With the proliferation of high-end mobile devices that feature wireless interfaces

many practical applications are enabled in opportunistic networks which comprise mobile devices.Contrary to the traditional networks

opportunistic networks utilize the mobility of nodes to relay messages based on the store-carry-forward paradigm.We propose an efficient P2P query algorithm based on betweenness centrality forwarding (PQBCF) for opportunistic networking

which adopts the metric of betweenness centrality from social network analysis to estimate the active degree of nodes in the networks.PQBCF leverages nodes with greater betweenness centrality as relays to increase query success rate and reduce query latency.Simulation results demonstrate that PQBCF outperforms most state-of-the-art algorithms and achieves approximate efficiency as epidemic with much less resource consumption.