I have tried learning about the forward and reverse proxies for sometime but got a perfect explanation from Sun’s[oracle] article ..
To keep it straight — A forward proxy is the one which stands between a client and number of other servers , example : outgoing Internet requests from corporate employees .
A reverse proxy is just exaclty the opposite, It stands before a server and number of clients.
Example : incoming requests for a corporate Web site
I am trying to setup a reverse proxy in Iplanet at the moment and would be posting the same shortly. If it might help .