Performance of finite capacity communication and queuing systems under various service and buffer preemption policies

The authors carry out message delay and system throughput analysis for communication and telecommunications system applications which require the use of finite-capacity service systems using preemptive buffering (PB) disciplines. Such systems are of particular importance in situation where it is essential to provide short (and at times, bounded) message waiting-time delays, for messages which are selected for service. The authors analyze and compare the performance of such service systems, modeling them as finite capacity M/G/1/N queueing systems and using the service/buffering policies first-come-first-served/nonpreemptive buffering (FCFS/NPB), FCFS/PB, and last-come-first-served/preemptive buffering (LCFS/PB). They evaluate the performance tradeoffs offered by these policies, as they relate to the mean and variance of the waiting times of messages which are eventually served or eventually rejected/preempted