Reverse engineering and visualization of the reactive behavior of PLC applications

This paper presents an approach to reverse engineering and dynamic analysis of the reactive behavior of PLC programs. Based on execution traces, it is shown how to derive a state model representation of the reactive program behavior and how this model supports dynamic program analysis. In particular, the state model is used for mining execution patterns which occur repeatedly in a program execution. We discuss the key ideas of the approach, the various analysis and visualization methods available, and results from a case study.