Performance Study of Homogeneous Uplink Scheduling in Hybrid ONU-BS Architecture

The integration of Ethernet Passive Optical Network (EPON) and Worldwide Interoperability for Microwave Access (WiMAX) is regarded as a promising access solution in realizing fixed mobile convergence (FMC) networks, which uses a single network infrastructure to provide both wired and wireless access services, and a good match of capacity hierarchy between EPON and WiMAX by using EPON as a backhaul (or feeder) to connect multiple disperse WiMAX base stations. Furthermore, the Hybrid ONU-BS Architecture (HOA), which can not only bring economic efficiency to network providers but also supporting better quality of service (QoS) and bandwidth utilization. A critical part of the HOA is packet scheduling, which resolves contention for bandwidth and determines the transmission order of users. For successful realizing HOA deployment, evaluating the performance of packet scheduling algorithms is one of the most importance issues. In this paper, we accomplish a comprehensive performance study of homogeneous uplink scheduling algorithms in HOA. Firstly, we make a classification of queuing scheduling algorithms in MAC layer packet forwarding mode, then simulate in view of a representative number of algorithms and investigate fundamental characteristics in each class of HOA. We evaluate the packet forwarding algorithms abilities for the multiple classes of service, providing QoS guarantees, fairness amongst service classes, blocking probability rate and bandwidth utilization. To the best of our knowledge, no such comprehensive performance study has been reported in the literature. Simulation results demonstrate that none of the current algorithms is capable of effectively supporting all classes of service. We hope that this study will interest readers and stimulate further investigation in the area. KeywordsEPON; WiMAX; FMC; ONU-BS; HOA; packet scheduling.