RFC 1965 (rfc1965) - Page 1 of 7


Autonomous System Confederations for BGP



Alternative Format: Original Text Document



Network Working Group                                          P. Traina
Request for Comments: 1965                                 cisco Systems
Category: Experimental                                         June 1996


                Autonomous System Confederations for BGP

Status of this Memo

   This memo defines an Experimental Protocol for the Internet
   community.  This memo does not specify an Internet standard of any
   kind.  Discussion and suggestions for improvement are requested.
   Distribution of this memo is unlimited.

Abstract

   Border Gateway Protocol [1] is an inter-autonomous system routing
   protocol designed for TCP/IP networks.

   This document describes an extension to BGP which may be used to
   create a confederation of autonomous systems which is represented as
   one single autonomous system to BGP peers external to the
   confederation.

   The intention of this extension is to aid in policy administration
   and reduce the management complexity of maintaining a large
   autonomous system.

   The extension this document describes is widely deployed in the
   Internet today.

Introduction

   It may be useful to subdivide autonomous systems with a very large
   number of BGP speakers into smaller domains for purposes of
   controlling routing policy via information contained in the BGP
   AS_PATH attribute.  For example, one may chose to consider all BGP
   speakers in a geographic region as a single entity.

   In addition to improvements in routing policy control, current
   techniques for deploying BGP among speakers in the same autonomous
   system establish a full mesh of TCP connections among all speakers
   for the purpose of exchanging exterior routing information.  In
   autonomous systems the number of intra-domain connections that need
   to be maintained by each border router can become significant.

   Subdividing a large autonomous system allows a significant reduction
   in the total number of intra-domain BGP connections, as the



Traina                        Experimental