Network Working Group M. Steidl Internet-Draft IPTC Intended status: Informational J. Lorenzen Obsoletes: 3085 Businesswire Expires: January 8, 2010 July 7, 2009 URN Namespace for news-related resources draft-steidl-newsml-urn-rfc3085bis-00.txt Status of this Memo This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and BCP 79. 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 "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/1id-abstracts.html The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html This Internet-Draft will expire on January 8, 2010. Copyright Notice Copyright (c) 2009 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 in effect on the date of publication of this document (http://trustee.ietf.org/license-info). Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Abstract This document describes a URN (Uniform Resource Name) namespace for identifying news-related data items. A news-related data item is an information resource used for news exchange that is expressed as an instance complying with a specific data schema. This may be the schema of IPTC news standards specifications such as NewsML 1 and the G2-Standards or the specification of any other body. Steidl Expires January 8, 2010 [Page 1] Internet Draft URN Namespace for news-related resources July 2009 Table of Contents 1. Introduction .................................................. 2 2. Specification Template ........................................ 2 3. Examples ...................................................... 5 4. Security Considerations ....................................... 5 5. Community Considerations ...................................... 6 6. IANA Considerations ........................................... 6 References ....................................................... 6 Author's addresses ............................................... 7 1. Introduction NewsML 1 and the G2-Standards specify XML formats for packaging multimedia news resources and items representing knowledge. These standards have been created under the auspices of the International Press Telecommunications Council (IPTC). Though the Namespace ID specified by this RFC is "newsml", the URNs specified here are intended for global use by any kind of news-related item. Their intended use is not restricted to IPTC standards. The same logical news-related data item may exist in multiple physical locations. Specifications for such items - among them NewsML 1 and the IPTC G2-Standards - allow for each item to have multiple URLs to access and retrieve it, but only a single URN as an identifier. It is the latter which uniquely identifies the resource. This document obsoletes RFC 3085. The reasons for updating RFC 3085 are: RFC 3085, issued in March 2001, specified the URN to be used when identifying individual NewsML 1 NewsItems only. Since that time the IPTC and other organisations have defined other news item formats than NewsML 1 which also require identification and do so in a slightly different way. This new RFC addresses this issue by updating the original definition. This includes meeting the formal requirements of the new RFC template for URN registrations issued by the IETF (RFC 3406). This namespace specification is for a formal namespace. 2. Specification Template Namespace ID: "newsml" Registration Information: Registration Version Number: 2 Registration Date: 2009-06-15 Steidl Expires January 8, 2010 [Page 2] Internet Draft URN Namespace for news-related resources July 2009 Declared registrant of the namespace: Name: International Press Telecommunications Council Address: 20 Garrick Street London WC2E 9BT United Kingdom Contact: Michael Steidl office@iptc.org http://www.iptc.org Declaration of syntactic structure: The identifier has the following ABNF[6] specification: This is the form used for identifying a unique resource in a NewsML instance. 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 = 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" ProviderId must be a registered Internet domain name or a subdomain name of such a domain, and must be registered, at the date given in DateId, by the organisation creating the news resource and allocating the URN to it. DateId is a date in ISO 8601 Basic Format (CCYYMMDD), and must correspond to a date at which the organisation allocating the URN was the registered owner of the domain name specified in the ProviderId. NewsItemId must be unique among all news-related data items emanating from the organisation with the same ProviderId and having the same DateId. Steidl Expires January 8, 2010 [Page 3] Internet Draft URN Namespace for news-related resources July 2009 RevisionId is an optional positive integer indicating which revision of a given data item this is. The use of the optional RevisionId must be specified by the standard of the corresponding data item. This includes requiring a mandatory use of the RevisionId by the standard of the corresponding data item. Any positive integer may be used as a RevisionId, but it must always be the case that of two instances of a data item 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. Update: when associated with NewsML 1 news items, if the news item contains one or more NewsML 1 "Update" elements, then Update must be set to "U". If the news item consists only of a replacement set of NewsML 1 NewsManagement data, then Update must be set to "A". If neither of these is the case, or if the URN is not associated with a NewsML 1 news item, then Update must be omitted. Identifier uniqueness considerations: The ProviderId plus the DateId serves to uniquely identify the organisation that is allocating the URN by the requirement that the domain name of the ProviderId is registered to the organisation on the day of the DateId. That organisation is responsible for ensuring the uniqueness of the NewsItemId and for the use of any RevisionId in line with the specification of the standard of the data item schema. Identifier persistence considerations: A newsml-URN may only be allocated by an organisation that is registered with the Internet domain name of the ProviderId on the day of the DateId. As a domain name can only be registered to one organisation on a specific day the combination of date and domain name will uniquely identify that organisation as long as the information about this registration will be available. Process of identifier assignment: For a newsml-URN identified data item 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 ProviderId/DateId. Process of identifier resolution: Any resolution mechanism for newsml-URNs is optional. Providers of newsml-URN-identified data items are responsible for the Steidl Expires January 8, 2010 [Page 4] Internet Draft URN Namespace for news-related resources July 2009 provision of such a resolution service if they have decided to provide one. Rules for Lexical Equivalence: Newsml-URNs are lexically equivalent if the ProviderId, DateId, NewsItemId, and - if used - the optional RevisionId and Update indicator are all identical (case-insensitive comparison). 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: Newsml-URNs are intended for global use by any kind of news- related item. 3. Examples The following examples are representative of NewsML URNs, but may not refer to actual resources. urn:newsml:businesswire.com:20010714:20070403005477 The example above identifies all versions of an IPTC G2 item - as it omits the RevisionId urn:newsml:pressassociation.press.net:20001017:nmhp-home_news-37896:1 The example above identifies the first revision of a news item urn:newsml:afp.com:20030704:AFP_TX_PAR_20030704_114814_IHB86:2A The example above identifies the first revision of a NewsML 1 NewsItem with NewsManagement data only urn:newsml:reuters.com:20000206:IIMFFH05643_2000-02-06_17-54-01:3U The example above identifies the third revision of a NewsML 1 NewsItem with Updates elements only 4. Security Considerations There are no additional security considerations other than those normally associated with the use and resolution of URNs in general. 5. Community Considerations. Steidl Expires January 8, 2010 [Page 5] Internet Draft URN Namespace for news-related resources July 2009 The NewsML user community is moving towards the adoption of XML Schema and the use of XML formats for marking up content that is not suited to a pure textual form such as that in W3C XHTML or IPTC News Industry Text Format (NITF). At present there is no consistent way in which to refer to these other namespaces that may need to be included within NewsML and are required to be identified in a manner that allows proper validation of the complete document instance. The introduction of an additional new form of the newsml-URN designed to identify such XML Schema will provide such a mechanism. This will enable users to properly resolve the relevant namespaces to identify the Schemas in a consistent fashion. 6. IANA Considerations This RFC includes an extended URN NID registration that is to be entered into the IANA registry of URN NIDs as an update to the existing registration of the NID string "newsml". The NID string "newsml" is requested again. It was previously assigned under RFC 3085 and meets the IETF constraints for URN naming. References Normative References [1] IPTC: NewsML 1 specifications [2] IPTC: G2-Standards specifications [3] W3C, XML WG, "Extensible Markup Language (XML) 1.0 (Fifth Edition)", November 2008, [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 3406 and BCP 66, October 2002. [6] Crocker, D. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", RFC 2234, November 1997. Informative References: [7] P. Mockapetris, "DOMAIN NAMES - IMPLEMENTATION AND SPECIFICATION", RFC1035, November 1987. Steidl Expires January 8, 2010 [Page 6] Internet Draft URN Namespace for news-related resources July 2009 Author's Address Michael Steidl IPTC 20 Garrick Street London WC2E 9BT United Kingdom Email: mdirector@iptc.org Jayson Lorenzen Business Wire 44 Montgomery Street San Francisco, CA 94104 USA Email: Jayson.Lorenzen@businesswire.com Steidl Expires January 8, 2010 [Page 7]