Many dependable systems rely implicitly on the integrity of the positions of their components. For example, let us consider a sensor network for pollution monitoring: it is sufficient that a hostile actor physically moves some sensors to completely disrupt the monitoring. In such scenarios, a key question is: how to securely verify the positions of devices? To answer this question, researchers proposed several solutions. However, these generally require several fixed stations (anchors) with trusted positions. In this paper, we explore the possibility to use the emerging drone technology in order to overcome the limitation of using several fixed anchors.
In particular, our approach is to replace all the fixed anchors with a single drone that flies through a sequence of waypoints. At each waypoint, the drone “acts like” an anchor and securely verifies the positions of the devices. The main challenge here is to find a convenient path for the drone to do this. The problem presents novel aspects, thus existing path planning algorithms cannot be used. We present VerifierBee: a path planning algorithm that allows a drone to perform a secure location verification of a set of devices. VerifierBee finds a good approximation of the shortest path, and at the same time it respects a set of requirements about drone controllability, localization precision, and communication range.