IPv6 Address Specific BGP Extended Community Attribute
RFC 5701

Network Working Group                                         Y. Rekhter
Request for Comments: 5701                              Juniper Networks
Category: Standards Track                                  November 2009

         IPv6 Address Specific BGP Extended Community Attribute

Abstract

   Current specifications of BGP Extended Communities (RFC 4360) support
   the IPv4 Address Specific Extended Community, but do not support an
   IPv6 Address Specific Extended Community.  The lack of an IPv6
   Address Specific Extended Community may be a problem when an
   application uses the IPv4 Address Specific Extended Community, and
   one wants to use this application in a pure IPv6 environment.  This
   document defines a new BGP attribute, the IPv6 Address Specific
   Extended Community, that addresses this problem.  The IPv6 Address
   Specific Extended Community is similar to the IPv4 Address Specific
   Extended Community, except that it carries an IPv6 address rather
   than an IPv4 address.

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) 2009 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 BSD License.

   This document may contain material from IETF Documents or IETF
   Contributions published or made publicly available before November
   10, 2008.  The person(s) controlling the copyright in some of this
   material may not have granted the IETF Trust the right to allow

Rekhter                     Standards Track                     [Page 1]
RFC 5701       IPv6 Specific Extended Community Attribute  November 2009

   modifications of such material outside the IETF Standards Process.
   Without obtaining an adequate license from the person(s) controlling
   the copyright in such materials, this document may not be modified
   outside the IETF Standards Process, and derivative works of it may
   not be created outside the IETF Standards Process, except to format
   it for publication as an RFC or to translate it into languages other
   than English.

1.  Introduction

   Current specifications of BGP Extended Communities [RFC4360] support
   the IPv4 Address Specific Extended Community, but do not support an
   IPv6 Address Specific Extended Community.  The lack of an IPv6
   Address Specific Extended Community may be a problem when an
   application uses IPv4 Address Specific Extended Community and one
   wants to use this application in a pure IPv6 environment.

   Because the BGP Extended Community attribute defines each BGP
   Extended Community as being 8 octets long, it is not possible to
   define the IPv6 Specific Extended Community using the existing BGP
   Extended Community attribute [RFC4360].  Therefore, this document
   defines a new BGP attribute, the IPv6 Address Specific Extended
   Community, that has a structure similar to the IPv4 Address Specific
   Extended Community, and thus could be used in a pure IPv6 environment
   as a replacement of the IPv4 Address Specific Extended Community.

2.  IPv6 Address Specific BGP Extended Community Attribute

   The IPv6 Address Specific Extended Community Attribute is a
   transitive, optional BGP attribute [BGP-4].  The attribute consists
   of a set of "IPv6 Address Specific extended communities".  All routes
   with the IPv6 Address Specific Extended Community attribute belong to
   the communities listed in the attribute.

   Just like all other BGP Extended Communities, the IPv6 Address
   Specific Extended Community supports multiple sub-types.

   Each IPv6 Address Specific extended community is encoded as a
   20-octet quantity, as follows:

Rekhter                     Standards Track                     [Page 2]
RFC 5701       IPv6 Specific Extended Community Attribute  November 2009

    0                   1                   2                   3
    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1