Network Working Group K. Best Request for Comments: 3120 OASIS, Inc. Category: Informational N. Walsh Sun Microsystems, Inc. June 2001 A URN Namespace for XML.org 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 that is engineered by the Organization for the Advancement of Structured Information Standards (OASIS) for naming persistent resources stored in the XML.org repository (such as XML (Extensible Markup Language) Document Type Definitions, XML Schemas, Namespaces, Stylesheets, and other documents). 1. Introduction The XML.org Registry is provided by XML.org as a public service where XML schemas, DTDs, stylesheets, and other documents can be shared. Documents are submitted to a repository then retrieved by others who may want to use them. These documents require unique identifiers. Motivated by these observations, XML.org would like to assign URNs to some resources in order to retain unique, permanent location- independent names for them. This namespace specification is for a formal namespace. 2. Specification Template Namespace ID: "xmlorg" requested. Best & Walsh Informational [Page 1] RFC 3120 A URN Namespace for XML.org June 2001 Registration Information: Registration Version Number: 3 Registration Date: 2001-02-05 Declared registrant of the namespace: Karl Best OASIS - Organization for the Advancement of Structured Information Standards Post Office Box 455 Billerica, MA USA 01821 Phone: +1 (978) 667 5115 Declaration of structure: The Namespace Specific String (NSS) of all URNs assigned by XML.org will have the following hierarchical structure: There is one branch at the top of the hierarchy: "objects". The Objects Hierarchy The general structure of the NSS in the names hierarchy has the form: urn:xmlorg:objects:{type}{:subtype}?:{object-id} where "type" identifies the document type (document, schema, stylesheet, entity, xmlns, etc.), the optional "subtype" provides additional information about the document type (for example, stylesheet or schema language), and "object-id" is a unique identifier for the document. The Director of Technical Operations at OASIS assigns document types, subtypes, and all unique identifiers. Relevant ancillary documentation: None Identifier uniqueness considerations: Identifier uniqueness will be enforced by the Director of Technical Operations who assigns unique identifiers to all documents identified by URN. Best & Walsh Informational [Page 2] RFC 3120 A URN Namespace for XML.org June 2001 Identifier persistence considerations: OASIS is committed to maintaining the accessibility and persistence of all the resources that are assigned URNs. Process of identifier assignment: Assignment is limited to the owner and those authorities that are specifically designated by the owner. OASIS may assign portions of its namespace for assignment by other parties. Process of identifier resolution: The owner will distribute catalogs (OASIS TR9401 Catalogs) that map the assigned URNs to resource identifiers (e.g., URLs). A more interactive, online resolution system will also be deployed in the near future. The owner will authorize additional resolution services as appropriate. Rules for Lexical Equivalence: URNs are lexically equivalent if they are lexically identical. Conformance with URN Syntax: No special considerations. Validation mechanism: None specified. The owner will publish OASIS TR9401 Catalogs. The presence of a URN in a catalog indicates that it is valid. Scope: Global 3. Examples The following examples are not guaranteed to be real. They are listed for pedagogical reasons only. urn:xmlorg:objects:schema:xmlschema:xcatalog urn:xmlorg:objects:dtd:xml:docbook:v4.1.2 Best & Walsh Informational [Page 3] RFC 3120 A URN Namespace for XML.org June 2001 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] Goldfarb, C. F., "ISO (International Organization for Standardization) ISO 8879:1986(E) Information Processing -- Text and Office Systems -- Standard Generalized Markup Language (SGML)", 1986. [2] W3C, XML WG, "Extensible Markup Language (XML) 1.0", February 1998, . [3] W3C, Namespaces WG, "Namespaces in XML", January 1999, . [4] OASIS, Entity Mgmt. TC, "Entity Management: OASIS Technical Resolution 9401:1997 (Amendment 2 to TR 9401)", January 1994, . [5] Moats, R., "URN Syntax", RFC 2141, May 1997. [6] Mealling, M. and R. Daniel, "URI Resolution Services Necessary for URN Resolution", RFC 2483, January 1999. Authors' Addresses Karl Best OASIS, Inc. P.O. Box 455 Billerica, MA 01821 US EMail: karl.best@oasis-open.org Norman Walsh Sun Microsystems, Inc. One Network Drive MS UBUR02-201 Burlington, MA 01803-0902 US EMail: Norman.Walsh@East.Sun.COM Best & Walsh Informational [Page 4] RFC 3120 A URN Namespace for XML.org June 2001 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. Best & Walsh Informational [Page 5]