Network Working Group                                           O. Levin
Request for Comments: 3762                         Microsoft Corporation
Category: Standards Track                                     April 2004


    Telephone Number Mapping (ENUM) Service Registration for H.323

Status of this Memo

  This document specifies an Internet standards track protocol for the
  Internet community, and requests discussion and suggestions for
  improvements.  Please refer to the current edition of the "Internet
  Official Protocol Standards" (STD 1) for the standardization state
  and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

  Copyright (C) The Internet Society (2004).  All Rights Reserved.

Abstract

  The H.323 specification defines a means for building multimedia
  communication services over an arbitrary Packet Based Network,
  including the Internet.  This document registers a Telephone Number
  Mapping (ENUM) service for H.323 according to specifications and
  guidelines in RFC 3761.

Table of Contents

  1.  Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . 2
  2.  ENUM Service Registration . . . . . . . . . . . . . . . . . . . 2
  3.  The E2U+H323 ENUM Service . . . . . . . . . . . . . . . . . . . 2
  4.  Conventions Used in this Document . . . . . . . . . . . . . . . 3
  5.  Security Considerations . . . . . . . . . . . . . . . . . . . . 3
  6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 3
  7.  References. . . . . . . . . . . . . . . . . . . . . . . . . . . 3
      7.1.  Normative References. . . . . . . . . . . . . . . . . . . 3
      7.2.  Informative References. . . . . . . . . . . . . . . . . . 3
  8.  Author's Address. . . . . . . . . . . . . . . . . . . . . . . . 4
  9.  Full Copyright Statement. . . . . . . . . . . . . . . . . . . . 5











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1.  Introduction

  The H.323 specification [2] defines a means for building multimedia
  communication services over an arbitrary Packet Based Network,
  including the Internet.  When H.323 is used in the context of the
  Internet, it would be useful to take advantages of such services as
  domain name system (DNS) and ENUM in order to help facilitate the
  completion of multimedia calls.

  This document registers an ENUM service for H.323 according to
  specifications and guidelines in RFC 3761 [3].

2.  ENUM Service Registration

  As defined in [3], the following is a template covering information
  needed for the registration of the enumservice specified in this
  document.

  -  Service Name: "E2U+H323"
  -  URI Scheme(s): "h323:"
  -  Functional Specification: see section "3. The E2U+H323 ENUM
     Service"
  -  Security considerations: see section "5. Security Considerations"
  -  Intended usage: COMMON
  -  Author: Orit Levin
  -  Any other information that the author deems interesting: None

3.  The E2U+H323 ENUM Service

  This document defines the "E2U+H323" service to be used in the
  "service" sub-field of the "enumservice" as defined in [3].

  The H.323 related ENUM record MUST be populated with a standard H.323
  URL as defined in [2].  This URL MAY include parameters specifying
  the specific protocols and the transport means the H.323 entity
  supports.

  The H.323 entity MUST fully comply with the procedures defined in [3]
  for both record retrieval and processing by the DNS client.

  If, as a result of the ENUM DNS lookup, an H.323 URL matching local
  policies and capabilities is retrieved, the procedure defined in
  section O.8.1 "Locating H.323 Destination" of [5] SHOULD be
  performed.







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4.  Conventions used in this document

  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 BCP 14, RFC 2119 [1].

5.  Security Considerations

  The h323-URL information, once populated in the DNS, effectively
  becomes publicly accessible.  The access to the H.323 destinations
  (published using ENUM) can be secured by techniques and procedures
  defined in H.235 [4] - the security framework for H.323.  The
  framework defines means for achieving integrity, authentication,
  non-repudiation, encryption, etc. for H.323 calls.  An analysis of
  threats specific to the dependence of ENUM on the DNS, and the
  applicability of DNSSEC [6] to these, is provided in [3].

6.  IANA Considerations

  This document registers the E2U+H323 ENUM service according to
  specifications and guidelines in RFC 3761 [3] and the definitions in
  this document.

7.  References

7.1.  Normative References

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

  [2]  "Packet-based multimedia communications systems", ITU-T
       Recommendation H.323, 2003.

  [3]  Faltstrom, P. and M. Mealling, "The E.164 to Uniform Resource
       Identifiers (URI) Dynamic Delegation Discovery System (DDDS)
       Application (ENUM)", RFC 3761, April 2004.

  [4]  "Security and encryption for H-Series(H.323 and other H.245-
       based) multimedia terminals", ITU-T Recommendation H.235, 2003.

  [5]  "Usage of URLs and DNS", ITU-T Recommendation H.323 Annex O,
       2003.

7.2.  Informative References

  [6]  R. Arends, et al., "Protocol Modifications for the DNS Security
       Extensions", Work in Progress, February 2004.




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8.  Author's Address

  Orit Levin
  Microsoft Corporation
  One Microsoft Way
  Redmond, WA 98052
  USA

  EMail:  [email protected]










































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9.  Full Copyright Statement

  Copyright (C) The Internet Society (2004).  This document is subject
  to the rights, licenses and restrictions contained in BCP 78, and
  except as set forth therein, the authors retain all their rights.

  This document and the information contained herein are provided on an
  "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
  OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
  ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
  INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
  INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
  WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Intellectual Property

  The IETF takes no position regarding the validity or scope of any
  Intellectual Property Rights or other rights that might be claimed to
  pertain to the implementation or use of the technology described in
  this document or the extent to which any license under such rights
  might or might not be available; nor does it represent that it has
  made any independent effort to identify any such rights.  Information
  on the procedures with respect to rights in RFC documents can be
  found in BCP 78 and BCP 79.

  Copies of IPR disclosures made to the IETF Secretariat and any
  assurances of licenses to be made available, or the result of an
  attempt made to obtain a general license or permission for the use of
  such proprietary rights by implementers or users of this
  specification can be obtained from the IETF on-line IPR repository at
  http://www.ietf.org/ipr.

  The IETF invites any interested party to bring to its attention any
  copyrights, patents or patent applications, or other proprietary
  rights that may cover technology that may be required to implement
  this standard.  Please address the information to the IETF at ietf-
  [email protected].

Acknowledgement

  Funding for the RFC Editor function is currently provided by the
  Internet Society.









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