Software Proactive Reengineering for System Resilience to Misuse

Often a perfectly functioning software system is misused causing undesirable and expensive consequences. The quest of this work is to prepare a priori the system for eventual extensions that - while not directly relevant to the system purpose - enable overcoming the consequences of its misuse to achieve system resilience. This is attained by means of Software Proactive Reengineering based upon domain knowledge to model the system misuse, beyond the original system model. In particular, if the behaviors of such a system have been modeled by statechart and problem frame approach diagrams, these diagrams can be reengineered to suitably extend them, in order to correct the misuse consequences. In this paper the approach has been demonstrated by case studies related to Signal Traffic Lights and their controllers. Specifically we refer to regular pedestrians misusing devices designed for the visually impaired.