Results 1  10
of
36
Reactive Systems, Barbed Semantics, and the Mobile Ambients
"... Reactive systems, proposed by Leifer and Milner, represent a metaframework aimed at deriving behavioral congruences for those specification formalisms whose operational semantics is provided by rewriting rules. Despite its applicability, reactive systems suffered so far from two main drawbacks. Fir ..."
Abstract

Cited by 22 (6 self)
 Add to MetaCart
(Show Context)
Reactive systems, proposed by Leifer and Milner, represent a metaframework aimed at deriving behavioral congruences for those specification formalisms whose operational semantics is provided by rewriting rules. Despite its applicability, reactive systems suffered so far from two main drawbacks. First of all, no technique was found for recovering a set of inference rules, e.g. in the socalled SOS style, for describing the distilled observational semantics. Most importantly, the efforts focussed on strong bisimilarity, tackling neither weak nor barbed semantics. Our paper addresses both issues, instantiating them on a calculus whose semantics is still in a flux: Cardelli and Gordon’s mobile ambients. While the solution to the first issue is tailored over our case study, we provide a general framework for recasting (weak) barbed equivalence in the reactive systems formalism. Moreover, we prove that our proposal captures the behavioural semantics for mobile ambients proposed by Rathke and Sobociński and by Merro and Zappa Nardelli.
Process Bisimulation via a Graphical Encoding
 IN: ICGT ‘06. VOLUME 4178 OF LNCS
, 2006
"... The paper presents a case study on the synthesis of labelled transition systems (ltss) for process calculi, choosing as testbed Milner’s Calculus of Communicating System (ccs). The proposal is based on a graphical encoding: each ccs process is mapped into a graph equipped with suitable interfaces, s ..."
Abstract

Cited by 20 (12 self)
 Add to MetaCart
The paper presents a case study on the synthesis of labelled transition systems (ltss) for process calculi, choosing as testbed Milner’s Calculus of Communicating System (ccs). The proposal is based on a graphical encoding: each ccs process is mapped into a graph equipped with suitable interfaces, such that the denotation is fully abstract with respect to the usual structural congruence. Graphs with interfaces are amenable to the synthesis mechanism based on borrowed contexts (bcs), proposed by Ehrig and König (which are an instance of relative pushouts, originally introduced by Milner and Leifer). The bc mechanism allows the effective construction of an lts that has graphs with interfaces as both states and labels, and such that the associated bisimilarity is automatically a congruence. Our paper focuses on the analysis of the lts distilled by exploiting the encoding of ccs processes: besides offering some technical contributions towards the simplification of the bc mechanism, the key result of our work is the proof that the bisimilarity on processes obtained via bcs coincides with the standard strong bisimilarity for ccs.
A Behavioural Congruence for Web services
 In Arbab, F., Sarjani, M., eds.: Fundamentals of Software Engineering, LNCS (To appear
, 2007
"... Abstract. Web services are emerging as a promising technology for the development of next generation distributed heterogeneous software systems. We define a new behavioural equivalence for Web services, based on bisimilarity and inspired by recent advances in the theory of reactive systems. The prop ..."
Abstract

Cited by 13 (6 self)
 Add to MetaCart
(Show Context)
Abstract. Web services are emerging as a promising technology for the development of next generation distributed heterogeneous software systems. We define a new behavioural equivalence for Web services, based on bisimilarity and inspired by recent advances in the theory of reactive systems. The proposed equivalence is compositional and decidable, and it provides a firm ground for enhanced behaviouraware discovery and for a sound incremental development of services and service compositions. 1
Deriving Labels and Bisimilarity for Concurrent Constraint Programming
, 2010
"... Abstract. Concurrent constraint programming (ccp) is a wellestablished model for concurrency that builds upon operational and algebraic notions from process calculi and firstorder logic. Bisimilarity is one of the central reasoning techniques in concurrency. The standard definition of bisimilarity ..."
Abstract

Cited by 12 (9 self)
 Add to MetaCart
(Show Context)
Abstract. Concurrent constraint programming (ccp) is a wellestablished model for concurrency that builds upon operational and algebraic notions from process calculi and firstorder logic. Bisimilarity is one of the central reasoning techniques in concurrency. The standard definition of bisimilarity, however, is not completely satisfactory for ccp since it yields an equivalence that is too fine grained. By building upon recent foundational investigations, we introduce a labelled w.r.t. the typical observational equivalence in ccp. This way we provide ccp with a new proof technique for ccp coherent with existing ones.
Abstract Semantics by Observable Contexts
, 2008
"... The operational behavior of interactive systems is usually given in terms of transition systems labeled with actions, which, when visible, represent both observations and interactions with the external world. The abstract semantics is given in terms of behavioral equivalences, which depend on the ac ..."
Abstract

Cited by 10 (4 self)
 Add to MetaCart
The operational behavior of interactive systems is usually given in terms of transition systems labeled with actions, which, when visible, represent both observations and interactions with the external world. The abstract semantics is given in terms of behavioral equivalences, which depend on the action labels and on the amount of branching structure considered. Behavioural equivalences are often congruences with respect to the operations of the language, and this property expresses the compositionality of the abstract semantics. A simpler approach, inspired by classical formalisms like λcalculus, Petri nets, term and graph rewriting, and pioneered by the Chemical Abstract Machine [1], defines operational semantics by means of structural axioms and reaction rules. Process calculi representing complex systems, in particular those able to generate and communicate names, are often defined in this way, since structural axioms give a clear idea of the intended structure of the states while reaction rules, which are often nonconditional, give a direct account of the possible steps. Transitions caused by reaction rules, however, are not labeled, since
Symbolic semantics revisited
, 2008
"... Symbolic bisimulations were introduced as a mean to define valuepassing process calculi using smaller, possibly finite labelled transition systems, equipped with symbolic actions. Similar ideas have been used for modeling with fewer transitions the input behavior of open and asynchronous πcalculu ..."
Abstract

Cited by 9 (5 self)
 Add to MetaCart
(Show Context)
Symbolic bisimulations were introduced as a mean to define valuepassing process calculi using smaller, possibly finite labelled transition systems, equipped with symbolic actions. Similar ideas have been used for modeling with fewer transitions the input behavior of open and asynchronous πcalculus. In this paper we generalize the symbolic technique and apply the resulting theory to these two cases, rederiving existing results. We also apply our approach to a new setting, i.e. open Petri nets, with the usual result of reducing input transitions. Our theory generalizes Leifer and Milner reactive systems by adding observations.
A coalgebraic theory of reactive systems
, 1999
"... In this report we study the connection between two well known models for interactive systems. Reactive Systems à la Leifer and Milner allow to derive an interactive semantics from a reduction semantics guaranteeing, semantics (bisimilarity). Universal Coalgebra provides a categorical framework where ..."
Abstract

Cited by 9 (1 self)
 Add to MetaCart
In this report we study the connection between two well known models for interactive systems. Reactive Systems à la Leifer and Milner allow to derive an interactive semantics from a reduction semantics guaranteeing, semantics (bisimilarity). Universal Coalgebra provides a categorical framework where bisimilarity can be characterized as final semantics, i.e., as the unique morphism to the final coalgebra. Moreover, if lifting a coalgebra to a structured setting is possible, then bisimilarity is compositional with respect to the lifted structure. Here we show that for every reactive system we can build a coalgebra. Furthermore, if bisimilarity is compositional in the reactive system, then we can lift this coalgebra to a structured coalgebra.
Compositional Specification of Web Services via Behavioural Equivalence: A Case Study
, 2007
"... Web services represent a promising technology for the development of distributed heterogeneous software systems. In this setting, a major issue is to establish whether two services can be used interchangeably in any context. This paper illustrates — through a concrete scenario from banking systems — ..."
Abstract

Cited by 7 (3 self)
 Add to MetaCart
(Show Context)
Web services represent a promising technology for the development of distributed heterogeneous software systems. In this setting, a major issue is to establish whether two services can be used interchangeably in any context. This paper illustrates — through a concrete scenario from banking systems — how a suitable notion of behavioural equivalence over Petri nets can be effectively employed for checking the correctness of service specifications and the replaceability of (sub)services.
On the Use of Behavioural Equivalences for Web Services’ Development
, 2008
"... Web services are emerging as a promising technology for the development of next generation distributed heterogeneous software systems. We define a new behavioural equivalence for Web services, based on bisimilarity and inspired by recent advances in the theory of reactive systems. The equivalence is ..."
Abstract

Cited by 7 (4 self)
 Add to MetaCart
Web services are emerging as a promising technology for the development of next generation distributed heterogeneous software systems. We define a new behavioural equivalence for Web services, based on bisimilarity and inspired by recent advances in the theory of reactive systems. The equivalence is compositional and decidable, and it provides a firm ground for enhanced behaviouraware discovery and for a sound incremental development of services and service compositions.