Analysis of cyclic queueing networks with finite buffers and blocking before service

Abstract

We consider cyclic queueing networks with exponential servers and finite buffers. The blocking mechanism we consider is blocking-before-service, i.e., a server is allowed to start processing a job only if a space is available in the next queue. We present an approximate technique for analyzing such networks based on a decomposition approach. We first consider the case where at least one buffer has an infinite capacity. The network is decomposed into a set of M/M/1 x/ K queues. An iterative algorithm for calculating the performance parameters is proposed. This technique is then extended to the case where all queues have finite capacity. Numerical experiments show that this technique provides a fairly good estimate of the throughput and the average queue lengths.