A class-based dynamic bandwidth allocation scheme for EPONs

In an Ethernet passive optical network (EPON), all optical network units (ONUs) share one uplink channel to transmit multiple traffic. To avoid data collision, a contention-free MAC protocol is needed to schedule the transmission order of different ONUs. An available solution is to assign a variable-sized time slot to each ONU. In this paper, we first review some existing bandwidth allocation schemes for EPON in the literature. Then we propose a novel scheme called dynamic weight priority scheduling (DWPS), which not only guarantees all the ONUs that fairly share the bandwidth of uplink channel on demand, but also supports differentiated services. To prevent one service class from monopolizing the bandwidth under heavy load, a bandwidth threshold determined by a weight ensures a minimum bandwidth for each traffic class