[URNsAndRegistries-50] New issue on URNs and their uses

This note is to announce the opening of a new TAG issue which will be
known as URNsAndRegistries-50.

Scope
--------

* What kinds of URIs are appropriate for naming XML namespaces?

* What is the role of location-independent names on the Web?

* What form should public registries for XML-encoded information take,
  if any?

* What are the tradeoffs between centralized and decentralized
  management of vocabularies, and how does this interact with Web
  Architecture?


Issue background and related work
---------------------------------

This issue was  accepted by the TAG during its telcon of Mar. 15, 2005 
(formal minutes not yet accepted by the TAG, but draft available at [2].) 

A number of proposals have emerged recently for the use of URNs or
URN-like names, including at least:

  URNs for namespace names:
   (e.g. http://ietfreport.isoc.org/idref/draft-ietf-geopriv-pidf-lo/
         http://xml.coverpages.org/UBL-NDRv10-Rev1c.pdf (section 3.4.2)
         http://www.e-government.govt.nz/docs/urn-200401/index.html
         http://www.faqs.org/rfcs/rfc3622.html)

  Registries for mapping URNs or similar object to resources:
   (e.g. http://ietfreport.isoc.org/idref/rfc3688/
         http://lists.w3.org/Archives/Public/www-tag/2005Mar/att-0051/T05-SG17-050330-D-0010__MSW-E.doc)

The TAG feels that on first inspection many of these proposals
interact with the principles set out in AWWW [1] in ways which need
detailed investigation.  Relevant parts of AWWW include:

   "[a] namespace URI can be used to identify an information resource
   that contains useful information, machine-usable and/or
   human-usable, about terms in the namespace. This type of
   information resource is called a *namespace document*.

   . . .

   Good practice: Namespace documents

   The owner of an XML namespace name SHOULD make available material
   intended for people to read and material optimized for software
   agents in order to meet the needs of those who will use the
   namespace vocabulary."

    -- http://www.w3.org/TR/webarch/#namespace-document

    "Good practice: Avoiding URI aliases

    A URI owner SHOULD NOT associate arbitrarily different URIs with
    the same resource."

     -- http://www.w3.org/TR/webarch/#avoid-uri-aliases

Issue namespaceDocument-8 [3] is also obviously related.

The TAG will consider all of the above in deciding whether there is 
a need to issue guidance in this area.

Next Steps
----------

David Orchard and myself have been tasked with drafting an initial
survey of the issues involved.

ht

[1] http://www.w3.org/TR/webarch/
[2] http://lists.w3.org/Archives/Public/www-tag/2005Mar/att-0054/March152005.html
[3] http://www.w3.org/2001/tag/issues.html#namespaceDocument-8
-- 
 Henry S. Thompson, HCRC Language Technology Group, University of Edinburgh
                     Half-time member of W3C Team
    2 Buccleuch Place, Edinburgh EH8 9LW, SCOTLAND -- (44) 131 650-4440
            Fax: (44) 131 650-4587, e-mail: ht@inf.ed.ac.uk
                   URL: http://www.ltg.ed.ac.uk/~ht/
[mail really from me _always_ has this .sig -- mail without it is forged spam]

Received on Monday, 21 March 2005 16:41:48 UTC