WASHINGTON UNIVERSITY SEVER INSTITUTE OF TECHNOLOGY PERFORMANCE EVALUATION OF ASYNCHRONOUS TRANSFER MODE SWITCHING SYSTEMS by EINIR VALDIMARSSON Prepared under the direction of Professor

PERFORMANCE EVALUATION OF ASYNCHRONOUS TRANSFER MODE SWITCHING SYSTEMS by EINIR VALDIMARSSON ADVISOR: Professor Jonathan S. Turner December, 1994 Saint Louis, Missouri The design of switching systems is an important and active research area because it is essential to the success of broadband communication systems. The work presented in this thesis provides models that evaluate the performance of high speed Asynchronous Transfer Mode switching systems. These models help to evaluate the design trade-offs in switching systems needed to support current and future communication needs. The work has two parts. The first part provides new analytical models for buffered switching networks. Specifically, models for copy networks with various buffer schemes and a model for shared buffer Benes network with non-uniform traffic are presented. Our results show that the models are accurate for single stage networks, and close approximations for multistage networks. The second part of the work focuses on the development and use of simulation models of switching systems. Such simulation models are necessary, due to the limitations of analytical models, and can provide valuable information on many complex switching systems. To make evaluation and design of such systems easier and to gain a better understanding we have designed and implemented an efficient tool for evaluating switching systems. The tool is general enough to allow performance evaluation of a variety of different switching architectures. The novel aspects of the tool include easy network construction and interaction, and visualization and animation of network state and statistics. We have used the models provided by the simulation tool to compare various switching systems in terms of cell loss probability, cell delay, and complexity required to obtain certain performance requirements. Finally, we have used the tool to examine the transient behavior of shared buffer Benes systems and we have obtained new insights about the congestion conditions in the network. copyright by Einir Valdimarsson 1994