Global property violation detection and diagnosis for wireless sensor networks

Run-time error detection and deterministic off-line error replay have received wide attention in recent years as a technique to enhance the programmer's ability to find software errors. To apply this technique to wireless sensor networks (WSN), one must be able to deal with the severe constraint on the memory, the communication bandwidth and the energy source on the sensor motes and the highly dynamic and unpredictable operating environment. All these make it difficult for the application programmer to manually insert operations required for error detection and replay. This paper makes three contributions towards making error detection and replay automatic for WSNs: (i) a domain-specific language, called SensorC, for specifying WSN global properties that must be satisfied when the system and its application software are deployed; (ii) a method to automatically decompose such global properties into a set of local operations to detect global property violations, with the goal to minimize the communication traffic for state information exchanges; and (iii) a new program analysis to identify program sub-traces that can be skipped for replay without losing the accuracy of diagnosis. The proposed techniques, which are implemented in a compiler, are shown by experiments to successfully catch real WSN software errors and to substantially reduce message exchanges for run time error detection.