Re: comment on URI and resource ownership in WebArch document

From: Dan Connolly <connolly@w3.org>
Subject: Re: comment on URI and resource ownership in WebArch document
Date: Thu, 12 Feb 2004 13:16:55 -0600

> On Thu, 2004-02-12 at 12:36, Peter F. Patel-Schneider wrote:
> > > On Thu, 2004-02-12 at 11:32, Peter F. Patel-Schneider wrote:
> > > > 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/
> > 
> > [...]
> 
> > > 2.2. URI Ownership
> [...]
> 
> > Well, the assumption that I see in this bit of the document is that there
> > is a mapping from the normative specifications underlying the architecture
> > of the internet that in most cases of interest determines a unique agent or
> > individual that is ultimately responsible for the information that will be
> > served up in response to dereferencing a URI.
> 
> It would help me if we can focus on what it says more than
> on apparent assumptions... 

Maybe it would help you, but my comment is not directed to the localized
wording of the document.  Instead my comment is directed to the notions
that come from an overall evaluation of the document.  

> is this much of the text OK?
>
> "The requirement for URIs to be unambiguous demands that different
> agents do not assign the same URI to different resources. URI scheme
>  specifications assure this using a variety of techniques"

Well, more-or-less.  At least it is the case that if a URI must
be globally ambiguous then it must have a single global assignment.  I don't
see, however, how URI scheme specifications assure this.  I also don't see
how forbidding different agents from assigning the same URI to different
resources prevents a single agent from assigning a URI to more than one
resource.

> >   I believe that this is very
> > seldom the case.  For example, I believe that I am ultimately responsible
> > for quite a number of web pages, even many pages whose internet authority
> > is Lucent Technologies, Incorporated.
> 
> That seems to match nicely with this bit of the text:
> 
> [[Hierarchical delegation of authority. This approach, exemplified by
> the "http" and "mailto" schemes, allows the assignment of a part of URI
> space to one party, reassignment of a piece of that space to another,
> and so forth.]]

Well, my reading of this was that it had to do with the delegations that
are actually part of the specifications.  I don't see how this gets to the
cases were an unrecorded delegation happens.

> > > > 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.
> > > 
> > > Carsen Lutz does not have complete carte blanch to write anything on
> > > that page, does s/he? The webarch text above makes it reasonably
> > > clear, to me, that the "ownership" of this URI is held by some
> > > combination of Carsen Lutz acting on behalf of some part of MIT.
> > 
> > MIT is not involved anymore, even formally.  (Maybe they never were.)
> > 
> > The authority for kr.org is KR, Inc., but KR, Inc., certainly exercises no
> > day-to-day control over the contents of http://dl.kr.org/.  In some sense,
> > kr.org did delegate control over http://dl.kr.org/ to the Description
> > Logics community who, in turn, delegated control to Carsten.
> 
> Ah; good.
> 
> >   However, I
> > do not believe that any of this delegation is accessible by software agents
> > working from Internet standards.
> 
> Some of it is...
> 
> $ whois kr.org
> [...]
> Domain ID:D6302-LROR
> Domain Name:KR.ORG
> Created On:01-Sep-1995 04:00:00 UTC
> Last Updated On:18-Nov-2003 01:07:37 UTC
> Expiration Date:31-Aug-2009 04:00:00 UTC
> Sponsoring Registrar:R63-LROR
> Status:OK
> Registrant ID:19928970-NSI
> Registrant Name:Principles of Knowledge Repres
> Registrant Organization:Principles of Knowledge Repres
> Registrant Street1:c/o Prof. Jon Doyle
> [...]
> 
> But some of it is just convention.
> 
> That's why we're writing the Web Architecture document: to fill in
> some of the conventions around the existing specs that have been
> implicit to date, and to motivate/justify these conventions in
> terms of the overall benefit of the system.

Well I don't see where in this document the informal delegation is taken
into account.

> >   Certainly the Description Logic community
> > treats http://dl.kr.org/ as a good place to go for information about
> > Description Logics, but I don't see how this translates into the contents
> > of http://dl.kr.org/ being authoritative about Description Logics,
> 
> It doesn't. I don't understand the relevance of that comment.

Well, my original comment had to do with the ownership and
authoritativeness aspects of the document.  Here is one case were it
appears to me that the document might want to make an authoritativeness
claim.  However, I don't see how authoritativeness even enters into the
picture here.

> >  let
> > alone about any other resource, except, perhaps, the resource that is the
> > current contents of the web page currently accessible at http://dl.kr.org/.
> 
> Of course.

Well, then, what is the resource identified by http://dl.kr.org/?  In
general what sorts of things count as resources for the purposes of this
document.  I don't see any delimitation of what can be a resource, and in
the absence of any delimination I, and any other reader, must be free to
consider any delimitation.

> > > >   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.
> > > 
> > > I don't think we're saying they have control over the weather...
> > 
> > I think that this indeed what is being said, or at least what is capable of
> > being derived from the document.
> 
> Which words suggest that?

Suppose, that I, as the owner of http://weather.example.com/oaxaca intend
that it identifies the Oaxaca weather.  This makes quite good sense to me.
I will serve representations of the weather in Oaxaca, including html
documents that when rendered in browsers inform users of the weather in
Oaxaca, and XML/RDF documents that contain facts about the weather in
Oaxaca.  The thrust of the document appears to me that I then become in
some way authoritative about the weather in Oaxaca (although the document
doesn't quite go this far, I agree) and thus must have some control over it.

> > > But in this example scenario, they do control the weather report.
> > 
> > I dispute this claim.  At best they control some weather report for
> > Oaxaca.  They certainly do not control *the* weather report for Oaxaca.
> 
> Yes, of course; some weather report; the one known in the Web context
> as http://weather.example.com/oaxaca . That's what I meant.

Well, this is not what is in the document.  The document always refers to
the Oaxaca weather report as if there was only one.

> > > I don't think I understand your concern.
> > 
> > My concern is that the document appears to make it possible for the owners
> > of Internet domains to claim control over arbitrary resources.
> 
> The document doesn't make this possible; it's already quite possible
> for owners of Internet domains to claim control over arbitrary
> resources, just like it's possible for anybody with a paper and
> pencil or a voice to claim control over arbitrary resources.
> 
> I still think I don't understand your concern with the text.

My main concern, as stated in my initial message, is that the document
does not adequately defines the fundamental terms it uses.  My initial
message pointed to ownership and authoritativeness as terms that are not
adequately defined in the document.  To that list I would also add
resource, identify, and represent.


> > > >   (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
> > > >  
> > > -- 
> > > Dan Connolly, W3C http://www.w3.org/People/Connolly/
> > > see you at the W3C Tech Plenary in Cannes 1-5 Mar 2003?
> > 
> > Peter F. Patel-Schneider
> > Bell Labs Research
> -- 
> Dan Connolly, W3C http://www.w3.org/People/Connolly/
> see you at the W3C Tech Plenary in Cannes 1-5 Mar 2003?
>

Received on Friday, 13 February 2004 12:09:35 UTC