Internet Protocol Version 6 (IPv6) Addressing Architecture
RFC 3513

• Status
• IESG evaluation record
• IESG writeups
• Email expansions
• History

• Versions
• 10

Network Working Group                                          R. Hinden
Request for Comments: 3513                                         Nokia
Obsoletes: 2373                                               S. Deering
Category: Standards Track                                  Cisco Systems
                                                              April 2003

       Internet Protocol Version 6 (IPv6) 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 (2003).  All Rights Reserved.

Abstract

   This specification defines the addressing architecture of the IP
   Version 6 (IPv6) protocol.  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.

Hinden & Deering            Standards Track                     [Page 1]
RFC 3513              IPv6 Addressing Architecture            April 2003

Table of Contents

   1. Introduction.................................................3
   2. IPv6 Addressing..............................................3
      2.1 Addressing Model.........................................4
      2.2 Text Representation of Addresses.........................4
      2.3 Text Representation of Address Prefixes..................5
      2.4 Address Type Identification..............................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 Global Unicast Addresses..........................10
          2.5.5 IPv6 Addresses with Embedded IPv4 Addresses.......10
          2.5.6 Local-use IPv6 Unicast Addresses..................11
      2.6 Anycast Addresses.......................................12
          2.6.1 Required Anycast Address..........................13
      2.7 Multicast Addresses.....................................13
          2.7.1 Pre-Defined Multicast Addresses...................15
      2.8 A Node's Required Addresses.............................17
   3. Security Considerations.....................................17
   4. IANA Considerations.........................................18
   5. References..................................................19
      5.1 Normative References....................................19
      5.2 Informative References..................................19
   APPENDIX A: Creating Modified EUI-64 format Interface IDs......21
   APPENDIX B: Changes from RFC-2373..............................24
   Authors' Addresses.............................................25
   Full Copyright Statement.......................................26

Hinden & Deering            Standards Track                     [Page 2]
RFC 3513              IPv6 Addressing Architecture            April 2003

1.  Introduction

   This specification defines the addressing architecture of the IP
   Version 6 (IPv6) protocol.  It includes the basic formats for the
   various types of IPv6 addresses (unicast, anycast, and multicast).

   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,
   Sue Thomson, Markku Savela, and Larry Masinter.

2. IPv6 Addressing

   IPv6 addresses are 128-bit identifiers for interfaces and sets of
   interfaces (where "interface" is as defined in section 2 of [IPV6]).
   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 to the routing
              protocols' measure of distance).

   Multicast: An identifier for a set of interfaces (typically belonging
              to different nodes).  A packet sent to a multicast address
              is delivered to all interfaces identified by that address.