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A Survey of Concurrent METATEM  The Language and its Applications
 Temporal Logic — Proceedings of the First International Conference (LNAI Volume 827
, 1994
"... . In this paper we present a survey of work relating to the Concurrent METATEM programming language. In addition to a description of the basic Concurrent METATEM system, which incorporates the direct execution of temporal formulae, a variety of extensions that have either been implemented or propo ..."
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Cited by 108 (9 self)
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. In this paper we present a survey of work relating to the Concurrent METATEM programming language. In addition to a description of the basic Concurrent METATEM system, which incorporates the direct execution of temporal formulae, a variety of extensions that have either been implemented or proposed are outlined. Although still in the development stage, there appear to be many areas where such a language could be applied. We present a variety of sample applications, highlighting the particular features of Concurrent METATEM that we believe will make it appropriate for use in these areas. 1 Introduction Concurrent METATEM is a language based upon the direct execution of temporal formulae [15]. It consists of two distinct aspects: an execution mechanism for temporal formulae in a particular form; and an operational model that treats single executable temporal logic programs as asynchronously executing objects in a concurrent objectbased system. The motivation for the development of t...
A framework for security analysis of mobile wireless networks
 Theoretical Computer Science
, 2006
"... We present a framework for specification and security analysis of communication protocols for mobile wireless networks. This setting introduces new challenges which are not being addressed by classical protocol analysis techniques. The main complication stems from the fact that the actions of inter ..."
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Cited by 28 (2 self)
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We present a framework for specification and security analysis of communication protocols for mobile wireless networks. This setting introduces new challenges which are not being addressed by classical protocol analysis techniques. The main complication stems from the fact that the actions of intermediate nodes and their connectivity can no longer be abstracted into a single unstructured adversarial environment as they form an inherent part of the system’s security. In order to model this scenario faithfully, we present a broadcast calculus which makes a clear distinction between the protocol processes and the network’s connectivity graph, which may change independently from protocol actions. We identify a property characterising an important aspect of security in this setting and express it using behavioural equivalences of the calculus. We complement this approach with a control flow analysis which enables us to automatically check this property on a given network and attacker specification. 1
Programming With Broadcasts
 In CONCUR
, 1993
"... . [Pra91, Pra92] develop CBS, a CCSlike calculus [Mil89] where processes communicate by broadcasting values along a single channel. These values are hidden or restricted by translation to noise. This paper types CBS and restricts it to processes with a unique response to each input. Nondeterminism ..."
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Cited by 20 (7 self)
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. [Pra91, Pra92] develop CBS, a CCSlike calculus [Mil89] where processes communicate by broadcasting values along a single channel. These values are hidden or restricted by translation to noise. This paper types CBS and restricts it to processes with a unique response to each input. Nondeterminism arises only if two processes in parallel both wish to transmit. These restrictions do not reduce the programming power of CBS. But strong and weak bisimulation can now be defined exactly as in CCS, yet capture observationally meaningful relations. Weak bisimulation is a congruence. This paper also shows how to program in CBS in a (lazy) ML framework. A simple CBS simulator is given, and a parallel implementation discussed. The simulator represents data evaluation, recursion and conditionals directly in Lazy ML. It implements an extended CBS with evaluation as well as communication transitions. [Pra91, Pra92] develop a CCSlike [Mil89] calculus of broadcasting systems, CBS. This paper continu...
A Process Calculus for Mobile Ad Hoc Networks
"... Abstract. We present the ωcalculus, a process calculus for formally modeling and reasoning about Mobile Ad Hoc Wireless Networks (MANETs) and their protocols. The ωcalculus naturally captures essential characteristics of MANETs, including the ability of a MANET node to broadcast a message to any o ..."
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Cited by 19 (1 self)
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Abstract. We present the ωcalculus, a process calculus for formally modeling and reasoning about Mobile Ad Hoc Wireless Networks (MANETs) and their protocols. The ωcalculus naturally captures essential characteristics of MANETs, including the ability of a MANET node to broadcast a message to any other node within its physical transmission range (and no others), and to move in and out of the transmission range of other nodes in the network. A key feature of the ωcalculus is the separation of a node’s communication and computational behavior, described by an ωprocess, from the description of its physical transmission range, referred to as an ωprocess interface. Our main technical results are as follows. We give a formal operational semantics of the ωcalculus in terms of labeled transition systems and show that the state reachability problem is decidable for finitecontrol ωprocesses. We also prove that the ωcalculus is a conservative extension of the πcalculus, and that late bisimulation (appropriately lifted from the πcalculus to the ωcalculus) is a congruence. Congruence results are also established for a weak version of late bisimulation, which abstracts away from two types of internal actions: τactions, as in the πcalculus, and µactions, signaling node movement. Finally, we illustrate the practical utility of the calculus by developing and analyzing a formal model of a leaderelection protocol for MANETs. 1
Towards a Calculus for Wireless Systems
"... In wireless systems, the communication mechanism combines features of broadcast, synchrony, and asynchrony. We develop an operational semantics for a calculus of wireless systems. We present a Reduction Semantics and a Labelled Transition Semantics and prove a correspondence result between them. W ..."
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Cited by 18 (0 self)
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In wireless systems, the communication mechanism combines features of broadcast, synchrony, and asynchrony. We develop an operational semantics for a calculus of wireless systems. We present a Reduction Semantics and a Labelled Transition Semantics and prove a correspondence result between them. We first consider a core calculus, essentially with only the primitives for communication, and then a few extensions. A major goal of the semantics is to describe the forms of interferences among the activities of processes that are peculiar of wireless systems. Such interferences occur when a location is simultaneously reached by two transmissions.
A Calculus Of Value Broadcasts
 IN PARLE'93
, 1993
"... Computation can be modelled as a sequence of values, each broadcast by one agent and instantaneously audible to all those in parallel with it. Listening agents receive the value; others lose it. Subsystems interface via translators; these can scramble values and thus hide or restrict them. Examples ..."
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Cited by 17 (5 self)
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Computation can be modelled as a sequence of values, each broadcast by one agent and instantaneously audible to all those in parallel with it. Listening agents receive the value; others lose it. Subsystems interface via translators; these can scramble values and thus hide or restrict them. Examples show the calculus describing this model to be a powerful and natural programming tool. Weak bisimulation, a candidate for observational equivalence, is defined on the basis that receiving a value can be matched by losing it.
Un Calcul De Constructions Infinies Et Son Application A La Verification De Systemes Communicants
, 1996
"... m networks and the recent works of Thierry Coquand in type theory have been the most important sources of motivation for the ideas presented here. I wish to specially thank Roberto Amadio, who read the manuscript in a very short delay, providing many helpful comments and remarks. Many thanks also to ..."
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Cited by 16 (0 self)
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m networks and the recent works of Thierry Coquand in type theory have been the most important sources of motivation for the ideas presented here. I wish to specially thank Roberto Amadio, who read the manuscript in a very short delay, providing many helpful comments and remarks. Many thanks also to Luc Boug'e, who accepted to be my oficial supervisor, and to the chair of the jury, Michel Cosnard, who opened to me the doors of the LIP. During these last three years in Lyon I met many wonderful people, who then become wonderful friends. Miguel, Nuria, Veronique, Patricia, Philippe, Pia, Rodrigo, Salvador, Sophie : : : with you I have shared the happiness and sadness of everyday life, those little things which make us to remember someone forever. I also would like to thank the people from "Tango de Soie", for all those funny nights at the Caf'e Moulin Joly. Thanks too to the Uruguayan research community in Computer Science (specially to Cristina Cornes and Alberto Pardo) w
A Broadcastbased Calculus for Communicating Systems
, 2000
"... This paper presents a process calculus for recongurable communicating systems which has broadcast as basic communication primitive, and we provide an operational semantics for this calculus. We illustrate the calculus through some examples, and we propose three behavioral equivalences for reasoning ..."
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Cited by 16 (1 self)
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This paper presents a process calculus for recongurable communicating systems which has broadcast as basic communication primitive, and we provide an operational semantics for this calculus. We illustrate the calculus through some examples, and we propose three behavioral equivalences for reasoning about systems of broadcasting processes, namely, barbed equivalence, stepequivalence and labelled bisimilarity. An important result, is that all these relations coincide, providing dierent ways to study the equivalence/nonequivalence of two systems. Then, we provide a direct characterization for the strong congruence relation induced by these equivalences. Finally, we give a complete axiomatisation for strong congruence. 1
CoInductive Types in Coq: An Experiment with the Alternating Bit Protocol
, 1995
"... We describe an experience concerning the implementation and use of coinductive types in the proof editor Coq. Coinductive types are recursive types which, opposite to inductive ones, may be inhabited by infinite objects. In order to illustrate their use in Coq, we describe an axiomatisation of ..."
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Cited by 12 (1 self)
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We describe an experience concerning the implementation and use of coinductive types in the proof editor Coq. Coinductive types are recursive types which, opposite to inductive ones, may be inhabited by infinite objects. In order to illustrate their use in Coq, we describe an axiomatisation of a calculus of broadcasting systems where recursive processes are represented using infinite objects. This calculus is used for developing a verification proof of the alternating bit protocol. Keywords: Program Verification, Type Theory, CoInductive Types, Communicating Processes R'esum'e Dans cet article nous d'ecrivons une exp'erience concernant l'implantation et l'utilisation de types coinductifs dans l'environnement de preuves Coq. Les types coinductifs sont des types recursifs qui, `a la diff'erence des types inductifs, peuvent etre habit'es par des objets infinis. Pour illustrer leur utilisation dans Coq nous d'ecrivons comment axiomatiser un calcul de processus qui communiq...
True Concurrency Semantics for a Linear Logic Programming Language with Broadcast Communication
 In Proc. of TAPSOFT'93, volume 668 of Lecture Notes in Computer Science
, 1993
"... We define a true concurrency semantics for LO, a reactive programming language characterized by dynamically reconfigurable agents (processes), with interagent communication implemented as broadcasting and logical operators corresponding to Linear Logic connectives. Our semantic model is given by t ..."
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Cited by 11 (3 self)
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We define a true concurrency semantics for LO, a reactive programming language characterized by dynamically reconfigurable agents (processes), with interagent communication implemented as broadcasting and logical operators corresponding to Linear Logic connectives. Our semantic model is given by the wellknown Chemical Abstract Machine formalism, where concurrent events happen in the form of chemicallike reactions.