You may want to read this
FAQ. It explains how to run clinet and server on different hosts.
However, if you build a solution around IceStorm, you would not get a peer-to-peer application. Instead, you would simply end up with a centralized solution that uses IceStorm as the central server (instead of a server of your own).
I'm sorry, but I can't explain here how to write applications that are truly peer-to-peer--that is out of scope for the support we can provide in this forum.
Cheers,
Michi.