Specification Modeling Methodologies for Reactive System

The goal of this paper is to investigate the state-of-the-art in specification-modeling methodologies applicable to reactive-system design. By combining the specification requirements of a reactive system and the desirable characteristics of a specification-modeling methodology, we develop a unified framework for evaluating any specification-modeling methodology applicable to reactive-system design. A unified framework allows the designer to look at the spectrum of choices available and quickly comprehend the suitability of a methodology to the specific application. Using the unified framework, we study a number of representative methodologies, identifying their respective strengths and weaknesses when evaluated for the desired characteristics. The differences and relationships between the various methodologies is highlighted. We find our framework to be quite useful in evaluating each methodology. A summary of our observations is presented, together with recommendations for areas needing further research in specification modeling for reactive systems. Two such areas are improving model continuity and providing better complexity control, especially across different abstraction levels and modeling domains. We also present a description of each methodology studied in the unified framework.