Power-Efficient Direct-Voting Assurance for Data Fusion in Wireless Sensor Networks

Data fusion, in which collected data are fused before they are sent to the base station, is usually implemented over the wireless sensor network. Since a sensor is typically placed in locations that are accessible to malicious attackers, information assurance of the data fusion process is very important. A witness-based approach has been proposed to verify the fusion data. In this approach, the base station receives the fusion data and ``votes'' on the data from a randomly chosen sensor node. The vote comes from other sensor nodes, called ``witnesses,'' to confirm the correctness of the fusion data. Since the base station receives the vote through the chosen node, this node could forge the vote if it is compromised.. This work improves the witness-based approach using a direct voting mechanism, such that the proposed scheme performs better in terms of assurance, overhead and delay. The witness node transmits the vote directly to the base station. Forgery does not pose a problem in this scheme. Moreover, fewer bits are necessary to represent the vote, significantly reducing the power consumption. Performance analysis and simulation results indicate that the proposed approach has a 40-times lower overhead than the witness-based approach.