Efficient Network Coding-Based Loss Recovery for Reliable Multicast in Wireless Networks

Recently, network coding has been applied to the loss recovery of reliable multicast in wireless networks [19]. where multiple lost packets ate XOR-ed together as one packet and forwarded via single re-transmission resulting in a significant reduction of bandwidth consumption In this paper. we first prove that maximizing the number of lost packets for XOR-ing. which is the key part of the available network coding-based reliable multicast schemes. is actually a complex NP-complete problem To address this limitation. we then propose an efficient heuristic algorithm for finding an approximately optimal solution of this optimization problem Furthermore, we show that the packet coding principle of maximizing the number of lost packets for XOR-ing sometimes cannot fully exploit the potential coding opportunities. and we then further propose new heuristic-based schemes with a new coding principle Simulation results demonstrate that the heuristic-based schemes have very low computational complexity and can achieve almost the same transmission efficiency as the current coding-based high-complexity schemes Furthermore the heuristic-based schemes with the new coding principle not only have very low complexity. but also slightly outperform the curt em high-complexity ones