A user authentication-based probabilistic risk approach for Wireless Sensor Networks

Sensor nodes are low power devices which have limited computing resources. For various sensor network applications, providing a variety of security functions with limited energy resources and low power capabilities is a very big challenge. Recently, Vaidya et al. proposed an Improved Robust Dynamic User Authentication Scheme for Wireless Sensor Networks (WSNs) that allows legitimate users to query sensor data at every sensor node of the network. In this work, we show that, Vaidya et al.´s scheme suffers from the risk of forgery attacks and Denial-of-Service (DoS) attacks. To cope with them, we propose a new solution which is quite adequate for power and resource constrained sensor networks. The proposed scheme not only retains all the advantages in Vaidya et al.´s scheme but also protects against DoS and forgery attacks. After an evaluation of the energy cost based on the computational complexity, we use in our implementation the probability risk analysis owing to the DoS attack model to show to which level the proposed solution justifies the better energy consumption for a given network architecture.