Optimization of Multicast End-to-End Delay in Multi-Radio Wireless Mesh Networks

Multi-radio wireless mesh network (MR-WMN) is one of the key access techniques in Mobile Internet. However, current 802.11-based MR-WMN is not able to provide low multicast end-to-end delay. To address this problem, we first propose a layered and analytical model by combining overlapping channel assignment with multi-path routing strategies. The proposed model can be used as a guide on multicast design. It decoupled multicast delay into transmission delay in the MAC layer and queuing delay in the Mesh layer based on that it derived a new multicast routing metric that had low end-to-end delay. Second, we prove that finding the minimum global flow interference solution is a NP-Complete problem an<I the relationship between global flow interference and network node densities is distributed in accord with double-Pareto lognormal (dP1N) distribution. Based on these two results, the DCA algorithm is proposed in order to minimum global flow interference which can efficiently reduce the multicast transmission delay in MAC layer. Last, to avoid the best wireless link being congested, we propose the flow adaptive-based MMRA algorithm by making use of the M R-M ED routing metric and the multi-path routing design philosophy, which took local channel congestion into account and can efficiently reduce the queuing delay in Mesh layer. Simulation result and comparison of the common algorithm MCM both show that the proposed model accurately characterizes the multicast delay in multi-radio wireless mesh network and the combination of the DCA and MMRA algorithms efficiently reduce the multicast end-to-end delay.