Performance Models of Asynchronous Multitrunk HYPERchannel Networks

The HYPERchannel communication network based on one to four trunks, or channels is considered. We develop closed queueing models with dependent servers which characterize the network performance as a function of the number of channels, the channel load, the number of stations and the packet length distribution. For analyzing the network behavior with constant packet length we introduce techniques for representing the actual asynchronous network operation by a tractable "sequential synchronous" model. Throughput and delay measures are in this way obtained for asynchronous systems operating with constant or exponential service times. The developed approach can also be used for obtaining tractable analyses of other asynchronous systems, such as multiprocessors employing multiple-bus interconnection. In the case of HYPERchannel networks, we apply the introduced models for analyzing multi- trunk network behavior and for predicting the number of channels needed to obtain a required packet-delay/trunk-utilization performance. In HYPERchannel networks the observed results are of special significance since they are most pronounced when the number of stations is small, the situation found in the majority of operational networks.