    Internet Engineering Task Force (IETF)                       F. Dijkstra
    Request for Comments: 6453                                          SARA
    Category: Informational                                  R. Hughes-Jones
    ISSN: 2070-1721                                                    DANTE
                                                               December 2011

                 A URN Namespace for the Open Grid Forum (OGF)

    Abstract

       This document describes a URN (Uniform Resource Name) namespace that
       is engineered by the Open Grid Forum (OGF) for naming persistent
       resources.

    Status of This Memo

       This document is not an Internet Standards Track specification; it is
       published for informational purposes.

       This document is a product of the Internet Engineering Task Force
       (IETF).  It represents the consensus of the IETF community.  It has
       received public review and has been approved for publication by the
       Internet Engineering Steering Group (IESG).  Not all documents
       approved by the IESG are a candidate for any level of Internet
       Standard; see Section 2 of RFC 5741.

       Information about the current status of this document, any errata,
       and how to provide feedback on it may be obtained at
       http://www.rfc-editor.org/info/rfc6453.

    Copyright Notice

       Copyright (c) 2011 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
       (http://trustee.ietf.org/license-info) in effect on the date of
       publication of this document.  Please review these documents
       carefully, as they describe your rights and restrictions with respect
       to this document.  Code Components extracted from this document must
       include Simplified BSD License text as described in Section 4.e of
       the Trust Legal Provisions and are provided without warranty as
       described in the Simplified BSD License.

    Dijkstra & Hughes-Jones       Informational                     [Page 1]

    RFC 6453                URN Namespace for the OGF          December 2011

    Table of Contents

       1. Introduction ....................................................2
          1.1. Requirements Language ......................................2
       2. URN Specification for "ogf" Namespace ID (NID) ..................3
          2.1. Namespace ID ...............................................3
          2.2. Registration Information ...................................3
          2.3. Declared Registrant of the Namespace .......................3
          2.4. Declaration of Syntactic Structure .........................3
          2.5. Relevant Ancillary Documentation ...........................4
          2.6. Identifier Uniqueness Considerations .......................4
          2.7. Identifier Persistence Considerations ......................4
          2.8. Process of Identifier Assignment ...........................5
          2.9. Process of Identifier Resolution ...........................5
          2.10. Rules for Lexical Equivalence .............................5
          2.11. Conformance with URN Syntax ...............................5
          2.12. Validation Mechanism ......................................6
          2.13. Scope .....................................................6
       3. Examples (Informative) ..........................................6
       4. Namespace Considerations ........................................6
       5. Community Considerations ........................................7
       6. Security Considerations .........................................7
       7. IANA Considerations .............................................7
       8. Acknowledgements ................................................7
       9. References ......................................................8
          9.1. Normative References .......................................8
          9.2. Informative References .....................................8

    1.  Introduction

       The Open Grid Forum (OGF) is a standardisation development
       organisation in the field of distributed computing.  The OGF produces
       documents such as working drafts, specifications, and schemata.  For
       more information, see <http://www.ogf.org/>.

       Working groups in the OGF community have expressed the need for
       global, distributed, persistent identifiers in working drafts and
       standards.  Motivated by this need, the OGF 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.

    1.1.  Requirements Language

       The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
       "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
       document are to be interpreted as described in [RFC2119].

    Dijkstra & Hughes-Jones       Informational                     [Page 2]

    RFC 6453                URN Namespace for the OGF          December 2011

    2.  URN Specification for "ogf" Namespace ID (NID)

    2.1.  Namespace ID

       "ogf" (where "ogf" is an acronym for "Open Grid Forum").

    2.2.  Registration Information

       Registration Version Number: 1
       Registration Date: December 2011

    2.3.  Declared Registrant of the Namespace

       Technical Director
       Open Grid Forum
       P.O. Box 1738
       Muncie, Indiana  47308
       USA
       http://www.ogf.org/
       EMail: urn@ogf.org

       The position of Technical Director is currently fulfilled by Joel
       Replogle.

    2.4.  Declaration of Syntactic Structure

       The formal syntax definitions below are given in ABNF [RFC5234].

       The namespace-specific string (NSS) in the urn:ogf names hierarchy
       begins with a subnamespace identifier (SNID), followed by a delimiter
       and a subnamespace-dependent string

          OGF-URN  =  "urn:ogf:" SNID ":" SUBNAMESPACE-SPECIFIC-STRING

       where <SNID> is a unique subnamespace identifier for the
       specification, and <SUBNAMESPACE-SPECIFIC-STRING> is a unique
       identifier within the subnamespace identifier scope.

       <SNID> has the same syntax as a <NID> as defined in [RFC2141]:

          SNID  =  ( ALPHA / DIGIT )  *31( ALPHA / DIGIT / "-" )

       ALPHA and DIGIT are defined in Appendix B of [RFC5234].

       The Technical Director at OGF (or their successors) assigns SNIDs.

    Dijkstra & Hughes-Jones       Informational                     [Page 3]

    RFC 6453                URN Namespace for the OGF          December 2011

       The syntax of <SUBNAMESPACE-SPECIFIC-STRING> is dependent on the
       <SNID> and MUST be defined by a Grid Forum Document [GFD.1].  This
       document does not pose any additional restrictions to the
       <SUBNAMESPACE-SPECIFIC-STRING> other than what is defined in the NSS
       syntax as defined by [RFC2141] or its successor:

          SUBNAMESPACE-SPECIFIC-STRING  =  1*<URN chars>

       <URN chars> is defined in Section 2.2 of [RFC2141].

    2.5.  Relevant Ancillary Documentation

       The Technical Director at OGF (or their successors) will keep a list
       of assigned subnamespace identifiers and associated documentation at
       <http://www.ogf.org/urn/> [URN-OGF].

       The procedures regarding how to register a subnamespace identifier
       are described in [GFD.191] and can also be found at the above
       Website.

    2.6.  Identifier Uniqueness Considerations

       Identifier uniqueness will be enforced by the Technical Director of
       the Open Grid Forum.

       The OGF Technical Director may sub-delegate part of the namespace to
       third parties.  It will not be permissible, neither by the OGF nor
       any third party, to re-assign previously assigned URNs.  A practical
       consequence is that a previously assigned subnamespace cannot be
       re-assigned, unless additional arrangements are made to prevent
       identifier re-assignments.

    2.7.  Identifier Persistence Considerations

       The Technical Director will only assign subnamespace identifiers for
       persistent resources.

       In order to enforce identifier persistence for individual resources,
       each document defining subnamespace identifiers MUST contain a
       section on the type of resource that is specified (e.g., whether a
       URN in the subnamespace identifies a specific version of a resource,
       the latest version of a resource, a specific manifestation, or a more
       general concept).

       The namespace identifier "ogf" MUST NOT change, even if the Open Grid
       Forum changes its name or is disbanded.

    Dijkstra & Hughes-Jones       Informational                     [Page 4]

    RFC 6453                URN Namespace for the OGF          December 2011

    2.8.  Process of Identifier Assignment

       Assignment of subnamespace identifiers is limited to the OGF and
       those authorities that are specifically designated by the OGF
       Technical Director of the OGF.  The OGF may assign portions of its
       namespace (specifically, those under designated subnamespace
       identifiers) for assignment by third parties.

       The details of this process are specified in [GFD.191].

       The syntax and semantics of each subnamespace MUST be defined by a
       Grid Forum Document [GFD.1] before the corresponding SNID is
       assigned.

    2.9.  Process of Identifier Resolution

       The OGF namespace is not currently listed with a Resolution Discovery
       System (RDS), but nothing about the namespace prohibits the future
       definition of appropriate resolution methods or listing with an RDS.

       The OGF will maintain an index of all subnamespace identifiers on its
       Website <http://www.ogf.org/urn/>.  This list may refer to known
       Resolution Discovery Systems.

    2.10.  Rules for Lexical Equivalence

       The <SNID> part of URNs in the OGF hierarchy is case insensitive.
       Thus, the <SNID> MUST be case normalised before comparison.

       The rules for lexical equivalence of the
       <SUBNAMESPACE-SPECIFIC-STRING> part of URNs in the OGF hierarchy is
       specific for each SNID and MUST be defined when a SNID is assigned by
       the OGF Technical Director.  These definitions MUST include
       information about case sensitivity, and in the case of %-escaped
       octets, MUST define the exact normalisation to be used (e.g.,
       interpret as octet, interpret as UTF-8, specify type of Unicode
       normalisation factor, etc.).

    2.11.  Conformance with URN Syntax

       The intention of this document is to only restrict the syntax of the
       <SNID>.  The syntax of the <SUBNAMESPACE-SPECIFIC-STRING> follows the
       general syntax of a URN:

          SUBNAMESPACE-SPECIFIC-STRING  =  1*<URN chars>

    Dijkstra & Hughes-Jones       Informational                     [Page 5]

    RFC 6453                URN Namespace for the OGF          December 2011

       Documents defining a subnamespace identifier SHOULD specify further
       syntactic restrictions in <SUBNAMESPACE-SPECIFIC-STRING>.  It is
       RECOMMENDED that these documents forbid the assignment of URNs
       containing characters in the <reserved> set ("%", "/", "?", and "#")
       as defined in [RFC2141].  This is in accordance with Section 2.2 of
       [RFC3986].

       For forward compatibility, it is RECOMMENDED that software
       implementations that don't validate subnamespace-specific strings
       validate the syntax according to the generic rules for validating
       URIs, as defined in [RFC3986].  URIs may contain all characters
       defined in <URN chars>, including the characters in <reserved>
       (albeit they have a special meaning), as well as the characters "&"
       and "~".

    2.12.  Validation Mechanism

       The validation mechanism of URNs in the OGF hierarchy is specific for
       each SNID and SHOULD be defined when a SNID is assigned by the OGF
       Technical Director.

       URNs in the OGF hierarchy without an assigned SNID are considered to
       be invalid.

    2.13.  Scope

       Global URNs are relevant for the distributed computing community in
       general, and the Open Grid Forum in particular.

    3.  Examples (Informative)

       Since no subnamespace identifiers have been defined yet, no actual
       examples can be given.  Therefore, the following examples are not
       guaranteed to be real or even syntactically correct.

       Grid Forum Documents defining the "gfd" and "network" subnamespace
       identifiers may give the following examples.

       o  urn:ogf:gfd:136

       o  urn:ogf:network:canarie.ca:kisti-uninett-glif-001

    4.  Namespace Considerations

       The Open Grid Forum (OGF) is a standardisation development
       organisation in the field of distributed computing.

    Dijkstra & Hughes-Jones       Informational                     [Page 6]

    RFC 6453                URN Namespace for the OGF          December 2011

       The use of the OGF hierarchy is expected to be broad, including but
       not limited to usage for:

       o  Grid Forum Documents

       o  XML (Extensible Markup Language) Schemata

       o  RDF (Resource Description Framework) Schemata

       The Open Grid Forum is dedicated to openly publishing all technical
       documentation related to URNs in the OGF hierarchy and allowing
       unlimited distribution of these documents.

    5.  Community Considerations

       Members of the distributed computing community will benefit from
       persistent and globally unique identifiers for use in protocols
       developed by the Open Grid Forum.

       Practical use of the urn:ogf namespace has been detected, and a
       formal registration will allow the Open Grid Forum to document this
       usage and enforce technical review of current practices.

    6.  Security Considerations

       There are no additional security considerations other than those
       normally associated with the use and resolution of URNs in general,
       which are described in [RFC1737], [RFC2141], and [RFC3406].

       It is recommended that implementers check the OGF registry and
       documentation [URN-OGF] before assuming that a given identifier is
       valid or has a certain meaning.

    7.  IANA Considerations

       IANA has registered the "ogf" namespace identifier (NID) with a
       reference to this document in the "Formal URN Namespaces"
       sub-registry [RFC3406] of the "Uniform Resource Names (URN)
       Namespaces" registry [URN-NAMESPACES].

    8.  Acknowledgements

       The template and useful examples from [RFC3406] formed the basis for
       this document.  The authors would like to thank Joel Replogle and
       Andre Mersky for setting up the urn:ogf subnamespace registry.
       Jeroen van der Ham, Peter Saint-Andre, and Mykyta Yevstifeyev
       proofread this document and provided valuable feedback.

    Dijkstra & Hughes-Jones       Informational                     [Page 7]

    RFC 6453                URN Namespace for the OGF          December 2011

    9.  References

    9.1.  Normative References

       [GFD.191]  Dijkstra, F., Hughes-Jones, R., Newby, G., and J.
                  Replogle, "Procedure for Registration of Subnamespace
                  Identifiers in the URN:OGF Hierarchy", GFD 191,
                  December 2011, <http://www.ogf.org/documents/GFD.191.pdf>.

       [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
                  Requirement Levels", BCP 14, RFC 2119, March 1997.

       [RFC2141]  Moats, R., "URN Syntax", RFC 2141, May 1997.

       [RFC3986]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
                  Resource Identifier (URI): Generic Syntax", STD 66,
                  RFC 3986, January 2005.

       [RFC5234]  Crocker, D., Ed., and P. Overell, "Augmented BNF for
                  Syntax Specifications: ABNF", STD 68, RFC 5234,
                  January 2008.

    9.2.  Informative References

       [GFD.1]    Catlett, C., "GGF Document Series", GFD 1, April 2002,
                  <http://www.ogf.org/documents/GFD.1.pdf>.

       [RFC1737]  Sollins, K. and L. Masinter, "Functional Requirements for
                  Uniform Resource Names", RFC 1737, December 1994.

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

       [URN-NAMESPACES]
                  IANA, "Uniform Resource Names (URN) Namespaces",
                  <http://www.iana.org/>.

       [URN-OGF]  Open Grid Forum, "URN:OGF Hierarchy Registry and
                  Documentation", <http://www.ogf.org/urn/>.

    Dijkstra & Hughes-Jones       Informational                     [Page 8]

    RFC 6453                URN Namespace for the OGF          December 2011

    Authors' Addresses

       Freek Dijkstra
       SARA
       Science Park 121
       Amsterdam  1098 XG
       NL

       EMail: Freek.Dijkstra@sara.nl

       Richard Hughes-Jones
       DANTE
       City House
       126-130 Hills Road
       Cambridge  CB2 1PQ
       UK

       EMail: Richard.Hughes-Jones@dante.net

    Dijkstra & Hughes-Jones       Informational                     [Page 9]