effectiveness of Mod_expires

Asit

Hi All,
I have a query on the mod_expires concept in context of team site. The concept of mod_expires to my understanding is a web server based caching mechanism and that means the assets are caches at the webserver end , therefore its implementation reduces the amount of time required for the web server to pick up an asset from the file system and send it as a response. It does not reduce the network latency. What it reduces is the disk I/O latency. Please let me know if my understanding is correct. If my understanding is correct it is the basis of my doubt on the claim of team site that mod_expires configuration will reduce the network latency. Also as i understand browser caching is useless for team site as IWPROXY sets the ' nocache '. Please help me clear my mind.
Thanks in advance
Cheers
Asit

Asit

Let me reframe my question : If we are saying that IWPROXY setting in Team Siter will render the browsing cache mechanism uselsess. http://devnet.interwoven.com/site.fcgi/techlib/050100. Then how is that the mod_expires setting in apache will help in caching. Will this not be overwritten by the setting in IWPROXY.