Getting Started

A Simple M/M/1 Queueing Model

A simple example illustrates some of the concepts involved in model building. The network shown in Figure 1.6 models an M/M/1 queue. Transactions originate at the source node Sampler. The user chooses the interval between transactions, called the inter-arrival time, to be a sample of a random variable (from one of several distributions), a fixed amount, or the value of a variable read from a SAS data set. By default, the inter-arrival time is an observation of an exponential random variable with parameter 1. This models a Poisson process for transaction arrivals.

Figure 1.6: An M/M/1 Queueing Model

A Simple M/M/1 Queueing Model

Queueing

Service

Statistics