W3C home > Mailing lists > Public > uri@w3.org > July 2003

Re: Proposal: new top level domain '.urn' alleviates all need for urn: URIs

From: Michael Mealling <michael@neonym.net>
Date: 09 Jul 2003 13:26:32 -0400
To: Tim Bray <tbray@textuality.com>
Cc: Sandro Hawke <sandro@w3.org>, Patrick.Stickler@nokia.com, hardie@qualcomm.com, uri@w3.org
Message-Id: <1057771592.18993.89.camel@blackdell.neonym.net>

On Wed, 2003-07-09 at 12:58, Tim Bray wrote:
> Michael Mealling wrote:
> 
> 
> > I don't know. You're using a definition of equality drawn from OWL and
> > not from RFC 2396. I don't use OWL and thus never intended for its
> > definition of 'equality' to be used in any comments I made. When I talk
> > about URIs _universally_ I make it a point to use only terms that are
> > universal for all possible applications, past, present and future. That
> > means the only definition of equality that's available to me is the one
> > found in RFC 2396.
> 
> Note that the RFC2396bis redraft-in-progress has, in its section 6, a 
> rather more nuanced and thorough discussion of the notion of 
> "equivalence" of URIs and resources.  (Disclosure: I wrote the first 
> draft of the section).
> 
> http://www.apache.org/~fielding/uri/rev-2002/rfc2396bis.html

Yes. And even there it says this which is much more correct:


"For this reason, determination of equivalence or difference of URIs is
based on string comparison, perhaps augmented by reference to additional
rules provided by URI scheme definitions. We use the terms "different"
and "equivalent" to describe the possible outcomes of such comparisons,
but there are many application-dependent versions of equivalence."


plus this:

And in 6.2.4 Protocol-based Normalization:

"Obviously, this kind of technique is only appropriate in special
situations."

All of which re-iterate that application-dependent 'sameness' of the end
set of bits, actions, etc is not something you can make statements about
for the generalized URI universe. BTW, I would suggest that you change
that last sentence in 6.2.4 to "Obviously, this kind of technique is
only appropriate in special situations and is not universally applicable
across URI schemes or protocols".

I remember the discussion at the BOF on this document and one of the
suggestions was to create another name for items that we humans call
resource but which don't yet have URIs bound do them or which we would
like to talk about outside the URI-constrained universe. We never agreed
on such a word but I still think it has utility in fixing this
discussion about URIs, Resources and 'sameness'....

-MM
Received on Wednesday, 9 July 2003 13:27:54 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 21:25:06 UTC