Distributed Randomized Algorithm based on Buffer Utility for Control Channel Scheduling in IEEE 802.16 Mesh Networks

Coordinated distributed scheduling (CDS) is defined in IEEE 802.16 mesh mode, which is a scheduling method serves communications between nodes without connecting to Internet. The analysis on CDS shows that the algorithm CDS adapted cannot satisfy QoS requirement entirely. In this paper, a new distributed randomized scheduling algorithm based on buffer utility (RBU-CDS) is proposed to cut down end to end delay and improve the throughput of the network. An idea from game with incomplete information is introduced to calculate the competitive ranking of competing nodes in RBU-CDS. The competitive ranking of a node is estimated based on the joint distribution of buffer utilities of competing nodes, only the current node’s buffer utility must be got with cross-lay method. The node with higher competitive ranking will be scheduled earlier. The buffer utility of node with higher traffic load is normally higher. For higher buffer utility can lead to higher competitive ranking estimated, node with higher traffic load will be scheduled earlier in RBU-CDS. As a result, the resource utilization will be promoted and the possibility of occurrence of congestion decreased. Simulation results show that the proposed algorithm reduces end to end delay and improves network throughput.