Z -iteration

Multiple-class multiple-resource (MCMR) systems, where each class of customers requires a particular set of resources, are common. These systems are often analyzed under steady-state conditions. We describe a simple method, referred to as Z-iteration , to estimate both transient and steady-state performances of such systems. The method makes use of results and techniques available from queueing theory, network analysis, dynamic flow theory, and numerical analysis. We show the generality of the Z-iteration by applying it to an ATM network, a parallel disk system, and a distributed batch system. Validations against discrete-event simulations show the accuracy and computational advantages of the Z-iteration.