Internet Engineering Task Force (IETF) H. Zhao Request for Comments: 9166 Ericsson Category: Standards Track X. Liu ISSN: 2070-1721 IBM Corporation Y. Liu China Mobile A. Peter Individual M. Sivakumar Juniper Networks January 2022 A YANG Data Model for Internet Group Management Protocol (IGMP) and Multicast Listener Discovery (MLD) Snooping 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 the Network Management Datastore Architecture (NMDA). Status of This Memo This is an Internet Standards Track document. This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 7841. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at https://www.rfc-editor.org/info/rfc9166. Copyright Notice Copyright (c) 2022 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License. Table of Contents 1. Introduction 1.1. Terminology 1.2. Tree Diagrams 1.3. Prefixes in Data Node Names 2. Design of Data Model 2.1. Overview 2.2. Optional Capabilities 2.3. Position of Address Family in Hierarchy 3. Module Structure 3.1. IGMP Snooping Instances 3.2. MLD Snooping Instances 3.3. Using IGMP and MLD Snooping Instances 3.4. IGMP and MLD Snooping Actions 4. IGMP and MLD Snooping YANG Module 5. Security Considerations 6. IANA Considerations 6.1. XML Registry 6.2. YANG Module Names Registry 7. References 7.1. Normative References 7.2. Informative References Appendix A. Data Tree Example Authors' Addresses 1. Introduction This document defines a YANG [RFC7950] data model for the management of IGMP and MLD snooping [RFC4541] devices. The YANG module in this document conforms to the NMDA defined in [RFC8342]. The 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 is a router that has 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]. 1.2. Tree Diagrams Tree diagrams used in this document follow the notation defined in [RFC8340]. 1.3. Prefixes in Data Node Names In this document, names of data nodes, 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] | +----------+----------------------+-----------+ | 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 wasting bandwidth. 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 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 IGMP and 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 YANG module on IGMP and MLD snooping defined in this document has all the common building blocks for the IGMP and MLD snooping switches. The YANG module includes an IGMP and MLD snooping instance definition that uses the instance in the L2 service type of bridge [dot1Qcp]. It also includes actions for clearing IGMP and MLD snooping group tables. The YANG module doesn't cover L2VPN, which will be specified in a separate document. 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 to ensure 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. 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 intrinsic support for a piece of operational state would be able to derive a suitable value for a state variable that is not intrinsically 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. * Having separate branches for IGMP snooping and MLD snooping allows minor differences in their behavior to be modeled more simply and cleanly. The two branches can better support different features and node types. 3. Module Structure This model augments the core routing data model specified in [RFC8349]. +--rw routing +--rw router-id? +--rw control-plane-protocols | +--rw control-plane-protocol* [type name] | +--rw type | +--rw name | +--rw igmp-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. The YANG data model defined in this document conforms to the NMDA [RFC8342]. The operational state data is combined with the associated configuration data in the same hierarchy [RFC8407]. 3.1. IGMP Snooping Instances The YANG module ietf-igmp-mld-snooping augments /rt:routing/ rt:control-plane-protocols/rt:control-plane-protocol to add the igmp- snooping-instance container. All the IGMP snooping-related attributes have been defined in the igmp-snooping-instance. The read-write attributes represent configurable data. The read-only attributes represent state data. One igmp-snooping-instance could be used in one bridge [dot1Qcp] instance, and it corresponds to one bridge instance. Currently, the value of l2-service-type in igmp-snooping-instance could only be set to 'bridge'. After it is set, igmp-snooping- instance could be used in the bridge service. The values of bridge-mrouter-interface are filled by the snooping device dynamically. It is different from static-bridge-mrouter- interface, which is configured. 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 {igmp-snooping}? +--rw l2-service-type? l2-service-type +--rw enabled? boolean +--rw forwarding-table-type? enumeration +--rw explicit-tracking? boolean | {explicit-tracking}? +--rw lite-exclude-filter? empty | {lite-exclude-filter}? +--rw send-query? boolean +--rw fast-leave? empty {fast-leave}? +--rw last-member-query-interval? uint16 +--rw query-interval? uint16 +--rw query-max-response-time? uint16 +--rw require-router-alert? boolean | {require-router-alert}? +--rw robustness-variable? uint8 +--rw static-bridge-mrouter-interface* if:interface-ref | {static-mrouter-interface}? +--rw igmp-version? uint8 +--rw querier-source? inet:ipv4-address +--rw static-l2-multicast-group* [group source-addr] | {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 +--ro entries-count? yang:gauge32 +--ro bridge-mrouter-interface* if:interface-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 up-time uint32 | +--ro expire? | | rt-types:timer-value-seconds16 | +--ro host-count? yang:gauge32 | | {explicit-tracking}? | +--ro last-reporter? inet:ipv4-address | +--ro host* [address] {explicit-tracking}? | +--ro address inet:ipv4-address | +--ro filter-mode filter-mode-type +--ro interfaces +--ro interface* [name] +--ro name if:interface-ref +--ro statistics +--ro discontinuity-time? yang:date-and-time +--ro received | +--ro query-count? yang:counter64 | +--ro membership-report-v1-count? yang:counter64 | +--ro membership-report-v2-count? yang:counter64 | +--ro membership-report-v3-count? yang:counter64 | +--ro leave-count? yang:counter64 | +--ro pim-hello-count? yang:counter64 +--ro sent +--ro query-count? yang:counter64 +--ro membership-report-v1-count? yang:counter64 +--ro membership-report-v2-count? yang:counter64 +--ro membership-report-v3-count? yang:counter64 +--ro leave-count? yang:counter64 +--ro pim-hello-count? yang:counter64 3.2. MLD Snooping Instances The YANG module ietf-igmp-mld-snooping augments /rt:routing/ rt:control-plane-protocols/rt:control-plane-protocol to add the mld- snooping-instance container. The mld-snooping-instance could be used in the bridge [dot1Qcp] service to enable MLD snooping. All the MLD snooping-related attributes have been defined in the mld- snooping-instance. The read-write attributes represent configurable data. The read-only attributes represent state data. The mld-snooping-instance has a similar structure to IGMP snooping. Some leaves are protocol related. The mld-snooping-instance uses IPv6 addresses and mld-version, while igmp-snooping-instance uses IPv4 addresses and igmp-version. Statistic counters in each of the above snooping instances are also tailored to the specific protocol type. One mld-snooping-instance could be used in one bridge instance and corresponds to one bridge instance. Currently, the value of l2-service-type in mld-snooping-instance could only be set to 'bridge'. After it is set, mld-snooping- instance could be used in the bridge service. The value of bridge-mrouter-interface is filled by the snooping device dynamically. It is different from static-bridge-mrouter- interface, which is configured. 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 mld-snooping-instance {mld-snooping}? +--rw l2-service-type? l2-service-type +--rw enabled? boolean +--rw forwarding-table-type? enumeration +--rw explicit-tracking? boolean | {explicit-tracking}? +--rw lite-exclude-filter? empty | {lite-exclude-filter}? +--rw send-query? boolean +--rw fast-leave? empty {fast-leave}? +--rw last-member-query-interval? uint16 +--rw query-interval? uint16 +--rw query-max-response-time? uint16 +--rw require-router-alert? boolean | {require-router-alert}? +--rw robustness-variable? uint8 +--rw static-bridge-mrouter-interface* if:interface-ref | {static-mrouter-interface}? +--rw mld-version? uint8 +--rw querier-source? inet:ipv6-address +--rw static-l2-multicast-group* [group source-addr] | {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 +--ro entries-count? yang:gauge32 +--ro bridge-mrouter-interface* if:interface-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 up-time uint32 | +--ro expire? | | rt-types:timer-value-seconds16 | +--ro host-count? yang:gauge32 | | {explicit-tracking}? | +--ro last-reporter? inet:ipv6-address | +--ro host* [address] {explicit-tracking}? | +--ro address inet:ipv6-address | +--ro filter-mode filter-mode-type +--ro interfaces +--ro interface* [name] +--ro name if:interface-ref +--ro statistics +--ro discontinuity-time? yang:date-and-time +--ro received | +--ro query-count? yang:counter64 | +--ro report-v1-count? yang:counter64 | +--ro report-v2-count? yang:counter64 | +--ro done-count? yang:counter64 | +--ro pim-hello-count? yang:counter64 +--ro sent +--ro query-count? yang:counter64 +--ro report-v1-count? yang:counter64 +--ro report-v2-count? yang:counter64 +--ro done-count? yang:counter64 +--ro pim-hello-count? yang:counter64 3.3. Using IGMP and MLD Snooping Instances The igmp-snooping-instance could be used in the service of bridge [dot1Qcp] to configure the IGMP snooping. For the bridge service, this model augments /dot1q:bridges/ dot1q:bridge to use igmp-snooping-instance. It means IGMP snooping is enabled in the 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. The mld-snooping-instance could be used in concurrence with igmp- snooping-instance to configure the MLD snooping. 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 3.4. IGMP and MLD Snooping Actions IGMP and MLD snooping actions clear the specified IGMP and MLD snooping group tables. If both source X and group Y are specified, only source X from group Y in that specific instance will be cleared. augment /rt:routing/rt:control-plane-protocols /rt:control-plane-protocol: +--rw igmp-snooping-instance {igmp-snooping}? +---x clear-igmp-snooping-groups {action-clear-groups}? +---w input +---w group union +---w source rt-types:ipv4-multicast-source-address augment /rt:routing/rt:control-plane-protocols /rt:control-plane-protocol: +--rw mld-snooping-instance {mld-snooping}? +---x clear-mld-snooping-groups {action-clear-groups}? +---w input +---w group union +---w source rt-types:ipv6-multicast-source-address 4. IGMP and MLD Snooping YANG Module This module references [RFC1112], [RFC2236], [RFC2710], [RFC3376], [RFC3810], [RFC4541], [RFC5790], [RFC6636], [RFC6991], [RFC7761], [RFC8343], and [dot1Qcp]. file "ietf-igmp-mld-snooping@2022-01-31.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; 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 ieee802-dot1q-bridge { prefix dot1q; reference "dot1Qcp: IEEE 802.1Qcp-2018 Standard for Local and Metropolitan area networks--Bridges and Bridged Networks --Amendment 30: YANG Data Model"; } organization "IETF PIM Working Group"; contact "WG Web: WG List: Editors: Hongji Zhao Xufeng Liu Yisong Liu Anish Peter Mahesh Sivakumar "; 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, which is described in RFC 4541. Copyright (c) 2022 IETF Trust and the persons identified as authors of the code. All rights reserved. Redistribution and use in source and binary forms, with or without modification, is permitted pursuant to, and subject to the license terms contained in, the Revised BSD License set forth in Section 4.c of the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info). This version of this YANG module is part of RFC 9166; see the RFC itself for full legal notices."; revision 2022-01-31 { description "Initial revision."; reference "RFC 9166: A YANG Data Model for Internet Group Management Protocol (IGMP) and Multicast Listener Discovery (MLD) Snooping"; } /* * Features */ feature igmp-snooping { description "Support IGMP snooping."; reference "RFC 4541: Considerations for Internet Group Management Protocol (IGMP) and Multicast Listener Discovery (MLD) Snooping Switches"; } feature mld-snooping { description "Support MLD snooping."; reference "RFC 4541: Considerations for Internet Group Management Protocol (IGMP) and Multicast Listener Discovery (MLD) Snooping Switches"; } feature fast-leave { description "Support configuration of fast leave. The fast leave feature does not send last member query messages to hosts."; reference "RFC 3376: Internet Group Management Protocol, Version 3"; } feature static-l2-multicast-group { description "Support configuration of static L2 multicast group."; } feature static-mrouter-interface { description "Support multicast router interface explicitly configured by management."; reference "RFC 4541: Considerations for Internet Group Management Protocol (IGMP) and Multicast Listener Discovery (MLD) Snooping Switches"; } feature action-clear-groups { description "Support clearing statistics by action for IGMP and MLD snooping."; } feature require-router-alert { description "Support configuration of require-router-alert."; reference "RFC 3376: Internet Group Management Protocol, Version 3"; } feature lite-exclude-filter { description "Enable the support of the simplified EXCLUDE filter."; reference "RFC 5790: Lightweight Internet Group Management Protocol Version 3 (IGMPv3) and Multicast Listener Discovery Version 2 (MLDv2) Protocols"; } feature explicit-tracking { description "Support configuration of per-instance explicit-tracking."; reference "RFC 6636: Tuning the Behavior of the Internet Group Management Protocol (IGMP) and Multicast Listener Discovery (MLD) for Routers in Mobile and Wireless Networks"; } /* identities */ identity l2-service-type { description "Base identity for L2 service type in IGMP and MLD snooping."; } identity bridge { base l2-service-type; description "This identity represents bridge service."; } identity filter-mode { description "Base identity for filter mode in IGMP and 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 l2-service-type { type identityref { base l2-service-type; } description "The L2 service type used with IGMP and MLD snooping."; } 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 that need to reference IGMP or MLD snooping instance."; } /* * Groupings */ grouping instance-config-attributes-igmp-mld-snooping { description "IGMP and MLD snooping configuration of each VLAN."; leaf enabled { type boolean; default "false"; description "Set the value to true to enable IGMP and MLD snooping."; } leaf forwarding-table-type { type enumeration { enum mac { 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 "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 lite-exclude-filter { if-feature "lite-exclude-filter"; type empty; description "For IGMP snooping, the presence of this leaf enables the support of the simplified EXCLUDE filter in the Lightweight IGMPv3 protocol, which simplifies the standard versions of IGMPv3. For MLD Snooping, the presence of this leaf enables the support of the simplified EXCLUDE filter in the Lightweight MLDv2 protocol, which simplifies the standard versions of MLDv2."; reference "RFC 5790: Lightweight Internet Group Management Protocol Version 3 (IGMPv3) and Multicast Listener Discovery Version 2 (MLDv2) Protocols"; } leaf send-query { type boolean; default "false"; description "When it is true, this switch will send out a periodic IGMP General Query Message or MLD General Query Message."; } leaf fast-leave { if-feature "fast-leave"; type empty; description "When fast leave is enabled, the software assumes that no more than one host is present on each VLAN port."; } leaf last-member-query-interval { type uint16 { range "10..10230"; } units "deciseconds"; 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: Internet Group Management Protocol, Version 3, Section 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: Internet Group Management Protocol, Version 3, Sections 4.1.7, 8.2, and 8.14.2"; } leaf query-max-response-time { type uint16; units "deciseconds"; 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: Internet Group Management Protocol, Version 3, Sections 4.1.1, 8.3, and 8.14.3"; } leaf require-router-alert { if-feature "require-router-alert"; type boolean; default "false"; description "When the value is true, a router alert should exist in the IP header of the IGMP or MLD packet. If it doesn't exist, the IGMP or MLD packet will be ignored."; reference "RFC 3376: Internet Group Management Protocol, Version 3, Sections 9.1, 9.2, and 9.3"; } 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: Internet Group Management Protocol, Version 3, Sections 4.1.6, 8.1, and 8.14.1"; } leaf-list static-bridge-mrouter-interface { when 'derived-from-or-self(../l2-service-type,"ims:bridge")'; if-feature "static-mrouter-interface"; type if:interface-ref; description "Static mrouter interface in bridge forwarding"; } } // instance-config-attributes-igmp-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; description "The time elapsed since the L2 multicast record was created."; } } // instance-state-group-attributes-igmp-mld-snooping grouping instance-state-attributes-igmp-mld-snooping { description "State attributes for IGMP or MLD snooping instance."; leaf entries-count { type yang:gauge32; config false; description "The number of L2 multicast entries in IGMP and MLD snooping."; } leaf-list bridge-mrouter-interface { when 'derived-from-or-self(../l2-service-type,"ims:bridge")'; type if:interface-ref; config false; description "Indicates a list of mrouter interfaces dynamically learned in a bridge. When this switch receives IGMP/MLD queries from a multicast router on an interface, the interface will become an mrouter interface for IGMP/MLD snooping."; } } // instance-config-attributes-igmp-mld-snooping grouping instance-state-source-attributes-igmp-mld-snooping { description "State attributes for IGMP or MLD snooping instance."; leaf-list bridge-outgoing-interface { when 'derived-from-or-self(../../../l2-service-type, "ims:bridge")'; type if:interface-ref; description "Outgoing interface in bridge forwarding."; } leaf up-time { type uint32; units "seconds"; mandatory true; description "The time elapsed since L2 multicast record was created."; } leaf expire { type rt-types:timer-value-seconds16; units "seconds"; description "The time left before multicast group timeout."; } leaf host-count { if-feature "explicit-tracking"; type yang:gauge32; 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 query-count { type yang:counter64; description "The number of Membership Query messages."; reference "RFC 2236: Internet Group Management Protocol, Version 2"; } leaf membership-report-v1-count { type yang:counter64; description "The number of Version 1 Membership Report messages."; reference "RFC 1112: Host extensions for IP multicasting"; } leaf membership-report-v2-count { type yang:counter64; description "The number of Version 2 Membership Report messages."; reference "RFC 2236: Internet Group Management Protocol, Version 2"; } leaf membership-report-v3-count { type yang:counter64; description "The number of Version 3 Membership Report messages."; reference "RFC 3376: Internet Group Management Protocol, Version 3"; } leaf leave-count { type yang:counter64; description "The number of Leave Group messages."; reference "RFC 2236: Internet Group Management Protocol, Version 2"; } leaf pim-hello-count { type yang:counter64; description "The number of PIM hello messages."; reference "RFC 7761: Protocol Independent Multicast - Sparse Mode (PIM-SM): Protocol Specification (Revised)"; } } // igmp-snooping-statistics grouping mld-snooping-statistics { description "The statistics attributes for MLD snooping."; leaf query-count { type yang:counter64; description "The number of Multicast Listener Query messages."; reference "RFC 3810: Multicast Listener Discovery Version 2 (MLDv2) for IPv6"; } leaf report-v1-count { type yang:counter64; description "The number of Version 1 Multicast Listener Report."; reference "RFC 2710: Multicast Listener Discovery (MLD) for IPv6"; } leaf report-v2-count { type yang:counter64; description "The number of Version 2 Multicast Listener Report."; reference "RFC 3810: Multicast Listener Discovery Version 2 (MLDv2) for IPv6"; } leaf done-count { type yang:counter64; description "The number of Version 1 Multicast Listener Done."; reference "RFC 2710: Multicast Listener Discovery (MLD) for IPv6"; } leaf pim-hello-count { type yang:counter64; description "The number of PIM hello messages."; reference "RFC 7761: Protocol Independent Multicast - Sparse Mode (PIM-SM): Protocol Specification (Revised)"; } } // mld-snooping-statistics augment "/rt:routing/rt:control-plane-protocols" + "/rt:control-plane-protocol" { when 'derived-from-or-self(rt:type, "ims:igmp-snooping")' { description "This container is only valid for IGMP snooping."; } description "IGMP snooping augmentation to control-plane protocol configuration and state."; container igmp-snooping-instance { if-feature "igmp-snooping"; description "IGMP snooping instance to configure igmp-snooping."; leaf l2-service-type { type l2-service-type; default "bridge"; description "It indicates bridge or other services."; } 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 "The source address of the IGMP General Query message, which is sent out by this switch."; } list static-l2-multicast-group { if-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(../../l2-service-type, "ims:bridge")'; type if:interface-ref; description "Outgoing interface in bridge forwarding."; } } // static-l2-multicast-group 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 that has sent a 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 that has sent a report to join the multicast group."; } list host { if-feature "explicit-tracking"; key "address"; description "List of multicast membership hosts of the specific multicast source group."; leaf address { type inet:ipv4-address; description "Multicast membership host address."; } leaf 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 container interfaces { config false; description "Contains the interfaces associated with the IGMP snooping instance."; list interface { key "name"; description "A list of interfaces associated with the IGMP snooping instance."; leaf name { type if:interface-ref; description "The name of the interface."; } container statistics { description "The interface statistics for IGMP snooping."; 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."; } container received { description "Number of received snooped IGMP packets."; uses igmp-snooping-statistics; } container sent { description "Number of sent snooped IGMP packets."; uses igmp-snooping-statistics; } } } } action clear-igmp-snooping-groups { if-feature "action-clear-groups"; description "Clear IGMP snooping cache tables."; input { leaf group { type union { type enumeration { enum all-groups { description "All multicast group addresses."; } } type rt-types:ipv4-multicast-group-address; } mandatory true; description "Multicast group IPv4 address. If value 'all-groups' is specified, all IGMP snooping group entries are cleared for the specified source address."; } leaf source { type rt-types:ipv4-multicast-source-address; mandatory true; description "Multicast source IPv4 address. If value '*' is specified, all IGMP snooping source-group tables are cleared."; } } } // action clear-igmp-snooping-groups } // igmp-snooping-instance } // augment augment "/rt:routing/rt:control-plane-protocols" + "/rt:control-plane-protocol" { when 'derived-from-or-self(rt:type, "ims:mld-snooping")' { description "This container is only valid for MLD snooping."; } description "MLD snooping augmentation to control-plane protocol configuration and state."; container mld-snooping-instance { if-feature "mld-snooping"; description "MLD snooping instance to configure mld-snooping."; leaf l2-service-type { type l2-service-type; default "bridge"; description "It indicates bridge or other services."; } 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 "The source address of MLD General Query message, which is sent out by this switch."; } list static-l2-multicast-group { if-feature "static-l2-multicast-group"; key "group source-addr"; description "A static multicast route, (*,G) or (S,G)."; leaf group { 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(../../l2-service-type, "ims:bridge")'; type if:interface-ref; description "Outgoing interface in bridge forwarding."; } } // static-l2-multicast-group 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 that 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 "Address of the last host that has sent report to join the multicast group."; } list host { if-feature "explicit-tracking"; key "address"; description "List of multicast membership hosts of the specific multicast source group."; leaf address { type inet:ipv6-address; description "Multicast membership host address."; } leaf 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 container interfaces { config false; description "Contains the interfaces associated with the MLD snooping instance."; list interface { key "name"; description "A list of interfaces associated with the MLD snooping instance."; leaf name { type if:interface-ref; description "The name of the interface."; } container statistics { description "The interface statistics for MLD snooping."; 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."; } container received { description "Number of received snooped MLD packets."; uses mld-snooping-statistics; } container sent { description "Number of sent snooped MLD packets."; uses mld-snooping-statistics; } } } } action clear-mld-snooping-groups { if-feature "action-clear-groups"; description "Clear MLD snooping cache tables."; input { leaf group { type union { type enumeration { enum all-groups { description "All multicast group addresses."; } } type rt-types:ipv6-multicast-group-address; } mandatory true; description "Multicast group IPv6 address. If value 'all-groups' is specified, all MLD snooping group entries are cleared for the specified source address."; } leaf source { type rt-types:ipv6-multicast-source-address; mandatory true; description "Multicast source IPv6 address. If value '*' is specified, all MLD snooping source-group tables are cleared."; } } } // action clear-mld-snooping-groups } // mld-snooping-instance } // augment augment "/dot1q:bridges/dot1q:bridge" { description "Use IGMP or MLD snooping instance in bridge."; leaf igmp-snooping-instance { type igmp-mld-snooping-instance-ref; description "Configure IGMP snooping instance under bridge view."; } leaf mld-snooping-instance { 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 or MLD snooping instance in a 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."; } } } 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 Unauthorized access to any data node of these subtrees can adversely affect the IGMP and 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 and MLD snooping on this device. The group/source/host information may expose multicast group memberships and, transitively, the associations between the user on the host and the contents from the source, which could be privately sensitive. Some of the action 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: Under /rt:routing/rt:control-plane-protocols/rt:control-plane- protocol:/ ims:igmp-snooping-instance/ims:clear-igmp-snooping-groups ims:mld-snooping-instance/ims:clear-mld-snooping-groups Some of the actions in this YANG module may be considered sensitive or vulnerable in some network environments. The IGMP and MLD snooping YANG module supports the "clear-igmp-snooping-groups" and "clear-mld-snooping-groups" actions. If unauthorized action is invoked, the IGMP and MLD snooping group tables will be cleared unexpectedly. Especially when using wildcard, all the multicast traffic will be flooded in the broadcast domain. The devices that use this YANG module should heed the security considerations in [RFC4541]. 6. IANA Considerations 6.1. XML Registry This document registers the following namespace URI 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. 6.2. YANG Module Names Registry This document registers the following YANG module 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 9166 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, DOI 10.1109/IEEESTD.2018.8467507, September 2018, . [RFC1112] Deering, S., "Host extensions for IP multicasting", STD 5, RFC 1112, DOI 10.17487/RFC1112, August 1989, . [RFC2236] Fenner, W., "Internet Group Management Protocol, Version 2", RFC 2236, DOI 10.17487/RFC2236, November 1997, . [RFC2710] Deering, S., Fenner, W., and B. Haberman, "Multicast Listener Discovery (MLD) for IPv6", RFC 2710, DOI 10.17487/RFC2710, October 1999, . [RFC3376] Cain, B., Deering, S., Kouvelas, I., Fenner, B., and A. Thyagarajan, "Internet Group Management Protocol, Version 3", RFC 3376, DOI 10.17487/RFC3376, October 2002, . [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, January 2004, . [RFC3810] Vida, R., Ed. and L. Costa, Ed., "Multicast Listener Discovery Version 2 (MLDv2) for IPv6", RFC 3810, DOI 10.17487/RFC3810, June 2004, . [RFC4286] Haberman, B. and J. Martin, "Multicast Router Discovery", RFC 4286, DOI 10.17487/RFC4286, December 2005, . [RFC4541] Christensen, M., Kimball, K., and F. Solensky, "Considerations for Internet Group Management Protocol (IGMP) and Multicast Listener Discovery (MLD) Snooping Switches", RFC 4541, DOI 10.17487/RFC4541, May 2006, . [RFC5790] Liu, H., Cao, W., and H. Asaeda, "Lightweight Internet Group Management Protocol Version 3 (IGMPv3) and Multicast Listener Discovery Version 2 (MLDv2) Protocols", RFC 5790, DOI 10.17487/RFC5790, February 2010, . [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010, . [RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., and A. Bierman, Ed., "Network Configuration Protocol (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011, . [RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011, . [RFC6636] Asaeda, H., Liu, H., and 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, DOI 10.17487/RFC6636, May 2012, . [RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types", RFC 6991, DOI 10.17487/RFC6991, July 2013, . [RFC7761] Fenner, B., Handley, M., Holbrook, H., Kouvelas, I., Parekh, R., Zhang, Z., and L. Zheng, "Protocol Independent Multicast - Sparse Mode (PIM-SM): Protocol Specification (Revised)", STD 83, RFC 7761, DOI 10.17487/RFC7761, March 2016, . [RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language", RFC 7950, DOI 10.17487/RFC7950, August 2016, . [RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017, . [RFC8294] Liu, X., Qu, Y., Lindem, A., Hopps, C., and L. Berger, "Common YANG Data Types for the Routing Area", RFC 8294, DOI 10.17487/RFC8294, December 2017, . [RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018, . [RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration Access Control Model", STD 91, RFC 8341, DOI 10.17487/RFC8341, March 2018, . [RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K., and R. Wilton, "Network Management Datastore Architecture (NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018, . [RFC8343] Bjorklund, M., "A YANG Data Model for Interface Management", RFC 8343, DOI 10.17487/RFC8343, March 2018, . [RFC8349] Lhotka, L., Lindem, A., and Y. Qu, "A YANG Data Model for Routing Management (NMDA Version)", RFC 8349, DOI 10.17487/RFC8349, March 2018, . [RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018, . 7.2. Informative References [RFC7951] Lhotka, L., "JSON Encoding of Data Modeled with YANG", RFC 7951, DOI 10.17487/RFC7951, August 2016, . [RFC8407] Bierman, A., "Guidelines for Authors and Reviewers of Documents Containing YANG Data Models", BCP 216, RFC 8407, DOI 10.17487/RFC8407, October 2018, . [RFC8652] Liu, X., Guo, F., Sivakumar, M., McAllister, P., and A. Peter, "A YANG Data Model for the Internet Group Management Protocol (IGMP) and Multicast Listener Discovery (MLD)", RFC 8652, DOI 10.17487/RFC8652, November 2019, . Appendix A. Data Tree Example This section contains an example of bridge service 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":{ "l2-service-type":"ietf-igmp-mld-snooping:bridge", "enabled":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", "name": "bis1", "ietf-igmp-mld-snooping:igmp-snooping-instance": { "l2-service-type": "ietf-igmp-mld-snooping:bridge", "enabled": 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 following action is to clear all the entries whose group address is 225.1.1.1 for igmp-snooping-instance bis1. POST /restconf/operations/ietf-routing:routing/\ control-plane-protocols/\ control-plane-protocol=ietf-igmp-mld-snooping:igmp-snooping,bis1/\ ietf-igmp-mld-snooping:igmp-snooping-instance/\ clear-igmp-snooping-groups HTTP/1.1 Host: example.com Content-Type: application/yang-data+json { "ietf-igmp-mld-snooping:input" : { "group": "225.1.1.1", "source": "*" } } Authors' Addresses Hongji Zhao Ericsson (China) Communications Company Ltd. Ericsson Tower, No. 5 Lize East Street Beijing 100102 China Email: hongji.zhao@ericsson.com Xufeng Liu IBM Corporation 2300 Dulles Station Blvd. Herndon, VA 20171 United States of America 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, CA United States of America Email: sivakumar.mahesh@gmail.com