PIM H. Zhao
Internet-Draft Ericsson
Intended status: Informational L. M. Contreras
Expires: 4 September 2025 Telefonica
X. Liu
Alef Edge
3 March 2025

Yang Data Model for supporting multipath IGMP/MLD proxies
draft-zcl-pim-multiif-igmp-mld-proxy-yang-00

Abstract

The ability to support multiple upstream interfaces in IGMP/MLD
proxies necessitates configuring different upstream interfaces for
specific multicast channels or sessions. [RFC9398] defined YANG Data
Model for Internet Group Management Protocol (IGMP) and Multicast
Listener Discovery (MLD) Proxy Devices. Building on that foundation,
this document proposes an augmentation of thet model for the support
of multiple upstream interfaces in IGMP/MLD proxies.

Status of This Memo

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

Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
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material or to cite them other than as "work in progress."

This Internet-Draft will expire on 4 September 2025.

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

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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 . . . . . . . . . . . . . . . . . . . . . . . . 2
2. IGMP/MLD proxy with multiple upstream interfaces . . . . . . 2
3. Data Model for supporting IGMP/MLD proxy with multiple upstream
interfaces . . . . . . . . . . . . . . . . . . . . . . . 3
3.1. YANG schema tree . . . . . . . . . . . . . . . . . . . . 3
3.2. IGMP Proxy YANG Module for supporting multiple upstream
interfaces . . . . . . . . . . . . . . . . . . . . . . . 3
3.3. MLD Proxy YANG Module for supporting multiple upstream
interfaces . . . . . . . . . . . . . . . . . . . . . . . 7
4. Security considerations . . . . . . . . . . . . . . . . . . . 7
5. Informative References . . . . . . . . . . . . . . . . . . . 7
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8

1. Introduction

An IGMP/MLD proxy with multiple upstream interfaces, as outlined in
[I-D.ietf-pim-multipath-igmpmldproxy], enables a device to receive
multicast sessions or channels through different upstream interfaces.
The selection of a specific upstream interface can be determined
based on various factors, including subscriber address prefixes,
channel or session IDs, and interface priority values.

[I-D.ietf-pim-multipath-igmpmldproxy] explores two approaches for the
automatic configuration of upstream interfaces. One approach
involves a centralized controller managing the configuration,
requiring the proxy to have a control and management interface to
receive instructions. Alternatively, configuration can be achieved
through a signaling-based mechanism using IGMP/MLD messages. While
the latter approach is addressed in
[I-D.contreras-pim-multiif-config], this document focuses on the
former approach, defining augmentations to the model defined in
[RFC9398].

2. IGMP/MLD proxy with multiple upstream interfaces

[I-D.ietf-pim-multipath-igmpmldproxy] defines the capabilities of an
IGMP/MLD proxy device in receiving multicast sessions or channels
through multiple upstream interfaces. The proxy can operate using
either "channel-based upstream selection," "subscriber-based upstream
selection," or a combination of both. In channel-based upstream
selection, the proxy selects one or more upstream interfaces from the

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available candidates for each specific channel or session. In
subscriber-based upstream selection, the proxy assigns one or more
upstream interfaces for each subscriber or receiver.

By supporting content subscription through multiple upstream
interfaces, the proxy can either distribute the load across sessions
and channels or receive content simultaneously from multiple upstream
interfaces. This enhances the reliability of content delivery.
Therefore, the enablement of scenarios where a channel is subscribed
to and received through more than one upstream interface
simultaneously are of interest.

3. Data Model for supporting IGMP/MLD proxy with multiple upstream
interfaces

The model presented in this document augments the fundamental
components required for IGMP/MLD proxy devices described in [RFC9398]
for allowing the configuration of multiple upstream interfaces in
those devices.

3.1. YANG schema tree

The YANG schema tree intended for enabling the support of multipath
for IGMP proxies is defined in the following way.

module: ietf-multipath-igmp-mld-proxy

augment /rt:routing/rt:control-plane-protocols/rt:control-plane-protocol/igmp-mld-proxy:igmp-proxy:
+--rw default-upstream-interface? -> ../igmp-mld-proxy:interfaces/interface/name {multipath-igmp-proxy}?
+--rw upstream-interface-takeover? boolean {multipath-igmp-proxy}?
augment /rt:routing/rt:control-plane-protocols/rt:control-plane-protocol/igmp-mld-proxy:igmp-proxy/igmp-mld-proxy:interfaces/igmp-mld-proxy:interface:
+--rw interface-priority? uint32 {multipath-igmp-proxy}?
+--rw active-interval? uint32 {multipath-igmp-proxy}?
+--rw subscriber* [address-prefix] {multipath-igmp-proxy}?
+--rw address-prefix inet:ipv4-address-no-zone
+--rw group* [address-prefix]
+--rw address-prefix rt-types:ipv4-multicast-group-address
+--rw source* [address-prefix]
+--rw address-prefix inet:ipv4-address-no-zone

The schema for MLD will be provided in later versions of this
document.

3.2. IGMP Proxy YANG Module for supporting multiple upstream interfaces

The model for IGMP is defined as follows:

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module ietf-multipath-igmp-mld-proxy {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-multipath-igmp-mld-proxy";
// replace with IANA namespace when assigned
prefix multipath-igmp-mld-proxy;

import ietf-inet-types {
prefix inet;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-routing {
prefix rt;
reference
"RFC 8349: A YANG Data Model for Routing Management (NMDA
Version)";
}
import ietf-routing-types {
prefix rt-types;
reference
"RFC 8294: Common YANG Data Types for the Routing Area";
}
import ietf-igmp-mld-proxy {
prefix igmp-mld-proxy;
reference
"RFC 9398: A YANG Data Model for IGMP/MLD Proxy";
}

organization
"IETF PIM Working Group";

contact
"WG Web: <https://datatracker.ietf.org/wg/pim/about/>
WG List: <mailto:pim@ietf.org>
";

description
"The module defines a collection of YANG definitions common for
Multipath IGMP/MLD Proxy devices.

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

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(http://trustee.ietf.org/license-info).

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

revision 2025-03-03 {
description
"Initial revision.";
reference
"RFC XXXX: A YANG Data Model for Multipath IGMP/MLD Proxy";
}

/*
* Features
*/

feature multipath-igmp-proxy {
description
"Multipath Support for IGMP Proxy.";
reference
"draft-ietf-pim-multipath-igmpmldproxy";
}

feature multipath-mld-proxy {
description
"Multipath Support for MLD Proxy.";
reference
"draft-ietf-pim-multipath-igmpmldproxy";
}

/* augments */

augment "/rt:routing/rt:control-plane-protocols"+
"/rt:control-plane-protocol/igmp-mld-proxy:igmp-proxy" {
description
"";
leaf default-upstream-interface {
if-feature "multipath-igmp-proxy";
type leafref {
path "../igmp-mld-proxy:interfaces/igmp-mld-proxy:interface/igmp-mld-proxy:name";
}
description
"It is used as the upstream interface when candidate
upstream interfaces are not configured for the subscriber
address prefix, channel/session ID, or interface priority value.";
}
leaf upstream-interface-takeover {

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if-feature "multipath-igmp-proxy";
type boolean;
default true;
description
"If a proxy device detects that a selected upstream interface
is going down or inactive, it disables the current upstream
interface and selects another active upstream interface with
the highest priority among the candidate upstream interfaces
covering the same channel/session ID.";
}
}

augment "/rt:routing/rt:control-plane-protocols"+
"/rt:control-plane-protocol/igmp-mld-proxy:igmp-proxy"+
"/igmp-mld-proxy:interfaces/igmp-mld-proxy:interface" {
description
"";

leaf interface-priority {
if-feature "multipath-igmp-proxy";
type uint32;
default 0;
description
"A lower value indicates a lower priority";
}

leaf active-interval {
if-feature "multipath-igmp-proxy";
type uint32;
description
"An active interval is a period in which the selected upstream
interface on the proxy device remains active.";
}

list subscriber {
if-feature "multipath-igmp-proxy";
key "address-prefix";
leaf address-prefix {
type inet:ipv4-address-no-zone;
description
"Subscriber-based upstream selection involves IGMP/MLD proxy devices
selecting one or multiple upstream interface(s) from candidate
upstream interfaces per subscriber/receiver.
When setting 0.0.0.0, it indicates any host";
}
list group {
key "address-prefix";
leaf address-prefix {

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type rt-types:ipv4-multicast-group-address;
description
"Channel/session ID consists of source address prefix
and multicast address prefix. This is multicast address prefix.
When setting 224.0.0.0, indicates the entire multicast address range";
}
list source {
key "address-prefix";
leaf address-prefix {
type inet:ipv4-address-no-zone;
description
"Channel/session ID consists of source address prefix
and multicast address prefix. This is source address prefix.
When setting 0.0.0.0, it indicates any host";
}
} // source
} // group
} // subscriber
}
}

3.3. MLD Proxy YANG Module for supporting multiple upstream interfaces

This model will be provided in a future version of this document.

4. Security considerations

Same security considerations as in both [RFC9398] and
[I-D.ietf-pim-multipath-igmpmldproxy] apply also to this document.

Further security considerations are under study.

5. Informative References

[I-D.contreras-pim-multiif-config]
Contreras, L. M. and H. Asaeda, "Signaling-based
configuration for supporting multiple upstream interfaces
in IGMP/MLD proxies", Work in Progress, Internet-Draft,
draft-contreras-pim-multiif-config-02, 21 October 2024,
<https://datatracker.ietf.org/doc/html/draft-contreras-
pim-multiif-config-02>.

[I-D.ietf-pim-multipath-igmpmldproxy]
Asaeda, H. and L. M. Contreras, "Multipath Support for
IGMP/MLD Proxy", Work in Progress, Internet-Draft, draft-
ietf-pim-multipath-igmpmldproxy-01, 21 October 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-pim-
multipath-igmpmldproxy-01>.

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[RFC9398] Zhao, H., Liu, X., Liu, Y., Panchanathan, M., and M.
Sivakumar, "A YANG Data Model for Internet Group
Management Protocol (IGMP) and Multicast Listener
Discovery (MLD) Proxy Devices", RFC 9398,
DOI 10.17487/RFC9398, May 2023,
<https://www.rfc-editor.org/info/rfc9398>.

Authors' Addresses

Hongji Zhao
Ericsson
Ericsson Tower, No. 5 Lize East Street, Chaoyang District
Beijing
100102
China
Email: hongji.zhao@ericsson.com

Luis M. Contreras
Telefonica
Ronda de la Comunicacion, s/n
28050 Madrid
Spain
Email: luismiguel.contrerasmurillo@telefonica.com
URI: http://lmcontreras.com

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

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