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Re: the hash sign

From: Perry A. Caro <caro@Adobe.COM>
Date: Thu, 10 Feb 2000 14:00:47 -0800
Message-ID: <38A3350F.805BCADA@corp.adobe.com>
To: W3C RDF-interest <www-rdf-interest@w3.org>
See Relative Uniform Resource Locators:

<http://www.w3.org/Addressing/rfc1808.txt>

It explains how # works in a URL.

The decision to use a URL for a namespace/schema needs to be made
carefully.  There are essentially two schools of thought.

One school believes that it is very useful for a namespace/schema ID to be a
real URL, which points at either a human-readable schema specification, or a
machine-readable schema, or both (Unqualified Dublin Core is a good example
of the "both").

The other school believes that there are many practical problems to using
URLs in this way, enough to recommend that URLs be avoided.  For example,
the lifetime of a schema may exceed the lifetime of a domain name.  Think of
all those mergers of dot.com and other commercial sites.  For another,
clients may not always be wired, or the server may be down, or the schema at
the other end may be out-of-date, or wrong.

The recommendation I've been making is to use a URI that could be
interpreted as a URL, but to make no promise that the resource at the other
end will ever materialize.  This allows the possibility of using a URL
(which a  URI with a made-up scheme, like DAV:, excludes), while making it
clear that no client should ever depend on a real resource being at the
other end.

Perry
Received on Thursday, 10 February 2000 17:01:21 GMT

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