RFC 2462 (rfc2462) - Page 2 of 25
IPv6 Stateless Address Autoconfiguration
Alternative Format: Original Text Document
RFC 2462 IPv6 Stateless Address Autoconfiguration December 1998
5.4. Duplicate Address Detection......................... 13
5.4.1. Message Validation............................. 14
5.4.2. Sending Neighbor Solicitation Messages......... 14
5.4.3. Receiving Neighbor Solicitation Messages....... 15
5.4.4. Receiving Neighbor Advertisement Messages...... 16
5.4.5. When Duplicate Address Detection Fails......... 16
5.5. Creation of Global and Site-Local Addresses......... 16
5.5.1. Soliciting Router Advertisements............... 16
5.5.2. Absence of Router Advertisements............... 17
5.5.3. Router Advertisement Processing................ 17
5.5.4. Address Lifetime Expiry........................ 19
5.6. Configuration Consistency........................... 19
6. SECURITY CONSIDERATIONS.................................. 20
7. References............................................... 20
8. Acknowledgements and Authors' Addresses.................. 21
9. APPENDIX A: LOOPBACK SUPPRESSION & DUPLICATE ADDRESS
DETECTION.............................................. 22
10. APPENDIX B: CHANGES SINCE RFC 1971....................... 24
11. Full Copyright Statement................................. 25
1. INTRODUCTION
This document specifies the steps a host takes in deciding how to
autoconfigure its interfaces in IP version 6. The autoconfiguration
process includes creating a link-local address and verifying its
uniqueness on a link, determining what information should be
autoconfigured (addresses, other information, or both), and in the
case of addresses, whether they should be obtained through the
stateless mechanism, the stateful mechanism, or both. This document
defines the process for generating a link-local address, the process
for generating site-local and global addresses via stateless address
autoconfiguration, and the Duplicate Address Detection procedure. The
details of autoconfiguration using the stateful protocol are
specified elsewhere.
IPv6 defines both a stateful and stateless address autoconfiguration
mechanism. Stateless autoconfiguration requires no manual
configuration of hosts, minimal (if any) configuration of routers,
and no additional servers. The stateless mechanism allows a host to
generate its own addresses using a combination of locally available
information and information advertised by routers. Routers advertise
prefixes that identify the subnet(s) associated with a link, while
hosts generate an "interface identifier" that uniquely identifies an
interface on a subnet. An address is formed by combining the two. In
the absence of routers, a host can only generate link-local
addresses. However, link-local addresses are sufficient for allowing
communication among nodes attached to the same link.
Thomson & Narten Standards Track