(N)) FIGURE E.2 Normalized saturated throughput evaluated by simulation for output queueing crossbar network. A theoretical curve is also reported for comparison. Similar results can be obtained with input queueing. from the normal working region. As far the buffer position is concerned, the behavior is as expected, with a mean delay much shorter for output buffering. Various analytical expressions have been obtained for the average delay 8 in our condi- tions. We want to remember only the expression introduced in [3]: (E.2) It is simple to verify that the simulation curves are quite near to the theoretical curve. Moreover, the important property that the average delay does not depend practically on N for great N results is evident from the equation. Average delay (slots) Analytical Simulated Input Output queues queues Offered traffic (Pin) FIGURE E.3 Average delay in number of slots evaluated by simulation for output queueing and input queueing crossbar network. A theoretical curve is also reported for comparison and the curves are calculated for large N. Appendix E: Space Division Switch Fabric Performance Evaluation E.3 Banyan Switch Fabrics Considering a Banyan network under synchronous operation with blocked packets dropped by the source, analytical results for the throughput at saturation are available [1]. The throughput THE stage Banyan network constructed starting an m from d X d elementary crossbar switches (where d is a prime number) can be expressed in the form of a recurrence relation: (E.3) where it is intended that To=1. The analytical results from the aforementioned expression, which agree very closely with the results from the simulation model, are reported in Figure E.4 besides the results for the crossbar switch fabric reported here for comparison. The throughput at saturation with the packet source resending blocked packets is also eval- uated by simulation and shown for a slotted Banyan network in Figure E.4. It is approximately 8% lower than the throughput with blocked packets dropped. This 