RFC 3307 (rfc3307) - Page 2 of 8

Allocation Guidelines for IPv6 Multicast Addresses

RFC 3307          IPv6 Multicast Addresses Guidelines        August 2002


Table of Contents

   1. Terminology.....................................................2
   2. Introduction....................................................2
   3. Applicability...................................................3
   4. Group ID Selection Guidelines...................................3
   4.1  Permanent IPv6 Multicast Addresses............................4
   4.2  Permanent IPv6 Multicast Group Identifiers....................4
   4.3  Dynamic IPv6 Multicast Addresses..............................4
   4.3.1 Server Allocation............................................5
   4.3.2 Host Allocation..............................................5
   5. IANA Considerations.............................................5
   6. Security Considerations.........................................6
   7. Acknowledgements................................................6
   8. References......................................................6
   Author's Address...................................................7
   Full Copyright Statement...........................................8

1. Terminology

   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].

   The term "group ID", throughout this document, conforms to the
   definition contained in [UNIMCAST], that is, the low-order 32 bits of
   the IPv6 multicast address.

2. Introduction

   This document specifies guidelines that MUST be implemented by any
   entity responsible for allocating IPv6 multicast addresses.  This
   includes, but is not limited to, any documents or entities wishing to
   assign permanent IPv6 multicast addresses, allocate dynamic IPv6
   multicast addresses, and define permanent IPv6 multicast group
   identifiers.  The purpose of these guidelines is to reduce the
   probability of IPv6 multicast address collision, not only at the IPv6
   layer, but also at the link-layer of media that encode portions of
   the IP layer address into the link-layer address.

   With the current IPv6 address architecture [ADDRARCH] and the
   extension to the multicast address architecture specified in
   [UNIMCAST], a set of guidelines is needed for entities assigning any
   flavor of IPv6 multicast addresses.

   The current approach of several physical media [RFC 2464][RFC 2467]
   is to map a portion of the IPv6 multicast address into a link-layer
   destination address.  This is accomplished by taking the low order 32



Haberman                    Standards Track