A New Hybrid SPD-Based Scheduling for EPONs
Dynamic Bandwidth Allocation (DBA) is a key issue of Ethernet PONs. In order to get higher resource utilization and lower packet delay, the problem is always dissolved into grant sizing and grant scheduling. In this paper, the authors explore grant scheduling techniques. They propose a modified Hybrid online and offline scheduling with the Shortest Propagation Delay (SPD) first policy (they named HSPD) which can compensate for the idle time under light or medium loaded traffic. Meanwhile, the Last ONU in offline set is adaptively indicated to transmit REPORT Frame first (called LRF), so the idle time can be eliminated especially under heavy loaded traffic.