RFC 3306 (rfc3306) - Page 2 of 7
Unicast-Prefix-based IPv6 Multicast Addresses
Alternative Format: Original Text Document
RFC 3306 Unicast-Prefix-based IPv6 Multicast August 2002
1. Introduction
This document specifies an extension to the multicast portion of the
IPv6 addressing architecture [ADDRARCH]. The current architecture
does not contain any built-in support for dynamic address allocation.
This proposal introduces encoded information in the multicast address
to allow for dynamic allocation of IPv6 multicast addresses and IPv6
source-specific multicast addresses.
2. Motivation
The current IPv4 multicast address allocation architecture [RFC 2908]
is based on a multi-layered, multi-protocol system. The goal of this
proposal is to reduce the number of protocols that need to be
deployed in order to get dynamic multicast address allocation.
The use of unicast prefix-based multicast address allocation will, at
a minimum, remove the need to run the Multicast Address Allocation
Protocol (AAP) [AAP WORK] and the Multicast Address-Set Claim (MASC)
Protocol [RFC 2909].
3. 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].
4. Multicast Address Format
Section 2.7 of [ADDRARCH] defines the following operational format of
IPv6 multicast addresses:
| 8 | 4 | 4 | 112 |
+--------+----+----+---------------------------------------------+
|11111111|flgs|scop| group ID |
+--------+----+----+---------------------------------------------+
Haberman & Thaler Standards Track