Building Responsive Systems from Physically-correct Speciications
نویسنده
چکیده
Predictability { the ability to foretell that an implementation will not violate a set of speciied reliability and timeliness requirements { is a crucial, highly desirable property of responsive embedded systems. This paper overviews a development methodology for responsive systems, which enhances predictability by eliminating potential hazards resulting from physically-unsound speciications. The backbone of our methodology is the Time-constrained Reactive Automaton (TRA) formalism, which adopts a fundamental notion of space and time that restricts expressiveness in a way that allows the speciication of only reactive, spontaneous, and causal computation. Using the TRA model, unrealistic systems { possessing properties such as clairvoyance, caprice, innnite capacity, or perfect timing { cannot even be speciied. We argue that this \ounce of prevention" at the speciication level is likely to spare a lot of time and energy in the development cycle of responsive systems { not to mention the elimination of potential hazards that would have gone, otherwise, unnoticed. The TRA model is presented to system developers through the CLEOPATRA programming language. CLEOPATRA features a C-like imperative syntax for the description of computation, which makes it easier to incorporate in applications already using C. It is event-driven, and thus appropriate for embedded process control applications. It is object-oriented and compositional, thus advocating modularity and reusability. CLEOPATRA is semantically sound; its objects can be transformed, mechanically and unambiguously, into formal TRA automata for veriication purposes , which can be pursued using model-checking or theorem proving techniques. Since 1989, an ancestor of CLEOPATRA has been in use as a speciication and simulation language for embedded time-critical robotic processes.
منابع مشابه
An Ounce of Prevention Is worth a Pound of Cure towards Physically-correct Speciications of Embedded Real-time Systems
Predictability { the ability to foretell that an implementation will not violate a set of speciied reliability and timeliness requirements { is a crucial, highly desirable property of responsive embedded systems. This paper overviews a development methodology for responsive systems, which enhances predictability by eliminating potential hazards resulting from physically-unsound speciications. T...
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