A 64 node Clos network has been simulated using the commercial OPNET
simulation package [9]. A model of the DS link and the STC104
switch has been developed within the Macramé project for this
simulator. Results from simulation and measurement have been compared
and are shown in Figure 9, which shows the latency distribution for
64 byte packets and random traffic at 50% load. The majority of packets
pass through the network without being queued, corresponding to the
peak at 12 
s. It can be seen that the agreement between simulation
and measurement is very good.
Figure 9: A comparison of the simulated and measured latency distributions
for a 64 node Clos network
Figure 8: Network throughput versus packet transmission overhead for
a 128 node Clos network