Device-based secure two-way ranging and node identification for wireless sensor networks

A fundamental problem when locating sensors in a network is to estimate the distance between pairs of sensors. Since security of sensor networks is vulnerable in the wireless environment, this paper proposes a secure ranging scheme which can provide secure position information for wireless sensor applications. By generalizing the asynchronous distance estimation technology (Distance Estimation via Asynchronous Clocks; DEVAC), a secure asynchronous distance estimation method (Secure Distance Estimation via Asynchronous Clocks; SDEVAC) is presented. Based on the physical property of a device, the communication delay (for instance: internal component delay, difference of the clocks, and the sensor waiting time) between two wireless sensors may be used to identify the normal wireless sensors, to renew the network node information, and to enhance the reliability of distance estimation. The method is shown to be feasible for identifying malicious sensor nodes in the network.