Much of the content served by IBM® Lotus® Quickr™ can be compressed to reduce transmission time and save network bandwidth. Images are not compressed, since they are typically stored in a compressed format. Other types of content can show a significant size reduction from compression.
IBM HTTP Server supports Deflate compression through the mod_deflate
module. When it is enabled, the HTTP server checks the Accept-Encoding:
header sent by the browser to see if it can accept a compressed version of the content. If so, the HTTP server compresses the content before sending it to the browser.
Enabling Deflate compression can significantly reduce the average network traffic. There was an average of 65% network traffic reduction according to one measurement. However, there was a corresponding increase in processor utilization on the HTTP server of approximately 10%.
To enable Deflate compression in IBM HTTP Server, perform the following procedure.
Add the following lines in httpd.conf
# compress everything but images
LoadModule deflate_module modules/mod_deflate.so
DeflateFilterNote Input instream
DeflateFilterNote Output outstream
DeflateFilterNote Ratio ratio
# Insert filter
# Netscape 4.x has some problems...
BrowserMatch ^Mozilla/4 gzip-only-text/html
# Netscape 4.06-4.08 have some more problems
BrowserMatch ^Mozilla/4\\.0 no-gzip
# MSIE masquerades as Netscape, but it is fine
BrowserMatch \\bMSIE !no-gzip !gzip-only-text/html
# Don't compress images
SetEnvIfNoCase Request_URI \\
\\.(?:gif|jpe?g|png|exe)\$ no-gzip dont-vary
Parent topic: Recommended HTTP Server configuration: qp85