Research Of Network Coding-aware Routing Algorithm In Wireless Networks

Wireless networks can be used for wireless communication, monitoring environment, data collection and others. However, the nodes in wireless networks have the limited capacity of energy, storage, communication, computing and others. The intermediate nodes in traditional wireless routings only have the ability for store-forwarding data, the function of this mode is confined, we can't solve the problem of low throughput in networks. Network coding allows intermediate nodes responsible for computing and processing data, so it can greatly breakthrough the weakness of traditional routing protocols. Positive network coding algorithms——routing-aware algorithm can activly find coding opportunities, further improve the network throughput. With the development of network coding, the research of coding-aware routing protocols has also launched, it's a big challenge to design an appropriate multi-hop wireless network protocol by using coding-aware routing algorithm.Firstly, this paper describes the traditional wireless network routing protocols, Then a simple analysis of routing protocols using network coding in recent years. To solve the problems of network coding protocols which passively waiting opportunities, many researchers dedicated to design coding-aware routings. One of the importances is designing a suitable metric. In this paper, we propose two different algorithms to improve the inadequacies of existing coding-aware routing mechanisms, then use our metrics to make coding algorithm more efficient in actual wireless networks.Existing research on network coding-aware neglects the energy problem. As the large impact of energy performance in wireless network, it's important to considering both energy and coding opportunities, designing a metric to prolong network lifetime. This paper firstly proposes a metric based on coding-opportunity and energy, using this metric to design a routing protocol ECAR (Energy-based Coding-aware Routing). We use Matlab as simulation tool, the experiment results indicate that this method can decrease energy consumption, balance traffic load, prolong network lifetime.Coding-aware routing protocols can greatly improve the efficiency of network coding, however, used in 802.11 wireless network environment, we need to consider more about multi-rate and other practical problems. secondly, considering with rate optimization, we propse a Rate-selected-based Distributed Coding-aware Routing. This Routing protocol can select the appropriate transmission rate and encoding scheme to the different SNR(Signal to Noise Ratio)s of the networks. Matlab simulation results show, compared to traditional network coding routing protocols, this method can increase opportunities and improve the network throughput.