RFC 2710 (rfc2710) - Page 1 of 22


Multicast Listener Discovery (MLD) for IPv6



Alternative Format: Original Text Document



Network Working Group                                        S. Deering
Request for Comments: 2710                                Cisco Systems
Category: Standards Track                                     W. Fenner
                                                          AT&T Research
                                                            B. Haberman
                                                                    IBM
                                                           October 1999


              Multicast Listener Discovery (MLD) for IPv6

Status of this Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (1999).  All Rights Reserved.

Abstract

   This document specifies the protocol used by an IPv6 router to
   discover the presence of multicast listeners (that is, nodes wishing
   to receive multicast packets) on its directly attached links, and to
   discover specifically which multicast addresses are of interest to
   those neighboring nodes.  This protocol is referred to as Multicast
   Listener Discovery or MLD.  MLD is derived from version 2 of IPv4's
   Internet Group Management Protocol, IGMPv2.  One important difference
   to note is that MLD uses ICMPv6 (IP Protocol 58) message types,
   rather than IGMP (IP Protocol 2) message types.

1.  Definitions

   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 [KEYWORDS].

2.  Introduction

   The purpose of Multicast Listener Discovery (MLD) is to enable each
   IPv6 router to discover the presence of multicast listeners (that is,
   nodes wishing to receive multicast packets) on its directly attached
   links, and to discover specifically which multicast addresses are of
   interest to those neighboring nodes.  This information is then



Deering, et al.             Standards Track