Adaptive Threshold Determining Method for Statistical Filtering Scheme in Sensor Networks

Sungkyunkwan University, Suwon 440-740, South Korea Summary Many sensor network applications are dependent on the secure operation of networks, and will have serious outcome if the network is disrupted or injured. Bogus reports can be injected through the compromised nodes, which can lead to not only false alarms but also the depletion of limited energy resource. Ye et al. proposed a statistical en-route filtering scheme (SEF) to detect such bogus reports during the forwarding process. In SEF, it is important that determining a number of the message authentication code (MAC) which will be attached in event report when a real event occurs since it trades off detection power and overhead. This paper presents an adaptive threshold determining method for energy saving based on distance. Sensor field is divided into several areas by considering the distance from the base station. Each area uses the different number of the MACs so that the size of report can be reduced by the distance between the base station and the region where event occurs in hop count. Thus, we can reduce the energy consumption in transmitting.