A packet authentication scheme for wireless sensor networks

Securing Wireless Sensor Networks (WSNs) against attacks is crucial in order to deploy them across a broad range of applications. It is easy for adversaries to launch sophisticated attacks against them such as wormhole, man-in-the-middle and Denial of Service (DoS), or to impersonate other sensors and send false information. We present a new packet authentication scheme that defends against attacks from unauthorized nodes external to the WSN. We also provide a framework for dynamically excluding any internal nodes that are found to be compromised. We do this by authenticating every packet at every hop using an efficient two key based system, and dropping any unauthentic packets. We evaluated the performance of our scheme and compared it with other schemes using simulations. Our scheme is found to be very efficient in terms of memory, CPU power, latency and bandwidth making it suitable for use in resource constrained wireless sensors.