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Re: Problems with caching header values

From: Alex Rousskov <rousskov@measurement-factory.com>
Date: Sat, 23 Aug 2003 10:42:18 -0600 (MDT)
To: Wilfred Nilsen <wilfred.nilsen@cox.net>
Cc: ietf-http-wg@w3.org
Message-ID: <Pine.BSF.4.53.0308231038160.97443@measurement-factory.com>

Do the browsers send If-Modified-Since (IMS) requests or regular GETs
when refreshing the images? If they send IMS requests, you may be out
of luck. If they send regular gets, you may want to experiment with
image headers some more: try adding Cache-Control: public as the first
Cache-Control header or removing all Cache-Control headers and adding
Expires header instead.

BTW, please keep in mind that a Cache-Control: no-cache does not mean
that that cache cannot store (cache) the object. It means the cache
has to revalidate it every time (with an IMS request, for example).



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On Thu, 21 Aug 2003, Wilfred Nilsen wrote:

> I have a page that is generated dynamically and I therefore set the
> "Cache-Control: No-Cache" header. The page contains a meta refresh tag
> and is automatically polled every so often.
> The page contains links to images that never change so in order to
> prevent the browser from attempting to fetch new versions of the
> images, I set the header value "Cache-Control: max-age=86400". The
> problem is that the browsers I have tested this with, IE 6.0 and
> Mozilla 1.13, seems to ignore the max-age header value and are always
> checking for newer versions. The browsers are set to get a new page
> when the current page is out of date.
> I also tried to set the "Expires" header but that did not help either.
> Thanks,
> Wilfred
Received on Saturday, 23 August 2003 12:42:20 UTC

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