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Network Working Group                                           T. Kalin
Request for Comments: 4926                                     M. Molina
Category: Informational                                            DANTE
                                                               July 2007

                       A URN Namespace for GEANT

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 IETF Trust (2007).


   This document describes a proposed URN (Uniform Resource Name)
   namespace that would be managed by DANTE, representing European
   Research and academic networks, for naming persistent resources
   defined by GEANT, the Consortium of European Academic and Research
   Networks, its projects, activities, working groups, and other
   designated subordinates.

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RFC 4926               A URN Namespace for GEANT               July 2007

1.  Introduction

   The Consortium of European Academic and Research Networks (GEANT)
   provides high-speed, high-quality network connectivity for education
   institutions, universities, and research centres in Europe.  The
   network infrastructure is composed of several National Research and
   Education Networks (NRENs) and their European-wide interconnection,
   GEANT.  The current network is GEANT2 [6], and is the seventh
   generation of pan-European research and education network, successor
   to the pan-European multi-gigabit research network GEANT.  DANTE [7]
   is a UK-based organization representing the members of the Consortium
   and operating the GEANT2 Network.  This cooperative work is mainly
   done in the framework of EU-funded projects.  The biggest of such
   activities is currently the GN2 project [6], started in September
   2004, that follows other successful ones that have evolved the
   European Networks for Research and Education for almost two decades.
   It is expected that these activities and the network evolution will
   continue to be supported by the European Union and all European
   governments in the years to come, as they view the existence of a
   state-of-the-art network for research in Europe as being of top
   strategic importance.  We will refer to the organization involved in
   these projects and those that benefit from their outcome as the
   "GEANT community".

   The GEANT community produces many kinds of documents: specifications,
   working drafts, project reports, schemas, stylesheets, etc.  The
   community wishes to provide global, distributed, persistent,
   location-independent names for these resources.  The Uniform Resource
   Name (URN) variant of URIs meets these requirements.

   The GEANT community and other GEANT-affiliated groups would benefit
   from the GEANT URN proposal by having an easy, efficient way to
   assign globally unique, persistent identifiers to resources that they
   create.  The nature of GEANT work is that it serves the needs of many
   communities of interest.  A namespace managed so as to facilitate the
   creation, registration, and resolution of unique, persistent
   identifiers would be of great value for GEANT, its affiliates, and
   the higher education community generally.  The possibility of fitting
   the naming needs under existing namespaces has been considered, but
   the conclusion was that the number of activities and the size of the
   developers community is such that creating a lot of (possibly
   uncoordinated) dependencies from other namespaces is undesirable.

   The proposed URN namespace specification is for a formal namespace.

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RFC 4926               A URN Namespace for GEANT               July 2007

2.  Specification Template

   Namespace ID:


   Registration Information:

         Registration Version Number 1

         Registration Date: 2006-03-21

   Registrant of the namespace:

         ATTN: Maurizio Molina
         City House
         126 - 130 Hills Road
         Cambridge CB2 1PQ
         United Kingdom
         Phone: +44 1223 371340

         Contact: Tomaz Kalin
         Affiliation: DANTE
         City House
         126 - 130 Hills Road
         Cambridge CB2 1PQ

         Email: tomaz.kalin@dante.org.uk
         Phone: +386 1 430 3055

   Syntactic structure:

         The Namespace Specific Strings (NSS) of all URNs assigned by
         GEANT will conform to the syntax defined in section 2.2 of RFC
         2141, "URN Syntax" [2].  In addition, all GEANT URN NSSs will
         consist of a left-to-right series of tokens delimited by
         colons.  The left-to-right sequence of colon-delimited tokens
         corresponds to descending nodes in a tree.  To the right of the
         lowest naming authority node, there may be zero, one, or more
         levels of hierarchical naming nodes terminating in a rightmost
         leaf node.  See the section below entitled "Identifier
         assignment" for more on the semantics of NSSs.  This syntax
         convention is captured in the following normative ABNF rules
         for GEANT NSSs (see RFC 4234 [1]):

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RFC 4926               A URN Namespace for GEANT               July 2007

         GEANT-NSS        =   1*(subStChar) 0*(":" 1*(subStChar))

         subStChar       =   trans / "%" HEXDIG HEXDIG

         trans           =   ALPHA / DIGIT / other / reserved

         other           =   "(" / ")" / "+" / "," / "-" / "." /
                             "=" / "@" / ";" / "$" /
                             "_" / "!" / "*" / "'"

         reserved        =   "%" / "/" / "?" / "#"

         The exclusion of the colon from the list of "other" characters
         means that the colon can only occur as a delimiter between
         string tokens.  Note that this ABNF rule set guarantees that
         any valid GEANT NSS is also a valid RFC 2141 NSS.

   Relevant ancillary documentation:


   Identifier uniqueness:

         It is the responsibility of DANTE to guarantee uniqueness of
         the names of immediately subordinate naming authorities.  Each
         lower-level naming authority in turn inherits the
         responsibility of guaranteeing uniqueness of names in their
         branch of the naming tree.

   Identifier persistence:

         DANTE bears ultimate responsibility for maintaining the
         usability of GEANT URNs over time.  This responsibility may be
         delegated to subordinate naming authorities per the discussion
         in the section below on identifier assignment.  That section
         provides a mechanism for the delegation to be revoked in the
         case a subordinate naming authority ceases to function.

   Identifier assignment:

         DANTE will create an initial series of immediately subordinate
         naming authorities, and will define a process for adding to
         that list of authorities.  Each top-level working group of
         GEANT will be invited to designate a naming authority and to
         suggest one or more candidate names.

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RFC 4926               A URN Namespace for GEANT               July 2007

         Institutions and communities affiliated with GEANT may request,
         through their designated GEANT liaison, that they be granted
         GEANT-subordinate naming authority status.  They may propose
         candidate names for that authority.  One way for such entities
         to guarantee uniqueness of their proposed name is to base it on
         a DNS name.  That is, if, e.g., the German National Research
         and Education Network wished to be designated a subordinate
         naming authority under GEANT, the institutional GEANT liaison
         could propose to DANTE to be delegated control over names
         beginning with "urn:geant:dfn.de".  Institutions seeking
         affiliation with GEANT should send email to
         geant-submit@dante.org.uk, nominating an institutional liaison
         and providing contact information for that person.

         On at least an annual basis, DANTE will contact the liaisons or
         directors of each immediately subordinate naming authority.  If
         there is no response, or if the respondent indicates that they
         wish to relinquish naming authority, the authority over that
         branch of the tree reverts to GEANT.  This process will be
         enforced recursively by each naming authority on its
         subordinates.  This process guarantees that responsibility for
         each branch of the tree will lapse for less than one year, at
         worst, before being reclaimed by a superior authority.

         Lexical equivalence of two GEANT namespace specific strings
         (NSSs) is defined below as an exact, case-sensitive string
         match.  DANTE will assign names of immediately subordinate
         naming authorities in lowercase only.  This forestalls the
         registration of two GEANT-subordinate naming authorities whose
         names differ only in case.

   Identifier resolution:

         DANTE will maintain an index of all GEANT and GEANT workgroup
         assigned URNs on its Web site,
         http://www.dante.net/urn-geant/urn-geant.html.  That index will
         map URNs to resource identifiers, usually URLs.  GEANT-
         affiliated naming authorities will specify how to resolve the
         URNs they assign if they are resolvable.

   Lexical equivalence:

         Lexical equivalence of two GEANT Namespace Specific Strings
         (NSSs) is defined as an exact, case-sensitive string match.

   Conformance with URN syntax:

         All GEANT NSSs fully conform to RFC 2141 syntax rules for NSSs.

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RFC 4926               A URN Namespace for GEANT               July 2007

   Validation mechanism:

         As specified in the "Identifier resolution" section above,
         DANTE will maintain an index of all GEANT and GEANT workgroup
         assigned URNs on its Web site,
         http://www.dante.net/urn-geant/urn-geant.html Presence in that
         index implies that a given URN is valid.  GEANT-affiliated
         naming authorities will specify how to validate the URNs they



3.  Security Considerations

   There are no additional security considerations beyond those normally
   associated with the use and resolution of URNs in general.

4.  Namespace Considerations

   Registration of an Namespace Identifier (NID) specific to GEANT is
   reasonable given the following considerations:

   1.  GEANT would like to assign URNs to some very fine-grained
       objects.  This does not seem to be the primary intended use of
       the XMLORG namespace (RFC 3120) [3], or the more tightly
       controlled OASIS namespace (RFC 3121) [4].

   2.  GEANT seeks naming autonomy.  GEANT is not a member of OASIS, so
       becoming a subordinate naming authority under the OASIS URN space
       is not an option.

   3.  GEANT will want to assign URNs to non-XML objects as well.  That
       is another reason that XMLORG may not be an appropriate higher-
       level naming authority for GEANT.

   Some GEANT-developed schema and namespaces may be good candidates for
   inclusion in the XMLORG or possible future "EU" registry.  The fact
   that such an object might already have a GEANT-assigned URN shouldn't
   be a hindrance.  RFC 3406 [5] (which replaced RFC 2611) includes an
   explicit statement that two or more URNs may point to the same
   resource.  A resource with a GEANT-assigned Namespace Specific String
   would, of course, be given an XMLORG or EU Namespace Specific String
   as it enters the XMLORG or "EU" registry.

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RFC 4926               A URN Namespace for GEANT               July 2007

5.  Community Considerations

   The assignment and use of identifiers within the namespace are open,
   and the related rule is established by DANTE.  Registration agencies
   (the next level naming authorities) will be the European National
   Research and Education Networks and the established organizational
   cross-border formations.

   It is expected that the majority of the NRENs and all GEANT base
   activities make use of the GEANT namespace.

   After the establishment of the GEANT namespace, the consortium will,
   as soon as practical, establish a resolution service (analogously to
   other distributed pan-European services, like EduROAM, PerfSONAR,
   etc.) for the namespace clients.

6.  IANA Considerations

   IANA has registered the "geant" NID within the IANA registry of URN

7.  Normative References

   [1]  Crocker, D. and P. Overell, "Augmented BNF for Syntax
        Specifications: ABNF", RFC 4234, October 2005.

8.  Informative References

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

   [3]  Best, K. and N. Walsh, "A URN Namespace for XML.org", RFC 3120,
        June 2001.

   [4]  Best, K. and N. Walsh, "A URN Namespace for OASIS", RFC 3121,
        June 2001.

   [5]  Daigle, L., van Gulik, D., Iannella, R., and P. Faltstrom, "URN
        Namespace Definition Mechanisms", BCP 66, RFC 3406, October

   [6]  GEANT2 project's Web site, <http://www.geant2.net/>.

   [7]  DANTE's company Web site, <http://www.dante.net/>.

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RFC 4926               A URN Namespace for GEANT               July 2007

Authors' Addresses

   T. Kalin
   City House
   126 - 130 Hills Road
   CB2 1PQ
   United Kingdom

   EMail: tomaz.kalin@dante.org.uk

   Maurizio Molina
   City House
   126 - 130 Hills Road
   CB2 1PQ
   United Kingdom

   EMail: maurizio.molina@dante.org.uk

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RFC 4926               A URN Namespace for GEANT               July 2007

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