In this paper, we consider extensions of state machines with additional functionality. We analyze how typical safety or liveness properties are affected when extending or refining the model. We identify several classes of extensions where properties are preserved. The extensions include adding new transitions at a state, refining transitions, as well as adding failure cases and adding additional, new functionality. We propose new concepts for refinements based on elimination of added behavior with context to capture property-preserving extensions in a precise and mostly syntactic way.
['Christian Prehofer']
Property Preservation for Extension Patterns of State Transition Diagrams