From 4bfd864f10b68b71482b35c818559068ef8d5797 Mon Sep 17 00:00:00 2001 From: Thomas Voss Date: Wed, 27 Nov 2024 20:54:24 +0100 Subject: doc: Add RFC documents --- doc/rfc/rfc6286.txt | 227 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 227 insertions(+) create mode 100644 doc/rfc/rfc6286.txt (limited to 'doc/rfc/rfc6286.txt') diff --git a/doc/rfc/rfc6286.txt b/doc/rfc/rfc6286.txt new file mode 100644 index 0000000..2fed690 --- /dev/null +++ b/doc/rfc/rfc6286.txt @@ -0,0 +1,227 @@ + + + + + + +Internet Engineering Task Force (IETF) E. Chen +Request for Comments: 6286 J. Yuan +Updates: 4271 Cisco Systems +Category: Standards Track June 2011 +ISSN: 2070-1721 + + + Autonomous-System-Wide Unique BGP Identifier for BGP-4 + +Abstract + + To accommodate situations where the current requirements for the BGP + Identifier are not met, this document relaxes the definition of the + BGP Identifier to be a 4-octet, unsigned, non-zero integer and + relaxes the "uniqueness" requirement so that only Autonomous-System- + wide (AS-wide) uniqueness of the BGP Identifiers is required. These + revisions to the base BGP specification do not introduce any backward + compatibility issues. This document updates RFC 4271. + +Status of This Memo + + This is an Internet Standards Track document. + + This document is a product of the Internet Engineering Task Force + (IETF). It represents the consensus of the IETF community. It has + received public review and has been approved for publication by the + Internet Engineering Steering Group (IESG). Further information on + Internet Standards is available in Section 2 of RFC 5741. + + Information about the current status of this document, any errata, + and how to provide feedback on it may be obtained at + http://www.rfc-editor.org/info/rfc6286. + +Copyright Notice + + Copyright (c) 2011 IETF Trust and the persons identified as the + document authors. All rights reserved. + + This document is subject to BCP 78 and the IETF Trust's Legal + Provisions Relating to IETF Documents + (http://trustee.ietf.org/license-info) in effect on the date of + publication of this document. Please review these documents + carefully, as they describe your rights and restrictions with respect + to this document. Code Components extracted from this document must + include Simplified BSD License text as described in Section 4.e of + the Trust Legal Provisions and are provided without warranty as + described in the Simplified BSD License. + + + + +Chen & Yuan Standards Track [Page 1] + +RFC 6286 AS-Wide Unique BGP ID for BGP-4 June 2011 + + +1. Introduction + + Currently, the BGP Identifier of a BGP speaker is specified as a + valid IPv4 host address assigned to the BGP speaker [RFC4271]. In + addition, the deployed BGP code requires that two BGP speakers be of + distinct BGP Identifiers in order to establish a BGP connection. + + To accommodate situations where the current requirements for the BGP + Identifier are not met (such as in the case of an IPv6-only network), + this document relaxes the definition of the BGP Identifier to be a + 4-octet, unsigned, non-zero integer and relaxes the "uniqueness" + requirement so that only AS-wide uniqueness of the BGP Identifiers is + required. These revisions to the base BGP specification do not + introduce any backward compatibility issues. + +2. Protocol Revisions + + The revisions to the base BGP specification [RFC4271] include the + definition of the BGP Identifier and procedures for a BGP speaker + that supports the AS-wide Unique BGP Identifier. + +2.1. Definition of the BGP Identifier + + For a BGP speaker that supports the AS-wide Unique BGP Identifier, + the BGP Identifier is specified as the following: + + The BGP Identifier is a 4-octet, unsigned, non-zero integer that + should be unique within an AS. The value of the BGP Identifier + for a BGP speaker is determined on startup and is the same for + every local interface and every BGP peer. + +2.2. Open Message Error Handling + + For a BGP speaker that supports the AS-wide Unique BGP Identifier, + the OPEN message error handling related to the BGP Identifier is + modified as follows: + + If the BGP Identifier field of the OPEN message is zero, or if it + is the same as the BGP Identifier of the local BGP speaker and the + message is from an internal peer, then the Error Subcode is set to + "Bad BGP Identifier". + + + + + + + + + + +Chen & Yuan Standards Track [Page 2] + +RFC 6286 AS-Wide Unique BGP ID for BGP-4 June 2011 + + +2.3. Connection Collision Resolution + + For a BGP speaker that supports the AS-wide Unique BGP Identifier, + the procedures for connection collision resolution are extended as + follows to deal with the case in which the two BGP speakers share the + same BGP Identifier (thus, it is only applicable to an external + peer): + + If the BGP Identifiers of the peers involved in the connection + collision are identical, then the connection initiated by the BGP + speaker with the larger AS number is preserved. + + This extension covers cases in which the 4-octet AS numbers are + involved [RFC4893]. + +3. Remarks + + It is noted that a BGP Identifier allocated based on [RFC4271] fits + the revised definition. + + In case of BGP Confederation, the whole confederation is considered + as one AS for the purpose of supporting the AS-wide Unique BGP + Identifier. + + A BGP speaker that supports the AS-wide Unique BGP Identifier cannot + share a BGP Identifier with its external neighbor until the remote + BGP speaker is upgraded with software that supports the specified + revisions. + + In addition to the OPEN message, the BGP Identifier is currently also + used in the following areas: + + o In the AGGREAGTOR attribute of a route where the combination of a + BGP Identifier and an AS number uniquely identifies the BGP speaker + that performs the route aggregation. + + o In the Route Reflection within an AS, where only the BGP Identifier + of an internal neighbor may be propagated in the route reflection + related attributes. + + o In the route selection, where the BGP Identifier is not used in + comparing a route from an internal neighbor and a route from an + external neighbor. In addition, routes from BGP speakers with + identical BGP Identifiers have been dealt with (e.g., parallel BGP + sessions between two BGP speakers). + + + + + + +Chen & Yuan Standards Track [Page 3] + +RFC 6286 AS-Wide Unique BGP ID for BGP-4 June 2011 + + + Therefore, it is concluded that the revisions specified in this + document do not introduce any backward compatibility issues with the + current usage of the BGP Identifier. + +4. Security Considerations + + This extension to BGP does not introduce new security considerations. + BGP security considerations are discussed in [RFC4271]. + +5. Acknowledgments + + The authors would like to thank members of the IDR Working Group for + discussions on the "IPv6-only Network" related issues that inspired + this document. + +6. Normative References + + [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A Border + Gateway Protocol 4 (BGP-4)", RFC 4271, January 2006. + + [RFC4893] Vohra, Q. and E. Chen, "BGP Support for Four-octet AS + Number Space", RFC 4893, May 2007. + +Authors' Addresses + + Enke Chen + Cisco Systems, Inc. + 170 W. Tasman Dr. + San Jose, CA 95134 + + EMail: enkechen@cisco.com + + Jenny Yuan + Cisco Systems, Inc. + 170 W. Tasman Dr. + San Jose, CA 95134 + + EMail: jenny@cisco.com + + + + + + + + + + + + + +Chen & Yuan Standards Track [Page 4] + -- cgit v1.2.3