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RFC 7153 - IANA Registries for BGP Extended Communities


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Internet Engineering Task Force (IETF)                          E. Rosen
Request for Comments: 7153                           Cisco Systems, Inc.
Updates: 4360, 5701                                           Y. Rekhter
Category: Standards Track                         Juniper Networks, Inc.
ISSN: 2070-1721                                               March 2014

              IANA Registries for BGP Extended Communities

Abstract

   This document reorganizes the IANA registries for the type values and
   sub-type values of the BGP Extended Communities attribute and the BGP
   IPv6-Address-Specific Extended Communities attribute.  This is done
   in order to remove interdependencies among the registries, thus
   making it easier for IANA to determine which codepoints are available
   for assignment in which registries.  This document also clarifies the
   information that must be provided to IANA when requesting an
   allocation from one or more of these registries.  These changes are
   compatible with the existing allocations and thus do not affect
   protocol implementations.  The changes will, however, impact the
   "IANA Considerations" sections of future protocol specifications.
   This document updates RFC 4360 and RFC 5701.

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc7153.

Copyright Notice

   Copyright (c) 2014 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 Simplified BSD License.

Table of Contents

   1. Introduction ....................................................3
   2. Types, Sub-Types, and Registries ................................4
   3. Applicability to IPv6-Address-Specific EC Attribute .............4
   4. How to Request EC Type and/or Sub-Type Codepoints ...............5
   5. IANA Considerations .............................................6
      5.1. Registries for the "Type" Field ............................7
           5.1.1. Transitive Types ....................................7
           5.1.2. Non-Transitive Types ................................8
      5.2. Registries for the "Sub-Type" Field ........................9
           5.2.1. EVPN Extended Community Sub-Types ...................9
           5.2.2. Transitive Two-Octet AS-Specific Extended Community
                  Sub-Types ..........................................10
           5.2.3. Non-Transitive Two-Octet AS-Specific Extended
                  Community Sub-Types ................................10
           5.2.4. Transitive Four-Octet AS-Specific Extended
                  Community Sub-Types ................................11
           5.2.5. Non-Transitive Four-Octet AS-Specific Extended
                  Community Sub-Types ................................11
           5.2.6. Transitive IPv4-Address-Specific Extended Community
                  Sub-Types ..........................................12
           5.2.7. Non-Transitive IPv4-Address-Specific Extended
                  Community Sub-Types ................................12
           5.2.8. Transitive Opaque Extended Community Sub-Types .....13
           5.2.9. Non-Transitive Opaque Extended Community
                  Sub-Types ..........................................13
           5.2.10. Generic Transitive Experimental Use Extended
                   Community Sub-Types ...............................14
           5.2.11. Registries for the "Value" Field ..................14
                  5.2.11.1. Traffic Action Fields ....................14
      5.3. Registries for IPv6-Address-Specific ECs ..................15
           5.3.1. Transitive Types ...................................15
           5.3.2. Non-Transitive Types ...............................15
   6. Security Considerations ........................................15
   7. Acknowledgments ................................................16
   8. Normative References ...........................................16

1.  Introduction

   RFC 4360 [RFC4360] defines the BGP "Extended Communities" (EC)
   attribute.  This attribute consists of a sequence of eight-octet
   "extended communities".  The high-order octet is defined to be the
   "Type" field.  Each Type has a range of values for "Transitive
   Extended Community Types" and a range of values for "Non-transitive
   Extended Community Types".  Some of these ranges are further
   subdivided into a sub-range of values to be assigned by IANA under
   the "Standards Action" policy, a sub-range of values to be assigned

   by IANA under the "First Come First Served" policy, and a sub-range
   for "experimental use".  (See [RFC5226], [RFC7120], and [RFC3692] for
   an explanation of these policies.)

   For some Extended Community Types, the second octet of the Extended
   Community is a "Sub-Type" field, and the remaining six octets are the
   "Value" field.  These are referred to as "Extended Types".  For other
   types, there is no "Sub-Type" field, and the "Value" field contains
   seven octets.  These are referred to as "Regular Types".

   RFC 4360 is not very specific about how the IANA registries for
   Extended Community Types and/or Sub-Types are to be organized, and
   this has led to some confusion.  The purpose of this document is to
   reorganize the registries to make the IANA codepoint allocation task
   more straightforward.

2.  Types, Sub-Types, and Registries

   The high-order octet of an Extended Community will be known as the
   "Type" field.

   There will be one IANA registry for "Transitive Extended Community
   Types" (see Section 5.1.1) and one for "Non-transitive Extended
   Community Types" (Section 5.1.2).  Each registry specifies three
   ranges, and each range is associated with a particular IANA
   allocation policy.

   There will be a set of IANA registries for Extended Community
   Sub-Types (see Section 5.2).  Each such registry will have a range of
   0x00-0xFF.  Values in the range 0x00-0xBF are assignable by IANA
   according to the "First Come First Served" allocation policy of
   [RFC5226].  Values in the range 0xC0-0xFF are assignable by IANA
   according to the "IETF Review" allocation policy of [RFC5226].

   If a particular Type has Sub-Types, that Type's entry in its Type
   registry identifies its Sub-Type registry.  Note that some Types do
   not have Sub-Types.  When the request is made to establish a new Type
   registry, the request must specify whether or not there is to be a
   Sub-Type registry associated with that Type.

   Whether a given Type has Sub-Types is determined when the Type is
   initially defined; this cannot be changed later.

3.  Applicability to IPv6-Address-Specific EC Attribute

   RFC 5701 [RFC5701] defines the IPv6-Address-Specific Extended
   Community to be a 20-octet quantity whose high-order two octets may
   be considered to be the "Type" field.  The high-order octet is either

   0x00, indicating a transitive Extended Community; or 0x40, indicating
   a Non-transitive Extended Community.  The second octet is said to be
   a "Sub-Type", and it is suggested that the Sub-Types are the same as
   the Sub-Types for the IPv4-Address-Specific Extended Community.
   However, the existing IANA codepoint allocations for this octet do
   not always match the corresponding allocations for the
   IPv4-Address-Specific Extended Community Sub-Types.

   This document modifies RFC 5701 by removing any requirement for the
   values of the second octet of the IPv6-Address-Specific Extended
   Community Type codepoints to match the codepoints in either of the
   IPv4-Address-Specific Sub-Types registries.

   This document requests IANA to create two IPv6-Address-Specific
   Extended Community registries -- one for transitive communities and
   one for non-transitive communities.  See Section 5.3.

4.  How to Request EC Type and/or Sub-Type Codepoints

   When a codepoint is needed for a new Extended Community, the
   requester should first determine whether an existing Type can be
   used.  If so, IANA should be asked to allocate a codepoint from the
   corresponding Sub-Type registry, if there is one.

   If a new Extended Community Type is needed, the requester should ask
   IANA to allocate a new type from the "BGP Transitive Extended
   Community Types" registry, the "BGP Non-Transitive Extended Community
   Types" registry, or both.  It is up to the requester to state whether
   an allocation is needed from one or both of these registries.  When
   an allocation from both registries is requested, the requester may
   find it desirable for both allocations to share the same low-order
   six bits.  If so, it is the responsibility of the requester to
   explicitly request this of IANA.

   Of course, any request for a codepoint from a particular registry
   must follow the defined registration procedures for that registry.

   If a new Extended Community Type is needed and the new Type is to
   have Sub-Types, the requester should specify whether an existing
   Sub-Type registry can be used for the new Type or a new Sub-Type
   registry is needed.  (At the current time, every Type that has
   Sub-Types is associated with a unique Sub-Type registry.  It is
   possible that in the future a new Type registry may be created that
   is associated with a pre-existing Sub-Type registry.)  In either
   case, if a new Sub-Type value needs to be allocated from a particular
   Sub-Type registry, the request should explicitly identify the
   registry.

   If the creation of a new Sub-Type registry is requested, the range of
   values is always 0x00-0xFF.  It is recommended that the allocation
   policy described in Section 2 be used, i.e., 0x00-0xBF to be
   allocated by IANA under the "First Come First Served" policy and
   0xC0-0xFF to be allocated by IANA under the "IETF Review" policy.

   Commonly, a new Extended Community is defined such that it can be of
   several Types.  For example, one may want to define a new Extended
   Community so that it can be either transitive or non-transitive,
   either the two-octet AS Number Type or the four-octet AS Number Type,
   etc.  The requester is responsible for explicitly asking IANA to
   allocate codepoints in all the necessary Type and/or Sub-Type
   registries.

   When a new Extended Community is defined, it may be necessary to ask
   IANA to allocate codepoints in several Sub-Type registries.  In this
   case, it is a common practice to ask IANA to allocate the same
   codepoint value in each registry.  If this is desired, it is the
   responsibility of the requester to explicitly ask IANA to allocate
   the same value in each registry.

   When a new Extended Community Sub-Type codepoint is allocated, it may
   also be desirable to allocate a corresponding value in one or both of
   the IPv6-Address-Specific Extended Community registries.  The
   requester is responsible for requesting this allocation explicitly.
   If the requester would like the same numerical value to be allocated
   in an IPv6-Address-Specific Extended Community registry that is
   allocated in some other registry, it is the responsibility of the
   requester to explicitly ask this of IANA.

5.  IANA Considerations

   IANA has replaced the pre-existing BGP Extended Communities
   registries with the registries described in this section.

   The registries reproduced below do not include the "references" or
   "date" fields for the individual codepoints in the registries,
   because it is difficult to incorporate those within the 72-character
   line limitation of RFCs.  The references and associated dates have
   been copied from the existing registries when creating the new
   registries; the authors have worked with IANA to ensure that this
   information has been carried over correctly to the reorganized
   registry.  As this document does not change the usage or semantics of
   any of the codepoints, the references associated with the individual
   codepoints do not change.

   On the other hand, the references for each of the registries defined
   in this section have been changed to refer to this document.

5.1.  Registries for the "Type" Field

5.1.1.  Transitive Types

   The following note has been added to the "BGP Transitive Extended
   Community Types" registry.

      This registry contains values of the high-order octet (the "Type"
      field) of a Transitive Extended Community.

   Registry Name: BGP Transitive Extended Community Types

      RANGE            REGISTRATION PROCEDURES

      0x00-0x3F        First Come First Served
      0x80-0x8F        Experimental Use (see RFC 3692)
      0x90-0xBF        Standards Action

      TYPE VALUE       NAME

      0x00             Transitive Two-Octet AS-Specific Extended
                       Community (Sub-Types are defined in the
                       "Transitive Two-Octet AS-Specific Extended
                       Community Sub-Types" registry)

      0x01             Transitive IPv4-Address-Specific Extended
                       Community (Sub-Types are defined in the
                       "Transitive IPv4-Address-Specific Extended
                       Community Sub-Types" registry)

      0x02             Transitive Four-Octet AS-Specific Extended
                       Community (Sub-Types are defined in the
                       "Transitive Four-Octet AS-Specific Extended
                       Community Sub-Types" registry)

      0x03             Transitive Opaque Extended Community
                       (Sub-Types are defined in the "Transitive
                       Opaque Extended Community Sub-Types"
                       registry)

      0x04             QoS Marking

      0x05             CoS Capability

      0x06             EVPN (Sub-Types are defined in the "EVPN
                       Extended Community Sub-Types" registry)

      0x08             Flow spec redirect/mirror to IP next-hop

      0x80             Generic Transitive Experimental Use Extended
                       Community (Sub-Types are defined in the
                       "Generic Transitive Experimental Use Extended
                       Community Sub-Types" registry)

5.1.2.  Non-Transitive Types

   The following note has been added to the "BGP Non-Transitive Extended
   Community Types" registry.

      This registry contains values of the high-order octet (the "Type"
      field) of a Non-transitive Extended Community.

   Registry Name: BGP Non-Transitive Extended Community Types

      RANGE            REGISTRATION PROCEDURES

      0x40-0x7F        First Come First Served
      0xC0-0xCF        Experimental Use (see RFC 3692)
      0xD0-0xFF        Standards Action

      TYPE VALUE       NAME

      0x40             Non-Transitive Two-Octet AS-Specific Extended
                       Community (Sub-Types are defined in the
                       "Non-Transitive Two-Octet AS-Specific Extended
                       Community Sub-Types" registry)

      0x41             Non-Transitive IPv4-Address-Specific Extended
                       Community (Sub-Types are defined in the
                       "Non-Transitive IPv4-Address-Specific Extended
                       Community Sub-Types" registry)

      0x42             Non-Transitive Four-Octet AS-Specific Extended
                       Community (Sub-Types are defined in the
                       "Non-Transitive Four-Octet AS-Specific Extended
                       Community Sub-Types" registry)

      0x43             Non-Transitive Opaque Extended Community
                       (Sub-Types are defined in the "Non-Transitive
                       Opaque Extended Community Sub-Types" registry)

      0x44             QoS Marking

5.2.  Registries for the "Sub-Type" Field

5.2.1.  EVPN Extended Community Sub-Types

   The following note has been added to the "EVPN Extended Community
   Sub-Types" registry:

      This registry contains values of the second octet (the "Sub-Type"
      field) of an extended community when the value of the first octet
      (the "Type" field) is 0x06.

   Registry Name: EVPN Extended Community Sub-Types

      RANGE              REGISTRATION PROCEDURE

      0x00-0xBF          First Come First Served
      0xC0-0xFF          IETF Review

      SUB-TYPE VALUE     NAME

      0x00               MAC Mobility
      0x01               ESI MPLS Label
      0x02               ES Import

5.2.2.  Transitive Two-Octet AS-Specific Extended Community Sub-Types

   The following note has been added to the "Transitive Two-Octet
   AS-Specific Extended Community Sub-Types" registry:

      This registry contains values of the second octet (the "Sub-Type"
      field) of an extended community when the value of the first octet
      (the "Type" field) is 0x00.

   Registry Name: Transitive Two-Octet AS-Specific Extended
                  Community Sub-Types

      RANGE              REGISTRATION PROCEDURE

      0x00-0xBF          First Come First Served
      0xC0-0xFF          IETF Review

      SUB-TYPE VALUE     NAME

      0x02               Route Target
      0x03               Route Origin
      0x05               OSPF Domain Identifier
      0x08               BGP Data Collection
      0x09               Source AS
      0x0A               L2VPN Identifier
      0x10               Cisco VPN-Distinguisher

5.2.3.  Non-Transitive Two-Octet AS-Specific Extended Community
        Sub-Types

   The following note has been added to the "Non-Transitive Two-Octet
   AS-Specific Extended Community Sub-Types" registry:

      This registry contains values of the second octet (the "Sub-Type"
      field) of an extended community when the value of the first octet
      (the "Type" field) is 0x40.

   Registry Name: Non-Transitive Two-Octet AS-Specific Extended
                  Community Sub-Types

      RANGE              REGISTRATION PROCEDURE

      0x00-0xBF          First Come First Served
      0xC0-0xFF          IETF Review

      SUB-TYPE VALUE     NAME

      0x04               Link Bandwidth Extended Community

5.2.4.  Transitive Four-Octet AS-Specific Extended Community Sub-Types

   The following note has been added to the "Transitive Four-Octet
   AS-Specific Extended Community Sub-Types" registry:

      This registry contains values of the second octet (the "Sub-Type"
      field) of an extended community when the value of the first octet
      (the "Type" field) is 0x02.

   Registry Name: Transitive Four-Octet AS-Specific Extended
                  Community Sub-Types

      RANGE              REGISTRATION PROCEDURE

      0x00-0xBF          First Come First Served
      0xC0-0xFF          IETF Review

      SUB-TYPE VALUE     NAME

      0x02               Route Target
      0x03               Route Origin
      0x04               Generic
      0x05               OSPF Domain Identifier
      0x08               BGP Data Collection
      0x09               Source AS
      0x10               Cisco VPN Identifier

5.2.5.  Non-Transitive Four-Octet AS-Specific Extended Community
        Sub-Types

   The following note has been added to the "Non-Transitive Four-Octet
   AS-Specific Extended Community Sub-Types" registry:

      This registry contains values of the second octet (the "Sub-Type"
      field) of an extended community when the value of the first octet
      (the "Type" field) is 0x42.

   Registry Name: Non-Transitive Four-Octet AS-Specific
                  Extended Community Sub-Types

      RANGE              REGISTRATION PROCEDURE

      0x00-0xBF          First Come First Served
      0xC0-0xFF          IETF Review

      SUB-TYPE VALUE     NAME

      0x04               Generic

5.2.6.  Transitive IPv4-Address-Specific Extended Community Sub-Types

   The following note has been added to the "Transitive
   IPv4-Address-Specific Extended Community Sub-Types" registry:

      This registry contains values of the second octet (the "Sub-Type"
      field) of an extended community when the value of the first octet
      (the "Type" field) is 0x01.

   Registry Name: Transitive IPv4-Address-Specific Extended
                  Community Sub-Types

      RANGE              REGISTRATION PROCEDURE

      0x00-0xBF          First Come First Served
      0xC0-0xFF          IETF Review

      SUB-TYPE VALUE     NAME

      0x02               Route Target
      0x03               Route Origin
      0x05               OSPF Domain Identifier
      0x07               OSPF Route ID
      0x0A               L2VPN Identifier
      0x0B               VRF Route Import
      0x10               Cisco VPN-Distinguisher

5.2.7.  Non-Transitive IPv4-Address-Specific Extended Community
        Sub-Types

   The following note has been added to the "Non-Transitive
   IPv4-Address-Specific Extended Community Sub-Types" registry:

      This registry contains values of the second octet (the "Sub-Type"
      field) of an extended community when the value of the first octet
      (the "Type" field) is 0x41.

   Registry Name: Non-Transitive IPv4-Address-Specific Extended
                  Community Sub-Types

      RANGE            REGISTRATION PROCEDURE

      0x00-0xBF        First Come First Served
      0xC0-0xFF        IETF Review

      None Assigned

5.2.8.  Transitive Opaque Extended Community Sub-Types

   The following note has been added to the "Transitive Opaque Extended
   Community Sub-Types" registry:

      This registry contains values of the second octet (the "Sub-Type"
      field) of an extended community when the value of the first octet
      (the "Type" field) is 0x03.

   Registry Name: Transitive Opaque Extended Community
                  Sub-Types

       RANGE             REGISTRATION PROCEDURE

       0x00-0xBF         First Come First Served
       0xC0-0xFF         IETF Review

       SUB-TYPE VALUE    NAME

       0x06              OSPF Route Type
       0x0B              Color Extended Community
       0x0C              Encapsulation Extended Community
       0x0D              Default Gateway

5.2.9.  Non-Transitive Opaque Extended Community Sub-Types

   The following note has been added to the "Non-Transitive Opaque
   Extended Community Sub-Types" registry:

      This registry contains values of the second octet (the "Sub-Type"
      field) of an extended community when the value of the first octet
      (the "Type" field) is 0x43.

   Registry Name: Non-Transitive Opaque Extended Community
                  Sub-Types

      RANGE              REGISTRATION PROCEDURE

      0x00-0xBF          First Come First Served
      0xC0-0xFF          IETF Review

      SUB-TYPE VALUE     NAME

      0x00               BGP Origin Validation State

5.2.10.  Generic Transitive Experimental Use Extended Community
         Sub-Types

   The following note has been added to the "Generic Transitive
   Experimental Use Extended Community Sub-Types" registry:

      This registry contains values of the second octet (the "Sub-Type"
      field) of an extended community when the value of the first octet
      (the "Type" field) is 0x80.

   Registry Name: Generic Transitive Experimental Use Extended Community
   Sub-Types

      RANGE              REGISTRATION PROCEDURE

      0x00-0xBF          First Come First Served
      0xC0-0xFF          IETF Review

      SUB-TYPE VALUE     NAME

      0x06               Flow spec traffic-rate
      0x07               Flow spec traffic-action (Use of the
                         "Value" field is defined in the
                         "Traffic Action Fields" registry)
      0x08               Flow spec redirect
      0x09               Flow spec traffic-remarking
      0x0A               Layer2 Info Extended Community

   Note: RFC 5575 contains narrative text that declares the "Flow spec
   traffic-rate" to be non-transitive but then assigns it a codepoint
   that indicates that it is transitive.  Addressing this error in
   RFC 5575 is not within the scope of this document.

5.2.11.  Registries for the "Value" Field

   At the time of the writing of this document, there is only one
   registry containing codepoints for the "Value" field of an Extended
   Community.

5.2.11.1.  Traffic Action Fields

   This registry has not been modified.

5.3.  Registries for IPv6-Address-Specific ECs

5.3.1.  Transitive Types

   The following note has been added to the "Transitive
   IPv6-Address-Specific Extended Community Types" registry:

      This registry contains values of the two high-order octets of an
      IPv6-Address-Specific Extended Community.

   Registry Name: Transitive IPv6-Address-Specific Extended
                  Community Types

      RANGE              REGISTRATION PROCEDURE

      0x0000-0x00FF      First Come First Served

      TYPE VALUE         NAME

      0x0002             Route Target
      0x0003             Route Origin
      0x0004             OSPFv3 Route Attributes (deprecated)
      0x000B             VRF Route Import
      0x0010             Cisco VPN-Distinguisher
      0x0011             UUID-based Route Target

5.3.2.  Non-Transitive Types

   The following note has been added to the "Non-Transitive
   IPv6-Address-Specific Extended Community Types" registry:

      This registry contains values of the two high-order octets of an
      IPv6-Address-Specific Extended Community.

   Registry Name: Non-Transitive IPv6-Address-Specific Extended
                  Community Types

      RANGE              REGISTRATION PROCEDURE

      0x4000-0x40FF      First Come First Served

      None assigned

6.  Security Considerations

   No security considerations are raised by this document.

7.  Acknowledgments

   The authors wish to thank Jon Mitchell, Hyojeong Kim, and Pearl Liang
   for their review and comments.

   The authors wish to thank Amanda Baber of IANA for educating us on
   some of the problems faced by IANA staff when responding to requests
   for BGP Extended Community Type and Sub-Type codepoint allocations.

8.  Normative References

   [RFC3692]  Narten, T., "Assigning Experimental and Testing Numbers
              Considered Useful", BCP 82, RFC 3692, January 2004.

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

   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 5226,
              May 2008.

   [RFC5701]  Rekhter, Y., "IPv6 Address Specific BGP Extended Community
              Attribute", RFC 5701, November 2009.

   [RFC7120]  Cotton, M., "Early IANA Allocation of Standards Track Code
              Points", BCP 100, RFC 7120, January 2014.

Authors' Addresses

   Yakov Rekhter
   Juniper Networks
   1194 North Mathilda Ave.
   Sunnyvale, CA  94089

   EMail: yakov@juniper.net

   Eric C. Rosen
   Cisco Systems, Inc.
   1414 Massachusetts Avenue
   Boxborough, MA  01719

   EMail: erosen@cisco.com

 

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