Research On Code-aware Opportunistic Routing Protocol In Wireless Networks

Network coding technology takes advantage of the correlation between data packets,allows intermediate nodes of the network to combine data packets and forward them,breaks the traditional "store-and-forward" mode and effectively improves the validity of data transmission.In traditional routing protocols,nodes can only passively obtain coding opportunities and the path is single and fixed.However,the proposal of opportunistic routing breaks the limitation and allows nodes to select multiple alternative nodes for cooperative forwarding,which effectively improves the reliability of data transmission.Code-aware routing combines the advantages of these two technologies and is one of the hot spots of current wireless network routing strategy research.The main work of this thesis is as follows:For the problem of high routing cost caused by one-sided use of traditional ondemand routing multi-hop coding structure in opportunistic coding-aware routing,an efficient opportunistic coding-aware routing protocol is proposed.This protocol firstly defines the virtual multi-hop coding conditions which is suitable for opportunistic routing characteristics to reduce routing cost.In addition,the routing metric design comprehensively considers node load,coding opportunities and residual energy,and introduces a fuzzy logic system to determine the weight of each routing factor to accommodate wireless network time variability.The simulation results indicate that the protocol proposed can effectively improve the network coding rate,network throughput and survival time compared with code-aware routing protocols based on fuzzy logic systems and extreme chance routing protocols.For the uncertainty of opportunistic routing and forwarding,a new candidate nodeset selection algorithm is designed to control the data transmission path and fluctuation range of the optimal path.In addition,considering the packet size matching,the network local load and the encoding opportunity,the encoding packet selection algorithm and candidate node-set forwarding algorithm are designed to solve the problem of increasing routing cost caused by one-sided pursuit of encoding gain.The simulation results indicate that the protocol proposed has the lower end-to-end transfer times and the higher throughput compared with coding opportunity entity protocols and opportunistic codingaware routing mechanisms.