Internet Engineering Task Force (IETF)                     M. Westerlund
Request for Comments: 6336                                      Ericsson
Updates: 5245                                                 C. Perkins
Category: Standards Track                          University of Glasgow
ISSN: 2070-1721                                                July 2011


IANA Registry for Interactive Connectivity Establishment (ICE) Options

Abstract

  It has been identified that "Interactive Connectivity Establishment
  (ICE): A Protocol for Network Address Translator (NAT) Traversal for
  Offer/Answer Protocols" (RFC 5245) is missing a registry for ICE
  options.  This document defines this missing IANA registry and
  updates RFC 5245.

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/rfc6336.

Copyright Notice

  Copyright (c) 2011 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.






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Table of Contents

  1. Introduction ....................................................2
  2. Requirements Language ...........................................2
  3. IANA Considerations .............................................3
     3.1. ICE Options ................................................3
  4. Security Considerations .........................................3
  5. Acknowledgements ................................................4
  6. References ......................................................4
     6.1. Normative References .......................................4
     6.2. Informative References .....................................4

1.  Introduction

  "Interactive Connectivity Establishment (ICE): A Protocol for Network
  Address Translator (NAT) Traversal for Offer/Answer Protocols"
  [RFC5245] defines a concept of ICE options.  However, the ICE RFC
  fails to create an IANA registry for ICE options.  As one ICE option
  is under specification in [ECN-FOR-RTP], there is now a need to
  create the registry.

  RFC 5245 says: "ICE provides for extensibility by allowing an offer
  or answer to contain a series of tokens that identify the ICE
  extensions used by that agent.  If an agent supports an ICE
  extension, it MUST include the token defined for that extension in
  the ice-options attribute".

  Thus, as future extensions are defined, these ICE options need to be
  registered with IANA to ensure non-conflicting identification.  The
  ICE option identifiers are used in signalling between the ICE
  endpoints to negotiate extension support.  RFC 5245 defines one
  method of signalling these ICE options, using the Session Description
  Protocol (SDP) with Offer/Answer [RFC3264].

  This document updates the ICE specification [RFC5245] to define the
  "Interactive Connectivity Establishment (ICE) Options" registry.

2.  Requirements Language

  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 RFC 2119 [RFC2119].









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3.  IANA Considerations

  This document defines a registry "Interactive Connectivity
  Establishment (ICE) Options" for ICE options that can be used in the
  SDP "ice-options" attribute or other signalling parameters carrying
  the ICE options.

3.1.  ICE Options

  An ICE option identifier MUST fulfill the ABNF [RFC5234] syntax for
  "ice-option-tag" as specified in [RFC5245].  This syntax is
  reproduced here for simplicity, but the authoritative definition is
  in the ICE RFC:

  ice-option-tag        = 1*ice-char
  ice-char              = ALPHA / DIGIT / "+" / "/"

  ICE options are of unlimited length according to the syntax; however,
  they are RECOMMENDED to be no longer than 20 characters.  This is to
  reduce message sizes and allow for efficient parsing.

  Registration of an ICE option in the "Interactive Connectivity
  Establishment (ICE) Options" registry is done using the Specification
  Required policy as defined in "Guidelines for Writing an IANA
  Considerations Section in RFCs" [RFC5226].

  A registration request MUST include the following information:

  o  The ICE option identifier to be registered

  o  Name, Email, and Address of a contact person for the registration

  o  Organization or individuals having the change control

  o  Short description of the ICE extension to which the option relates

  o  Reference(s) to the specification defining the ICE option and the
     related extensions

  This document registers no ICE option.

4.  Security Considerations

  As this document defines an IANA registry for an already existing
  concept, there are no new security considerations.






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5.  Acknowledgements

  The authors would like to thank the people who reviewed the document
  and provided feedback: Flemming Andreasen, Mykyta Yevstifeyev, Amanda
  Baber, and Brian Carpenter.

6.  References

6.1.  Normative References

  [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
             Requirement Levels", BCP 14, RFC 2119, March 1997.

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

  [RFC5234]  Crocker, D., Ed., and P. Overell, "Augmented BNF for
             Syntax Specifications: ABNF", STD 68, RFC 5234,
             January 2008.

  [RFC5245]  Rosenberg, J., "Interactive Connectivity Establishment
             (ICE): A Protocol for Network Address Translator (NAT)
             Traversal for Offer/Answer Protocols", RFC 5245,
             April 2010.

6.2.  Informative References

  [ECN-FOR-RTP]
             Westerlund, M., Johansson, I., Perkins, C., O'Hanlon, P.,
             and K. Carlberg, "Explicit Congestion Notification (ECN)
             for RTP over UDP", Work in Progress, July 2011.

  [RFC3264]  Rosenberg, J. and H. Schulzrinne, "An Offer/Answer Model
             with Session Description Protocol (SDP)", RFC 3264,
             June 2002.















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Authors' Addresses

  Magnus Westerlund
  Ericsson
  Farogatan 6
  SE-164 80 Kista
  Sweden

  Phone: +46 10 714 82 87
  EMail: [email protected]


  Colin Perkins
  University of Glasgow
  School of Computing Science
  Glasgow  G12 8QQ
  United Kingdom

  EMail: [email protected]
































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