NetPIPE is a protocol independent performance tool that visually represents the network performance under a variety of conditions. It performs simple ping-pong tests, bouncing messages of increasing size between two processes, whether across a network or within an SMP system. Message sizes are chosen at regular intervals, and with slight perturbations, to provide a complete test of the communication system. Each data point involves many ping-pong tests to provide an accurate timing. Latencies are calculated by dividing the round trip time in half for small messages ( less 64 Bytes ).