A New Design for Control Method Based on Hierarchical Deficit Round Robin Scheduler for EPON

Abstract

With the development of ICT (Information and Communication Technology), how to use EPON for ensuring an effective and fair bandwidth allocation as well as the quality of service has become an important issue. Our research is based on Cousin Fair Hierarchical Deficit Round Robin Dynamic Bandwidth Allocation (CFH-DRR DBA), which applies the concepts of hierarchical scheduling to reduce extra actions in information controlling and queue switching and DRR (Deficit Round Robin) to attain the goal of cousin fairness. Our research proposes three additional modules to CFHDDR DBA: (1) an admission control module, which limits the sum weight of QoS-controlled flow; (2) a weight partition module, which isolates the sum weight of other interfering flows from QoS-controlled flows; and (3) the quantum adaptation module, which minimizes the access time of QoS-controlled flows through Quantum distribution. With the help of OMNet++ simulation software, this research presents the improvement of CFHDRR by introducing dynamic DDR Quantum. In addition, it proposes admission control and bounded weight to keep the sum of flows within service capacity. The simulation result shows that, while keeping CFHDRR's fairness, the queuing delay is reduced and the cycle time is effectively controlled so that the packet delay of QoS-controlled flows is minimized and QoS of real-time multimedia in EPON is fairly ensured.