From: Michael.Mealling@oit.gatech.edu (Michael Mealling)
Message-Id: <199412290201.VAA10988@oit.gatech.edu>
Subject: Re: Library Standards and URIs
To: hoymand@gate.net (Dirk Herr-Hoyman)
Date: Wed, 28 Dec 1994 21:01:28 -0500 (EST)
In-Reply-To: <ab28129510021004cbd5@[199.227.1.68]> from "Dirk Herr-Hoyman" at Dec 28, 94 07:56:20 pm
Dirk Herr-Hoyman said this:
> Let me start by saying that I see 3 levels of use for URCs, in order of
> increasing complexity.
>
> 1) URN to URL mapping
> 2) URN to URL with minimal meta-data
> 3) URN with full meta-data
>
> I think we are mostly interested in levels 1+2 here, but that we'd like to
> keep our options open for the free wheeling type of use that would be in
> level 3.
I think that if 2 were kept simple that you could fold 1 and 2 together
as far as data records are concerned. I think the resulting system would
be more powerful.
> So, with the idea of
> creating an SGML syntax use in the simple sorts of URC meta-data, I offer
> this example:
>
> <urc>
> <urn>urn:mysite.uri/myauth/11122233</urn>
> <title>My really good resource</title>
> <author>Ima Nutt</author>
> <date>December 22, 1994</date>
> <locationGroup>
> <list>
> <item><url>http://www.mysite.com/myresource</url>
> <extent>24567 bytes</>
> <format>text/html</>
> </item>
> <item><url>ftp://ftp.mysite.com/pub/myresource.txt</url>
> <extent>12543 bytes</>
> <format>text/plain</>
> </item>
> </list>
> </locationGroup>
> </urc>
>
I can deal with this. Are you suggesting then that a URC is defined
as this limited set? If so I would like to see a level attribute to
the <urc> tag so that we can extend the complexity of URCs.
> The elements of this that are TEI syntax are:
> <title>
> <author>
> <date>
> <list>
> <item>
> <extent>
> and <locationGroup> follows the spirit of TEI tagging.
>
In addition to your additions I would add tags for signatures and possibly
SOAPS....
> This example also brings forth the issues of language and character sets.
> In SGML and TEI in particular, there has been consideration given to this
> issues, and we could piggy back on their work, if we so choose. This is
> another area which I think that if we can provide for an extensible
> framework for URCs, then so much the better.
(I always love it when I can hand off the character set/language problem
to someone else. ;-)
There is one other major problem with SGML though and that is the
impact it has on the URC resolution service. The powerful nesting makes
simple query syntaxes impossible. One of my personal requirements is that
I should be able to build a functional resolution server in a weekend with
perl. I personally am not that familiar with SGML based databases so
if someone can illustrate a decent method that is easy to implement I'd
appreciate it....
-- ------------------------------------------------------------------------------ <HR><A HREF="http://www.gatech.edu/michael.html"> <ADDRESS>Michael Mealling</ADDRESS> <ADDRESS>michael.mealling@oit.gatech.edu</ADDRESS></A>