W3C home > Mailing lists > Public > www-talk@w3.org > November to December 2001

RE: What is at the end of the namespace?

From: <Patrick.Stickler@nokia.com>
Date: Wed, 14 Nov 2001 15:57:27 +0200
Message-ID: <2BF0AD29BC31FE46B78877321144043114C094@trebe003.NOE.Nokia.com>
To: a.powell@ukoln.ac.uk, sean@mysterylights.com
Cc: www-talk@w3.org, uri@w3.org


> -----Original Message-----
> From: ext Andy Powell [mailto:a.powell@ukoln.ac.uk]
> Sent: 14 November, 2001 01:49
> To: Sean B. Palmer
> Cc: Stickler Patrick (NRC/Tampere); www-talk@w3.org; uri@w3.org
> Subject: Re: What is at the end of the namespace?
> 
> 
> On Wed, 7 Nov 2001, Sean B. Palmer wrote:
> 
> > Hi Patrick,
> > 
> > I would suggest that perhaps uri@w3.org would be an even more
> > appropriate forum for this debate? Whatever the case, I'll send this
> > to www-talk, BCC'ing uri, and you can decide where to follow-up to.
> > 
> > > To define e.g. an 'http:' URL which is never intended to
> > > resolve to anything is IMO contrary to the defined
> > > semantics for such URLs and thus bad practice.
> > 
> > No; you are implying that there is a default base of semantics for
> > HTTP identifiers, that they are intended to resolve to a set of
> > documents, or somesuch. HTTP makes no such assumption;
> 
> If the http URI is defined by RFC 2616 (as indicated by 
> section 2.1.1 of
> http://www.w3.org/TR/uri-clarification/), then section 3.2.2 
> of the RFC
> seems pretty clear
> 
> --- cut ---
> 3.2.2 http URL
> 
>    The "http" scheme is used to locate network resources via the HTTP
>    protocol. This section defines the scheme-specific syntax and
>    semantics for http URLs.
> 
>    http_URL = "http:" "//" host [ ":" port ] [ abs_path [ "?" query ]]
> 
>    If the port is empty or not given, port 80 is assumed. The 
> semantics
>    are that the identified resource is located at the server listening
>    for TCP connections on that port of that host, and the Request-URI
>    for the resource is abs_path (section 5.1.2). 
> --- cut ---
> 
> I.e. there are some defined semantics that http URIs resolve 
> to something
> located on a server?  Is the RFC wrong, or am I mis-interpretting it?
> 
> Having said that, I accept that current http URI usage goes 
> well beyond
> this, i.e. people are assigning http URIs to all sort of 
> things, 

This is my assertion.

> and that
> we've probably got past the stage where it is worth having 
> the argument.

Well, it'll take awhile to turn the boat around, but I think
it's worth trying...


> A question...
> 
> If I make an RDF statement about
> http://www.w3.org/1999/02/22-rdf-syntax-ns#, am I making a 
> statement about
> a conceptual namespace, or about the RDFS resource that is at 
> that URI?
> In either case, how do I make a statement about the other one?


I'm about to submit a number of I-D's to the IETF for several
URI schemes, including the following two, which address your
question:

Web Resource:

http://www.w3.org/1999/02/22-rdf-syntax-ns#   
 = the web resource (if any ;-)

URI Reification:

uri:http://www.w3.org/1999/02/22-rdf-syntax-ns#  
 = the reified URI of the web resource

e.g.

   <rdf:Description rdf:about="doi:10.92881929382">
      <dc:creator>Bob</dc:creator>
   </rdf:Description>
   <rdf:Description rdf:about="uri:doi:10.92881929382">
      <dc:creator>DOI's-R-Us</dc:creator>
   </rdf:Description>

in which case, Bob created the resource but the URI
itself was minted by the DOI agency DOI's-R-Us

--

Namespace Reification and Prefixation:

xmlns:rdf:http://www.w3.org/1999/02/22-rdf-syntax-ns#
 = the namespace, with associated namespace prefix

xmlns::http://www.w3.org/1999/02/22-rdf-syntax-ns#
 = the namespace, with no namespace prefix

--

I intend to proactively support the URI registration process,
taking account of all comments, suggestions, criticisms, etc.
with the goal of seeing the above URI schemes registered
(along with some others ;-)

These two URI schemes belong to the class of URIs called
Uniform Resource Primitives (URP) as defined in section 1.1.2 of

http://www-nrc.nokia.com/sw/X_Values_URI.pdf

which is also being revised and expanded as an I-D.

Regards,

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 Wednesday, 14 November 2001 09:04:39 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Wednesday, 27 October 2010 18:14:26 GMT