Reducing Multicast Redundancy and Latency in Multi-Interface Multi-Channel Wireless Mesh Networks

In wireless mesh networks, each node can be equipped with multiple network interface cards tuned to different channels. In this paper, we study the problem of collision-free multicast in multi-interface multi-channel wireless mesh networks. The concept of interface redundancy is proposed as a new criterion for the multicast/broadcast redundancy in wireless mesh networks, and we prove that building a multicast/broadcast tree with the minimum interface redundancy is NP-hard. We also prove that the minimum-latency multicasting problem in multi-channel wireless mesh networks is NP-hard. We present two heuristic-based algorithms which jointly reduce the interface redundancy and the multicast latency. Since broadcast can be considered as a special case of multicast, an approximate algorithm for low-redundancy broadcast tree construction is also proposed, which has a constant approximation ratio. Finally, the simulation results prove the effectiveness of our approach.