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Re: Expires, Last-Modified, Pragma: no-cache etc.

From: Jean-Philippe Martin-Flatin <syj@ecmwf.int>
Date: Fri, 18 Aug 1995 11:00:16 +0100
Message-Id: <9508181100.ZM2970@helena>
To: Roy Fielding <fielding@beach.w3.org>
Cc: http wg discussion <http-wg%cuckoo.hpl.hp.com@hplb.hpl.hp.com>
On Aug 17, 13:10, Roy Fielding wrote:
>
> >But what is the difference between the Pragma: no-cache and Pragma:
> >private?
>
> private would mean the response is intended for a single user agent
> and thus must not be stored in a shared response cache.
>
> no-cache would mean the response must not be stored in any response
> cache.

Roy,

Please correct me if I miss your point... What do we gain by having both a
'no-cache' and a 'private' Pragma in terms of functionality ? A 'shared
response cache' is basically a proxy/cache, and Pragma is meaningful to
proxies only, not to user agents. So both headers really mean "don't cache
this response in a proxy/cache", and both let a user-agent local cache free
to cache the response or not.

What's the point of adding 'private' then ? I would understand it if
'non-shared response proxy/caches' were a reality, but AFAIK, they are not !

I think both cases you described above should use 'Pragma: no-cache'.

Jean-Philippe
Received on Friday, 18 August 1995 03:02:11 EDT

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