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32
Process Algebra for Performance Evaluation
, 2000
"... This paper surveys the theoretical developments in the field of stochastic process algebras, process algebras where action occurrences may be subject to a delay that is determined by a random variable. A huge class of resourcesharing systems  like largescale computers, clientserver architectur ..."
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Cited by 52 (13 self)
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This paper surveys the theoretical developments in the field of stochastic process algebras, process algebras where action occurrences may be subject to a delay that is determined by a random variable. A huge class of resourcesharing systems  like largescale computers, clientserver architectures, networks  can accurately be described using such stochastic specification formalisms.
Automatic Verification of RealTime Communicating Systems by ConstraintSolving
 In Proc. of the 7th International Conference on Formal Description Techniques
, 1994
"... this paper, an algebra of timed processes with realvalued clocks is presented, which serves as a formal description language for realtime communicating systems. We show that requirements such as "a process will never reach an undesired state" can be verified by solving a simple class of constrai ..."
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Cited by 43 (15 self)
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this paper, an algebra of timed processes with realvalued clocks is presented, which serves as a formal description language for realtime communicating systems. We show that requirements such as "a process will never reach an undesired state" can be verified by solving a simple class of constraint systems on the clockvariables. A complete method for reachability analysis associated with the language is developed, and implemented as an automatic verification tool based on constraintsolving techniques. Finally as examples, we study and verify the safetyproperties of Fischer's mutual exclusion protocol and a railway crossing controller.
The Power of Reachability Testing for Timed Automata
 THEORETICAL COMPUTER SCIENCE
, 2001
"... The computational engine of the verification tool UPPAAL consists of a collection of efficient algorithms for the analysis of reachability properties of systems. Modelchecking of properties other than plain reachability ones may currently be carried out in such a tool as follows. Given a property t ..."
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Cited by 30 (11 self)
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The computational engine of the verification tool UPPAAL consists of a collection of efficient algorithms for the analysis of reachability properties of systems. Modelchecking of properties other than plain reachability ones may currently be carried out in such a tool as follows. Given a property to modelcheck, the user must provide a test automaton T for it. This test automaton must be such that the original system S has the property expressed by precisely when none of the distinguished reject states of T can be reached in the parallel composition of S with T . This raises the question of which properties may be analyzed by UPPAAL in such a way. This paper gives an answer to this question by providing a complete characterization of the class of properties for which modelchecking can be reduced to reachability testing in the sense outlined above. This result is obtained as a corollary of a stronger statement pertaining to the compositionality of the property language considered in this study. In particular, it is shown that our language is the least expressive compositional language that can express a simple safety property stating that no reject state can ever be reached. Finally, the property language characterizing the power of reachability testing is used to provide a definition of characteristic properties with respect to a timed version of the ready simulation preorder, for nodes of free, deterministic timed automata.
Semantics and Verification in Process Algebras with Data and Timing. Faculty of Mathematics and Computer Science, TU/e. 200305 S.V. Nedea. Analysis and Simulations of Catalytic Reactions. Faculty of Mathematics and Computer Science, TU/e. 200306 M.E.M.
 Faculty of Mathematics and Natural
, 2003
"... logic / software verification / programming languages; muCRL / programming languages; real time ..."
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Cited by 29 (1 self)
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logic / software verification / programming languages; muCRL / programming languages; real time
An Asynchronous Process Algebra with Multiple Clocks
 ESOP'94. Proceedings of the 5th European Symposium on Programming
, 1994
"... . In this paper we introduce a novel approach to the specification of realtime behaviour with process algebras. In contrast to the usual pattern, involving a fixed, measurable, and global notion of time, we suggest to represent realtime constraints indirectly through uninterpreted clocks enforcing ..."
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Cited by 26 (8 self)
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. In this paper we introduce a novel approach to the specification of realtime behaviour with process algebras. In contrast to the usual pattern, involving a fixed, measurable, and global notion of time, we suggest to represent realtime constraints indirectly through uninterpreted clocks enforcing broadcast synchronization between processes. Our approach advocates the use of asynchronous process algebras, which admit the faithful representation of nondeterministic and distributed computations. Technically, we present a nontrivial extension of the Calculus of Communicating Systems CCS [Mil89a] by multiple clocks with associated timeout and clock ignore operators. We illustrate the flexibility of the proposed process algebra, called PMC , by presenting examples of rather different nature. The timeout operators generalize the timeout of ATP [NS90] to multiple clocks. The main technical contribution is a complete axiomatization of strong bisimulation equivalence for a class of finites...
Timed Modal Specification  Theory and Tools
 IN PROC. OF THE 5TH INT. CONF. ON COMPUTER AIDED VERIFICATION, VOLUME 697 OF LECTURE NOTES IN COMPUTER SCIENCE (LNCS
, 1997
"... ..."
Basic Observables for Processes
 Information and Computation
, 1999
"... A general approach for defining behavioural preorders over process terms as the maximal precongruences induced by basic observables is examined. Three different observables, that provide information about the initial communication capabilities of processes and about the possibility that processes ..."
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Cited by 16 (4 self)
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A general approach for defining behavioural preorders over process terms as the maximal precongruences induced by basic observables is examined. Three different observables, that provide information about the initial communication capabilities of processes and about the possibility that processes get engaged in divergent computations, will be considered. We show that the precongruences induced by our basic observables coincide with intuitive and/or widely studied behavioural preorders. In particular, we retrieve in our setting the must preorder of De Nicola and Hennessy and the fair/should preorder introduced by Cleaveland and Natarajan and by Brinksma, Rensink and Vogler. A new form of testing preorder, which we call safemust, also emerges. The alternative characterizations we offer shed light on the differences between these preorders, and on the role played in their definition by tests for divergence. 1 Introduction In the classical theory of functional programming, the point...
Weak Bisimulation for Probabilistic Timed Automata
 PROC. OF SEFM’03, IEEE CS
, 2003
"... We are interested in describing timed systems that exhibit probabilistic behaviour. To this purpose, we consider a model of Probabilistic Timed Automata and introduce a concept of weak bisimulation for these automata, together with an algorithm to decide it. The weak bisimulation relation is shown t ..."
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Cited by 16 (6 self)
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We are interested in describing timed systems that exhibit probabilistic behaviour. To this purpose, we consider a model of Probabilistic Timed Automata and introduce a concept of weak bisimulation for these automata, together with an algorithm to decide it. The weak bisimulation relation is shown to be preserved when either time, or probability are abstracted away. As an application, we use weak bisimulation for Probabilistic Timed Automata to model and analyze a timing attack on the dining cryptographers protocol.
A timed LOTOS supporting a dense time domain and including new timed operators
, 1992
"... A time extended version of LOTOS, denoted Timed LOTOS, is proposed for the modelling of quantitative timed behaviours. In this language neither the syntax nor the semantics are restricted to a specific time domain, i.e. a dense time domain is supported as well. Timed LOTOS incorporates a notion of u ..."
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Cited by 15 (4 self)
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A time extended version of LOTOS, denoted Timed LOTOS, is proposed for the modelling of quantitative timed behaviours. In this language neither the syntax nor the semantics are restricted to a specific time domain, i.e. a dense time domain is supported as well. Timed LOTOS incorporates a notion of urgency which is restricted to the internal actions. This is usually referred to as the maximal progress or minimum delay property. Timed LOTOS processes have also some pleasing properties such as the deadlock freeness property (i.e. processes can never stop the progression of time), and the persistency property (i.e. by idling, a process will not lose any capability of performing an action). In Timed LOTOS the delay operator is powerful because it allows the specification of a time interval in which the delay is nonderministically chosen. Two other powerful timed operators are defined which allow the expression of timed constraints on interactions, i.e. on actions involving several processe...
Confidentiality for Multithreaded Programs via Bisimulation
 In Proc. Andrei Ershov International Conference on Perspectives of System Informatics, volume 2890 of LNCS
, 2003
"... Bisimulation has been a popular foundation for characterizing the confidentiality properties of concurrent programs. However, because a variety of bisimulation definitions are available in the literature, it is often di#cult to pin down the "right" definition for modeling a particular attacker. ..."
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Cited by 11 (1 self)
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Bisimulation has been a popular foundation for characterizing the confidentiality properties of concurrent programs. However, because a variety of bisimulation definitions are available in the literature, it is often di#cult to pin down the "right" definition for modeling a particular attacker. Focusing on timing and probabilitysensitive confidentiality for sharedmemory multithreaded programs, we clarify the relation between di#erent kinds of bisimulation by proving inclusion results.