Computational algorithms for blocking probabilities in circuit-switched networks

In this paper, we develop two new general purpose recursive algorithms for the exact computation of blocking probabilities in multi-rate product-form circuit-switched networks with fixed routing. The first algorithm is a normalization constant approach based on the partition function of the state distribution. The second is a mean-value type of algorithm with a recursion cast in terms of blocking probabilities and conditional probabilities. The mean value recursion is derived from the normalization constant recursion. Both recursions are general purpose ones that do not depend on any specific network topology. The relative advantage of the mean-value algorithm is numerical stability, but this is obtained at the expense of an increase in computational costs.The results of section 2 were presented in part at the 7th ITC Seminar on Broadband Technologies, Morristown, NJ, October 1990.Supported in part by the National Science Foundation, Grant No. CCR-9015717.