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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RFC 3762          ENUM Service Registration for H.323         April 2004


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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RFC 3762          ENUM Service Registration for H.323         April 2004


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:  oritl@microsoft.com










































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RFC 3762          ENUM Service Registration for H.323         April 2004


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
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   pertain to the implementation or use of the technology described in
   this document or the extent to which any license under such rights
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   made any independent effort to identify any such rights.  Information
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   The IETF invites any interested party to bring to its attention any
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Acknowledgement

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









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