Showing papers by "Andrzej Chydzinski published in 2013"

Scheduler for Virtualization of Links with Partial Performance Isolation

Abstract: In this paper we study a scheduler for creating several virtual links on one physical link. The scheduler provides partial isolation of the performance between the virtual links in a sense that the volume of traffic offered to one virtual link may influence the performance of other virtual links, but only up to some extent. Namely, the virtual links have guaranteed boundaries of the performance characteristics, no matter what happens with other links. Contrary to schedulers with full performance isolation, the studied scheduler is partially work conserving – some heavily loaded virtual links may benefit from the light load of other virtual links. We give a description of the scheduler, compute boundaries of its performance characteristics and present the actual performance in several simulated scenarios.

Buffer overflow period in a batch-arrival queue with autocorrelated arrivals

Abstract: In this paper a study on the buffer overflow period in a finite-b uffer queue is presented. A special attention is paid to the autocorrelation and batch arrivals, which are supposed to m imic the properties of real arrival processes. Using the bat ch Markovian arrival process, formulas for the duration of the first, subs equent and stationary overflow periods, as well as formulas f or the distribution of the number of consecutive losses during the overflow perio d are shown. Moreover, analytical results are illustrated v ia numerical examples. In particular, the influence of the autocorrelati on and batch arrivals on the duration of the overflow period is demonstrated.