Protecting Location Privacy in Large-Scale Wireless Sensor Networks

In a wireless sensor network, an adversary equipped monitoring antenna can easily overhear packets, which may facilitate identifying the directions of packet flows and trace to the sink or source nodes. In order to defend the location privacy of the sink and source nodes, we propose a location privacy support scheme (LPSS). We prove that, with the increase in distance between sink and source node, the protection strength of the LPSS increases exponentially. Theoretical and simulation results show that LPSS can provide strong location privacy protection for both the sink and source nodes under different attacks. Under the similar delivery delay (or energy consumption), the safe time provided by LPSS is much longer than other approaches. Facilitated by the study on LPSS, we further investigate that the correlation between sink and source nodes. We find that if one source node is exposed to a sophisticated adversary, conventional fake packet injection mechanisms for protecting sink node tend to be useless.