type empty;
          description
            "If present, the interface accepts packets with matching
             source IP subnet only.";
        }
        leaf explicit-tracking {
          if-feature intf-explicit-tracking;
          type boolean;
          description
            "IGMP/MLD-based explicit membership tracking function
             for multicast routers and IGMP/MLD proxy devices
             supporting IGMPv3/MLDv2. The explicit membership tracking
             function contributes to saving network resources and
             shortening leave latency.";
        }
        leaf exclude-lite {
          if-feature intf-exclude-lite;
          type boolean;
          description
            "lightweight IGMPv3 and MLDv2 protocols, which simplify the
             standard versions of IGMPv3 and MLDv2.";
          reference "RFC5790";
        }


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      } // interface-config-attributes-igmp-mld

      grouping interface-config-attributes-mld {
        description "Per interface configuration for MLD.";

        uses interface-config-attributes-igmp-mld;

        leaf version {
          type uint8 {
            range "1..2";
          }
          description "MLD version.";
          reference "RFC2710, RFC3810.";
        }
        leaf-list join-group {
          if-feature intf-join-group;
          type inet:ipv6-address;
          description
            "The router joins this multicast group on the interface.";
        }

        list ssm-map {
          if-feature intf-ssm-map;
          key "source-addr group-policy";
          description "The policy for (*,G) mapping to (S,G).";
          leaf source-addr {
            type ssm-map-ipv6-addr-type;
            description
              "Multicast source IPv6 address.";
          }
          leaf group-policy {
            type string;
            description
              "Name of the access policy used to filter MLD
               membership.A device can restrict the length
               and value of this name, possibly space and special
               characters are not allowed.";
          }
        }

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

          leaf group {
            type inet:ipv6-address;


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            description
              "Multicast group IPv6 address.";
          }
          leaf source-addr {
            type source-ipv6-addr-type;
            description
              "Multicast source IPv6 address.";
          }
        }
      } // interface-config-attributes-mld

      grouping interface-state-attributes-igmp {

        description
          "Per interface state attributes for IGMP.";

        uses interface-state-attributes-igmp-mld;

        leaf querier {
          type inet:ipv4-address;
          config false;
          description "The querier address in the subnet";
        }
        leaf-list joined-group {
          if-feature intf-join-group;
          type inet:ipv4-address;
          config false;
          description
            "The routers that joined this multicast group.";
        }

        list group {
          key "group-address";
          config false;
          description
            "Multicast group membership information
            that joined on the interface.";

          leaf group-address {
            type inet:ipv4-address;
            description
              "Multicast group address.";
          }
          uses interface-state-group-attributes-igmp-mld;

          leaf last-reporter {
            type inet:ipv4-address;
            description
              "The last host address which has sent the


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               report to join the multicast group.";
          }
          list source {
            key "source-address";
            description
              "List of multicast source information
               of the multicast group.";

            leaf source-address {
              type inet:ipv4-address;
              description
                "Multicast source address";
            }
            uses interface-state-source-attributes-igmp-mld;
            leaf last-reporter {
              type inet:ipv4-address;
              description
                "The last host address which has sent the
                 report to join the multicast source and group.";
            }
            list host {
              if-feature intf-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 enumeration {
                  enum "include" {
                    description
                      "In include mode";
                  }
                  enum "exclude" {
                    description
                      "In exclude mode.";
                  }
                }
                description
                  "Filter mode for a multicast membership
                   host may be either include or exclude.";
              }
            }// list host
          } // list source


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        } // list group
      } // interface-state-attributes-igmp

      grouping interface-state-attributes-igmp-mld {
        description
          "Per interface state attributes for both IGMP and MLD.";

        leaf oper-status {
          type enumeration {
            enum up {
              description
              "Ready to pass packets.";
            }
            enum down {
              description
              "The interface does not pass any packets.";
            }
          }
          config false;
          description
            "interface up or down state for IGMP or MLD protocol";
        }
      } // interface-config-attributes-igmp-mld

      grouping interface-state-attributes-mld {

        description
          "Per interface state attributes for MLD.";

        uses interface-state-attributes-igmp-mld;

        leaf querier {
          type inet:ipv6-address;
          config false;
          description
            "The querier address in the subnet.";
        }
        leaf-list joined-group {
          if-feature intf-join-group;
          type inet:ipv6-address;
          config false;
          description
            "The routers that joined this multicast group.";
        }

        list group {
          key "group-address";
          config false;
          description


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            "Multicast group membership information
            that joined on the interface.";

          leaf group-address {
            type inet:ipv6-address;
            description
              "Multicast group address.";
          }
          uses interface-state-group-attributes-igmp-mld;

          leaf last-reporter {
            type inet:ipv6-address;
            description
              "The last host address which has sent the
               report to join the multicast group.";
          }
          list source {
            key "source-address";
            description
              "List of multicast source information
               of the multicast group.";

            leaf source-address {
              type inet:ipv6-address;
              description
                "Multicast source address";
            }
            uses interface-state-source-attributes-igmp-mld;
            leaf last-reporter {
              type inet:ipv6-address;
              description
                "The last host address which has sent the
                 report to join the multicast source and group.";
            }
            list host {
              if-feature intf-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 enumeration {
                  enum "include" {


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                    description
                      "In include mode";
                  }
                  enum "exclude" {
                    description
                      "In exclude mode.";
                  }
                }
                description
                  "Filter mode for a multicast membership
                   host may be either include or exclude.";
              }
            }// list host
          } // list source
        } // list group
      } // interface-state-attributes-mld

      grouping interface-state-group-attributes-igmp-mld {
        description
          "Per interface state attributes for both IGMP and MLD
           groups.";

        leaf expire {
          type uint32;
          units seconds;
          description
            "The time left before multicast group state expires.";
        }
        leaf filter-mode {
          type enumeration {
            enum "include" {
              description
                "In include mode, reception of packets sent
                 to the specified multicast address is requested
                 only from those IP source addresses listed in the
                 source-list parameter";
            }
            enum "exclude" {
              description
                "In exclude mode, reception of packets sent
                 to the given multicast address is requested
                 from all IP source addresses except those
                 listed in the source-list parameter.";
            }
          }
          description
            "Filter mode for a multicast group,
             may be either include or exclude.";
        }


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        leaf up-time {
          type uint32;
          units seconds;
          description
            "The elapsed time since the device created multicast group record.";
        }
      } // interface-state-group-attributes-igmp-mld

      grouping interface-state-source-attributes-igmp-mld {
        description
          "Per interface state attributes for both IGMP and MLD
           source-group records.";

        leaf expire {
          type uint32;
          units seconds;
          description
            "The time left before multicast source-group state expires.";
        }
        leaf up-time {
          type uint32;
          units seconds;
          description
            "The elapsed time since the device created multicast
             source-group record.";
        }
        leaf host-count {
          if-feature intf-explicit-tracking;
          type uint32;
          description
            "The number of host addresses.";
        }
      } // interface-state-source-attributes-igmp-mld

      /*
       * Configuration and Operational state data nodes (NMDA version)
       */
      augment "/rt:routing/rt:control-plane-protocols/rt:control-plane-protocol"
      {
        description
          "IGMP augmentation to routing control plane protocol
           configuration and state.";

        container igmp {
          description
            "IGMP operational state data.";

          container global {
            description


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              "Global attributes.";
            uses global-config-attributes;
            uses global-state-attributes;
          }

          container interfaces {
            description
              "Containing a list of interfaces.";

            uses interfaces-config-attributes-igmp {
              if-feature global-interface-config;
            }

            list interface {
              key "interface-name";
              description
                "List of IGMP interfaces.";
              leaf interface-name {
                type if:interface-ref;
                must "/if:interfaces/if:interface[if:name = current()]/"
                   + "ip:ipv4" {
                  description
                    "The interface must have IPv4 enabled.";
                }
                description
                  "Reference to an entry in the global interface list.";
              }
              uses interface-config-attributes-igmp {
                if-feature per-interface-config;
              }
              uses interface-state-attributes-igmp;
            } // interface
          } // interfaces
        } // igmp
      }//augment

      augment "/rt:routing/rt:control-plane-protocols/rt:control-plane-protocol"
      {
        description
          "MLD augmentation to routing control plane protocol
           configuration and state.";

        container mld {
          description
            "MLD operational state data.";

          container global {
            description
              "Global attributes.";


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            uses global-config-attributes;
            uses global-state-attributes;
          }

          container interfaces {
            description
              "Containing a list of interfaces.";

            uses interfaces-config-attributes-mld {
              if-feature global-interface-config;
            }

            list interface {
              key "interface-name";
              description
                "List of MLD interfaces.";
              leaf interface-name {
                type if:interface-ref;
                must "/if:interfaces/if:interface[if:name = current()]/"
                   + "ip:ipv6" {
                  description
                    "The interface must have IPv6 enabled.";
                }
                description
                  "Reference to an entry in the global interface list.";
              }
              uses interface-config-attributes-mld {
                if-feature per-interface-config;
              }
              uses interface-state-attributes-mld;
            } // interface
          } // interfaces
        } // mld
      } // augment

      /*
       * RPCs
       */
      rpc clear-igmp-groups {
        if-feature rpc-clear-groups;
        description
          "Clears the specified IGMP cache entries.";

        input {
          leaf interface {
            type string;
            description
              "Name of the IGMP interface.
               If it is not specified, groups from all interfaces are


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

      rpc clear-mld-groups {
        if-feature rpc-clear-groups;
        description
          "Clears the specified MLD cache entires.";

        input {
          leaf interface {
            type string;
            description
              "Name of the MLD interface.
               If it is not specified, groups from all interfaces are
               cleared.";
          }
          leaf group {
            type inet:ipv6-address;
            description
              "Multicast group IPv6 address.
               If it is not specified, all MLD group entries are
               cleared.";
          }
          leaf source {
            type inet:ipv6-address;
            description
              "Multicast source IPv6 address.
               If it is not specified, all MLD source-group entries are
               cleared.";
          }
        }
      } // rpc clear-mld-groups



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      /*
       * Notifications
       */
    }
    <CODE ENDS>

5. Security Considerations

   The data model defined does not introduce any security implications.
   This document does not change any underlying security issues
   inherent in [RFC8022].

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

   Registrant Contact: The IESG.

   XML: N/A, the requested URI is an XML namespace.

   --------------------------------------------------------------------

   This document registers the following YANG modules in the YANG Module
   Names registry [RFC7950]:

   --------------------------------------------------------------------

   name:         ietf-igmp-mld

   namespace:    urn:ietf:params:xml:ns:yang:ietf-igmp-mld

   prefix:       igmp-mld

   reference:    RFC XXXX

   --------------------------------------------------------------------





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7. Acknowledgments

    The authors would like to thank Steve Baillargeon, Hu Fangwei,
    Robert Kebler, Tanmoy Kundu, and Stig Venaas for their valuable
    contributions.

8. Contributing Authors

   Yisong Liu
   Huawei Technologies
   Huawei Bld., No.156 Beiqing Rd.
   Beijing  100095
   China

   Email: liuyisong@huawei.com


9. References

9.1. Normative References

   [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119, March 1997.

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

   [RFC6087] Bierman, A., "Guidelines for Authors and Reviewers of YANG
             Data Model Documents", RFC 6087, January 2011

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

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

   [RFC8022] Lhotka, L. and A. Lindem, "A YANG Data Model for Routing
             Management", RFC 8022, November 2016

   [I-D.dsdt-nmda-guidelines] M. Bjorklund, J. Schoenwaelder, P.
             Shafer, K. Watsen, R. Wilton, "Guidelines for YANG Module
             Authors (NMDA)", draft-dsdt-nmda-guidelines-01, May 2017

   [draft-bjorklund-netmod-rfc7223bis-00] M. Bjorklund, "A YANG Data
             Model for Interface Management",  draft-bjorklund-netmod-
             rfc7223bis-00, August 2017



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   [draft-bjorklund-netmod-rfc7277bis-00] M. Bjorklund, "A YANG Data
             Model for IP Management", draft-bjorklund-netmod-
             rfc7277bis-00, August 2017

   [I-D.ietf-netmod-rfc6087bis] Bierman, A., "Guidelines for Authors
             and Reviewers of YANG Data Model Documents", draft-ietf-
             netmod-rfc6087bis-14, September 2017

   [I-D.acee-netmod-rfc8022bis] L. Lhotka, A. Lindem and Y.Qu, "A YANG
             Data Model for Routing Management (NDMA Version)", draft-
             acee-netmod-rfc8022bis-02, September 2017

9.2. Informative References

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

   [RFC2236] Fenner, W., "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.

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

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

   [RFC4605] B. Fenner, H. He, B. Haberman, and H. Sandick, "Internet
             Group Management Protocol (IGMP) / Multicast Listener
             Discovery (MLD)-Based Multicast Forwarding ("IGMP/MLD
             Proxying")", RFC 4605, August 2006.

   [RFC5790] H. Liu, W. Cao and H. Asaeda, "Lightweight Internet Group
             Management Protocol Version 3 (IGMPv3) and Multicast
             Listener Discovery Version 2 (MLDv2) Protocols", RFC 5790,
             February 2010






Liu & Guo, etc           Expires April, 2018                 [Page 34]


Internet-Draft          IGMP & MLD Yang Model             October 2017


   Authors' Addresses

   Xufeng Liu
   Jabil
   8281 Greensboro Drive, Suite 200
   McLean VA 22102
   USA

   EMail: Xufeng_Liu@jabil.com


   Feng Guo
   Huawei
   Huawei Bld., No.156 Beiqing Rd.
   Beijing  100095
   China

   Email: guofeng@huawei.com


   Mahesh Sivakumar
   Cisco Systems, Inc.
   510 McCarthy Boulevard
   Milpitas, California 95035
   USA

   Email: masivaku@cisco.com


   Pete McAllister
   Metaswitch Networks
   100 Church Street
   Enfield  EN2 6BQ
   UK

   EMail: pete.mcallister@metaswitch.com


   Anish Peter
   Individual




   EMail: anish.ietf@gmail.com






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