Distributed dynamic channel access scheduling in large WMN systems

Wireless mesh networks (WMNs) suffer from scalability, performance degradation and service disruption issues due to overwhelming multi-hop co-channel interference, unscrupulous channel utilization and inherent network mobility. We propose a set of efficient distributed dynamic channel access scheduling protocols, called DDCS, based on distributed clustering and dynamic Latin squares for WMN systems with multi-radio multi-channel (MRMC) communication capabilities. DDCS uses nodal interference information to form cliques for inter-cluster and intra-cluster structures in WMNs, and then applies Latin squares to map the clique-based clustering results to radios and channels for wireless communication purposes. Afterwards, DDCS again applies Latin squares to schedule the channel access amongst nodes within each cluster in a collision-free manner. A coexistence mechanism for DDCS and widely used IEEE 802.11 DCF is also addressed in this paper, so that our MRMC access protocol DDCS can be effectively applied in large-scale WMNs. The evaluation results show that DDCS achieves much better performance than existing IEEE 802.11 standards and other multi-channel access control protocols.