Preemptive Priority Assignment in Multichannel Systems

Customers of different priorities arrive at a system in accordance with a Poisson process. The customers are serviced by c service stations using a preemptive priority discipline. When the servicing times are exponentially distributed, this paper derives expressions for the expected waiting time for inception of service, as well as the lower and upper bounds for the expected staying time and expected number of customers of each priority class (1 ≦ p ≦ r) in the system and in the line.