BESS Working Group                                              E. Rosen
Internet-Draft                                    Juniper Networks, Inc.
Updates: 6514 (if approved)                                     T. Morin
Intended status: Standards Track                                  Orange
Expires: August 5, 2016                                 February 7, 2, 2016                                 August 6, 2015

                      Registry and Extensions for
          P-Multicast Service Interface Tunnel Attribute Flags
                    draft-ietf-bess-pta-flags-01.txt
                    draft-ietf-bess-pta-flags-02.txt

Abstract

   RFC6514 defines

   The BGP-based control procedures for Multicast Virtual Private
   Networks make use of a BGP attribute known as the "P-Multicast
   Service Interface Tunnel (PMSI
   Tunnel) attribute".  This (PMSI) Tunnel" attribute.  The attribute contains an octet a
   one-octet "Flags" field.  The purpose of "flags".
   Only one flag is defined in that RFC, but there this document is now a need to
   define additional flags.  Since the RFC did not create a
   establish an IANA registry for the assignment of flag bits, the bits in this document updates
   field.  Since the RFC by
   creating a registry for that purpose.  This Flags field contains only eight bits, this document
   also defines a new BGP Extended Community, "Additional PMSI Tunnel
   Attribute Flags", that can be used to carry additional flags for the
   PMSI Tunnel attribute.  This document updates RFC 6514.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
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   This Internet-Draft will expire on February 7, August 5, 2016.

Copyright Notice

   Copyright (c) 2015 2016 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

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Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Extending the PMSI Tunnel Attribute Flags Field . . . . . . .   2
   3.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   3
   4.  Security Considerations  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .   4
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .   5
   6.  Normative References  . . . . . . . . . . . . . . . . . . . .   4   5
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   4   5

1.  Introduction

   [RFC6514] defines

   A BGP attribute known as the "P-Multicast Service Interface Tunnel (PMSI
   Tunnel) attribute". (PMSI)
   Tunnel" attribute is defined in [RFC6514].  This attribute contains an octet a
   one-octet of "flags". "Flags" field.  Only one flag is defined in that RFC,
   but there is now a need to define additional flags.  Since the  However, that
   RFC did not create a an IANA registry for the assignment of flag bits, this bits in the
   Flags field.  This document creates a registry for that purpose.  In
   addition, there may be a need to define more than eight flags.
   Therefore this document defines a new BGP Extended Community,
   "Additional PMSI Tunnel Attribute Flags", that can be used to carry
   additional flags for the PMSI Tunnel attribute.  A registry is also
   created for this extended community, Extended Community, allowing IANA to
   allocate assign bits
   from the extended community's Extended Community's six-octet value field.

   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 [RFC2119].

2.  Extending the PMSI Tunnel Attribute Flags Field

   [RFC6514] defines

   In [RFC6514], only a single octet in the PMSI Tunnel attribute is
   defined to
   use for carry bit flags.  This allows eight flags, which is
   unlikely to be sufficient for all future applications.

   This document defines a new Transitive Opaque Extended Community,
   "Additional PMSI Tunnel Attribute Flags".  It also defines a new bit
   flag in the PMSI Tunnel Attribute flags field, called the "Extension"
   flag.

   The "Additional Additional PMSI Tunnel Attribute Flags" Flags Extended Community MUST
   NOT be added to carried by a given BGP UPDATE message unless that the following
   conditions both hold:

   o  the given BGP UPDATE message is also carrying a PMSI Tunnel attribute.  Further, when an "Additional PMSI
   Tunnel Attribute Flags" Extended Community is added to a BGP UPDATE
   message,
      attribute, and

   o  the "Extension" Extension flag of the that PMSI Tunnel attribute flags attribute's Flags field MUST be is
      set.

   If at any time the "Additional a given BGP UPDATE message is carrying a PMSI Tunnel attribute,
   but is not carrying an Additional PMSI Tunnel Attribute Flags" Flags
   Extended Community is removed from the UPDATE
   message, Community, then the "Extension" Extension flag in the PMSI Tunnel
   attribute MUST be
   cleared. clear.

   If a BGP speaker receives an UPDATE message that contains an
   "Additional
   Additional PMSI Tunnel Attribute Flags" Flags Extended Community, but either
   (a) that UPDATE message does not contain a PMSI Tunnel attribute, or
   (b) the
   "Extension" Extension flag of the PMSI Tunnel attribute is not set, then
   the Extended Community SHOULD be removed and SHOULD NOT be
   redistributed.  The BGP UPDATE message MUST be processed (and if
   necessary, redistributed) as if the Extended Community had not been
   present.

   If

   Suppose a BGP speaker receives an UPDATE message that contains a PMSI
   Tunnel attribute and attribute, but does not contain an "Additional Additional PMSI Tunnel
   Attribute Flags" Flags Extended Community, but Community.  If the Extension flag of the
   PMSI Tunnel attribute is set, then the "treat-as-withdraw" procedure
   of
   [ERRORS] [RFC7606] MUST be applied.

3.  IANA Considerations

   IANA is requested to create a new registry called "P-Multicast
   Service Interface (PMSI) Tunnel (PMSI Tunnel) Attribute Flags" in the "Border
   Gateway Protocol (BGP) Parameters" registry.

   Per [RFC6514] section 5, a PMSI Tunnel Attribute contains a "Flags"
   octet.  The Flags field is a single octet, with bits numbered, left-
   to-right, from 0 to 7.  IANA is requested to initialize the registry
   as follows:

       Bit Position      Description                      Reference
       (left to right)
            0            unassigned
            1            Extension                        This document
            2            unassigned
            3            unassigned
            4            unassigned
            5            unassigned
            6            unassigned
            7            Leaf Information Required (LIR) (L)    RFC6514

                        PMSI Tunnel Attribute Flags

   The registration procedure for this registry is Standards Action.

   IANA is also requested to assign a codepoint codepoint, from the "Transitive "First Come,
   First Served" range of the Transitive Opaque Extended Community Sub-Types" registry Sub-
   Types registry, for "Additional PMSI Tunnel Attribute Flags".
   [TO BE REMOVED: This registration should take place at the following
   location: http://www.iana.org/assignments/bgp-extended-communities
   /bgp-extended-communities.xhtml#trans-opaque]

   IANA is further requested to establish a registry for the bit flags
   carried in the Additional PMSI Tunnel Attribute Flags extended
   community.  The bits shall be numbered 0-47, with 0 being the most
   significant bit and 47 being the least significant bit.  The
   registration policy for this registry shall be "Standards Action".
   Initially, bits 0-47 are unassigned.  This
   [TO BE REMOVED: The creation of the registry belongs with should take place at the
   BGP Extended Communities registries.
   following location: http://www.iana.org/assignments/bgp-extended-
   communities/bgp-extended-communities.xhtml]
   The initial registry should be as follows:

       Bit Flag          Name          Reference

        0-47            unassigned

                  Additional PMSI Tunnel Attribute Flags

4.  Acknowledgments

   The authors wish to thank Martin Vigoureux for his review of this
   document.

5.  Security Considerations

   No

   This document establishes an IANA registry, and defines a new
   transitive opaque Extended Community.

   Establishment of an IANA registry does not raise any security
   considerations.

   While the document defines a new Extended Community for carrying bit
   flags, it does not define any of the bit flags in that Extended
   Community.  Therefore no security considerations are raised by this document.

5. raised.

6.  Normative References

   [ERRORS]   Chen, E., Scudder, J., Mohapatra, P., and K. Patel,
              "Revised Error Handling for BGP UPDATE Messages",
              internet-draft draft-ietf-idr-error-handling-19, April
              2015.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <http://www.rfc-editor.org/info/rfc2119>.

   [RFC6514]  Aggarwal, R., Rosen, E., Morin, T., and Y. Rekhter, "BGP
              Encodings and Procedures for Multicast in MPLS/BGP IP
              VPNs", RFC 6514, DOI 10.17487/RFC6514, February 2012,
              <http://www.rfc-editor.org/info/rfc6514>.

   [RFC7606]  Chen, E., Ed., Scudder, J., Ed., Mohapatra, P., and K.
              Patel, "Revised Error Handling for BGP UPDATE Messages",
              RFC 7606, DOI 10.17487/RFC7606, August 2015,
              <http://www.rfc-editor.org/info/rfc7606>.

Authors' Addresses

   Eric C. Rosen
   Juniper Networks, Inc.
   10 Technology Park Drive
   Westford, Massachusetts  01886
   United States

   Email: erosen@juniper.net

   Thomas Morin
   Orange
   2, avenue Pierre-Marzin
   22307 Lannion Cedex
   France

   Email: thomas.morin@orange.com