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[URI vs. URIViews] draft-frags-borden-00.txt

From: Jonathan Borden <jonathan@openhealth.org>
Date: Thu, 21 Feb 2002 11:37:07 -0500
Message-ID: <03e401c1baf6$02ac4510$0a2e249b@nemc.org>
To: <www-rdf-comments@w3.org>
Cc: "pat hayes" <phayes@ai.uwf.edu>, <me@aaronsw.com>
Apropos the discussion of URI vs. URIviews:

Clearly the RDF community intends to identify <rdf:resource>s by URI
references.

On the other hand RFC 2396 identifies <rfc2396:resource>s by URIs. The
status of what a fragment identifier identifies is a bit unclear from the
documents and practice. We have submitted an internet draft which attempts
to clarify this.

http://www.ietf.org/internet-drafts/draft-borden-frag-00.txt

This is an early draft, and needs to be cleaned up a bit but is presented
for discussion.

To summarize:

On the HTML/HTTP web, a URI reference is resolved to a fragment of a
document by the following process:

1. URI part sent to HTTP server
2. HTTP server maps _resource_ identified by URI onto document
representation which is called an _entity_
3. Entity returned to client.
4. Client parses entity, and uses fragment identifier to obtain piece of
document for display.

In this usage, which is straightforward, a given fragment identifer e.g.
#toc is interpreted according to the rules of the returned media type
text/html directing the browser to display the table of contents.

RDF, however, uses URIreferences as opaque identifiers for resources and
this identification is outside any HTTP transaction -- hence no media type
applies. The issue is that without a media type, there is nothing to define
the syntax of a fragment identifier, or what it might identify.

See:
http://www.ietf.org/internet-drafts/draft-borden-frag-00.txt

A generic fragment identifier syntax is defined which encapsulates known
fragment identifier syntaxes:

The term "sub resource" is introduced, to define what a URI reference
identifies. The relationship between a URI reference and a "sub resource" is
the same as the relationship between a URI and a "resource

rdf:resource is the union of rfc2396:resource and draft-frags:subresource

This is intended to reflect common usage in the RDF community as well as XML
Namespaces whose names are also URI references.

Jonathan
Received on Thursday, 21 February 2002 11:39:26 GMT

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