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Hierarchical Model Exploration for Exposing Off-nominal Behaviors

Finding and addressing off-nominal behaviors in the later phases of the software development life cycle is costly and time consuming. In our previous work, we proposed the causal component model (CCM), a semi-automated approach that can expose off-nominal behaviors in requirements. The empirical study with CCM showed promising results, but CCM has limitations with scalability. To reduce the scalability issues, in particular because of hierarchical relationships, we propose an enhanced causal component model that uses hierarchical model exploration. The results of our case study indicate that the proposed approach reduces the state/rule explosion problem and detects off-nominal behaviors.