Performance of a demand assignment packet switch for terrestrial and satellite networks

The authors consider a packet switch with demand time-slot assignment capability, to be used in terrestrial or satellite networks. The proposed approach attempts to optimize switch performance by scheduling a maximum number of packets within frames of fixed length, while unscheduled packets remain in buffers to be scheduled in subsequent frames. Delay analysis has been carried out under the assumption that an optimum algorithm has been utilized for this purpose. The analysis provides packet delays by finding the average number of schedule attempts before the packet is transmitted. Performance results indicate that this approach offers high throughput and low packet delays when the switch operates at heavy load. The maximum switch throughput approaches 0.9. An algorithm which can be used for the switch operation is also proposed. This algorithm maximizes the number of packets scheduled within the frame of fixed length. This is done by extracting the minimum amount of traffic from the traffic matrix so that the remaining traffic can be scheduled within one frame