On channel assignment and multicast routing in multi–channel multi–radio wireless mesh networks

Abstract: Multicast is a key networking service, enabling one-shot delivery of information from a source to multiple destinations and is considered underlying for collaborating multimedia applications such as video conferencing, distance learning and other forms of content distributing over Multi-Channel Multi-Radio Wireless Mesh Networks (MCMR WMNs). Multicast protocol as designed in these networks, however, is tightly coupled with the specifics of the nodes’ channel-radio associations to realise minimum interference communication. The mainstream of research in WMN multicasting is oriented towards heuristic or meta-heuristic strategies which basically take on a sequential approach to solve the channel assignment and the multicast routing as two disjoint sub-problems. The resulting network configurations would be sub-optimal in this case. It is given that the cross-interaction between the two sub-problems is an effect of the problem’s specifications. In this paper, first, we propose a cross-layer mathematical formulation of joint channel assignment and multicast tree construction in MCMR WMNs, which, opposed to the existing schemes guarantees optimal solution. The simulation results demonstrate that our cross-layer design outperforms the Level Channel Assignment (LCA), Multi-Channel Multicast (MCM), the Genetic Algorithm (GA), Simulated Annealing (SA) and the Tabu Searc