A Packet-based Load Balancing Scheme for Network Coding in Tactical Heterogeneous Wireless Networks

Network coding has been proven to be an effective technique to increase the throughput and enhance robustness of various wireless networks including tactical heterogeneous wireless networks. Usually, the tactical heterogeneous wireless networks consist of different wireless links including high bandwidth links like IEEE 802.11 and low bandwidth links like UHF and VHF. Load balancing is an effective way to mitigate the network loading and improve overall performance of heterogeneous network. Traditional flow-based load balancing scheme performs poor and has a negative effect when applying network coding in tactical heterogeneous wireless networks. How to enhance the performance of network coding over tactical heterogeneous network is worthy of research. In this paper, with full consideration of different channel propagation characteristics and distinct transmission demands of different packets in a single stream, we propose a packet based load balancing scheme, making appropriate use of highly unbalanced links by transmitting different types of packets on different channels. By making full use of the propagation characteristics of low bandwidth channels, our scheme can significantly shorten the end to end delay of feedback packets and improve the transmission reliability of feedback packets. Compared with flow -based load balancing, our scheme can reduce 63.47% of the redundant transmissions on average and achieve 15.53% improvement of throughput.