On protecting end-to-end location privacy against local eavesdropper in wireless sensor networks

Wireless Sensor Networks (WSNs) are often deployed in hostile environments to detect and collect interested events such as the appearance of a rare animal, which is called event collection system. However, due to the open characteristic of wireless communications, an adversary can detect the location of a source or sink and eventually capture them by eavesdropping on the sensor nodes' transmissions and tracing the packets' trajectories in the networks. Thus the location privacy of both the source and sink becomes a critical issue in WSNs. Previous research only focuses on the location privacy of the source or sink independently. In this paper, we address the importance of location privacy of both the source and sink and propose four schemes called forward random walk (FRW), bidirectional tree (BT), dynamic bidirectional tree (DBT) and zigzag bidirectional tree (ZBT) respectively to deliver messages from source to sink, which can protect the end-to-end location privacy against local eavesdropper. Simulation results illustrate the effectiveness of the proposed location privacy protection schemes.