A Sort-Based DBA Algorithm for EPON System

EPON technology is being considered as a promising solution for next-generation broadband access network due to the convergence of low-cost equipments. To prevent data collision and ensure efficient transmission, a MAC protocol to share resource of upstream transmission medium is necessary. This article proposes a sort-based DBA algorithm that sorts all REPORT messages by length to fully utilize the idle time as long as at least one ONU requests a long enough transmission window; or some requests be lain out together in idle period to compensate the idle time when no request length is long enough. Besides, a queue management scheme also be developed, which improves efficiency further by decreasing the overhead of REPORT messages when the ONU queue is long. Event-driven simulations show that sort-based DBA can improve network performance in terms of packet delay, average queue length and throughput, as compared with the well-known IPACT and DBA2 algorithms.