The Experts below are selected from a list of 75792 Experts worldwide ranked by ideXlab platform
Sébastien Tixeuil - One of the best experts on this subject based on the ideXlab platform.
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Weak vs. Self vs. Probabilistic Stabilization
International Journal of Foundations of Computer Science, 2015Co-Authors: Stéphane Devismes, Sébastien Tixeuil, Masafumi YamashitaAbstract:Self-stabilization is a strong property, which guarantees that a distributed system always resumes a Correct Behavior starting from an arbitrary initial state. Since it is a strong property, some problems cannot have self-stabilizing solutions. Weaker guarantees hence have been later introduced to cope with impossibility results, e.g., probabilistic self-stabilization only guarantees probabilistic convergence to a Correct Behavior, and weak stabilization only guarantees the possibility of convergence. In this paper, we investigate the relative power of self, probabilistic, and weak stabilization, with respect to the set of problems that can be solved. Weak stabilization is by definition stronger than self-stabilization and probabilistic self-stabilization in that precise sense. We first show that weak stabilization allows to solve problems having no self-stabilizing solution. We then show that any finite state deterministic weak stabilizing algorithm to solve a problem under the strongly fair scheduler is always a probabilistic self-stabilizing algorithm to solve the same problem under the randomized scheduler. Unfortunately, this good property does not hold in general for infinite state algorithms. We however show that for some classes of infinite state algorithms, this property holds. These results hint at more practical use of weak stabilizing algorithms, as they are easier to design and prove their Correctness than their self-stabilizing and probabilistic self-stabilizing counterparts.
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Stabilizing data-link over non-FIFO channels with optimal fault-resilience
Information Processing Letters, 2011Co-Authors: Shlomi Dolev, Swan Dubois, Maria Potop-butucaru, Sébastien TixeuilAbstract:Self-stabilizing systems have the ability to converge to a Correct Behavior when started in any configuration. Most of the work done so far in the self-stabilization area assumed either communication via shared memory or via FIFO channels.This paper is the first to lay the bases for the design of self-stabilizing message passing algorithms over unreliable non-FIFO channels. We propose an optimal stabilizing data-link layer that emulates a reliable FIFO communication channel over unreliable capacity bounded non-FIFO channels (the channel capacity is known to the protocol).
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ICDCS - Weak vs. Self vs. Probabilistic Stabilization
2008 The 28th International Conference on Distributed Computing Systems, 2008Co-Authors: Stéphane Devismes, Sébastien Tixeuil, Masafumi YamashitaAbstract:Self-stabilization is a strong property which guarantees that a network always resume a Correct Behavior starting from an arbitrary initial state. Weaker guarantees have later been introduced to cope with impossibility results: probabilistic stabilization only gives probabilistic convergence to a Correct Behavior. Also, weak-stabilization only gives the possibility of convergence. In this paper, we investigate the relative power of weak, self, and probabilistic stabilization, with respect to the set of problems that can be solved. We formally prove that in that sense, weak stabilization is strictly stronger that self-stabilization. Also, we refine previous results on weak stabilization to prove that, for practical schedule instances, a deterministic weak-stabilizing protocol can be turned into a probabilistic self-stabilizing one. This latter result hints at more practical use of weak-stabilization, as such algorithms are easier to design and prove than their (probabilistic) self-stabilizing counterparts.
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Weak vs. Self vs. Probabilistic Stabilization
arXiv: Distributed Parallel and Cluster Computing, 2007Co-Authors: Stéphane Devismes, Sébastien Tixeuil, Masafumi YamashitaAbstract:Self-stabilization is a strong property that guarantees that a network always resume Correct Behavior starting from an arbitrary initial state. Weaker guarantees have later been introduced to cope with impossibility results: probabilistic stabilization only gives probabilistic convergence to a Correct Behavior. Also, weak stabilization only gives the possibility of convergence. In this paper, we investigate the relative power of weak, self, and probabilistic stabilization, with respect to the set of problems that can be solved. We formally prove that in that sense, weak stabilization is strictly stronger that self-stabilization. Also, we refine previous results on weak stabilization to prove that, for practical schedule instances, a deterministic weak-stabilizing protocol can be turned into a probabilistic self-stabilizing one. This latter result hints at more practical use of weak-stabilization, as such algorthms are easier to design and prove than their (probabilistic) self-stabilizing counterparts.
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Autostabilisation et protocoles réseau
Revue des Sciences et Technologies de l'Information - Série TSI : Technique et Science Informatiques, 2004Co-Authors: Colette Johnen, Franck Petit, Sébastien TixeuilAbstract:In 1974, E.W. Dijkstra defined self-stabilization as the property for a distributed system to recover by itself a Correct Behavior in a finite number of steps, starting from any initial state. Thus, self-stabilization is a simple and efficient way to tolerate transient faults or failures. This paper surveys works that propose self-stabilizing solutions to problems arising in Computer Networks, such as routing and transport layers, or network control protocols. We also review techniques to design self-stabilizing protocols, and mechanisms that reduce the stabilization time when the number of hitting faults is small.
Jörg Desel - One of the best experts on this subject based on the ideXlab platform.
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Symbolic abstraction and deadlock-freeness verification of inter-enterprise processes
Data & Knowledge Engineering, 2011Co-Authors: Kais Klai, Samir Tata, Jörg DeselAbstract:The design of complex inter-enterprise business processes (IEBP) is generally performed in a modular way. Each process is designed separately and then the whole IEBP is obtained by composition. Even if such a modular approach is intuitive and facilitates the design problem, it poses the problem that Correct Behavior of each business process of the IEBP taken alone does not guarantee a Correct Behavior of the composed IEBP (i.e. properties are not preserved by composition). Proving Correctness of the (unknown) composed process is strongly related to the model checking problem of a system model. Among others, the symbolic observation graph based approach has proven to be very helpful for efficient model checking in general. Since it is heavily based on abstraction techniques and thus hides detailed information about system components that are not relevant for the Correctness decision, it is promising to transfer this concept to the problem raised in this paper: How can the symbolic observation graph technique be adapted and employed for process composition? Answering this question is the aim of this paper.
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Symbolic abstraction and deadlock freeness verification of inter-enterprise processes
2009Co-Authors: Kais Klai, Samir Tata, Jörg DeselAbstract:Web services can be viewed as processes of an enterprise which are used by (processes of) other enterprises. So, when offering a web service, it is necessary to publish sufficient information about the interface of the web service process. On the other hand, details of the internal behaviour of a web service should be hidden. So the design of complex inter-enterprise business processes(IEBP) employing web services is generally performed in a modular way. Each service is designed separately from the others and then the whole IEBP is obtained by composition. Even if such a modular approach is intuitive and facilitates the design problem, it poses the problem that Correct Behavior of each service of the IEBP taken alone does not guarantee a Correct Behavior of the composed IEBP (i.e. properties are not preserved by composition). In this paper, we address this problem. First, we propose to use a new variant of symbolic observation graphs as an abstraction of any service of the IEBP (only cooperative activities are visible). Local deadlock freeness can be checked efficiently on such an abstraction using symbolic algorithms. Second, we propose to synchronize the symbolic observation graphs associated with the different processes of the IEBP and supply an efficient algorithm for the verification of deadlock freeness of the synchronized product. The deadlock freeness of such a product guarantees a Correct possible cooperation between the underlying processes (i.e. a deadlock free cooperation).
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BPM - Symbolic Abstraction and Deadlock-Freeness Verification of Inter-enterprise Processes
Lecture Notes in Computer Science, 2009Co-Authors: Kais Klai, Samir Tata, Jörg DeselAbstract:The design of complex inter-enterprise business processes (IEBP) is generally performed in a modular way. Each process is designed separately from the others and then the whole IEBP is obtained by composition. Even if such a modular approach is intuitive and facilitates the design problem, it poses the problem that Correct Behavior of each business process of the IEBP taken alone does not guarantee a Correct Behavior of the composed IEBP (i.e. properties are not preserved by composition). Proving Correctness of the (unknown) composed process is strongly related to the model checking problem of a system model. Among others, the symbolic observation graph based approach has proven to be very helpful for efficient model checking in general. Since it is heavily based on abstraction techniques and thus hides detailed information about system components that are not relevant for the Correctness decision, it is promising to transfer this concept to the problem rised in this paper: How can the symbolic observation graph technique be adapted and employed for process composition? Answering this question is the aim of this paper.
Masafumi Yamashita - One of the best experts on this subject based on the ideXlab platform.
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Weak vs. Self vs. Probabilistic Stabilization
International Journal of Foundations of Computer Science, 2015Co-Authors: Stéphane Devismes, Sébastien Tixeuil, Masafumi YamashitaAbstract:Self-stabilization is a strong property, which guarantees that a distributed system always resumes a Correct Behavior starting from an arbitrary initial state. Since it is a strong property, some problems cannot have self-stabilizing solutions. Weaker guarantees hence have been later introduced to cope with impossibility results, e.g., probabilistic self-stabilization only guarantees probabilistic convergence to a Correct Behavior, and weak stabilization only guarantees the possibility of convergence. In this paper, we investigate the relative power of self, probabilistic, and weak stabilization, with respect to the set of problems that can be solved. Weak stabilization is by definition stronger than self-stabilization and probabilistic self-stabilization in that precise sense. We first show that weak stabilization allows to solve problems having no self-stabilizing solution. We then show that any finite state deterministic weak stabilizing algorithm to solve a problem under the strongly fair scheduler is always a probabilistic self-stabilizing algorithm to solve the same problem under the randomized scheduler. Unfortunately, this good property does not hold in general for infinite state algorithms. We however show that for some classes of infinite state algorithms, this property holds. These results hint at more practical use of weak stabilizing algorithms, as they are easier to design and prove their Correctness than their self-stabilizing and probabilistic self-stabilizing counterparts.
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ICDCS - Weak vs. Self vs. Probabilistic Stabilization
2008 The 28th International Conference on Distributed Computing Systems, 2008Co-Authors: Stéphane Devismes, Sébastien Tixeuil, Masafumi YamashitaAbstract:Self-stabilization is a strong property which guarantees that a network always resume a Correct Behavior starting from an arbitrary initial state. Weaker guarantees have later been introduced to cope with impossibility results: probabilistic stabilization only gives probabilistic convergence to a Correct Behavior. Also, weak-stabilization only gives the possibility of convergence. In this paper, we investigate the relative power of weak, self, and probabilistic stabilization, with respect to the set of problems that can be solved. We formally prove that in that sense, weak stabilization is strictly stronger that self-stabilization. Also, we refine previous results on weak stabilization to prove that, for practical schedule instances, a deterministic weak-stabilizing protocol can be turned into a probabilistic self-stabilizing one. This latter result hints at more practical use of weak-stabilization, as such algorithms are easier to design and prove than their (probabilistic) self-stabilizing counterparts.
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Weak vs. Self vs. Probabilistic Stabilization
arXiv: Distributed Parallel and Cluster Computing, 2007Co-Authors: Stéphane Devismes, Sébastien Tixeuil, Masafumi YamashitaAbstract:Self-stabilization is a strong property that guarantees that a network always resume Correct Behavior starting from an arbitrary initial state. Weaker guarantees have later been introduced to cope with impossibility results: probabilistic stabilization only gives probabilistic convergence to a Correct Behavior. Also, weak stabilization only gives the possibility of convergence. In this paper, we investigate the relative power of weak, self, and probabilistic stabilization, with respect to the set of problems that can be solved. We formally prove that in that sense, weak stabilization is strictly stronger that self-stabilization. Also, we refine previous results on weak stabilization to prove that, for practical schedule instances, a deterministic weak-stabilizing protocol can be turned into a probabilistic self-stabilizing one. This latter result hints at more practical use of weak-stabilization, as such algorthms are easier to design and prove than their (probabilistic) self-stabilizing counterparts.
M. Amparo Vila - One of the best experts on this subject based on the ideXlab platform.
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Correct Behavior identification system in a Tagged World
Expert Systems with Applications, 2009Co-Authors: Miguel Delgado, María Ros, M. Amparo VilaAbstract:This paper presents a system that is able to process the information provided by a Tagged World to identify user's Behavior and to produce alarms in dangerous situations. The system inputs are signals from sensors, which are used to recognize Correct Behavior (action sequences) by Inductive Learning, using Data Mining techniques. The inference engine is a reasoning device that is implemented by means of Regular Grammars. It permits us to control user's Behavior. As output, the system produces and sends alarms when a user action sequence is wrong, indicating the erroneous actions, forgotten future, and so on. To test our system, the Tagged World is supposed to be at a house, where we have used RFID technology to control the objects inside it.
Kais Klai - One of the best experts on this subject based on the ideXlab platform.
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Symbolic abstraction and deadlock-freeness verification of inter-enterprise processes
Data & Knowledge Engineering, 2011Co-Authors: Kais Klai, Samir Tata, Jörg DeselAbstract:The design of complex inter-enterprise business processes (IEBP) is generally performed in a modular way. Each process is designed separately and then the whole IEBP is obtained by composition. Even if such a modular approach is intuitive and facilitates the design problem, it poses the problem that Correct Behavior of each business process of the IEBP taken alone does not guarantee a Correct Behavior of the composed IEBP (i.e. properties are not preserved by composition). Proving Correctness of the (unknown) composed process is strongly related to the model checking problem of a system model. Among others, the symbolic observation graph based approach has proven to be very helpful for efficient model checking in general. Since it is heavily based on abstraction techniques and thus hides detailed information about system components that are not relevant for the Correctness decision, it is promising to transfer this concept to the problem raised in this paper: How can the symbolic observation graph technique be adapted and employed for process composition? Answering this question is the aim of this paper.
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Symbolic abstraction and deadlock freeness verification of inter-enterprise processes
2009Co-Authors: Kais Klai, Samir Tata, Jörg DeselAbstract:Web services can be viewed as processes of an enterprise which are used by (processes of) other enterprises. So, when offering a web service, it is necessary to publish sufficient information about the interface of the web service process. On the other hand, details of the internal behaviour of a web service should be hidden. So the design of complex inter-enterprise business processes(IEBP) employing web services is generally performed in a modular way. Each service is designed separately from the others and then the whole IEBP is obtained by composition. Even if such a modular approach is intuitive and facilitates the design problem, it poses the problem that Correct Behavior of each service of the IEBP taken alone does not guarantee a Correct Behavior of the composed IEBP (i.e. properties are not preserved by composition). In this paper, we address this problem. First, we propose to use a new variant of symbolic observation graphs as an abstraction of any service of the IEBP (only cooperative activities are visible). Local deadlock freeness can be checked efficiently on such an abstraction using symbolic algorithms. Second, we propose to synchronize the symbolic observation graphs associated with the different processes of the IEBP and supply an efficient algorithm for the verification of deadlock freeness of the synchronized product. The deadlock freeness of such a product guarantees a Correct possible cooperation between the underlying processes (i.e. a deadlock free cooperation).
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BPM - Symbolic Abstraction and Deadlock-Freeness Verification of Inter-enterprise Processes
Lecture Notes in Computer Science, 2009Co-Authors: Kais Klai, Samir Tata, Jörg DeselAbstract:The design of complex inter-enterprise business processes (IEBP) is generally performed in a modular way. Each process is designed separately from the others and then the whole IEBP is obtained by composition. Even if such a modular approach is intuitive and facilitates the design problem, it poses the problem that Correct Behavior of each business process of the IEBP taken alone does not guarantee a Correct Behavior of the composed IEBP (i.e. properties are not preserved by composition). Proving Correctness of the (unknown) composed process is strongly related to the model checking problem of a system model. Among others, the symbolic observation graph based approach has proven to be very helpful for efficient model checking in general. Since it is heavily based on abstraction techniques and thus hides detailed information about system components that are not relevant for the Correctness decision, it is promising to transfer this concept to the problem rised in this paper: How can the symbolic observation graph technique be adapted and employed for process composition? Answering this question is the aim of this paper.
