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331
The Linear Time-Branching Time Spectrum II - The semantics of sequential systems with silent moves
, 1993
"... ion Rule (KFAR) (Baeten, Bergstra & Klop [3]), expresses a global fairness assumption. It says that when possible a system will escape from any cycle of internal actions. Some form of KFAR is crucial for many protocal verifications with unreliable channels, and for that reason preorders and equi ..."
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Cited by 375 (21 self)
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ion Rule (KFAR) (Baeten, Bergstra & Klop [3]), expresses a global fairness assumption. It says that when possible a system will escape from any cycle of internal actions. Some form of KFAR is crucial for many protocal verifications with unreliable channels, and for that reason preorders and equivalences that satisfy KFAR are of special interest. Must preorders and divergence sensitive ones cannot satisfy KFAR. In Bergstra, Klop & Olderog [7] it is shown that the combination of KFAR with failure semantics is inconsistent, but they formulate a weaker version of KFAR that is satisfied in failure may-semantics. Still the combination of KFAR \Gamma and the liveness requirement appears to require global testing, and is only satisfied in the semantics between contrasimulation (C) and stability respecting branching bisimulation (BB s ). These requirements would reduce the number of suitable preorders to 18. It is in general a good strategy to do your verifications using the finest preorde...
Probabilistic Simulations for Probabilistic Processes
, 1994
"... Several probabilistic simulation relations for probabilistic systems are defined and evaluated according to two criteria: compositionality and preservation of "interesting" properties. Here, the interesting properties of a system are identified with those that are expressible in an untimed ..."
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Cited by 361 (19 self)
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Several probabilistic simulation relations for probabilistic systems are defined and evaluated according to two criteria: compositionality and preservation of "interesting" properties. Here, the interesting properties of a system are identified with those that are expressible in an untimed version of the Timed Probabilistic concurrent Computation Tree Logic (TPCTL) of Hansson. The definitions are made, and the evaluations carried out, in terms of a general labeled transition system model for concurrent probabilistic computation. The results cover weak simulations, which abstract from internal computation, as well as strong simulations, which do not.
Priorities in process algebra
, 1999
"... This chapter surveys the semantic rami cations of extending traditional process algebras with notions of priority that allow for some transitions to be given precedence over others. The need for these enriched formalisms arises when one wishes to model system features such asinterrupts, prioritized ..."
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Cited by 119 (12 self)
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This chapter surveys the semantic rami cations of extending traditional process algebras with notions of priority that allow for some transitions to be given precedence over others. The need for these enriched formalisms arises when one wishes to model system features such asinterrupts, prioritized choice, orreal-time behavior. Approaches to priority in process algebras can be classi ed according to whether the induced notion of pre-emption on transitions is global or local and whether priorities are static or dynamic. Early work in the area concentrated on global preemption and static priorities and led to formalisms for modeling interrupts and aspects of real-time, such as maximal progress, in centralized computing environments. More recent research has investigated localized notions of pre-emption in which the distribution of systems is taken into account, as well as dynamic priority approaches, i.e., those where priority values may change as systems evolve. The latter allows one to model behavioral phenomena such as scheduling algorithms and also enables the e cient encoding of real-time semantics. Technically, this chapter studies the di erent models of priorities by presenting extensions of Milner's Calculus of Communicating Systems (CCS) with static and dynamic priority as well as with notions of global and local pre-emption. In each case the operational semantics of CCS is modi ed appropriately, behavioral theories based on strong and weak bisimulation are given, and related approaches for di erent process-algebraic settings are discussed.
Reasoning about Rings
, 1995
"... The ring is a useful means of structuring concurrent processes. Processes communicate by passing a token in a fixed direction; the process that possesses the token is allowed to perfrom certain actions. Usually, correctness properties are expected to hold irrespective of the size of the ring. We sho ..."
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Cited by 112 (9 self)
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The ring is a useful means of structuring concurrent processes. Processes communicate by passing a token in a fixed direction; the process that possesses the token is allowed to perfrom certain actions. Usually, correctness properties are expected to hold irrespective of the size of the ring. We show that the problem of checking many useful correctness properties for rings of all sizes can be reduced to checking them on ring of sizes up to a small cutoff size. We apply our results to the verification of a mutual exclusion protocol and Milner's scheduler protocol. 1
The P2P Approach to Interorganizational Workflows
- Proceedings of the 13th International Conference on Advanced Information Systems Engineering (CAiSE’01), volume 2068 of Lecture Notes in Computer Science
"... . This paper describes in an informal way the Public-To-Private (P2P) approach to interorganizational workflows, which is based on a notion of inheritance. The approach consists of three steps: (1) create a common understanding of the interorganizational workflow by specifying a shared public wor ..."
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Cited by 105 (9 self)
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. This paper describes in an informal way the Public-To-Private (P2P) approach to interorganizational workflows, which is based on a notion of inheritance. The approach consists of three steps: (1) create a common understanding of the interorganizational workflow by specifying a shared public workflow, (2) partition the public workflow over the organizations involved, and (3) for each organization, create a private workflow which is a subclass of the respective part of the public workflow. Using an example, we explain that the P2P approach yields an interorganizational workflow which is guaranteed to realize the behavior specified in the public workflow. 1 Introduction In today's corporations, products and services are typically created by business processes, and workflow technology can be used for enhancing the flexibility and efficiency of these processes [14, 19]. Corporations often operate across organizational boundaries, for example in E-commerce and extended enterprise...
Service-oriented design: a multi-viewpoint approach
- INTERNATIONAL JOURNAL OF COOPERATIVE INFORMATION SYSTEMS
, 2004
"... As the technology associated to the “Web Services” trend gains significant adoption, the need for a corresponding design approach becomes increasingly important. This paper introduces a foundational model for designing (composite) services. The innovation of this model lies in the identification of ..."
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Cited by 88 (10 self)
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As the technology associated to the “Web Services” trend gains significant adoption, the need for a corresponding design approach becomes increasingly important. This paper introduces a foundational model for designing (composite) services. The innovation of this model lies in the identification of four interrelated viewpoints (interface behaviour, provider behaviour, choreography, and orchestration) and their formalisation from a control-flow perspective in terms of Petri nets. By formally capturing the interrelationships between these viewpoints, the proposal enables the static verification of the consistency of composite services designed in a cooperative and incremental manner. A proof-of-concept simulation and verification tool has been developed to test the possibilities of the proposed model.
A brief history of process algebra
- THEOR. COMPUT. SCI
, 2004
"... This note addresses the history of process algebra as an area of research in concurrency theory, the theory of parallel and distributed systems in computer science. Origins are traced back to the early seventies of the twentieth century, and developments since that time are sketched. The author giv ..."
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Cited by 84 (1 self)
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This note addresses the history of process algebra as an area of research in concurrency theory, the theory of parallel and distributed systems in computer science. Origins are traced back to the early seventies of the twentieth century, and developments since that time are sketched. The author gives his personal views on these matters. He also considers the present situation, and states some challenges for the future.
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 resource-sharing systems --- like large-scale computers, client-server architectur ..."
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Cited by 71 (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 resource-sharing systems --- like large-scale computers, client-server architectures, networks --- can accurately be described using such stochastic specification formalisms.
A Partial Order Approach to Branching Time Logic Model Checking
- Information and Computation
, 1994
"... Partial order techniques enable reducing the size of the state graph used for model checking, thus alleviating the `state space explosion' problem. These reductions are based on selecting a subset of the enabled operations from each program state. So far, these methods have been studied, implem ..."
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Cited by 65 (15 self)
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Partial order techniques enable reducing the size of the state graph used for model checking, thus alleviating the `state space explosion' problem. These reductions are based on selecting a subset of the enabled operations from each program state. So far, these methods have been studied, implemented and demonstrated for assertional languages that model the executions of a program as computation sequences, in particular the logic LTL (linear temporal logic). The present paper shows, for the first time, how this approach can be applied to languages that model the behavior of a program as a tree. We study here partial order reductions for branching temporal logics, e.g., the logics CTL and CTL (all logics with the next-time operator removed) and process algebras such as CCS. Conditions on the subset of successors from each node to guarantee reduction that preserves CTL properties are given. Provided experimental results show that the reduction is substantial. 1 Introduction Partial ord...
