An anti-blocking control policy for tandem queueing networks

Blocking phenomena may appear in any queueing network with limited capacity queues. We propose a simple admission control policy, to decrease the risks of blocking which deteriorate the system performance. Under classical Markov assumptions, the controlled system is exactly modelled in the case of two tandem queues, and approximately modelled for more than two queues. The quality of the approximate analytical model is then assessed by comparison with simulation results. It is established that in most cases, the performance of the controlled system is much higher than that of the uncontrolled system.