The principal investigator (PI) will study synchronous store-and-forward networks involving packetized messages of varying priority classes. The priorities may be established by transmission needs, as in the case of integrated voice and data networks in which voice transmission needs higher priority to ensure reasonable quality. Priorities may also be determined by other disparate requirements and assigned according to other criteria such as length of message or distance from source to destination. The priorities may also be established by transmission importance. The PI will also compare the effectiveness of flow control schemes which control congestion in these priority queueing networks. To this end, she has developed a Markov model and analytical techniques to determine the average delay and buffer occupancy of a single-queue multi-priority system in steady- state. The PI will extend this local analysis to treat priority networks and various associated flow control schemes. She will also develop a simulation package that allows the observation of both the transient and statistical behavior of these networks. The results of this proposed research would be applicable to the design of a wide class of networks, ranging from satellite packet networks to networks of multiprocessors.
