W3C home > Mailing lists > Public > www-rdf-interest@w3.org > January 2004

RE: URI: Name or Network Location?

From: Phil Dawes <pdawes@users.sourceforge.net>
Date: Tue, 27 Jan 2004 03:46:16 +0000
Message-ID: <16405.57096.781233.726459@gargle.gargle.HOWL>
To: "Hammond, Tony (ELSLON)" <T.Hammond@elsevier.com>
Cc: 'Patrick Stickler' <patrick.stickler@nokia.com>, www-rdf-interest@w3.org

Hi Tony,

Nobody else has answered this, so I'll have a stab.

Hammond, Tony (ELSLON) writes:
 > 
 > > I simply can't fathom any real benefit to having a URI
 > > which, by definition, cannot be used to access such knowledge.
 > 
 > The reason is to keep the barrier to entry as low as possible. By explicitly
 > excluding dereference we have devised a very simple, focussed registration
 > mechanism which requires almost zero maintenance and is consistent across
 > the whole INFO namespace with a predictable behaviour (i.e. disclosure of
 > identity). This is a baseline service - think of it as something like the
 > Model T.
 > 
 > I agree that it would be useful to have resource representations sitting out
 > there on some network endpoint - but that is just way too expensive for the
 > namespaces we are interested in fostering. There are no (human) resources
 > available to maintain such an undertaking. The conclusion is that we either
 > go this zero-resolution route or we accept that many of these namespaces
 > will continue not to be represented on the Web. Which means that we will
 > continue to be frustrated by not being able to 'talk' about well-known
 > public information assets in Web description technologies.
 > 

At work we've been using tag uris for the last 6 months in our
internal RDF knowledge base (which is still reasonably small: ~50000
triples), for much the same reason as the info URI scheme was created
- that we wanted to represent abstract concepts and physical things
without the dereference baggage and confusion.

However, I've recently been convinced by Patrick's and Sandro's
arguments for using http uris to denote abstract concepts. It gives us
more flexibility in the future, for practically no cost. 
(The fact that Sandro was one of the inventors of the tag uri scheme
give his arguments additional weight.)

We are in the process of transitioning thus:

I've registered a subdomain (call it sw.foo.com for illustrative
purposes), and put a static html page up there which explains that
this URI space is for abstract URIs used on the semantic web.  
Job Done.

Now anybody who attempts to resolve a URI
(e.g. http://sw.foo.com/marketmaker/2004/01/trades#mytrade35) gets a
web page explaining that this uri represents an abstract concept or
physical object on the semantic web.

This sorts out the initial confusion that relates to using http URIs
for abstract things, since anybody who is confused is most likely to
try to resolve the http URI in an HTML web browser.

So the cost is one webpage (plus a bit of webserver config), and a DNS
subdomain entry. 

Does this make sense or am I missing something?

Cheers,

Phil
Received on Tuesday, 27 January 2004 20:14:17 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:52:04 GMT