RE: TV Broadcast URI Schemes Requirements

From: Jeff Sussna (
Date: Tue, Nov 30 1999

Message-ID: <>
From: Jeff Sussna <>
To: "''" <>
Cc: "''" <>
Date: Tue, 30 Nov 1999 13:08:16 -0800
Subject: RE: TV Broadcast URI Schemes Requirements

Actually, the "U" in URI stands for "uniform", universal. There is nothing
in the URI spec that states that a given resource identifier must have
universal semantics. Just look at the "file:" scheme. Uniform just means
that the overal URI protocol is uniform in that new schemes can be
introduced without disrupting existing ones. "Channel 2" is therefore a
perfectly valid URI, just as is "file://d:".

It seems like the one thing we all agree on is that there are two levels of
TV URI: physical (channel/time) and logical (program), and that the two must
be mapped to one another. I don't really see any way of making physical
URI's "universal" without a universal physical transport protocol. IP
defines such a thing in the data world, but the TV world does not (unless
you want to refer to things by their physical location in the
electromagnetic spectrum).


-----Original Message-----
From: Craig A. Finseth []
Sent: Monday, November 29, 1999 7:54 PM
Subject: Re: TV Broadcast URI Schemes Requirements

   Yes, the same person may be creating content and assigning URI's, but a
   different person will be figuring out how to retrieve them. In the
   case, I would claim that the carousel mechanism should be hidden from the
   URI, just as packet retransmission is. The case of a show that's on at

OK.  Fair enough.

How about a box that has both an over-the-air antenna and a satellite
dish?  It needs to know if two items received (one via each) are the same.

   multiple times, that's more interesting. I think I may actually see your
   point here. I'll have to think further. I am certainly happy with the
   of a URN that maps to multiple URL's. Perhaps "channel 2 at 3:00 pm" is a
   URL and "X Files" is a URN. Hmm...

But "Channel 2" is not (part of) a URL, because it is not U(niversal)...