Network Working Group S.J.D. Cox Internet-Draft Commonwealth Scientific and Industrial draft-sjdcox-cgi-urn-00.txt Research Organisation Intended status: Informational Expires: April 4, 2008 October 4, 2007 A URN namespace for the Commission for the Management and Application of Geoscience Information (CGI) Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of 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/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire on April 4, 2008. Copyright Notice Copyright (C) The IETF Trust (2007). Abstract This document describes a URN (Uniform Resource Name) namespace that is engineered by the Commission for the Management and Application of Geoscience Information (CGI) for naming (i) persistent resources published by the CGI, and (ii) resources published by organizations that wish them to be used in the context of services conforming to protocols and agreements issued by CGI. The formal Namespace identifier (NID) is "cgi". 1. Introduction CGI is a Commission of the International Union of Geological Sciences (IUGS) concerned with developing best practices in the management and application of geoscience information. The active membership is primarily drawn from organizations with statutory responsibility for providing geoscience information to external users (e.g. Geologic Cox draft-sjdcox-cgi-urn-00.txt [Page 1] Internet-Draft A URN namespace for the CGI October 2007 Surveys). An important focus of activity is the development of standards for networked data interchange, to complement or supersede the traditional map product. A number of documents, definitions, and other artefacts, are required to support this. CGI wishes to provide persistent, location- independent Identifiers for these resources. In addition, organizations that subscribe to the interchange standards proposed by CGI require external identifiers for data objects that are transferred. CGI wishes to provide a scheme to enable data providers to uniquely identify data, which is consistent with the requirements of the interchange framework. Products and services that conform to CGI endorsed interchange specifications enable users to exchange and process geoscience information across networks, computing platforms, and products. Interoperability in such an environment is facilitated by the use of a system of identifiers that is global in scope. CGI is the lead forum for statutory organizations which act as primary providers of technical data in this application domain. Motivated by these concerns, CGI would like to assign formal URNs to published resources in order to provide persistent, location- independent identifiers for them. The process for registering a namespace identifier is documented in [RFC3406]. The official IANA registry of URN namespaces is available online: . 2. URN Specification for "cgi" NID Namespace ID: The NID "cgi" is requested. Registration Information: Registration Version Number: 1 Registration Date: 2007-10-04 Declared registrant of the namespace: Commission for Geoscience Information (Secretariat) c/o British Geological Survey Kingsley Dunham Centre Keyworth Nottingham Nottinghamshire NG12 5GG U K Attn. Ian Jackson (ij@bgs.ac.uk) Cox draft-sjdcox-cgi-urn-00.txt [Page 2] Internet-Draft A URN namespace for the CGI October 2007 Declaration of syntactic structure: The Namespace Specific String (NSS) of all URNs that use the "cgi" NID has the following structure: urn:cgi:{CGIresource}:{ResourceSpecificString} where the "CGIresource" is a US-ASCII string that conforms to the URN syntax requirements [RFC2141] and defines a specific class of resource type. Each resource type has a specific labeling scheme that is covered by "ResourceSpecificString", which also conforms to the naming requirements of [RFC2141]. The CGI maintains a naming authority, the CGI Naming Authority (CGINA), that manages the assignment of "CGIresource" classes, and the specific registration values assigned for each resource class. Relevant ancillary documentation: The CGI Naming Authority (CGINA) provides information on the registered resources and the registrations for each. More information about CGINA and the registration activities and procedures to be followed are available at: A URN resolver is available at http://www.cgi-iugs.org/uri. The resolver provides a registry of CGI URN's used in CGI services. Identifier uniqueness considerations: The CGINA manages resources using the "cgi" NID and is the authority for managing the resources and subsequent strings associated. In the associated procedures, CGINA ensures the uniqueness of the strings themselves or permits secondary responsibility for management of well-defined sub-trees. CGI may permit use of experimental type values that will not be registered. As a consequence, multiple users may end up using the same value for separate uses. As experimental usage is only intended for testing purposes, this should not interfere with operational services. Identifier persistence considerations: CGINA provides clear documentation of the registered uses of the "cgi" NID. This is structured such that each CGIResource has a separate description and associated ResourceSpecificString with separate registration tables for elements of the strings that are separately maintained. Cox draft-sjdcox-cgi-urn-00.txt [Page 3] Internet-Draft A URN namespace for the CGI October 2007 The registration tables and information are published and maintained by CGINA on the CGI web site, indicated above. Process of identifier assignment: CGINA defines CGIResource classes used with the "cgi" NID, and specifies the process for identifier assignment for each class. These are described at and a set of registers linked from there. Each such resource may have three types of registration activities: 1) Registered values associated with CGI resources 2) Registration of values or sub-trees to other entities 3) Name models for use in experimental purposes Process for identifier resolution: The namespace is not listed with an RDS; this is not relevant. Rules for Lexical Equivalence: No special considerations; the rules for lexical equivalence of [RFC2141] apply. Conformance with URN Syntax: No special considerations. Validation mechanism: None specified. URN assignment will be handled by procedures implemented in support of CGINA activities. Scope: Global 3. Examples The following examples are representative urns that have been assigned by CGINA. urn:cgi:document:CGI:CGIIdentifierScheme identifies the document that describes the CGI Identifier Scheme. urn:cgi:register:CGI:CGIResourceClasses identifies the register of resource classes for which identifiers from the CGI scheme may be provided. Cox draft-sjdcox-cgi-urn-00.txt [Page 4] Internet-Draft A URN namespace for the CGI October 2007 urn:cgi:xmlns:CGI:GeoSciML:2.0 is the XML namespace for version 2.0 of GeoSciML which is owned by CGI. urn:cgi:schema:GGIC:MineralOccurences:1.0:XMI identifies the XMI representation of version 1.0 of the Mineral Occurrences information model owned by the Australasian Government Geologists Information Committee. urn:cgi:featureType:CGI:GeoSciML:2.0:Fault identifies the Fault feature-type from version 2.0 of the GeoSciML schema that is owned by CGI. urn:ogc:serviceType:CGI:GSML-FS:1.0 identifies version 1.0 of the "GSML-FS" service-type owned by CGI. urn:cgi:classifier:ICS:Silurian identifies the geologic period designated Silurian by the International Commission for Stratigraphy. urn:cgi:classifier:GSV:MelbourneFormation identifies the concept given the designation MelbourneFormation by Geoscience Victoria (Australia). urn:cgi:classifierScheme:ICS:StratChart:2004 identifies the 2004 edition of the Stratigraphic Chart published by the International Commission for Stratigraphy. urn:cgi:feature:USGS:2feb49bc-6755-11dc-8314-0800200c9a66 identifies a feature instance given the designation 2feb49bc-6755-11dc-8314-0800200c9a66 by US Geological Survey. urn:cgi:object:SGU:552cb080-6755-11dc-8314-0800200c9a66 identifies an object given the designation 552cb080-6755-11dc-8314-0800200c9a66 by Sveriges geologiska undersokning (Sweden). Cox draft-sjdcox-cgi-urn-00.txt [Page 5] Internet-Draft A URN namespace for the CGI October 2007 4. Namespace Considerations: There is currently no available namespace that will allow the CGI to uniquely specify and access resources, such as schemas and registries, that are required by organizations implementing CGI standards. There is also a need for other standards organizations, such as OGC to be able to access CGI specific resources. The CGI members considered use of other existing NIDs, such as those for OGC. However, these do not support the semantics required and in particular do not allow for the delegation of identifier assignment within the CGI community that is demonstrated here. 5. Community Considerations CGI standards require access to resources, such as schemas, registries, catalogues, documents, and services. In order for the larger IT community to be able to effectively implement applications that access CGI resources, a unique namespace is required. We desire these resources to be freely and openly available as a set of community resources. The design of the CGI namespace builds on the experience of the Open Geospatial Consortium (OGC) which has defined the framework of geospatial services within which CGI standards have been developed. The OGC membership has expertise in using the OGC URN [OGC-URN] [OGC-DEF], gained through implementation experiments and a variety of operational testbeds. The CGI namespace is compatible with this experience. 6. Security Considerations There are no additional security considerations other than those normally associated with the use and resolution of URNs in general. 7. IANA Considerations This document defines a URN NID registration of "cgi", which shall be entered into the IANA registry located at . Cox draft-sjdcox-cgi-urn-00.txt [Page 6] Internet-Draft A URN namespace for the CGI October 2007 8.0 References 8.1 Normative References [RFC2141] Moats, R., "URN Syntax", RFC 2141, May 1997. Available [online]: [RFC3406] Daigle, L. et al., "Uniform Resource Names (URN) Namespace Definition Mechanisms", RFC 3406, October 2002. Available [online]: 8.2 Informative References [OGC-URN] Reed, C., "A URN namespace for the Open Geospatial Consortium (OGC)", Internet Draft draft-creed-ogc-urn-02, August 2007. Available [online]: [OGC-DEF] Whiteside, A., "Definition identifier URNs in OGC namespace", OpenGIS Best Practice document, OGC 06-023r1, August 2006. Available [online]: Author's Address S.J.D. Cox CSIRO PO Box 1130 Bentley, WA, 6102, Australia Email: Simon.Cox@csiro.au Full Copyright Statement Copyright (C) The IETF Trust (2007). 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, THE IETF TRUST 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. Cox draft-sjdcox-cgi-urn-00.txt [Page 7] Internet-Draft A URN namespace for the CGI October 2007 Intellectual Property The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf-ipr@ietf.org. Acknowledgement(s) Thanks to Carl Reed for preparing the I-D "A URN Namespace for the Open Geospatial Consortium", upon which this submission is based. Cox draft-sjdcox-cgi-urn-00.txt [Page 8]