You can model the time with a random variable, and schedule the events randomly. Hope it helps, -chen xuan On Sat, 16 Jun 2001, fanrui wrote: > Hi, > > I know that in ns, we can shedule an event to occur at some sime > using the command 'at'. But if there are many events need happen > randomly, how could I do? > -- Xuan Chen USC/ISI