Approach to Evaluating Characteristics of Multichannel Loss System with FCFD Preempted Priority Discipline

In the paper we consider a multichannel loss preemptive priority system with a Poisson input and general service time distribution depending on the priority of job. Jobs of the same priority are preempted according with First Come First Displaced (FCFD) protocol. Approximate formulas are obtained for the loss probability of a prescribed priority job and some other characteristics of the system. It particular cases, the obtained formulas are exact.