[thelist] in-company proxy server ignoring rules?

Winfried Huslik winfried at huslik.de
Mon May 21 12:26:27 CDT 2001


<problem>
>I just wanted to give you some feedback on the new functionality of  "One
>word a day". (...)
>However, there seem to be some bugs in the implementation, as you probably
>have heard already. When I browse through your site, other people's name
>turn up more or less unpredictably instead of mine. As far as I remember, it
>has been always been names of colleagues from my company. I do not feel it
>is a huge interference with my privacy, but it is somehow disturbing anyway.
</problem>

<reply>
(...) We have thoroughly investigated complaints about showing up other 
people's name when using our web site. This behaviour is due to the use 
of a proxy server inside your company that simply ignores all directives 
not to cache the pages. So if someone has visited a certain page it is 
(wrongly) stored on your proxy server's hard disk. For the next person 
who is visiting this page (with the same file name) the proxy server 
provides the cached page (with someone else's name in it) instead of 
getting the original from our server.
To overcome this behaviour we now add a unique extension to all file 
names which make it impossible for the proxy server to show a page from 
the cache.
</reply>

<state of the art>
<meta http-equiv="cache-control" content="no-cache, must-revalidate">
<meta http-equiv="content-base" content="http://www.owad.de/">
<meta http-equiv="content-type" content="text/html; charset=ISO-8859-1">
<meta http-equiv="expires" content="Mon, 01 Jan 2001 00:00:00 GMT">
<meta http-equiv="last-modified" content="Mon, 21 May 2001 16:43:02 GMT">
<meta http-equiv="pragma" content="no-cache">
</state of the art>

<snippet>
     for headers:
header("Location: $url?".time());
     for links:
$text='<A HREF="'.$sess->url($PHP_SELF.'?idx='."$i&".time()).'">link 
text</A>'; 
     for submits:
<FORM ACTION="<?echo($PHP_SELF.'?'.time())?>" METHOD="POST">
</snippet>

It seems to work! But ... are proxies allowed to ignore the meta tags?

Hope this helps!

Winfried




More information about the thelist mailing list