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

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

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

Abstract

   RFC6514 defines the "P-Multicast Service Interface Tunnel (PMSI
   Tunnel) attribute".  This attribute contains an octet of "flags".
   Only one flag is defined in that RFC, but there is now a need to
   define additional flags.  Since the RFC did not create a registry for
   the assignment of flag bits, this document updates the RFC by
   creating a registry for that purpose.  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.

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, 2016.

Copyright Notice

   Copyright (c) 2015 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

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   publication of this document.  Please review these documents
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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 . . . . . . . . . . . . . . . . . . .   4
   5.  Normative References  . . . . . . . . . . . . . . . . . . . .   4
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   4

1.  Introduction

   [RFC6514] defines the "P-Multicast Service Interface Tunnel (PMSI
   Tunnel) attribute".  This attribute contains an octet of "flags".
   Only one flag is defined in that RFC, but there is now a need to
   define additional flags.  Since the RFC did not create a registry for
   the assignment of flag bits, 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, allowing IANA to
   allocate bits from the 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 only a single octet in the PMSI Tunnel attribute to
   use for 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 PMSI Tunnel Attribute Flags" Extended Community MUST
   NOT be added to a BGP UPDATE message unless that message is also
   carrying a PMSI Tunnel attribute.  Further, when an "Additional PMSI

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   Tunnel Attribute Flags" Extended Community is added to a BGP UPDATE
   message, the "Extension" flag of the PMSI Tunnel attribute flags
   field MUST be set.  If at any time the "Additional PMSI Tunnel
   Attribute Flags" Extended Community is removed from the UPDATE
   message, the "Extension" flag in the PMSI Tunnel attribute MUST be
   cleared.

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

3.  IANA Considerations

   IANA is requested to create a new registry called "P-Multicast
   Service Interface 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)  RFC6514

                        PMSI Tunnel Attribute Flags

   The registration procedure for this registry is Standards Action.

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   IANA is also requested to assign a codepoint from the "Transitive
   Opaque Extended Community Sub-Types" registry for "Additional PMSI
   Tunnel Attribute Flags".

   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 registry belongs with the
   BGP Extended Communities registries.

4.  Security Considerations

   No security considerations are raised by this document.

5.  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>.

Authors' Addresses

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

   Email: erosen@juniper.net

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

   Email: thomas.morin@orange.com

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