A test generation framework for quiescent real-time systems

We present an extension of Tretmans theory and algorithm for test generation for input-output transition systems to real-time systems. Our treatment is based on an operational interpretation of the notion of quiescence in the context of real-time behaviour. This gives rise to a family of implementation relations parameterized by observation durations for quiescence. We define a nondeterministic (parameterized) test generation algorithm that generates test cases that are sound with respect to the corresponding implementation relation. Also, the test generation is exhaustive in the sense that for each non-conforming implementation a test case can be generated that detects the non-conformance

Testing finite state machines presenting stochastic time and timeouts

In this paper we define a formal framework to test implementations that can be represented by the class of finite state machines introduced in [10]. First, we introduce an appropriate notion of test. Next, we provide an algorithm to derive test suites from specifications such that the constructed test suites are sound and complete with respect to two of the conformance relations introduced in [10]. In fact, the current paper together with [10] constitute a complete formal theory to specify and test the class of systems covered by the before mentioned stochastic finite state machines

Exploiting symmetry in protocol testing

Contains fulltext : 18698_explsyinp.pdf ( ) (Open Access)24 p

Minimizable timed automata

Contains fulltext : 28250.pdf (preprint version ) (Open Access

Lower and upper bounds for reductions of types in λω and λP

For several important systems of the λ-cube we study the time-complexity of type conversion

Focus points and convergent process operators (A proof strategy for protocol verification)

We present a strategy for finding algebraic correctness proofs for communication systems. It is described in the setting of μCRL [11], which is, roughly, ACP [2,3] extended with a formal treatment of the interaction between data and processes. The strategy has already been applied successfully in [4] and [10], but was not explicitly identified as such. Moreover, the protocols that were verified in these papers were rather complex, so that the general picture was obscured by the amount of details. In this paper, the proof strategy is materialised in the form of definitions and theorems. These results reduce a large part of protocol verification to a number of trivial facts concerning data parameters occurring in implementation and specification. This greatly simplifies protocol verifications and makes our approach amenable to mechanical assistance; experiments in this direction seem promising. The strategy is illustrated by several small examples and one larger example, the Concurrent Alternating Bit Protocol (CABP). Although simple, this protocol contains a large amount of internal parallelism. so that all relevant issues make their appearance