Requirements-based testing of real-time systems: Modeling for testability

Requirements validation depends largely on the techniques used for specification, so the augmented finite-state machine (FSM) model used to capture the external behavior of a real-time system is central to the environment. Therefore, this paper describes the validation techniques used and explores those aspects of the specification model that facilitate test generation and execution using the behavioral description. We refer to this theme as requirements modeling for testability. Our thesis is: although an FSM or an augmented FSM may be relatively limited in its ability to capture the whole range of practical systems´ behaviors, it is adequate for real-time systems in which sequential computations dominate. The FSM model should be preferred for applications in which high reliability is a primary concern; expressive power can be traded off to ensure quality.