Re: The <URL: Wrapper take 2

Roy T. Fielding (fielding@avron.ICS.UCI.EDU)
Thu, 15 Sep 1994 21:10:10 -0700

To: uri@bunyip.com
Subject: Re: The <URL: Wrapper take 2
In-Reply-To: Your message of "Thu, 15 Sep 1994 19:27:19 EDT."
<Pine.A32.3.90.940915181316.23173B-100000@elvis.med.Virginia.EDU>
Date: Thu, 15 Sep 1994 21:10:10 -0700
From: "Roy T. Fielding" <fielding@avron.ICS.UCI.EDU>
Message-Id: <9409152110.aa25862@paris.ics.uci.edu>

Steven D. Majewski <sdm7g@virginia.edu> writes:

> If scheme is an unknown one, then does it make much difference to know
> if it is a Locator or some more logical indicator ? ( If I don't
> know what to do with a LIFN:, I don't see that it makes much difference
> whether it denotes a Locator - i.e. an Indicator with protocol and
> access information, or is a logical indicator. Knowing that doesn't
> give me anything else to do with it. URN's on the other hand are
> distinguished because there is a next step - contact a "name broker"
> to resolve it into a URL ( or list of URL's or URC's )

Actually, there is no difference whatsoever. A URN just presents an
additional level of indirection -- the result is still the resource.
Thus, a URN is just a resource locator with a screwed-up syntax.

If the current URN draft were changed to replace colons with "/", you will
find there is no difference between the two (except that there is no URN
protocol, and thus the current "specification" is not implementable without
additional specs for the protocol). Just give it a try ...

urn://ISBN/0-201-10174-2
vs
URN:ISBN:0-201-10174-2

The former is even more readable, IMHO. The fact that it looks really lame
to say <URL:urn://ISBN/0-201-10174-2> is a fault of that choice for a
plain text delimeter. <urn://ISBN/0-201-10174-2> is much more readable,
and equally robust for automated URI finders. However, I really don't
care what the URL spec says should be the recommended delimeters in plain
text, just so long as it remains "recommended", remains in an appendix, and
refers only to plain text.

......Roy Fielding ICS Grad Student, University of California, Irvine USA
<fielding@ics.uci.edu>
<URL:http://www.ics.uci.edu/dir/grad/Software/fielding>