IPv6 Address Specific BGP Extended Community Attribute
draft-ietf-l3vpn-v6-ext-communities-02

Network Working Group                               Yakov Rekhter
Internet Draft                                   Juniper Networks
Expiration Date: June 2009 
Intended Status: Proposed Standard

        IPv6 Address Specific BGP Extended Communities Attribute

               draft-ietf-l3vpn-v6-ext-communities-02.txt

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Abstract

   Current specifications of BGP Extended Communities [RFC4360] support
   IPv4 Address Specific Extended Community, but do not support IPv6
   Address Specific Extended Community. The lack of 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. This document defines a new
   BGP attribute, 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.

Specification of Requirements

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].

1. Introduction

   Current specifications of BGP Extended Communities [RFC4360] support
   IPv4 Addres Specific Extended Community, but do not support IPv6
   Address Specific Extended Community. The lack of 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, IPv6 Address Specific Extended Community
   that has 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.

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2. IPv6 Address Specific BGP Extended Communities Attribute

   The IPv6 Address Specific Extended Communities 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 Communities 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 twenty
   octets quantity, as follows:

      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

     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     | 0x00 or 0x40  |    Sub-Type   |    Global Administrator       |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |          Global Administrator (cont.)                         |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |          Global Administrator (cont.)                         |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |          Global Administrator (cont.)                         |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     | Global Administrator (cont.)  |    Local Administrator        |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The first high-order octet indicates whether a particular Sub-type of
   this community is transitive across ASes (0x00), or not (0x40).  The
   second high-order octet of this extended type is used to indicate
   Sub-types. The Sub-types are the same as for IPv4 Address Specific
   extended community.

      Global Administrator field: 16 octets

         This field contains an IPv6 unicast address assigned by one of
         the Internet registries.

      Local Administrator: 2 octets

         The organization which has been assigned the IPv6 address in
         the Global Administrator field, can encode any information in

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         this field.  The format and meaning of this value encoded in
         this field should be defined by the sub-type of the community.

3. IANA Considerations

   This document defines a new BGP attribute, called IPv6 Address Spe-
   cific Extended Community.

   This document defines a class of extended communities called IPv6
   Address Specific extended community for which the IANA is to create
   and maintain a registry entitled "IPv6 Address Specific Extended Com-
   munity".  Future assignment are to be made using the "First Come
   First Served" policy defined in [RFC5226]. The Type values for the
   transitive communities of the IPv6 Address Specific Extended Commu-
   nity class are 0x0000-0x00ff, and for the non-transitive communities
   of that class are 0x4000-0x40ff. Assignments consist of a name and
   the value.

   This document makes the following assignments for the IPv6 Address
   Specific extended community types:

      Name                                     Type Value
      ----                                     --------------
      IPv6 address specific Route Target       0x0002
      IPv6 address specific Route Origin       0x0003

4. Security Considerations

   All the security considerations for BGP Extended Communities apply
   here.

5. Acknowledgements

   Many thanks to Michael Lundberg and Emre Ertekin for their review and
   comments.

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6. Normative References

   [BGP-4] Rekhter, Y., and T. Li, "A Border Gateway Protocol 4
   (BGP-4)", RFC 4271, January 2006

   [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
   Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC5226] Narten, T., Alvestrand, H., "Guidelines for Writing an IANA
   Considerations Section in RFCs", RFC5226, May 2008.

   [RFC4360] Sangli, S., Tappan, D., and Y. Rekhter, "BGP Extended Com-
   munities Attribute", RFC 4360, February 2006.

7. Non-normative References

8. Author Information

   Yakov Rekhter
   Juniper Networks, Inc.
   e-mail: yakov@juniper.net

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