Zeroing-in on network metric minima for sink location determination

Abstract

The locations of base stations are critically important to the viability of wireless sensor networks. In this paper, we examine the location privacy problem from both the attack and defense sides. We start by examining adversaries targeting at identifying the sink location using minimum amount of resources. In particular, they launch a Zeroing-In attack leveraging the fact that several network metrics are 2-dimensional functions in the plane of the network and their values minimize at the sink. Thus, determining the sink locations is equivalent to finding the minima of those functions. We have shown that by obtaining the hop counts or the arrival time of a broadcast packet at a few spots in the network, the adversaries are able to determine the sink location with the accuracy of one radio range, sufficient to disable the sink by launching jamming attacks. To cope with the Zeroing-In attacks, we have proposed a directed-walk-based scheme and validated that the defense strategy is effective in deceiving adversaries at little energy costs.