W3C home > Mailing lists > Public > www-tag@w3.org > September 2009

Re: Alternative dereference behavior

From: Jonathan Rees <jar@creativecommons.org>
Date: Mon, 28 Sep 2009 20:33:22 -0400
Message-ID: <760bcb2a0909281733r2ff85cc5p1b96d10b7445230e@mail.gmail.com>
To: Larry Masinter <masinter@adobe.com>
Cc: Dan Connolly <connolly@w3.org>, "www-tag@w3.org" <www-tag@w3.org>
On Mon, Sep 28, 2009 at 6:03 PM, Larry Masinter <masinter@adobe.com> wrote:
> A URI (or URL or IRI or whatever) is a communication from a
> URI producer to a URI consumer, which identifies a resource
> the URI producer wants the URI consumer to identifier.
> If the URI consumer wants to understand the communication,
> the URI consumer needs to understand what the URI producer
> intended.
> " does it leave open the possibility of conforming agents
>  using mechanisms that give answers at variance with what
>  the Web would give?"
> Consumers of URIs that use mechanisms other than the
> one indicated by the URI itself must somehow be using
> additional information that isn't contained within
> the URI itself.  I don't think it should be part of
> the "Web canon" to forbid the use of additional
> out-of-band information, but certainly such use is
> "non-conforming" within the domain of applicability.

So your answer is no: a producer/consumer pair using alternative
dereference would be non-conforming. Pray tell, to what would they be
non-conforming? And to what domain do you refer?

> One additional piece of information which is often
> necessary but not part of the URI is the timeframe
> in which access is expected. So 100 years from now,
> if an interpreter of a 100-year-old document comes
> across "http://www.netscape.com", the interpreter
> (a URI consumer) may well use some out of band
> information to understand and interpret what was
> likely meant by the producer of that URI.
> Other examples of out-of-band information come from
> local configuration information (intranet users
> allowing WINS resolution of domain names) and
> "transparent proxies", where organizations intercept
> HTTP traffic and try to redirect requests to local
> caches as a way of reducing net bandwidth use
> and improving latency.

Other examples of "out-of-band" information include technical
standards and other technical documentation, and past resolution
behavior. But I didn't want to talk about the *reasons* for
communicating parties to desire nonstandard dereference, since these
are quite variable.

> There is no simple way to normatively ALLOW or
> DISALLOW a URI consumer from using out-of-band
> information to pick a different resolution method,
> but this doesn't change the fact that the URI
> producer's *meaning* is the one indicated by the
> URI scheme itself, even if the producer is aware
> of and takes into consideration the consumer's
> likely additional behavior.

I didn't want to introduce "meaning" into this conversation. I'm not
sure how it bears on it. I also don't understand how you justify this
assertion - do you know of a consensus document that says this, or
implies this? Or that even talks about the meaning of a URI?

I think one of the points I want to make is the lack of consensus on
the question of "correct" (or conforming) dereference. It's very easy
to have positions, but very difficult to justify them as being
anything other than what one thinks.

> I think the discussion of "meaning" without
> being clear about "to whom" and "when" is
> very difficult and leads to incorrect
> conclusions and contradictions; be
> careful to use "meaning" as verb (someone
> means something at some point in time)
> rather than an attribute (X has meaning
> Y).

I didn't discuss meaning at all. I was careful to limit the question
to dereference.

Received on Tuesday, 29 September 2009 00:34:09 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 22:56:30 UTC