Opportunistic routing for multiple multicast flows in wireless mesh networks

Opportunistic routing (OR) involves multiple candidate forwarders to relay packets by taking advantage of the broadcast nature and multi-user diversity of the wireless medium. OR combats lossy wireless transmissions in comparison with traditional routing (TR) in which only one pre-selected next-hop node is involved to forward packets. At present, the OR does not take account of the traffic load, therefore some nodes may be overloaded while the others may not, leading to network performance decline. The OR for multiple multicast flows is described as a convex optimisation problem. In order to solve the problem, by combining primal-dual and subgradient methods, a fully distributed joint candidate forwarder selection Opportunities Routing for Multiple Multicast Flows algorithm (ORMMcF) is proposed. ORMMcF allocates the flow rate iteratively and the rate allocation decides the candidate forwarder selection of opportunistic routing. The simulation results show that ORMMcF algorithm improves 46.2%, 29.2% of the aggregative throughput than ETX and EAX, respectively.