Showing papers presented at "Formal Methods for Industrial Critical Systems in 1999"

Questions and Answers About Ten Formal Methods

Abstract: An abstract model of an industrial distributed data base application has been studied using process based, state based, and queueing theory based methods. The methods supported by graphical notations and/or integrated development environments were found to be easiest to work with. The methods supported by model checkers were the most successful in obtaining relevant information about the application. Applying a number of different methods to study one particular model encourages a problem to be viewed from different angles. This gives complementary information about the model. We report on a variety of problems of the model found through various routes. Our main conclusion is that asking experts to apply different methods and tools at a sufficiently abstract level can be done effectively revealing a broad range of information about the considered application.

"No collision" in a protocol with n stations: a comparative study of formal proofs

Abstract: Formal methods are used both for designing a system and for checking that it satis es required properties. To prove that a nite system matches its speci cation, a common line of thought is to express properties in a suitable temporal logic, and with a model checker, automatically verify that the system satis es them. However this method does not work straightaway for systems composed of n similar components running in parallel, where n is not xed, like the protocol we present in this paper. Several ways out have been proposed. We have selected 3 di erent methods. We present them, apply them to the protocol and analyze how they compare.