Location Privacy in Unattended Wireless Sensor Networks upon the Requirement of Data Survivability

Wireless sensor networks have been used recently to obtain forensic evidence. One of the basic principles of obtaining forensic evidence is to maintain the integrity of the evidence. To increase the probability of retaining data integrity, the data replication strategy was proposed for unattended wireless sensor networks (UWSN), wherein the data integrity was quantified by data survival rate. However, the distribution of multiple data replicas may expose the location information of some critical nodes, thereby resulting in a high possibility of being attacked by the adversary. In this paper, we study the trade-off between the data survival rate and the location privacy of a critical node in an UWSN. Obviously, the increase in the number of data replicas can improve the data survival rate, but could severely degrade the location privacy of a critical node. Based on the captured data replicas, we propose three location estimation algorithms, the coordinate median, average of overlapping area and expectation-maximization approaches. The location estimation performance of the proposed schemes is evaluated and the trade-off between the data survival rate are investigated. According to the simulation results, the location privacy degrades severely with the increase in the number of data replicas.