During the design of a new motor vehicle registration system for a state highway department, the systems analysts must decide on the number of terminals that are needed for the clerks who serve customers at the front desk. Customers can come to the counter, pay their registration renewals, and receive their stickers for the coming year. The system also provides answers to queries about registration rates for the different types of motor vehicles, the status of registration on a particular vehicle, the insurance category to which the vehicle belongs, and so on.

The systems analysts believe that one terminal will serve two clerical staff adequately. They are not sure, however, whether it will serve three without a queue developing, especially during peak periods (for example, around lunchtime).

Required: Outline how you would construct a queuing model to help the analysts with their problem. When you design your model, you should consider different ways that customers might queue for service and different ways in which they might be served by the clerks. Indicate whether you would use an open model or a closed model and the reasons for your choice. How would you validate and calibrate your model? Note that you should assume there is excess capacity with the central processor, disks, and so on.