W3C home > Mailing lists > Public > http-caching-historical@w3.org > February 1996

Re: Variant IDs

From: Koen Holtman <koen@win.tue.nl>
Date: Thu, 15 Feb 1996 21:03:45 +0100 (MET)
Message-Id: <199602152003.VAA08871@wsooti06.win.tue.nl>
To: mogul@pa.dec.com (Jeffrey Mogul)
Cc: masinter@parc.xerox.com, http-caching@pa.dec.com
Jeffrey Mogul:
>
>    [Larry masinter:]
>    It's a simplification to say that as soon as any one piece of
>    information associated with a URI becomes stale, all of the rest of
>    the information should become stale too.

I agree. And, at least for URI header based content negotiation, it
would be a very expensive simplification to make as far as caching is
concerned.

>    If we make that simplification, 'freshness' applies to "the URI's
>    information" in general, rather than any particular piece of it.
>
>The problem that Koen points out is that this is not easily done,

This is not the problem I wanted to point out.  The problem I want to
point out is that the thing that is done, whatever it is, is not
easily defined in the spec.

>because a simple implementation of the variant-ID scheme allows
>repeated requests with one set of request headers to continually
>update the freshness information that applies to a different
>set of headers.

For the record, I don't think that an implementation that does allow
continual updates it is that much more simple than an implementation
that does not allow them.

>-Jeff

Koen.
Received on Thursday, 15 February 1996 20:20:00 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 19:55:57 UTC