Event-Driven Visual Sensor Networks: Issues in Reliability

Event-driven visual sensor networks (VSNs) rely on a combination of camera nodes and scalar sensors to determine if a frame contains an event of interest that should be transmitted to the cluster head. The appeal of event-driven VSNs stems from the possibility of eliminating non-relevant frames at the source thus implicitly minimizing the amount of energy required for coding and transmission. The challenges of the event-driven paradigm result from the vulnerability of scalar sensors to attack or error and from the lightweight image processing available to the camera nodes due to resource constraints. In this work we focus on the reliability issues of VSNs in the case of global actuation attacks on the scalar sensors. We study the extent to which various utility functions enable an attacker to increase the average expected number of affected nodes with a relatively small penalty in the loss of stealth. We then discuss tradeoffs between different attack detection strategies in terms of the cost of processing and the required information at the cluster head and nodes.