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Date in If-modified-since header

From: Ari Luotonen <luotonen@netscape.com>
Date: Tue, 15 Oct 1996 13:45:08 -0700 (PDT)
Message-Id: <199610152045.NAA12937@step.mcom.com>
To: http-wg mailing list <http-wg%cuckoo.hpl.hp.com@hplb.hpl.hp.com>

I have been brought up the issue of the date string used in the
If-modified-since header.  Current practice is to use the
Last-modified header, and given clock skew, it's also the only
foolproof way to do IMS requests.  Could the wording in the spec be
changed to reflect that, and eliminate this source of data
incorrectness?  Basically, change the semantics of "If-modified-since"
be "In-not-equal-last-modified".

Netscape servers and proxy were changed to use an equality check,
because there were cases, with older software, incorrectly set
timezones or machine times and daylight savings times where the dates
would be off and stale data would be rendered up-to-date.

Cheers,
--
Ari Luotonen	* * * Opinions my own, not Netscape's * * *
Netscape Communications Corp.		ari@netscape.com
501 East Middlefield Road		http://home.netscape.com/people/ari/
Mountain View, CA 94043, USA		Netscape Proxy Server Development
Received on Tuesday, 15 October 1996 13:46:53 EDT

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