RFC 2842 (rfc2842) - Page 1 of 5

Capabilities Advertisement with BGP-4

Alternative Format: Original Text Document
Next >
Network Working Group                                        R. Chandra
Request for Comments: 2842                        Redback Networks Inc.
Category: Standards Track                                    J. Scudder
                                                          cisco Systems
                                                               May 2000


                 Capabilities Advertisement with BGP-4

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 (2000).  All Rights Reserved.

Abstract

   Currently BGP-4 [BGP-4] requires that when a BGP speaker receives an
   OPEN message with one or more unrecognized Optional Parameters, the
   speaker must terminate BGP peering. This complicates introduction of
   new capabilities in BGP.

   This document defines new Optional Parameter, called Capabilities,
   that is expected to facilitate introduction of new capabilities in
   BGP by providing graceful capability advertisement without requiring
   that BGP peering be terminated.

1. Overview of Operations

   When a BGP speaker that supports capabilities advertisement sends an
   OPEN message to its BGP peer, the message may include an Optional
   Parameter, called Capabilities. The parameter lists the capabilities
   supported by the speaker.

   A BGP speaker determines the capabilities supported by its peer by
   examining the list of capabilities present in the Capabilities
   Optional Parameter carried by the OPEN message that the speaker
   receives from the peer.

   A BGP speaker that supports a particular capability may use this
   capability with its peer after the speaker determines (as described
   above) that the peer supports this capability.



Chandra & Scudder           Standards Track
Next >