- From: Harry Halpin <hhalpin@ibiblio.org>
- Date: Tue, 27 Jun 2006 22:24:08 +0100
- Cc: W3C TAG <www-tag@w3.org>
Just to clarify, to me Roy seems to be saying that "all URIs *can* become dereferencable (although perhaps in a nonstandard manner) - which is true, but then is following it up with saying that any _Web architectural knowledge_ encoded in a scheme *should* be dereferencable. >> All URI schemes become dereferenceable as soon >> as someone can map any representation associated with the resource to >> a mechanism that accepts a string and returns a representation. >> That doesn't change the principle that namespace names should be >> dereferenceable *because* Web architectural knowledge should be >> grounded in the Web. Given the fact that any scheme *can* become capable of dereference, it makes little sense to argue that namespace names of anything should use a scheme whose purported advantage (like URN) is their non-dereferencability. Instead, given that one can dereference anything in theory, one should at least use a URI with a dereferencing mechanism that is standardized and widely deployed *in practice* like http. By underlining "Web architectural knowledge" - anything that's important to the Web as a whole, like MIME types, should obey the informal "Follow Your Nose" principle and have its description be found on the Web, not just in say, a book somewhere or a spec with no connection to a URN :) That's sensible. > Similarly, most of the uses of URIreferences in semantic web > formalizations are at best tangential to this principle, since their > intended Web functionality has nothing to do with dereferencing, and > allowing them to be dereferenced has only produced difficulties and > controversy, and adds nothing to their utility Pat and Noah are correct here - turning into a rule instead of good practice would be overkill, as URIs are often used for names without an obvious dereferencing function. The question is - if one had a a namespace URI or a SemWeb URI, and did dereference *something* at the end of it, does this help? Re the SemWeb, right now it does seem to be causing more trouble and confusion than good, but we recently put a workshop on to see if anything good could come out of this, and Pat has some interesting slides, as well as Steve Pepper available from the website [1]. There is a cost-benefit trade-off function when dealing with creating representations for the numbers of Semantic Web URIs and namespace documents, and part of the whole problem is that there's no clear standard for best practice for namespace documents or what a Semantic Web URI could return, much less tools to make the creation of such things trivial as to make the benefit higher than the cost. > Why 'must' this 'principle' be stated or even used? It helps to make the Web be "self-describing", although the notion of "self-describing" is something I think is another notion that could really use some inspection. [1] http://www.ibiblio.org/hhalpin/irw2006/ -- -harry Harry Halpin, University of Edinburgh http://www.ibiblio.org/hhalpin 6B522426
Received on Tuesday, 27 June 2006 21:24:25 UTC