> I have 5 NICs and for each one I want to transmit 1000 UDP and 128 TCP > packets *simultaneously* (using UDP and TCP sockets ofcourse.. ;-) ) With 5 NICs, you will be able to send 5 packets simultaneously. > I understand that forking or multithreading is not very feasible... > i can't imagine 5500 threads/processes..!!!! :-P I can imagine them. It's neccessary to be able to imagine them, so you learn that you want to avoid them. If not sufficient, even try to do that, so you know that you have to avoid them. :-) > any directions?? man 2 poll If that is not sufficient, get an N-processor SMP, and fork about N times, spreading the work. best regards Patrick - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html