Re: Fwd:HTTP server driven content negotiation

From: Michael A. Dolan (
Date: Tue, Mar 09 1999

Message-Id: <>
Date: Tue, 09 Mar 1999 05:32:28 -0800
To: Henrik Frystyk Nielsen <>, Johan Hjelm <>, Philipp Hoschka <>,
From: "Michael A. Dolan" <>
Subject: Re: Fwd:HTTP server driven content negotiation


There is a client cache.  Managing the cache is exactly what this would be
good for.   So....does this make sense?  Am I using Vary correctly?  Are
there more examples of its use?


At 01:00 PM 3/8/99 -0500, Henrik Frystyk Nielsen wrote:
>At 07:57 3/8/99 -0800, Michael A. Dolan wrote:
>>I understand.  My thinking was that one could use/invent Request fields
>>that might be useful.  For example:
>>	Vary X-profile1
>>	Vary Accept x-profiles/1
>>I've probably buggered the syntax up a little, but you get the idea...
>Ah - OK, but that would require that the recipient (a cache) knows these
>headers. If there is no cache then vary doesn't make much sense. I was
>under the impression that there were no cache anticipated in your model (or
>at least not a cache that would have to deal with different client profiles
>in which case broadcast doesn't seem to make sense in the first place).
>Or am I missing something?
>Henrik Frystyk Nielsen,
>World Wide Web Consortium
Michael A. Dolan, Representing DIRECTV,  (619)445-9070   
PO Box 1673 Alpine, CA 91903        FAX: (619)445-6122