Throughput optimality of single queue priority schemes

The throughput optimality ofpriority management strategies in a single buffer has been studiedfor a general aggregate arrival law. The tight upper bounds found are useful to understand optimality in utilization of specijic priority schemes such as push-out buffer (POB) and partial buffer sharing (PBS). This paper further focuses on the maximum allowable load pmaa versus the priority mix a for a PBS and a random push-out buffer (R POB) of size I( for a wide variety of arrival processes. The role of priorities in a special type of bursty arrivals, the compound Poisson process with constant burst length and random priority assignment within the burst, is found to be less pronounced than that of 'pure' Poisson arrivals. On the other hand, the results for ONOFF cell arrivals modeled by a MMPP(2), MMPP(3), and higher order Markov Modulated Processes closely follow the behaviour of the maximum allowable load in the R POB with Poisson arrivals, howevel; scaled to lower loads. The results indicate that the priority mix distribution within the aggregate arrival flow influences the shape of pmaz(a)curve more than the aggregate arrival distribution itsev