4.1 Real-Life Examples of Queuing

Consider several examples of queuing situations that we all experience in our everyday lives. In Figure 2-8, two real life examples of queuing are shown. A customer comes to a place, say, a fast food restaurant, to be served, joins the queue, and, when his turn comes, receives the service and leaves the place. The customer is served by a cashier. Behind the cashier, however, a team of workers help provide the service. How fast the service is provided can be controlled by controlling the number of workers in the pool. If the service is too slow, the restaurant manager can hire more workers and add them to the pool; if the manager considers that operation is too expensive, the manager can reduce the work force. In the former case, the customer service would improve; in the latter case, it would deteriorate.

The second example of Figure 2-8 is a typical bank example. There is a single line of customers and multiple tellers are serving the line. Whenever a teller becomes available the customer at the Head of Queue (HoQ) moves forward to the teller, receives the service...