Physical Layer Authentication in Line-of-Sight Underwater Acoustic Sensor Networks

Physical layer authentication scheme for sensor node authentication using location-specific feature i.e. Angle of Arrival (azimuth, elevation) in an underwater environment is proposed. Under the “Alice-Bob-Eve” scenario, the sink node (Alice) maintains a database of the estimated angle of arrivals. The authentication process includes the comparison of measured AoA against the database based on Mahalanobis distance. The distributions of genuine and malicious sensor node Mahalanobis distance measures are modeled as finite Gaussian Mixture Model (GMM). This work considers a static, line-of-sight underwater acoustic sensor network (UASN). The performance of the proposed scheme is expressed by the Probability of Detection (PD) and the Probability of False Alarm (PFA) which shows a very good trade-off.