HTTP_ACCEPT_ENCODING problems

[walovaton]

Hi, first post here.

 

I have a really weird problem with HTTP_ACCEPT_ENCODING.  I am part of a big team of PHP developers who work for a very large health company here in my country and we develop/maintain a huge web application made with PHP and Oracle 9i which is a critical mission application.

 

This application serves a big amount of concurrent users both through the Internet (40%) and Intranet (60%).  To improve performance, Apache (running on Linux) is configured with mod_deflate to compress pages on the fly and the static content as well.  This works as long as the browser claims to support some kind of encoding (such as gzip or deflate).  It works quite well and it saves a lot of bandwidth, but some of our users don't get the benefits because the server "sees" that they do not support a valid encoding.

 

I checked the browsers and they are correctly configured, IExplorer has the HTTP 1.1 and HTTP 1.1 in proxy connections activated and Firefox has the network.http.accept-encoding parameter with the value of "gzip,deflate".  I even installed the Live HTTP Headers plugin in Firefox and I can confirm that the browser is sending the following header: "Accept-Encoding: gzip,deflate".  Still it doesn't work.

 

When I print the value of $_SERVER['HTTP_ACCEPT_ENCODING'] in PHP it has a value of "default" which is very strange to me.  I mean the browser sends "gzip,deflate" but the server gets "default"... what the f*** is that?? why is this happening??

 

You can check the validation page here:

http://www.ciklos.com.co/ciklos/http_encoding.php

 

If the text is blue it means your browser is ok and supports data compression.  If it's red it means your browser doesn't support compression so you will get an uncompressed version of the content wasting bandwidth.

 

I don't know where the problem is, the users affected are about 7% and all of them are connected through the Internet.  I suppose the problem is somewhere with the Internet provider but they don't have a clue either.

 

Has anyone seen a problem like this?? what can I do to solve this?? I'd really like to understand what is happening here.

 

Thanks in advance for your help.