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Re: RFC2396bis wording, opinions?

From: John A. Kunze <jak@ucop.edu>
Date: Thu, 3 Jun 2004 10:57:02 -0700 (PDT)
To: uri@w3.org
Message-ID: <Pine.LNX.4.44.0406030919350.15106-100000@dot.ucop.edu>

> On May 29, 2004, at 13:21, Larry Masinter wrote:
> Roy's latest:
>   Resource
>>     This document doesn't limit the scope of what might be a resource;
>>     rather, the term "resource" is used in a general sense for whatever
>>     might be assigned a URI for the sake of later identification.
>
> I'm unhappy with 'assigned', because the notion of 'assignment'
> of a URI as if it were an act, performed by some authority.

The RFC2396 "identifier" definition, in its various forms through the
years, has not helped the discussion of persistent identifiers (URNs).
Here's the only definition I've seen that allows you to talk about an
identifier breaking without immediately tripping over metaphor bugs
that have to do with broken character sequences:

   An identifier is an association between a string and a resource.

It is a feature, not a bug, that under this definition a URL ceases to
be an identifier -- becoming downgraded to a mere string of data --
when that server later responds with a 404 Not Found.  This would not
be a problem for RFC2396 because an association can be broken and you
still have a URI and its syntax, whether it identifies anything or not.

The association is made manifest by any entity (web server, vendor,
government organization, etc.) that attests to the existence and nature
of a binding between the string and resource.  On the web, a web server
attests to the binding by returning something.  There may have been an
assignment or there may have been none, but that's not important.
What's important is if an assertion about a binding can be discovered.

Without the association requirement, the identifier definition is too
open, and we'd have to admit that every string of data is an identifier.
With an association between string and resource, we don't even have to
worry whether it is "correct" because associations are only matters of
opinion anyway.  That's fine.  Correctness of the association will be
fought over at other levels.

Test:  is 1234 an identifier?

       Yes, if and only if there is some entity that vouches for it.
       You can bet, for example, that many post offices and millions
       of residents will vouch for this being the number of a house
       occupied by family X on street Y.

Test:  is http://www.ucop.edu/~jak an identifier?

       No, even though it is deceptively well-formed.  Maybe it will
       become an identifier tomorrow, but it's not one today.

-John
Received on Thursday, 3 June 2004 13:55:44 GMT

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