On the effect of sudden data bursts in the upstream channel of Ethernet PONs employing IPACT under the gated-service discipline

摘要

The Interleaved Polling with Adapted Cycle Times (IPACT) algorithm for dynamic bandwidth allocation proposed for Ethernet Passive Optical Networks (EPONs) has been deeply analysed in the literature under Poisson traffic. However, the case when ONUs suddenly offer bursty traffic in the upstream channel of a PON has not been considered in such detail. This paper studies the performance behaviour of the upstream channel of EPONs employing IPACT with the gated-service disciple, under Poisson traffic together with sudden bursts. We show that one burst arrival produces a peak in the average transmission window of every ONU, lasting its effects for several cycle times, depending on the burst size and the average network load. Such a burst has a direct impact on the delay experienced by the packets of other ONUs. This is mathematically modelled using a modification of the formerly studied M/G/1 queue with vacations and validated with simulation.