A comparison of waiting time approximations in series queueing systems

The determination of steady-state characteristics in systems of tandem queues has been left to computer simulation because of the lack of exact solutions in all but the simplest newtorks. In this paper, several methods developed for approximating the average waiting time in single-server queues are extended to systems of queues in series. Three methods, due to Fraker, Page, and Marchal, are compared along with results gathered through GPSS simulation. Various queueing networks with Erlangian service distributions are investigated.