path: root/doc/rfc/rfc3085.txt

Network Working Group                                          A. Coates
Request for Comments: 3085                                       Reuters
Category: Informational                                         D. Allen
                                                                    IPTC
                                                         D. Rivers-Moore
                                                                  Rivcom
                                                              March 2001


                   URN Namespace for NewsML Resources

Status of this Memo

   This memo provides information for the Internet community.  It does
   not specify an Internet standard of any kind.  Distribution of this
   memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (2001).  All Rights Reserved.

Abstract

   This document describes a URN (Uniform Resource Name) namespace for
   identifying NewsML NewsItems.  A NewsItem is an information resource
   that is expressible as a NewsML element within a NewsML document
   conforming to the NewsML Document Type Declaration (DTD) as defined
   by the International Press Telecommunications Council (IPTC).

1. Introduction

   NewsML is an XML format for packaging multimedia news resources.  It
   has been created under the auspices of the International Press
   Telecommunications Council (IPTC), and version 1.0 was approved by
   the IPTC on 6 October 2000.

   The same logical NewsItem may exist in multiple physical locations.
   The NewsML specification allows NewsItems to have multiple URLs, but
   only a single URN.  It is the latter which then uniquely names the
   resource.

   This namespace specification is for a formal namespace.

2. Specification Template

   Namespace ID:

      "newsml" requested.



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   Registration Information:

      Registration Version Number: 1
      Registration Date: 2000-11-07

   Declared registrant of the namespace:

      David Allen
      ho73@dial.pipex.com
      IPTC
      Royal Albert House
      Sheet Street
      Windsor
      SL4 1BE

   Declaration of structure:

      The identifier has the following ABNF[6] specification:

      NSS = ProviderId ":" DateId ":" NewsItemId ":" RevisionId Update
      ProviderId = string
      DateId = date
      NewsItemId = string
      RevisionId = posint
      Update = 0*1( "A" / "U" )
      date = century year month day
      century = ( "0" posdig ) / ( posdig DIGIT )
      year = 1*2DIGIT
      month = ( 0 posdig ) / ( "1" ( "0" "1" "2" ) )
      day = ( 0 posdig ) / ( ( "1" / "2" ) DIGIT ) / "30" / "31"
      string = 1*char
      char = ALPHA / DIGIT / symbol / escape
      symbol = "(" / ")" / "+" / "," / "-" / "." / "=" / "@" / ";" /
        "$" / "_" / "!" / "*" / "'"
      escape = "%" HEXDIG HEXDIG
      posint = posdig *DIGIT
      posdig = "1" / "2" / "3" / "4" / "5" / "6" / "7" / "8" / "9"

      The ProviderId must be an Internet domain name, and must be owned
         by the organisation creating the NewsML resource and allocating
         the URN to it, at the date identified by the DateId.
      DateId is a date in ISO 8601 Basic Format (CCYYMMDD), and must
         correspond to a date at which the organisation allocating the
         URN owned the domain name specified in the ProviderId.
      The NewsItemId must be unique among all NewsItems emanating from
         the same provider and having the same DateId.





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      RevisionId is a positive integer indicating which revision of a
         given NewsItem this is.  Any positive integer may be used, but
         it must always be the case that of two instances of a NewsItem
         that have the same ProviderId, DateId and NewsItemId, the one
         whose RevisionId has the larger value must be the more recent
         revision.  A RevisionId of 0 is not permitted.
      If the NewsItem contains an "Update" element or elements, then
         Update must be set to "U".  If the NewsItem consists only of a
         replacement set of NewsManagement data, then Update must be set
         to "A".  If neither of these is the case, then Update must be
         suppressed.

   Relevant ancillary documentation:

      None

   Identifier uniqueness considerations:

      The combination of ProviderId and DateId serves to uniquely
         identify the organisation that is allocating the URN.  That
         organisation is responsible for ensuring the uniqueness of the
         DateId/NewsItemId/RevisionId combination.

   Identifier persistence considerations:

      A NewsML URN may only be allocated by an organisation that owns an
         Internet domain name.  The URN identifies a date on which the
         organisation owned that domain name.  The combination of date
         and domain name will serve to uniquely identify that
         organisation for all time.

   Process of identifier assignment:

      The organisation identified by the ProviderId/DateId combination
         is responsible for allocating a NewsItemId that is unique among
         all those that it allocates with that DateId.

   Process of identifier resolution:

      NewsML providers are responsible for the provision of a URN
         resolution service, if any, for NewsML URNs they have assigned
         with a valid ProviderId/DateId combination.

   Rules for Lexical Equivalence:

      URNs are lexically equivalent if the ProviderId, DateId,
         NewsItemId, and RevisionId are all identical (case-insensitive
         comparison).



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   Conformance with URN Syntax:

      No special considerations beyond the syntax herein described.

   Validation mechanism:

      Organisations that allocate NewsML URNs are responsible for the
         provision of a URN validation service, if any, for URNs they
         have assigned with a valid ProviderId/DateId combination.

   Scope:

      Global

3. Examples

   The following examples are representative of NewsML URNs, but may not
   refer to actual resources.

   urn:newsml:iptc.org:20001006:NewsMLv1.0:1
   urn:newsml:reuters.com:20000206:
              IIMFFH05643_2000-02-06_17-54-01_L06156584:1U

4. Security Considerations

   There are no additional security considerations other than those
   normally associated with the use and resolution of URNs in general.

References

   [1]  Rivers-Moore, D., "NewsML Version 1.0 Functional Specification",
        November 2000,
        <http://www.iptc.org/NewsML/specification/NewsMLv1.0.pdf>.

   [2]  Rivers-Moore, D., "NewsML Version 1.0 DTD", November 2000,
        <http://www.iptc.org/NewsML/DTD/NewsMLv1.0.dtd>.

   [3]  W3C, XML WG, "Extensible Markup Language (XML) 1.0", February
        1998, <http://www.w3.org/TR/REC-xml>.

   [4]  Moats, R., "URN Syntax", RFC 2141, May 1997.

   [5]  Daigle, L., van Gulik, D., Iannella, R. and P. Faltstrom, "URN
        Namespace Definition Mechanisms", RFC 2611, June 1999.

   [6]  Crocker, D. and P. Overell, "Augmented BNF for Syntax
        Specifications: ABNF", RFC 2234, November 1997.




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Authors' Addresses

   Anthony B. Coates
   Reuters
   85 Fleet St
   London  EC4P 4AJ
   United Kingdom

   Phone: +44 20 75 42 21 65
   EMail: tony.coates@reuters.com


   David Allen
   IPTC
   Royal Albert House
   Sheet Street
   Windsor  SL4 1BE
   United Kingdom

   Phone: +44 17 53 70 50 51
   EMail: ho73@dial.pipex.com


   Daniel Rivers-Moore
   Rivcom
   Lotmead Business Village
   Swindon  SN4 0UY
   United Kingdom

   Phone: +44 17 93 79 20 00
   EMail: daniel.rivers-moore@rivcom.com




















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Full Copyright Statement

   Copyright (C) The Internet Society (2001).  All Rights Reserved.

   This document and translations of it may be copied and furnished to
   others, and derivative works that comment on or otherwise explain it
   or assist in its implementation may be prepared, copied, published
   and distributed, in whole or in part, without restriction of any
   kind, provided that the above copyright notice and this paragraph are
   included on all such copies and derivative works.  However, this
   document itself may not be modified in any way, such as by removing
   the copyright notice or references to the Internet Society or other
   Internet organizations, except as needed for the purpose of
   developing Internet standards in which case the procedures for
   copyrights defined in the Internet Standards process must be
   followed, or as required to translate it into languages other than
   English.

   The limited permissions granted above are perpetual and will not be
   revoked by the Internet Society or its successors or assigns.

   This document and the information contained herein is provided on an
   "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
   TASK FORCE DISCLAIMS 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.

Acknowledgement

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



















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