- From: Patrick Stickler <patrick.stickler@nokia.com>
- Date: Mon, 18 Feb 2002 12:13:15 +0200
- To: Patrick Stickler <patrick.stickler@nokia.com>, ext Tim Bray <tbray@textuality.com>, WWW TAG <www-tag@w3.org>
In Tim Bray's recent discussion of the namespace issue in >> http://www.textuality.com/tag/Issue8.html Tim defines a "namespace document" as whatever one might retrieve from an HTTP GET on an 'http:' URL, if such is used as the namespace URI, and suggests that the namespace document would be a RDDL instance (presumably XML). I would like to propose an alternative interim treatment which is similar in nature to the RDDL approach, and in fact would adopt the RDDL vocabulary in its realization, but which would be more forward-looking towards a time whtn such knowledge would not be tied to HTTP for retrieval and not expressed only in XML, but would be accessible by more generalized, transparent means and have an RDF foundation. Let us redefine a "namespace document" to be an RDF instance (using the RDDL vocabulary, and perhaps other vocabularies as well) which provides knowledge *relevant to* the use of the namespace but not merly about the namespace itself, alone. This RDF instance would provide knowledge about any and all resources which the owner of the namespace felt may be relevant and useful to anyone using any architectural component related to that namespace. Thus, it would describe vocabularies, document models, schemas, software components, style sheets, discriptive prose, etc. each of which would have URIs distinct from that of the namespace. The URIs denoting these resources need not be http: URLs, nor even URLS or URNs, but can be any class of URI whatsoever. And the descriptions about each resource would be specfic to that resource, not the namespace, which has no real properties apart from punctuation and providing a point of intersection for the trully interesting resources described in such an RDF namespace document. Later, in the future, when such RDF knowledge can be retrieved by means other than from namespace documents and HTTP, such as via global, distributed knowledge registries, and thus not bound to the use of http: URLs, the need for such "namespace documents" would dissappear, and also all benefit of using http: URLs as namespace URIs -- yet applications would already be used to working with such generalized knowledge and how it is obtained would remain a triviality. Furthermore, such an approach permits applications to maintain local knowledge bases about known resources, possibly also caching web retrieved knowledge for offline use, or augment that with any number of dedicated registries, providing a more flexible, scalable knowledge based solution -- hampered only temporarily by transparent, global web-accessibility of such knowledge, yet architecturally sound both now and in the the future when such accessibility issues are resolved. Owners of namespaces not based on http: URLs can still author and publish RDF namespace documents -- for installation locally to any system using architectural components grounded in that namespace, and for future propagaion into global registries. Such an interim solution would meet the immediate needs of specialised, constrained HTTP based solutions while facilitiating and encouraging work towards a more generalized, long term solution. Eh? Cheers, Patrick -- Patrick Stickler Phone: +358 50 483 9453 Senior Research Scientist Fax: +358 7180 35409 Nokia Research Center Email: patrick.stickler@nokia.com
Received on Monday, 18 February 2002 05:11:58 UTC