Re: Don't put descriptive info in a URI, only identifying info

From: Gomer Thomas (gomer@lgerca.com)
Date: Mon, Dec 21 1998


Message-ID: <367EA0BA.B24514F7@lgerca.com>
Date: Mon, 21 Dec 1998 14:25:46 -0500
From: Gomer Thomas <gomer@lgerca.com>
To: Dan Connolly <connolly@w3.org>
CC: ietf-url@imc.org, www-tv@w3.org
Subject: Re: Don't put descriptive info in a URI, only identifying info

Dan,

My own interpretation of this requirement is that the "location" of a
resource in a TV broadcast environment very often has a time dimension
as well as a network address dimension.

I believe that in most, if not all cases, the time dimension will be
specified by identifying the "event" (TV program, in ordinary
terminology), with perhaps in some cases an offset relative to the start
of the event, rather than by explicitly specifying a clock time.

Gomer Thomas

Dan Connolly wrote:

> In a review of a draft of requirements for a TV URL scheme[1],
> I just noticed:
> |4.The URI scheme MUST support for OPTIONAL information
> |     from which it MUST be possible for a receiver to determine
> |     the time period(s) within which the resource can be retrieved
> |     from the (also resolved) location.
>
> This conflicts with a design principle I hold about URIs,
> explained in my message to the uri list in Feb 1997[2]:
>
> |If you're talking about "the document XYZ, which has title
> |ABC" then then ABC must not be part of the identifier. Because
> |you might want a reference ala "the document XYZ, which
> |has author Fred" to be recognized as the same resource.
> |
> |On the other hand, you might refer to a resource using
> |a restrictive clause: "the service ZZZ that started in 1996".
> |In this case, "the service ZZZ that started in 1995" is a
> |distinct resource. So the year is part of the URL.
>
> I started to (a) ask the editors of [1] to
> cite the URL scheme guidelines[3], and (b) remove requirement
> 4 since it conflicts. But [3] doesn't say anything about
> [2], so first I'm asking for [3] to reflect [2].
>
> I think [2] provides enough text for the editors to work
> with, but if it doesn't, let me know and I'll try to
> provide some.
>
> [1] TV Broadcast URI Schemes Requirements
>                        26th November 1998
> Editors:
>      Warner ten Kate <tenkate@natlab.research.philips.com>.
>      Gomar Thomas <gomer@lgerca.com>.
>      Craig Finseth <craig@finseth.com>.
> http://www.w3.org/TV/TVWeb/TVWeb-URI-Requirements-19981126.html
>
> [2] Re: Attributes should only be there if part of the name/address
> space
> Dan Connolly (connolly@w3.org)
> Thu, 20 Feb 1997 10:05:36 -0600
> http://www.acl.lanl.gov/URI/archive/uri-96.messages/0232.html
>
> [3]
> Title           : Guidelines for new URL Schemes
> Author(s)       : L. Masinter, H. Alvestrand, D. Zigmond, R. Petke
> Filename        : draft-ietf-urlreg-guide-04.txt
> Pages           : 6
> Date            : 16-Nov-98
> ftp://ftp.ietf.org/internet-drafts/draft-ietf-urlreg-guide-04.txt
>
> --
> Dan Connolly
> http://www.w3.org/People/Connolly/



--
Gomer Thomas
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