comment on URI and resource ownership in WebArch document

Comments on 
	Architecture of the World Wide Web, First Edition
	W3C Working Draft 9 December 2003
	http://www.w3.org/TR/2003/WD-webarch-20031209/


The comments below address only one substantive, fundamental issue in the
document.  I have other issues with the document (for example,
authoritativeness of metadata) but these are all subsidiary to this one issue.


I actually generally like the idea of having this sort of document.  It is
a very good idea to delimit some of the principles of the World Wide Web.
(In fact, a similar document for the Semantic Web would also be very useful
- perhaps one that abided by the third architectural basis of the World
Wide Web.)


The major issue that I have with the contents of this document concerns the
related notions of ownership and authoritativeness.  I find that the
document neither adequately defines nor uses these fundamental notions and
that this problem undermines much of what the document is trying to do.

The document defines a resource as an ``item of interest''.  This is a very
broad definition, which includes things like 
1/ the Oaxaca Weather Report from WeatherExample,
2/ the Oaxaca weather report, i.e., some idealized representation of the
   Oaxaca weather, and
3/ the Oaxaca weather.
The document also uses URIs, as they are normally defined.  

The document then talks about resource owners and URI owners.  However,
unfortunately neither resource owner nor URI owner is well defined in many
situations.


Some URIs, notably many URIs in the http URI scheme, have authority
components, which can be used to define a notion of ownership.  However,
even for such URIs, the authority is often not the owner.  (For example,
dl.kr.org is probably assigned to MIT, but doing a get on http://dl.kr.org/
does not return a page that is owned by MIT.  In fact, the true owner of
this page is Carsen Lutz.  This situation is actually quite common, where
the owner of an html document is best determined by looking for the
``maintained by'' text.)  Many other URIs (e.g.,
http://weather.example.com, xxx:yyy) simply do not have any authority or
owner.

Even if a URI has an owner, this owner does not, in general, ``enable the
URI owner to serve authoritative representations of a resource.''
Certainly there is no way that the owner of
http://weather.example.com/oaxaca, if there was one, is in any special
relationship to the Oaxaca weather or even the Oaxaca weather report, as
this owner is not also the owner (or creator or controller or ...) of the
Oaxaca weather or even the Oaxaca weather report.  (Well, I suppose that it
might be possible for some owner to actually control the Oaxaca weather,
but this is highly unlikely.)

Even for resources that are created as documents on the World Wide Web, it
is not necessarily the case that the owner of a URI that identifies a
resource that is a Web document also owned by this owner will necessarily
serve authoritative representations of this document.  There are many cases
where better information about a Web document is available from other
sources.  (Consider the caches maintained by Google, leaked versions of
documents that are only available in censored form from their owner,
documents that are only available in summary form but which can be
reconstructed by others.)

Given all these problems I don't see how the architectural principles of
the World Wide Web can be so dependent on resource ownership.  Many of the
uses of ``resource owner'' in the document do not make sense at all and
need to be removed from the document.

Peter F. Patel-Schneider
Bell Labs Research

Received on Thursday, 12 February 2004 12:32:44 UTC