>TCP/IP is a collision detect protocol.
> This means that when a workstation transmits a packet it listens to the traffic. When two stations transmit at the same time, they 'hear' another one was sending at the same time.
>In that case, they stop transmission, wait for a random time until the network is quiescent again.
One clarification: This applies specifically to Ethernet, not to TCP/IP (TCP/IP is a a group of related protocols) - and it will only happen if there is a "shared media" - which in modern networks would mean that several computers are connected via a hub (as opposed to a switch). Oh, and there can also be collisions in Wi-Fi (which uses a different protocol to Ethernet), precisely because the space in which the radio waves are transmitted is shared.
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