[Docs] [txt|pdf|xml|html] [Tracker] [WG] [Email] [Diff1] [Diff2] [Nits]

Versions: (draft-dhody-pce-pcep-exp-codepoints) 00 01 02 03 04 05 RFC 8356

PCE Working Group                                               D. Dhody
Internet-Draft                                       Huawei Technologies
Updates: 5440 (if approved)                                      D. King
Intended status: Standards Track                    Lancaster University
Expires: July 14, 2018                                         A. Farrel
                                                        Juniper Networks
                                                        January 10, 2018


   Experimental Codepoint Allocation for the Path Computation Element
                     communication Protocol (PCEP)
                 draft-ietf-pce-pcep-exp-codepoints-05

Abstract

   IANA assigns values to the Path Computation Element (PCE)
   communication Protocol (PCEP) parameters (messages, objects, TLVs).
   IANA established a top-level registry to contain all PCEP codepoints
   and sub-registries.  This top-level registry contains sub-registries
   for PCEP message, object and TLV types.  The allocation policy for
   each of these sub-registries is IETF Review.

   This document updates RFC 5440 by changing the allocation policies
   for these three registries to mark some of the code points as
   assigned for Experimental Use.

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
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on July 14, 2018.

Copyright Notice

   Copyright (c) 2018 IETF Trust and the persons identified as the
   document authors.  All rights reserved.




Dhody, et al.             Expires July 14, 2018                 [Page 1]


Internet-Draft                EXP-CODEPOINT                 January 2018


   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 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.

   This document may contain material from IETF Documents or IETF
   Contributions published or made publicly available before November
   10, 2008.  The person(s) controlling the copyright in some of this
   material may not have granted the IETF Trust the right to allow
   modifications of such material outside the IETF Standards Process.
   Without obtaining an adequate license from the person(s) controlling
   the copyright in such materials, this document may not be modified
   outside the IETF Standards Process, and derivative works of it may
   not be created outside the IETF Standards Process, except to format
   it for publication as an RFC or to translate it into languages other
   than English.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  PCEP Messages . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  PCEP Objects  . . . . . . . . . . . . . . . . . . . . . . . .   3
   4.  PCEP TLVs . . . . . . . . . . . . . . . . . . . . . . . . . .   4
   5.  Handling of Unknown Experimentation . . . . . . . . . . . . .   4
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   4
     6.1.  New PCEP Messages . . . . . . . . . . . . . . . . . . . .   4
     6.2.  New PCEP Objects  . . . . . . . . . . . . . . . . . . . .   4
     6.3.  New PCEP TLVs . . . . . . . . . . . . . . . . . . . . . .   5
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .   5
   8.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .   5
   9.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   6
     9.1.  Normative References  . . . . . . . . . . . . . . . . . .   6
     9.2.  Informative References  . . . . . . . . . . . . . . . . .   6
   Appendix A.  Other PCEP Registries  . . . . . . . . . . . . . . .   8
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .   8

1.  Introduction

   The Path Computation Element communication Protocol (PCEP) [RFC5440]
   provides mechanisms for Path Computation Elements (PCEs) to perform
   path computations in response to Path Computation Clients (PCCs)
   requests.




Dhody, et al.             Expires July 14, 2018                 [Page 2]


Internet-Draft                EXP-CODEPOINT                 January 2018


   Further, in order to support use cases described in [RFC8051],
   [RFC8231] specifies a set of extensions to PCEP to enable stateful
   control of MPLS-TE and GMPLS LSPs via PCEP.  [RFC8281] describes the
   setup, maintenance and teardown of PCE-initiated LSPs under the
   stateful PCE model.

   In section 9 of [RFC5440], IANA assigns values to the PCEP protocol
   parameters (messages, objects, TLVs).  IANA established a top- level
   registry to contain all PCEP codepoints and sub-registries.  This
   top-level registry contains sub-registries for PCEP message, object
   and TLV types.  The allocation policy for each of these sub-
   registries is IETF Review [RFC8126].  Also, early allocation
   [RFC7120] provides some latitude for allocation of these code points,
   but is reserved for features that are considered appropriately
   stable.

   Recently, there have been rapid advancements in PCE technology, which
   has created an enhanced need to experiment with PCEP.  It is often
   necessary to use some sort of number or constant in order to actually
   test or experiment with the new function, even when testing in a
   closed environment.  In order to run experiments, it is important
   that the value won't collide not only with existing codepoints but
   any future allocation.

   This document updates [RFC5440] by changing the allocation policies
   for these three registries to mark some of the code points as
   assigned for Experimental Use.  As stated in [RFC3692], experiments
   using these code points are not intended to be used in general
   deployments and due care must be taken to ensure that two experiments
   with the same code points are not run in the same environment.  See
   [RFC3692] for further discussion of the use of experimental
   codepoints.

2.  PCEP Messages

   PCEP message types are in the range 0 to 255.  This document sets
   aside message types 252-255 for experimentation as described in
   Section 6.1.

3.  PCEP Objects

   PCEP objects are identified by values in the range 0 to 255.  This
   document sets aside object identifiers 248-255 for experimentation as
   described in Section 6.2.







Dhody, et al.             Expires July 14, 2018                 [Page 3]


Internet-Draft                EXP-CODEPOINT                 January 2018


4.  PCEP TLVs

   PCEP TLV type codes are in the range 0 to 65535.  This document sets
   aside object identifiers 65504-65535 for experimentation as described
   in Section 6.2.

5.  Handling of Unknown Experimentation

   A PCEP implementation that receives an experimental PCEP message,
   that it does not recognize, would react as per section 6.9 of
   [RFC5440] by sending a PCErr message with Error-value=2 (capability
   not supported).

   If a PCEP speaker does not understand or support an experimental
   object then the way it handles this situation depends on the message
   type.  For example, a PCE handles an unknown object in the Path
   Computation Request (PCReq) message according to the rules of
   [RFC5440].  Message-specific behavior may be specified (e.g.,
   [RFC8231] defines rules for a PCC to handle an unknown object in a
   Path Computation LSP Update (PCUpd) Request message).

   As per section 7.1 of [RFC5440], unknown experimental PCEP TLV would
   be ignored.

6.  IANA Considerations

   IANA maintains the "Path Computation Element Protocol (PCEP) Numbers"
   at <http://www.iana.org/assignments/pcep>.

6.1.  New PCEP Messages

   Within this registry IANA maintains a sub-registry for PCEP Messages
   (see PCEP Messages at <http://www.iana.org/assignments/pcep>).

   IANA is requested to change the registration procedure for this
   registry to read as follows:

      0-251   IETF Review
      252-255 Experimental Use

   IANA is also requested to mark the values 252-255 in the registry
   accordingly.

6.2.  New PCEP Objects

   Within this registry IANA maintains a sub-registry for PCEP Objects
   (see PCEP Objects at <http://www.iana.org/assignments/pcep>).




Dhody, et al.             Expires July 14, 2018                 [Page 4]


Internet-Draft                EXP-CODEPOINT                 January 2018


   IANA is requested to change the registration procedure for this
   registry to read as follows:

      0-247   IETF Review
      248-255 Experimental Use

   IANA is also requested to mark the values 248-255 in the registry
   accordingly.

6.3.  New PCEP TLVs

   Within this registry IANA maintains a sub-registry for PCEP TLVs (see
   PCEP TLV Type Indicators at <http://www.iana.org/assignments/pcep>).

   IANA is requested to change the registration procedure for this
   registry to read as follows:

      0-65503     IETF Review
      65504-65535 Experimental Use

   IANA is also requested to mark the values 65504-65535 in the registry
   accordingly.

7.  Security Considerations

   This document does not introduce any new security considerations to
   the existing protocol.  Refer to [RFC5440] for further details of the
   specific security measures.

   [RFC3692] asserts that the existence of experimental code points
   introduce no new security considerations.  However, implementations
   accepting experimental codepoints need to take care in how they parse
   and process the messages, objects, and TLVs in case they come,
   accidentally, from another experiment.  Further, an implementation
   accepting experimental code points needs to consider the security
   aspects of the experimental extensions.  [RFC6709] provide various
   design considerations for protocol extensions (including those
   designated as experimental).

8.  Acknowledgments

   The authors would like to thank Ramon Casellas, Jeff Tantsura, Julien
   Meuric, Lou Berger, Michael Shroff, and Andrew Dolganow for their
   feedback and suggestions.

   We would like to thank Jonathan Hardwick for shepherding this
   document and providing comments with text suggestions.




Dhody, et al.             Expires July 14, 2018                 [Page 5]


Internet-Draft                EXP-CODEPOINT                 January 2018


   Thanks Brian Carpenter for the GENART review.  Thanks Ben Niven-
   Jenkins and Scott Bradner for RTGDIR and OPSDIR reviews respectively.

9.  References

9.1.  Normative References

   [RFC3692]  Narten, T., "Assigning Experimental and Testing Numbers
              Considered Useful", BCP 82, RFC 3692,
              DOI 10.17487/RFC3692, January 2004,
              <https://www.rfc-editor.org/info/rfc3692>.

   [RFC5440]  Vasseur, JP., Ed. and JL. Le Roux, Ed., "Path Computation
              Element (PCE) Communication Protocol (PCEP)", RFC 5440,
              DOI 10.17487/RFC5440, March 2009,
              <https://www.rfc-editor.org/info/rfc5440>.

   [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>.

   [RFC8231]  Crabbe, E., Minei, I., Medved, J., and R. Varga, "Path
              Computation Element Communication Protocol (PCEP)
              Extensions for Stateful PCE", RFC 8231,
              DOI 10.17487/RFC8231, September 2017,
              <https://www.rfc-editor.org/info/rfc8231>.

   [RFC8281]  Crabbe, E., Minei, I., Sivabalan, S., and R. Varga, "Path
              Computation Element Communication Protocol (PCEP)
              Extensions for PCE-Initiated LSP Setup in a Stateful PCE
              Model", RFC 8281, DOI 10.17487/RFC8281, December 2017,
              <https://www.rfc-editor.org/info/rfc8281>.

9.2.  Informative References

   [RFC6709]  Carpenter, B., Aboba, B., Ed., and S. Cheshire, "Design
              Considerations for Protocol Extensions", RFC 6709,
              DOI 10.17487/RFC6709, September 2012,
              <https://www.rfc-editor.org/info/rfc6709>.

   [RFC7120]  Cotton, M., "Early IANA Allocation of Standards Track Code
              Points", BCP 100, RFC 7120, DOI 10.17487/RFC7120, January
              2014, <https://www.rfc-editor.org/info/rfc7120>.







Dhody, et al.             Expires July 14, 2018                 [Page 6]


Internet-Draft                EXP-CODEPOINT                 January 2018


   [RFC8051]  Zhang, X., Ed. and I. Minei, Ed., "Applicability of a
              Stateful Path Computation Element (PCE)", RFC 8051,
              DOI 10.17487/RFC8051, January 2017,
              <https://www.rfc-editor.org/info/rfc8051>.















































Dhody, et al.             Expires July 14, 2018                 [Page 7]


Internet-Draft                EXP-CODEPOINT                 January 2018


Appendix A.  Other PCEP Registries

   Based on feedback from the PCE WG, it was decided to allocate an
   Experimental code point range only in the message, object and TLV
   sub-registries.  The justification for this decision is that, if an
   experiment finds that it wants to use a new code point in another
   PCEP sub-registry, it can implement the same function using a new
   experimental object or TLV instead.

Authors' Addresses

   Dhruv Dhody
   Huawei Technologies
   Divyashree Techno Park, Whitefield
   Bangalore, Karnataka  560066
   India

   EMail: dhruv.ietf@gmail.com


   Daniel King
   Lancaster University
   UK

   EMail: d.king@lancaster.ac.uk


   Adrian Farrel
   Juniper Networks
   UK

   EMail: afarrel@juniper.net



















Dhody, et al.             Expires July 14, 2018                 [Page 8]


Html markup produced by rfcmarkup 1.126, available from https://tools.ietf.org/tools/rfcmarkup/