RealProct: Reliable Protocol Conformance Testing with Real Nodes for Wireless Sensor Networks

Despite the various applications of wireless sensor network (WSN), experiences from real WSN deployments show that protocol implementations in sensor nodes are susceptible to software failures, which may cause network failures or even breakdown. Pre-deployment protocol conformance testing is essential to ensure reliable communications for WSNs. Unfortunately, existing solutions with simulators cannot test the exact hardware and implementation environment as real sensors, whereas testbeds are expensive and limited to small scale networks and topologies. In this paper, we present RealProct, a novel and reliable framework for testing protocol implementations against their specifications in WSNs. RealProct utilizes real sensors for protocol conformance testing to ensure that the results are close to the real deployment. Using different techniques from those in simulations and real deployments, RealProct virtualizes a large network with any topology and generate non-deterministic events using only a small number of sensors to provide flexibility and to reduce the cost. The framework is carefully designed to support efficient testing in resource-limited sensors. Moreover, test execution and verdict are optimized to minimize the number of runs, while guaranteeing satisfactory false posi tive and false negative rates. We implement RealProct and test it with the IIP TCP/IP protocol stack and a routing protocol developed for WSNs in Contiki-2.4. The results demonstrate the effectiveness of RealProct by detecting several new bugs and all previously discovered bugs in various versions of the μIP TCP/IP protocol stack.