Abstract:Opportunistic networks utilize the contact opportunities created by node movement to forward data between node pairs. Data is piggybacked during its carrier's movement, which guarantees node independence while imposes an impact on data transmission performance. This study designs a routing algorithm for opportunistic networks based on node movement characters. Considering the factors of data transmission, data content and application demands, a data forwarding priority evaluation model is developed and adopted to determine the data transmission rules combined with the division of node activity range. The transfer strategy of differential message replicas is proposed to achieve a tradeoff between transmission efficiency and system overhead. A node free motion degree function is constructed according to activity range distribution, centrality degree, and energy level to evaluate the node motion level. And then a utility function is deduced for relaying node selection. The simulation results demonstrate that the proposed algorithm achieves higher packet delivery ratio and less delivery latency while satisfying application demands and restraining network overhead.