Re: p6: Returning the freshest response

Martin Thomson <martin.thomson@gmail.com> Fri, 29 March 2013 15:49 UTC

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Date: Fri, 29 Mar 2013 08:48:45 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: Ken Murchison <murch@andrew.cmu.edu>
Cc: HTTP Working Group <ietf-http-wg@w3.org>
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Subject: Re: p6: Returning the freshest response
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On 29 March 2013 08:24, Ken Murchison <murch@andrew.cmu.edu> wrote:
> So the (my) question is, what can/should a cache do with multiple stored
> responses in the absence of any Vary headers, as in your example above?  Can
> the cache use proactive content negotiation headers provided in the request
> to select the stored response that the client would prefer?  Or should the
> cache not select a response and punt it to the origin server per Section
> 4.2?

An origin server is required to include a Vary header if conneg is
possible, even if conneg isn't used.