Group colloquium: Model-Based Testing for General Stochastic Time

When: April 5, 2018, 15:45-16:45

Where: RA 3336

Who: Marcus Gerhold

Many systems are inherently stochastic: they interact with unpredictable environments or use randomised algorithms. Then classical model-based testing is insufficient: it only covers functional correctness. We present a new model-based testing framework that additionally covers the stochastic aspects in hard and soft real-time systems. Using the theory of stochastic automata for specifications, test cases and a formal notion of conformance, it provides clean mechanisms to represent underspecification, randomisation, and stochastic timing. Supporting arbitrary continuous and discrete probability distributions, the framework generalises previous work based on purely Markovian models. We cleanly define its theoretical foundations, and then outline a practical algorithm for statistical conformance testing based on the Kolmogorov-Smirnov test. We exemplify the framework's capabilities and tradeoffs by testing timing aspects of the Bluetooth device discovery protocol. This is joint work with Arnd Hartmanns and Mariëlle Stoelinga, to be presented at the 2018 NASA Formal Methods Symposium.