datatracker.ietf.org
Sign in
Version 5.3.0, 2014-04-12
Report a bug

Autonomous System Confederations for BGP
RFC 5065

Document type: RFC - Draft Standard (August 2007; Errata)
Obsoletes RFC 3065
Document stream: IETF
Last updated: 2013-03-02
Other versions: plain text, pdf, html

IETF State: (None)
Consensus: Unknown
Document shepherd: No shepherd assigned

IESG State: RFC 5065 (Draft Standard)
Responsible AD: Bill Fenner
Send notices to: idr-chairs@tools.ietf.org

Network Working Group                                          P. Traina
Request for Comments: 5065                            Blissfully Retired
Obsoletes: 3065                                             D. McPherson
Category: Standards Track                                 Arbor Networks
                                                              J. Scudder
                                                        Juniper Networks
                                                             August 2007

                Autonomous System Confederations for BGP

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 IETF Trust (2007).

Abstract

   The Border Gateway Protocol (BGP) is an inter-autonomous system
   routing protocol designed for Transmission Control Protocol/Internet
   Protocol (TCP/IP) networks.  BGP requires that all BGP speakers
   within a single autonomous system (AS) must be fully meshed.  This
   represents a serious scaling problem that has been well documented in
   a number of proposals.

   This document describes an extension to BGP that may be used to
   create a confederation of autonomous systems that is represented as a
   single autonomous system to BGP peers external to the confederation,
   thereby removing the "full mesh" requirement.  The intention of this
   extension is to aid in policy administration and reduce the
   management complexity of maintaining a large autonomous system.

   This document obsoletes RFC 3065.

Traina, et al.              Standards Track                     [Page 1]
RFC 5065                                                     August 2007

Table of Contents

   1. Introduction ....................................................3
      1.1. Specification of Requirements ..............................3
      1.2. Terminology ................................................3
   2. Discussion ......................................................4
   3. AS_CONFED Segment Type Extension ................................5
   4. Operation .......................................................5
      4.1. AS_PATH Modification Rules .................................6
   5. Error Handling ..................................................8
      5.1. Error Handling .............................................8
      5.2. MED and LOCAL_PREF Handling ................................8
      5.3. AS_PATH and Path Selection .................................9
   6. Compatibility Considerations ...................................10
   7. Deployment Considerations ......................................10
   8. Security Considerations ........................................10
   9. Acknowledgments ................................................11
   10. References ....................................................11
      10.1. Normative References .....................................11
      10.2. Informative References ...................................11
   Appendix A. Aggregate Routing Information .........................13
   Appendix B. Changes from RFC 3065 .................................13

Traina, et al.              Standards Track                     [Page 2]
RFC 5065                                                     August 2007

1.  Introduction

   As originally defined, BGP requires that all BGP speakers within a
   single AS must be fully meshed.  The result is that for n BGP
   speakers within an AS, n*(n-1)/2 unique Internal BGP (IBGP) sessions
   are required.  This "full mesh" requirement clearly does not scale
   when there are a large number of IBGP speakers within the autonomous
   system, as is common in many networks today.

   This scaling problem has been well documented and a number of
   proposals have been made to alleviate this, such as [RFC2796] and
   [RFC1863] (made historic by [RFC4223]).  This document presents
   another alternative alleviating the need for a "full mesh" and is
   known as "Autonomous System Confederations for BGP", or simply, "BGP
   confederations".  It has also been observed that BGP confederations
   may provide improvements in routing policy control.

   This document is a revision of, and obsoletes, [RFC3065], which is
   itself a revision of [RFC1965].  It includes editorial changes,
   terminology clarifications, and more explicit protocol specifications

[include full document text]