OSPF for IPv6
RFC 2740
Document | Type |
RFC - Proposed Standard
(December 1999; Errata)
Obsoleted by RFC 5340
|
|
---|---|---|---|
Authors | Rob Coltun , Dennis Ferguson , John Moy | ||
Last updated | 2020-01-21 | ||
Stream | IETF | ||
Formats | plain text html pdf htmlized with errata bibtex | ||
Stream | WG state | (None) | |
Document shepherd | No shepherd assigned | ||
IESG | IESG state | RFC 2740 (Proposed Standard) | |
Consensus Boilerplate | Unknown | ||
Telechat date | |||
Responsible AD | (None) | ||
Send notices to | (None) |
Network Working Group R. Coltun Requests for Comments: 2740 Siara Systems Category: Standards Track D. Ferguson Juniper Networks J. Moy Sycamore Networks December 1999 OSPF for IPv6 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 (1999). All Rights Reserved. Abstract This document describes the modifications to OSPF to support version 6 of the Internet Protocol (IPv6). The fundamental mechanisms of OSPF (flooding, DR election, area support, SPF calculations, etc.) remain unchanged. However, some changes have been necessary, either due to changes in protocol semantics between IPv4 and IPv6, or simply to handle the increased address size of IPv6. Changes between OSPF for IPv4 and this document include the following. Addressing semantics have been removed from OSPF packets and the basic LSAs. New LSAs have been created to carry IPv6 addresses and prefixes. OSPF now runs on a per-link basis, instead of on a per-IP-subnet basis. Flooding scope for LSAs has been generalized. Authentication has been removed from the OSPF protocol itself, instead relying on IPv6's Authentication Header and Encapsulating Security Payload. Most packets in OSPF for IPv6 are almost as compact as those in OSPF for IPv4, even with the larger IPv6 addresses. Most field-XSand packet-size limitations present in OSPF for IPv4 have been relaxed. In addition, option handling has been made more flexible. Coltun, et al. Standards Track [Page 1] RFC 2740 OSPF for IPv6 December 1999 All of OSPF for IPv4's optional capabilities, including on-demand circuit support, NSSA areas, and the multicast extensions to OSPF (MOSPF) are also supported in OSPF for IPv6. Table of Contents 1 Introduction ........................................... 4 1.1 Terminology ............................................ 4 2 Differences from OSPF for IPv4 ......................... 4 2.1 Protocol processing per-link, not per-subnet ........... 5 2.2 Removal of addressing semantics ........................ 5 2.3 Addition of Flooding scope ............................. 5 2.4 Explicit support for multiple instances per link ....... 6 2.5 Use of link-local addresses ............................ 6 2.6 Authentication changes ................................. 7 2.7 Packet format changes .................................. 7 2.8 LSA format changes ..................................... 8 2.9 Handling unknown LSA types ............................ 10 2.10 Stub area support ..................................... 10 2.11 Identifying neighbors by Router ID .................... 11 3 Implementation details ................................ 11 3.1 Protocol data structures .............................. 12 3.1.1 The Area Data structure ............................... 13 3.1.2 The Interface Data structure .......................... 13 3.1.3 The Neighbor Data Structure ........................... 14 3.2 Protocol Packet Processing ............................ 15 3.2.1 Sending protocol packets .............................. 15 3.2.1.1 Sending Hello packets ................................. 16 3.2.1.2 Sending Database Description Packets .................. 17 3.2.2 Receiving protocol packets ............................ 17 3.2.2.1 Receiving Hello Packets ............................... 19 3.3 The Routing table Structure ........................... 19 3.3.1 Routing table lookup .................................. 20 3.4 Link State Advertisements ............................. 20 3.4.1 The LSA Header ........................................ 21 3.4.2 The link-state database ............................... 22 3.4.3 Originating LSAs ...................................... 22 3.4.3.1 Router-LSAs ........................................... 25 3.4.3.2 Network-LSAs .......................................... 27 3.4.3.3 Inter-Area-Prefix-LSAs ................................ 28 3.4.3.4 Inter-Area-Router-LSAs ................................ 29Show full document text