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RE: RFC2518 (WebDAV) / RFC2396 (URI) inconsistency

From: Jim Whitehead <ejw@cse.ucsc.edu>
Date: Mon, 26 Nov 2001 15:40:54 -0800
To: "Roy T. Fielding" <fielding@ebuilt.com>
Cc: "'WebDAV'" <w3c-dist-auth@w3.org>, <uri@w3.org>
Message-ID: <AMEPKEBLDJJCCDEJHAMIIEJKDMAA.ejw@cse.ucsc.edu>
Roy Fielding writes:
> I understand that case, but don't think it is a good idea.
> URI namespaces are a form of protocol, and like all protocols
> they are occasionally subject to revision.  I prefer to identify
> such protocols with a separate URI, not a construct of the syntax.

I agree that it makes sense to have a different identifier for each revision
of a URI scheme. BUT, these identifiers do not identify the same resource as
the scheme URI.

For example, "http:" identifies

    The abstract notion of locators for Web
    resources accessed via the HTTP protocol

which is a different resource than

    The set of locators for Web resources
    accessed via the HTTP protocol and defined
    specifically by RFC 2616.

and different still from

    The set of locators for Web resources
    accessed via the HTTP protocol and defined
    specifically by RFC 2068.

even though the actual URL space in question could be the same (that is, the
abstractions are different, even if, by chance, all these abstractions refer
to the same set of URLs).

So, you could still have "http:" and two additional URI/URL/URNs for the
version-specific definitions of the http URL space.

>  But that is not just my preference -- it is also
> demonstrated by that silly "about:" URI in Netscape Navigator.  That does
> identify a resource, not the naming scheme.

Actually, since it does consistently return a resource, doesn't that make it
a URL?

> In other words, I think that "scheme:" is only a valid identifier for the
> namespace if the scheme defines it as such.

This would only be for pragmatic reasons, not for philosophic ones.

- Jim
Received on Monday, 26 November 2001 18:41:17 GMT

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