Queuing with Special Service

Queuing with special service is defined as queuing where there are several types of units to be serviced, some of which may only be serviced at certain service points while others may be serviced at all points. The simplest system of this type (only one type of special service is offered at m of the a service points) is discussed. It is shown that service is poorer (as measured by delay time and delay probabilities) for both normal and special units than that obtained in the ordinary queue situation. Methods for formulating the equations for exponential and constant holding times are discussed and two rough approximations that yield reasonable values for the delays and delay probabilities of the special units are described. An example of the rough approximations is illustrated.