JohnBs personal blog

Not sure what got me started looking at http compression just now but from what i’ve read i’m amazed that more people aren’t taking advantage of it to save on bandwidth and increase response times.

HTTP compression is available on both IIS and Apache. Whilst IIS (we’re talking v6.0 - previous versions of IIS were full of bugs when using HTTP compression) is able to compress static files by default it won’t compress application files. The Microsoft IIS6 pages link to an addin called ZipEnable from port80software.com. They offer a free trial but it only costs $80 when it’s over. On the port80 site there’s an analyzer to show the benefits of enabling compression. Compression is achieved at the cost of processing power but the tool has a limit to the amount of CPU it can use if the server gets hammered.

Requesting my blog page before i enable compression the tool reports the file size is 28153 bytes, if it were compressed i could reduce it to 10148 bytes achieving 65% compression and speed improvements of 2.7 times. Well, i installed the trial and using WebOptimization.com checked to see what had actually happened - before enabling compression WebOptimization reported the HTML object size as 28148 bytes, enabling compression it was reduced to 8549 bytes (using level 5 compression) so that’s around a 70% compression level.

I’m going to leave it running for a while and see how it responds but using less bandwidth can’t be a bad thing these days - plus reduced size means faster responses. Incidently, on Apache you’d want to use the mod_gzip module to enable http compression.