Network simulation is widely used in network research to evaluate the performance of network protocols.With the development of computer networks

network models grow in size and complexity

so execution time of simulation can be unbearably long.A parallel network simulator which runs on network of workstations is presented

the parallel network simulator is designed based on the popular sequential network simulator ns.Parallel discrete event simulation (PDES) techniques are applied to modify the event scheduling mechanism in ns.Some necessary extensions are also made to ns model library.Performance measures including speedup and memory consumption are evaluated at last.