Internet Engineering Task Force (IETF)                      M. Boucadair
Request for Comments: 9304                                  C. Jacquenet
Obsoletes: 8113                                                   Orange
Category: Standards Track                                   October 2022
ISSN: 2070-1721


Locator/ID Separation Protocol (LISP): Shared Extension Message and IANA
                 Registry for Packet Type Allocations

Abstract

  This document specifies a Locator/ID Separation Protocol (LISP)
  shared message type for defining future extensions and conducting
  experiments without consuming a LISP Packet Type codepoint for each
  extension.

  This document obsoletes RFC 8113.

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 7841.

  Information about the current status of this document, any errata,
  and how to provide feedback on it may be obtained at
  https://www.rfc-editor.org/info/rfc9304.

Copyright Notice

  Copyright (c) 2022 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
  (https://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 Revised BSD License text as described in Section 4.e of the
  Trust Legal Provisions and are provided without warranty as described
  in the Revised BSD License.

Table of Contents

  1.  Introduction
  2.  Requirements Language
  3.  LISP Shared Extension Message Type
  4.  Security Considerations
  5.  IANA Considerations
    5.1.  LISP Packet Types
    5.2.  Sub-Types
  6.  Changes from RFC 8113
  7.  Normative References
  Acknowledgments
  Authors' Addresses

1.  Introduction

  The Locator/ID Separation Protocol (LISP) base specification,
  [RFC9301], defines a set of primitives that are identified with a
  packet type code.  Several extensions have been proposed to add more
  LISP functionalities.  It is expected that additional LISP extensions
  will be proposed in the future.

  The "LISP Packet Types" IANA registry (see Section 5) is used to ease
  the tracking of LISP message types.

  Because of the limited type space [RFC9301] and the need to conduct
  experiments to assess new LISP extensions, this document specifies a
  shared LISP extension message type and describes a procedure for
  registering LISP shared extension sub-types (see Section 3).
  Concretely, one single LISP message type code is dedicated to future
  LISP extensions; sub-types are used to uniquely identify a given LISP
  extension making use of the shared LISP extension message type.
  These identifiers are selected by the author(s) of the corresponding
  LISP specification that introduces a new LISP extension message type.

2.  Requirements Language

  The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
  "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
  "OPTIONAL" in this document are to be interpreted as described in
  BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
  capitals, as shown here.

3.  LISP Shared Extension Message Type

  Figure 1 depicts the common format of the LISP shared extension
  message.  The type field MUST be set to 15 (see Section 5).

     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
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    |Type=15|        Sub-type       |   extension-specific          |
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
    //                    extension-specific                       //
    //                                                             //
    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

               Figure 1: LISP Shared Extension Message Type

  The 'Sub-type' field conveys a unique identifier that MUST be
  registered with IANA (see Section 5.2).

  The exact structure of the 'extension-specific' portion of the
  message is specified in the corresponding specification document.

4.  Security Considerations

  This document does not introduce any additional security issues other
  than those discussed in [RFC9301].

5.  IANA Considerations

5.1.  LISP Packet Types

  IANA has created a registry titled "LISP Packet Types", numbered
  0-15.

  Values can be assigned via Standards Action [RFC8126].  Documents
  that request for a new LISP Packet Type may indicate a preferred
  value in the corresponding IANA sections.

  IANA has replaced the reference to RFC 8113 with the RFC number of
  this document.

  Also, IANA has updated the table as follows:

  OLD:

  +===============================+======+===========+
  | Message                       | Code | Reference |
  +===============================+======+===========+
  | LISP Shared Extension Message | 15   | [RFC8113] |
  +-------------------------------+------+-----------+

                        Table 1

  NEW:

  +===============================+======+===========+
  | Message                       | Code | Reference |
  +===============================+======+===========+
  | LISP Shared Extension Message | 15   | RFC 9304  |
  +-------------------------------+------+-----------+

                        Table 2

5.2.  Sub-Types

  IANA has created the "LISP Shared Extension Message Type Sub-types"
  registry.  IANA has updated that registry by replacing the reference
  to RFC 8113 with the RFC number of this document.

  The values in the range 0-1023 are assigned via Standards Action.
  This range is provisioned to anticipate, in particular, the
  exhaustion of the LISP Packet Types.

  The values in the range 1024-4095 are assigned on a First Come, First
  Served (FCFS) basis.  The registration procedure is to provide IANA
  with the desired codepoint and a point of contact; providing a short
  description (together with an acronym, if relevant) of the foreseen
  usage of the extension message is also encouraged.

6.  Changes from RFC 8113

  The following changes were made from RFC 8113:

  *  Changed the status from Experimental to Standards Track.

  *  Indicated explicitly that the shared extension is used for two
     purposes: extend the type space and conduct experiments to assess
     new LISP extensions.

  *  Deleted pointers to some examples illustrating how the shared
     extension message is used to extend the LISP protocol.

  *  IANA has updated the "IANA LISP Packet Types" and "LISP Shared
     Extension Message Type Sub-types" registries to point to this
     document instead of RFC 8113.

7.  Normative References

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

  [RFC8126]  Cotton, M., Leiba, B., and T. Narten, "Guidelines for
             Writing an IANA Considerations Section in RFCs", BCP 26,
             RFC 8126, DOI 10.17487/RFC8126, June 2017,
             <https://www.rfc-editor.org/info/rfc8126>.

  [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
             2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
             May 2017, <https://www.rfc-editor.org/info/rfc8174>.

  [RFC9301]  Farinacci, D., Maino, F., Fuller, V., and A. Cabellos,
             Ed., "Locator/ID Separation Protocol (LISP) Control
             Plane", RFC 9301, DOI 10.17487/RFC9301, October 2022,
             <https://www.rfc-editor.org/info/rfc9301>.

Acknowledgments

  This work is partly funded by ANR LISP-Lab project #ANR-13-INFR-
  009-X.

  Many thanks to Luigi Iannone, Dino Farinacci, and Alvaro Retana for
  the review.

  Thanks to Geoff Huston, Brian Carpenter, Barry Leiba, and Suresh
  Krishnan for the review.

Authors' Addresses

  Mohamed Boucadair
  Orange
  35000 Rennes
  France
  Email: [email protected]


  Christian Jacquenet
  Orange
  35000 Rennes
  France
  Email: [email protected]