A Uniform Resource Name (URN) Namespace for the International Press Telecommunications Council (IPTC)
draft-steidl-iptc-urn-00

URN Namespace for IPTC           November 2003 
 
 
Network Working Group                                                
Internet Draft                                                M. Steidl 
Document: draft-steidl-iptc-urn-00.txt                             IPTC 
Expires: May 2004                                         November 2003 
    
    
                 A Uniform Resource Name(URN)Namespace for  
         the International Press Telecommunications Council (IPTC) 
    
    
Status of this Memo 
   This document is an Internet-Draft and is in full conformance with 
   all provisions of Section 10 of RFC2026 [i].  
   Internet-Drafts are working documents of the Internet Engineering 
   Task Force (IETF), its areas, and its working groups.  Note that 
   other groups may also distribute working documents as Internet-
   Drafts. 
   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 ôwork in progress.ö 
   The list of current Internet-Drafts can be accessed at 
   http://www.ietf.org/ietf/1id-abstracts.txt 
   The list of Internet-Draft Shadow Directories can be accessed at 
   http://www.ietf.org/shadow.html. 
    
    
Abstract 
   This document describes a URN (Uniform Resource Name) namespace for 
   identifying persistent resources published by the International Press 
   Telecommunications Council, IPTC. These resources include XML Data 
   Type Definition files (DTD), XML Schema, Namespaces in XML, XSL 
   stylesheets, other XML based document and documents of other data 
   formats like PDF documents, Microsoft Office documents and others. 
    
    
Table of Contents 
   1. Introduction...................................................2 
   2. IANA URN Specification Template................................2 
      2.1 Namespace ID...............................................2 
      2.2 Registration Information...................................2 
      2.3 Declaration of syntactic structure.........................3 
      2.4 Relevant ancillary documentation...........................4 
      2.5 Identifier uniqueness considerations.......................4 
      2.6 Identifier persistence considerations......................4 
      2.7 Process of identifier assignment...........................5 
      2.8 Process for identifier resolution..........................5 
      2.9 Rules for Lexical Equivalence..............................5 
      2.10 Conformance with URN Syntax...............................5 
 
 
Steidl                    Expires - May 2004                  [Page 1] 

                        URN Namespace for IPTC           November 2003 
 
 
      2.11 Validation mechanism......................................5 
      2.12 Scope.....................................................5 
   3. Examples.......................................................5 
   4. Namespace Considerations and Community Considerations..........6 
   5. Security Considerations........................................7 
   6. IANA Considerations............................................7 
   References........................................................7 
   AuthorÆs Addresses................................................7 
    
    
1. Introduction 
    
   The International Press Telecommunications Council (IPTC) is a non-
   profit consortium of the world's major news agencies and news 
   industry vendors. It develops and maintains technical standards for 
   the news business that are used by virtually every major news 
   organization in the world. IPTC was established in 1965.
    
   Since the 1990's IPTC's standardization work is based on open 
   standards like first SGML, then the XML family of standards, MIME, 
   Unicode etc.  
    
   As some of these standards require identification of resources IPTC 
   was looking for a technology for globally unique, persistent and 
   location-independent identifiers and decided to implement URNs as 
   described in "URN Syntax" [RFC 2141] for this reason. 
    
   This namespace specification is for a formal namespace. 
    
    
2. IANA URN Specification Template 
    
    
2.1 Namespace ID 
    
       "iptc" requested. 
    
2.2 Registration Information 
    
       Registration Version Number: 1 
       Registration Date: 2003-11-11 
    
     Declared registrant of the namespace: 
    
       Registering organization: 
         International Press Telecommunications Council IPTC 
         Royal Albert House 
         Sheet Street 
         Windsor, Berkshire SL4 1BE 
 
 
Steidl                    Expires - May 2004                  [Page 2] 

                        URN Namespace for IPTC           November 2003 
 
 
         www.iptc.org 
    
       Designated contact person: 
         Michael Steidl 
         Managing Director 
         mdirector@iptc.org 
    
    
2.3 Declaration of syntactic structure 
    
   All URNs assigned by IPTC will have a Namespace Specific String (NSS) 
   of the following hierarchical structure: 
    
   At the top of the hierarchy are three branches: 
   - "std" 
   - "std-draft" 
   - "workdoc" 
    
    
   The "std" branch hierarchy: 
      
     The "std" branch URNs will be assigned to IPTC resources used for 
     specifying and explaining any aspect of an IPTC standard. 
      
     The NSS in the "std" branch will have this general structure: 
      
     urn:iptc:std:{std-name}:{std-version}:{res-group} 
         {:res-name}?{:res-version}? 
      
     where 
     "std-name" is a unique identifier for an IPTC standard. 
     "std-version" reflects the version of this standard. The value 
         'current' will be assigned to point at resources of the current  
         version of a standard. 
     "res-group": this field will take only three values:  
        "spec" for all resources specifying a standard,  
        "doc" for all resources used for additional documentation of  
           and to support the use of a standard. 
        "xmlns" for defining an XML namespace. 
     "res-name" is an identifier for a tangible resource; the name 
     should describe the content or the use of the resource. Since not 
     all resources are tangible this value is optional. 
     "res-version" reflects the version of this resource as long as it 
     takes a physical format û like e.g. a file. Since not all resources 
     are of a physical kind this value is optional. 
    
    
   The "std-draft" branch hierarchy: 
      
 
 
Steidl                    Expires - May 2004                  [Page 3] 

                        URN Namespace for IPTC           November 2003 
 
 
     The "std-draft" branch URNs will be assigned to IPTC resources used 
     for specifying and explaining any aspect of an IPTC standard while 
     being in draft status, that is at a time when the resource is not 
     formally approved by the IPTC Standards body. 
      
     The NSS in the "std" branch will have this general structure: 
      
     urn:iptc:std-draft:{std-name}:{std-version}:{res-group} 
         {:res-name}?{:res-version}? 
      
     The substructure of "urn:iptc:std-draft" is identical to that of 
     "urn:iptc:std", find all explanations there. 
      
      
   The "workdoc" branch hierarchy: 
      
     The "workdoc" branch URNs will be assigned to IPTC resources not 
     directly related to IPTC standards but to the work of IPTC. 
      
     The NSS in the "doc" branch will have this general structure: 
      
     urn:iptc:workdoc:{group-id}:{doc-id}:{doc-version}{:doc-descr}? 
         
      
     where 
     "group-id" is a unique identifier for working groups and working 
     areas of IPTC and constitutes a document group. 
     "doc-id" is a unique identifier for a document within a document 
     group. 
     "doc-version" reflects the version of this work document. 
     "doc-descr" is an optional concise description of the document 
     content. 
      
    
2.4 Relevant ancillary documentation 
    
   None 
    
    
2.5 Identifier uniqueness considerations 
    
   Identifier uniqueness will be enforced by the Managing Director of 
   IPTC who will assign unique identifiers to all resources identified 
   by a URN. 
    
    
2.6 Identifier persistence considerations 
    

                
 
Steidl                    Expires - May 2004                  [Page 4] 

                        URN Namespace for IPTC           November 2003 
 
 
   IPTC is committed to maintaining the accessibility and persistence of 
   all resources that are identified by an IPTC URN. 
    
    
2.7 Process of identifier assignment 
    
   Assignment is limited to the owner of this namespace and its 
   authorities.  
    
    
2.8 Process for identifier resolution 
    
   IPTC will develop an appropriate mechanism that maps all assigned 
   URNs to Uniform Resource Locators (URL), specifically to enable web 
   based resolution of URNs.  
    
    
2.9 Rules for Lexical Equivalence 
    
   No special considerations, the rules for lexical equivalence  
   of RFC 2141 apply. 
    
    
2.10 Conformance with URN Syntax 
    
   No special considerations. 
    
    
2.11 Validation mechanism 
    
   None specified. IPTC will develop a mechanism for resolving URNs to 
   URLs (see 2.8), this mechanism will also show whether a URN is valid. 
    
    
2.12 Scope 
    
   Global. 
    
    
3. Examples 
    
   The following examples are representative for IPTC URNs, but may not 
   refer to actual resources. 
    
   urn:iptc:std:NewsML:1.1:spec:DTD:1 
     DTD version 1 to specify the IPTC standard "NewsML", version 1.1 
    
   urn:iptc:std-draft:NITF:3.5:spec:xml-schema:2 
     Second draft XML Schema  for the IPTC standard "NITF", version 3.5 
 
 
Steidl                    Expires - May 2004                  [Page 5] 

                        URN Namespace for IPTC           November 2003 
 
 
    
   urn:iptc:std:SportsML:1.0:xmlns 
     URN to identify an XML namespace for the IPTC standard "SportsML", 
     version 1.0. No "res-name" and "res-version" since an XML namespace 
     is of no physical format. 
    
   urn:iptc:std:NewsML:1.1:doc:news-agency-guidelines:1.2 
     Supporting document named "news-agency-guidelines", version 1, 
     revision 2, based on the IPTC standard "NewsML" version 1.1. 
    
   urn:iptc:workdoc:NMA:0315:1:srs-terms 
     Work document of IPTC's News Metadata Working Party (NMA), version 
     1, holding terms of the Subject Reference System 
    
    
4. Namespace Considerations and Community Considerations 
    
   The IPTC acknowledged already the use of URNs during the development 
   of its XML based standard "NewsML". This standard implements the use 
   of URNs as unique identifiers for news items as described in "URN 
   Namespace for NewsML resources"[RFC3085]. 
    
   While developing additional XML based standards as siblings to 
   NewsML, IPTC soon got aware that URNs have to be assigned to 
   resources that fall beyond the scope of the NewsML namespace. For 
   this reason IPTC developed a new and very general hierarchical 
   namespace structure to cover the needs of the currently developed 
   standards as well as future standards and to be able to assign URNs 
   to resources emanating from them.  
    
   In addition to resources relating directly to its standards, IPTC 
   also produces and publishes other documents relevant to the news 
   business. As those resources are used by many organizations outside 
   the IPTC membership and therefore could not be considered as internal 
   documents IPTC decided to add a branch to the URN hierarchy to be 
   assigned to these resources. 
    
   IPTC maintains global activities and its standards as well as 
   resources based on them are used world wide. Since one focus of the 
   activities of IPTC is on global exchange of news any system for 
   unique identification of resources has to be considered under global 
   aspects.  
    
   For this reason IPTC considers the introduction of a URN namespace 
   for its resources as proper action to maintain globally unique, 
   persistent and location-independent identifiers based on open 
   standards. 
    
    
 
 
Steidl                    Expires - May 2004                  [Page 6] 

                        URN Namespace for IPTC           November 2003 
 
 
5. Security Considerations 
    
   There are no additional security considerations other than those 
   normally associated with the use and resolution of URNs in general. 
    
    
6. IANA Considerations 
    
   This document includes a URN Namespace registration that conforms to 
   the "Uniform Resources Names (URN) Namespace Definition Mechanism" 
   [RFC3406] and is to be entered into the IANA registry for URN NIDs. 
    
    
References 
    
   [RFC2141] Moats, R., "URN Syntax", RFC 2141, May 1997. 
    
   [RFC3406] Daigle, L. et al., "Uniform Resource Names (URN) 
       Namespace Definition Mechanisms", RFC 3406, October 2002. 
    
   [W3CXML] W3C, XML WG, "Extensible Markup Language (XML) 1.0",  
       February 1998, <http://www.w3.org/TR/REC-xml>. 
    
   [W3CXMLNS] W3C, Namespaces WG, "Namespaces in XML", January 1999, 
       <http://www.w3.org/TR/REC-xml-names>. 
    
   [RFC2483] Mealling, M. and R. Daniel, "URI Resolution Services  
       Necessary for URN Resolution", RFC 2483, January 1999. 
    
   [RFC3085] Coates, et al., "URN Namespace for NewsML resources", 
       RFC 3085, March 2001. 
    
    
AuthorÆs Addresses 
   Michael Steidl 
   IPTC (International Press Telecommunications Council) 
   Royal Albert House 
   Sheet Street 
   Windsor SL4 1BE 
   United Kingdom 
    
   Phone: +44 (1753) 705 051 
   Email: mdirector@iptc.org 
     
                     
    

                
 
Steidl                    Expires - May 2004                  [Page 7]