Adaptive dynamic bandwidth allocation algorithm with sorting report messages for ethernet passive optical network

Broadband access networks using passive optical network (PON) technology can extend the transmission distance and increase the transmission capacity of carrier networks. One PON solution, the Ethernet passive optical network (EPON), can provide huge bandwidth capacity, low cost, simple architecture and easy maintenance. Therefore EPON becomes a promising candidate for future last-mile solutions. To prevent data collision and ensure efficient transmission, EPON must employ a media access control (MAC) protocol to allocate the shared resource of a common upstream transmission medium. This article proposes a novel DBA algorithm that sorts all REPORT messages by the request length at the next transmission cycle to fully utilise the idle time between cycles as long as at least one optical network unit (ONU) requests a long enough transmission window. Alternately, when no grant length is long enough, then some of ONUs' requests are laid out together in the idle period to utilise the otherwise wasted idle time. Event-driven simulations show that Sort-DBA can significantly improve the network performance in terms of packet delay, average queue length and throughput, as compared with the well known IPACT, DBA2 and scheduling control scheme DBA algorithms.