A Cross-Layer Distributed Beamforming Approach to Increase Base Station Anonymity in Wireless Sensor Networks

In most applications of wireless sensor networks (WSNs), nodes act as data sources and forward measurements to a central base station (BS) that may also perform network management tasks. The critical role of the BS makes it a target for an adversary´s attack. Even if a WSN employs conventional security primitives such as encryption and authentication, an adversary can apply traffic analysis techniques to find the BS. Therefore, the BS should be kept anonymous to protect its identity, role, and location. Previous work has demonstrated distributed beamforming to be an effective technique to boost BS anonymity in WSNs; however, the implementation of distributed beamforming requires significant coordination messaging that increases transmission activities and alerts the adversary to the possibility of deceptive activities. In this paper we present a novel, cross-layer design that exploits the integration of the control traffic of distributed beamforming with the MAC protocol in order to boost the BS anonymity while keeping the rate of node transmission at a normal rate. The advantages of our proposed approach include minimizing the overhead of anonymity measures and lowering the transmission power throughout the network which leads to increased spectrum efficiency and reduced energy consumption. The simulation results confirm the effectiveness our cross-layer design.