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Re: My action item on Moby Dec, issue 14, etc

From: Roy T. Fielding <fielding@apache.org>
Date: Fri, 20 Sep 2002 11:52:47 -0700
Cc: "'Michael Mealling'" <michael@neonym.net>, www-tag@w3.org
To: "Williams, Stuart" <skw@hplb.hpl.hp.com>
Message-Id: <27B3346E-CCCA-11D6-B711-000393753936@apache.org>

> Even seen it asserted in many places that a URI unambiguously identifies 
> a
> single resource. I've not seen it asserted the other way round... that a
> resource is identified by a single URI. Such an assertion might be a
> consequence of a definition of resource like Roy's about a resource being 
> a
> conceptual mapping over time between an identifier and a set of time 
> varying
> equivalent representations.

Nope, it is N:1.  My definition of a resource does not say how many URI
identify that resource.  I don't even mention them in the same paragraph.

>> An N:1 mapping of a URI to a Resource
>> would require some way to determine more information about a Resource
>> other than its URI and that information does not exist at this layer
>> of the architecture.

No it wouldn't -- it merely recognizes their existence so that such
understanding can be used at other layers.  HTTP had a mechanism at one
point that would have provided information about the other N, but it
was removed due to lack of consensus.  CDN depends on similar notions.

Besides, right now we are talking about a document that already covers
many layers at the same time.

Received on Friday, 20 September 2002 15:02:53 UTC

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