Simple but Tricky Question

I have around 16 computers (P4) with One server(P4 with 3 GB RAM).

All are in LAN.

Each computer gets its own bandwith, through individual ADSL Router.

Now,

Where should I install where ?

I meant to say

Express Talk on all 16 machines and other applications ?

What should be installed on Server and what should we intsall on agent machine ?

Axon should be on the server, and Express Talk should be installed on each PC, which would then register to the Axon server.