Analyzing and modeling the failure behavior of Wireless Sensor Networks software under errors

As Wireless Sensor Networks (WSNs) are starting to be adopted in critical scenarios, it becomes important to study the behavior of WSN software in response to errors induced by hardware faults. To this aim, in this paper we present the results of an extensive fault-injection campaign, conducted on three different WSN operating systems (OSs). Results show that, depending on the concurrency model and on the memory management, the OS reacts to injected faults differently, indicating that fault containment strategies and hang-checking assertions should be implemented to avoid spreading and activations of errors. Analysis also allowed us to define a detailed dependability model of the WSN software, to be used to simulate the expected failure behavior of a given OS when solicited by given low-level hardware faults.