01085nas a2200145   4500000000100000000000100001008004100002260001200043100001600055700002400071700001600095245012100111490000700232520070000239       2021                            d  c07/20211 aTomasz Nycz1 aTadeusz Czachórski1 aMonika Nycz00aDiffusion Model of Preemptive-Resume Priority Systems and Its Application to Performance Evaluation of SDN Switches.0 v213 a<p>The increasing use of Software-Defined Networks brings the need for their performance analysis and detailed analytical and numerical models of them. The primary element of such research is a model of a SDN switch. This model should take into account non-Poisson traffic and general distributions of service times. Because of frequent changes in SDN flows, it should also analyze transient states of the queues. The method of diffusion approximation can meet these requirements. We present here a diffusion approximation of priority queues and apply it to build a more detailed model of SDN switch where packets returned by the central controller have higher priority than other packets.</p>