GENWiki

Premier IT Outsourcing and Support Services within the UK

User Tools

Site Tools


rfc:rfc5138

Network Working Group S. Cox Request for Comments: 5138 CSIRO Category: Informational February 2008

    A Uniform Resource Name (URN) Namespace for the Commission
 for the Management and Application of Geoscience Information (CGI)

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.

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
 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 artifacts, 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

Cox Informational [Page 1] RFC 5138 A URN Namespace for the CGI February 2008

 a system of identifiers that is global in scope.  CGI is the lead
 forum for statutory organizations that 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 at:
 <http://www.iana.org/assignments/urn-namespaces>

2. URN Specification for the "cgi" NID

 Namespace ID:
    cgi
 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)
 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].

Cox Informational [Page 2] RFC 5138 A URN Namespace for the CGI February 2008

    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:
    <http://www.cgi-iugs.org/CGIIdentifierScheme>
    A URN resolver is available at:
    <http://www.cgi-iugs.org/uri>
    The resolver provides a registry of CGI URNs 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.
    The registration tables and information are published and
    maintained by CGINA on the CGI web site, indicated above.

Cox Informational [Page 3] RFC 5138 A URN Namespace for the CGI February 2008

 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:
    <http://www.cgi-iugs.org/CGIIdentifierScheme>
    and a set of registers is 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 a Resolution Discovery System
    (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
  1. identifies the document that describes the CGI Identifier

Scheme.

Cox Informational [Page 4] RFC 5138 A URN Namespace for the CGI February 2008

 urn:cgi:register:CGI:CGIResourceClasses
  1. identifies the register of resource classes for which

identifiers from the CGI scheme may be provided.

 urn:cgi:xmlns:CGI:GeoSciML:2.0
  1. is the XML namespace for version 2.0 of GeoSciML, which is owned

by CGI.

 urn:cgi:schema:GGIC:MineralOccurences:1.0:XMI
  1. identifies the XML Metadata Interchange (XMI) representation of

version 1.0 of the Mineral Occurrences information model owned

      by the (Australasian) Government Geoscience Information
      Committee.
 urn:cgi:featureType:CGI:GeoSciML:2.0:Fault
  1. 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
  1. identifies version 1.0 of the "GSML-FS" service-type owned by

CGI.

 urn:cgi:classifierScheme:ICS:StratChart:2004
  1. identifies the 2004 edition of the Stratigraphic Chart published

by the International Commission for Stratigraphy.

 urn:cgi:classifier:ICS:StratChart:2004:Silurian
  1. identifies the geologic period designated Silurian from the 2004

edition of the Stratigraphic Chart published by the

      International Commission for Stratigraphy.
 urn:cgi:classifier:GSV:Lithology:UIUYG1245NN07
  1. identifies the concept given the designation UIUYG1245NN07 from

the lithology scheme published by Geoscience Victoria

      (Australia).

Cox Informational [Page 5] RFC 5138 A URN Namespace for the CGI February 2008

 urn:cgi:feature:USGS:2feb49bc-6755-11dc-8314-0800200c9a66
  1. identifies a feature instance given the designation

2feb49bc-6755-11dc-8314-0800200c9a66 by the US Geological

      Survey.
 urn:cgi:object:SGU:552cb080-6755-11dc-8314-0800200c9a66
  1. identifies an object given the designation

552cb080-6755-11dc-8314-0800200c9a66 by the Geological Survey of

      Sweden.

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 the Open Geospatial Consortium (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 implement applications that access
 CGI resources effectively, 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.

Cox Informational [Page 6] RFC 5138 A URN Namespace for the CGI February 2008

7. IANA Considerations

 This document defines a URN NID registration of "cgi", which has been
 entered into the IANA registry located at:
 <http://www.iana.org/assignments/urn-namespaces>

8. References

8.1 Normative References

 [RFC2141] Moats, R., "URN Syntax", RFC 2141, May 1997.
 [RFC3406] Daigle, L., van Gulik, D., Iannella, R., and P. Faltstrom,
           "Uniform Resource Names (URN) Namespace Definition
           Mechanisms", BCP 66, RFC 3406, October 2002.

8.2 Informative References

 [OGC-URN] Reed, C., "A URN namespace for the Open Geospatial
           Consortium (OGC)", Work in Progress, October 2007.
 [OGC-DEF] Whiteside, A., "Definition identifier URNs in OGC
           namespace", OpenGIS Best Practice document, OGC 06-023r1,
           August 2006.  Available [online]:
           <http://portal.opengeospatial.org/files/?artifact_id=16339>

9. Acknowledgement

 Thanks to Carl Reed for preparing the document, "A URN Namespace for
 the Open Geospatial Consortium", upon which this submission is based.

Author's Address

 S.J.D. Cox
 Commonwealth Scientific and Industrial Research Organisation
 PO Box 1130
 Bentley, WA, 6102, Australia
 EMail: Simon.Cox@csiro.au

Cox Informational [Page 7] RFC 5138 A URN Namespace for the CGI February 2008

Full Copyright Statement

 Copyright (C) The IETF Trust (2008).
 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.

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.

Cox Informational [Page 8]

/data/webs/external/dokuwiki/data/pages/rfc/rfc5138.txt · Last modified: 2008/02/15 01:56 by 127.0.0.1

Donate Powered by PHP Valid HTML5 Valid CSS Driven by DokuWiki