Network Working Group R. Hinden
Request for Comments: 2373 Nokia
Obsoletes: 1884 S. Deering
Category: Standards Track Cisco Systems
July 1998
IP Version 6 Addressing Architecture
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 (1998). All Rights Reserved.
Abstract
This specification defines the addressing architecture of the IP
Version 6 protocol [IPV6]. The document includes the IPv6 addressing
model, text representations of IPv6 addresses, definition of IPv6
unicast addresses, anycast addresses, and multicast addresses, and an
IPv6 node's required addresses.
Table of Contents
1. Introduction.................................................2
2. IPv6 Addressing..............................................2
2.1 Addressing Model.........................................3
2.2 Text Representation of Addresses.........................3
2.3 Text Representation of Address Prefixes..................5
2.4 Address Type Representation..............................6
2.5 Unicast Addresses........................................7
2.5.1 Interface Identifiers................................8
2.5.2 The Unspecified Address..............................9
2.5.3 The Loopback Address.................................9
2.5.4 IPv6 Addresses with Embedded IPv4 Addresses.........10
2.5.5 NSAP Addresses......................................10
2.5.6 IPX Addresses.......................................10
2.5.7 Aggregatable Global Unicast Addresses...............11
2.5.8 Local-use IPv6 Unicast Addresses....................11
2.6 Anycast Addresses.......................................12
2.6.1 Required Anycast Address............................13
2.7 Multicast Addresses.....................................14
Hinden & Deering Standards Track [Page 1]
RFC 2373 IPv6 Addressing Architecture July 1998
2.7.1 Pre-Defined Multicast Addresses.....................15
2.7.2 Assignment of New IPv6 Multicast Addresses..........17
2.8 A Node's Required Addresses.............................17
3. Security Considerations.....................................18
APPENDIX A: Creating EUI-64 based Interface Identifiers........19
APPENDIX B: ABNF Description of Text Representations...........22
APPENDIX C: CHANGES FROM RFC-1884..............................23
REFERENCES.....................................................24
AUTHORS' ADDRESSES.............................................25
FULL COPYRIGHT STATEMENT.......................................26
1.0 INTRODUCTION
This specification defines the addressing architecture of the IP
Version 6 protocol. It includes a detailed description of the
currently defined address formats for IPv6 [IPV6].
The authors would like to acknowledge the contributions of Paul
Francis, Scott Bradner, Jim Bound, Brian Carpenter, Matt Crawford,
Deborah Estrin, Roger Fajman, Bob Fink, Peter Ford, Bob Gilligan,
Dimitry Haskin, Tom Harsch, Christian Huitema, Tony Li, Greg
Minshall, Thomas Narten, Erik Nordmark, Yakov Rekhter, Bill Simpson,
and Sue Thomson.
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].
2.0 IPv6 ADDRESSING
IPv6 addresses are 128-bit identifiers for interfaces and sets of
interfaces. There are three types of addresses:
Unicast: An identifier for a single interface. A packet sent to
a unicast address is delivered to the interface
identified by that address.
Anycast: An identifier for a set of interfaces (typically
belonging to different nodes). A packet sent to an
anycast address is delivered to one of the interfaces
identified by that address (the "nearest" one, according
datatracker.ietf.org