Date: Fri, 3 Dec 1993 13:21:08 -0800 (PST)
From: David Robison <robison@nwnet.net>
Subject: Re: URN functionality from URLs
To: Terry Winograd <winograd@interval.com>
In-Reply-To: <9312030150.AA09349@interval.interval.com>
Message-Id: <Pine.3.87.9312031308.B28996-0100000@norman.nwnet.net>
First, I want to thank Terry for the wonderful synopsis of the recent
discussion on url/urn.
Second, I want to propose that the STANF "protocol" be changed to BERK
(Banal Exercise in Redolent Knaming). ;-)
But seriously, I am a little nervous about this proposal. Terry's
distinction between present-oriented (url) vs. past-oriented (urn) is
useful.
viz.
> A URL is inherently present-oriented.
> The operational semantic grounding of
> <URL:HTTP://pcd.stanford.edu/courses/cs247.ps> is "Whatever the host
> pcd.stanford.edu will send you when you give it the request string
> 'courses/cs247.ps' ". There are no guarantees that you will get the same
> thing twice from the same request (for an example, try
> <URL: HTTP://www.cis.ohio-state.edu:84/>), that you won't get the same
> thing from many different requests, etc.
>
> On the other hand, the semantic grounding of a URN such as
> <URN://ISBN/0-201-11297-3> is past-oriented: it refers to "The unique item
> to which the ISBN has previously assigned the number 0-201-11297-3"
> regardless of where it is or what is happening now (or even whether the
> ISBN organization still exists, or the item is out of print, or...)
To me, to create a URN with STANF is to create a present-oriented URN.
Or is that what you want?
It is my understanding (and hope) that the URN would be static. It seems
to me that libraries would be good candidates for performing name
resolution (I can't remember what the new term for this is, or am I right
on this one?). If all URNs must be resolved into multiple URLs, then the
process obviously needs to be performed a multiple(!) locations.
Libraries already perform this service in terms of ISBN -> Call#. Except
in the case of the URL, there will be more than one, and it need not be
local. The STANF proposal gives the feeling that the URN is locally
oriented, when it really shouldn't be.
Hope I am making sense, but it is Friday.
David
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David F.W. Robison robison@nwnet.net
Educational Documentation Specialist 206.562.3000(Voice)
Author, Internet Passport (5th ed.) 206.562.4822(Fax)
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