The Basics—Multiple-Channel, Single-Phase Model
When the demand exceeds the output of a business, either that business must become more productive, increasing its output rate to cope with the increased demand, or adding more capacity to satisfy it. In a service situation, you either reduce your average service time per server or you add more servers. In this chapter, we will expand the waiting line analysis to take into account the effects of adding more servers. In chapter 6, we will explore the alternative of reducing service time.
Figure 3.1 shows a simple multiple-channel, single-phase model M/M/s with two servers. Two queue configurations are possible: a separate line for each server and one queue feeding both servers.