## Reactive Systems, Barbed Semantics, and the Mobile Ambients

Citations: | 15 - 6 self |

### BibTeX

@MISC{Bonchi_reactivesystems,,

author = {Filippo Bonchi and Fabio Gadducci and Giacoma Valentina Monreale},

title = {Reactive Systems, Barbed Semantics, and the Mobile Ambients },

year = {}

}

### OpenURL

### Abstract

Reactive systems, proposed by Leifer and Milner, represent a meta-framework 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 so-called 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.

### Citations

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- 1989
(Show Context)
Citation Context ...tion formalisms (Petri nets [4,5], logic programming [2], etc.) as reactive systems, either hoping to recover the standard observational equivalence, whenever such a behavioural semantics exists (CCS =-=[6]-=-, pi-calculus [7], etc.), or trying to distill a meaningful semantics. The results are not yet fully satisfactory. On the one-side, bisimilarity via minimal contexts is usually too fine-grained. On th... |

1286 | A structural approach to operational semantics
- Plotkin
- 1981
(Show Context)
Citation Context ... ambient of the process exiting from an ambient provided by the environment, while in the rule Out both ambients are provided by the environment. The LTS D does not conform to the so-called SOS style =-=[15]-=-: indeed, the premises of the inference rules are just constraints over the structure of the process, as typical of the LTSs distilled by IPOs. In the next section we propose an alternative, yet equiv... |

809 | Mobile Ambients
- Cardelli, Gordon
- 1998
(Show Context)
Citation Context ...table case studies. To this end, we instantiate our proposal over a calculus whose observational semantics is still in a flux, namely, the calculus of mobile ambients, proposed by Cardelli and Gordon =-=[9]-=-. We proceed as follows. First of all, we consider a minimal context semantics for ambients, as distilled in [10] by means of a graphical encoding. Another drawback of reactive systems is that such di... |

587 |
Communicating and Mobile Systems: the π-Calculus
- Milner
- 1999
(Show Context)
Citation Context ...Petri nets [4,5], logic programming [2], etc.) as reactive systems, either hoping to recover the standard observational equivalence, whenever such a behavioural semantics exists (CCS [6], pi-calculus =-=[7]-=-, etc.), or trying to distill a meaningful semantics. The results are not yet fully satisfactory. On the one-side, bisimilarity via minimal contexts is usually too fine-grained. On the other side, sat... |

219 | Barbed bisimulation, in
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- 1992
(Show Context)
Citation Context ... semantics. Intuitively, since in weak semantics the observer can not check for the occurrence of reductions, all systems are observationally equivalent. Barbs were introduced by Milner and Sangiorgi =-=[8]-=- for addressing this kind of problem. Intuitively, a barb is just a predicate on the states of a system, and barbed equivalences add the check of such predicates in the bisimulation game. The flexibil... |

139 | On reduction-based process semantics - Honda, Yoshida - 1995 |

116 | R.: Deriving bisimulation congruences for reactive systems
- Leifer, Milner
(Show Context)
Citation Context ...rmalism. Moreover, we prove that our proposal captures the behavioural semantics for mobile ambients proposed by Rathke and Sobociński and by Merro and Zappa Nardelli. 1 Introduction Reactive systems =-=[1]-=- were proposed by Leifer and Milner as an abstract formalism for specifying the dynamics of a computational device. Indeed, the usual specification technique is based on a reduction system: a set, rep... |

61 | B.: Deriving bisimulation congruences in the DPO approach to graph rewriting with borrowed contexts
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- 2006
(Show Context)
Citation Context ...e are quite pleased by the parametric structure of the rules that we obtained, and we hope that we will be able to lift it to the instance of RPO adopted in graph rewriting, namely, borrowed contexts =-=[13]-=-. Finally, as discussed in Section 6, we recall that an alternative, labelled characterization of the strong reduction barbed congruence is presented in [11]. Rathke and Sobociński use there the stand... |

58 | A hierarchy of equivalences for asynchronous calculi
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(Show Context)
Citation Context ...r opinion that ∼BS is more appropriate, in order to model concurrent interactive systems embedded in an environment that continuously changes. And while in several formalisms the two notions coincide =-=[22]-=-, for MAs the standard behavioural equivalence ∼ = (Definition 7) is clearly an instance of ∼BS . Most importantly, though, barbed saturated bisimilarity can be efficiently characterized through the I... |

56 |
Bigraphs and transitions
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- 2003
(Show Context)
Citation Context ... Barbed Semantics for Reactive Systems Several attempts were made to encode specification formalisms (Petri nets [4,5], logic programming [2], CCS [16,17], λ-calculus [18,19], asynchronous π-calculus =-=[20]-=-, fusion calculus [21], etc.) as RSs, either hoping to recover the standard observational equivalences, whenever such a behavioural semantics exists (CCS [6], π-calculus [7], etc.), or trying to disti... |

50 | Pure bigraphs: structure and dynamics
- Milner
- 2006
(Show Context)
Citation Context ...CA Q.282 F. Bonchi, F. Gadducci, and G.V. Monreale 5 Barbed Semantics for Reactive Systems Several attempts were made to encode specification formalisms (Petri nets [4,5], logic programming [2], CCS =-=[16,17]-=-, λ-calculus [18,19], asynchronous π-calculus [20], fusion calculus [21], etc.) as RSs, either hoping to recover the standard observational equivalences, whenever such a behavioural semantics exists (... |

36 | P.: Reactive systems over cospans
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- 2005
(Show Context)
Citation Context ...]. The inference rules describing this LTS are obtained from an analysis of a LTS over (processes as) graphs, derived by the borrowed context mechanism [13], which is an instance of the theory of RSs =-=[14]-=-. The labels of the transitions are unary contexts, i.e., terms of the extended syntax with a hole −. Note that they are minimal contexts, that is, they represent the exact amount of context needed by... |

33 | Bigraphs for Petri Nets
- Milner
- 2004
(Show Context)
Citation Context ... be matched by any context. They capture saturated semantics, yet slashing the number of transitions that need to be checked. Several attempts were made to encode specification formalisms (Petri nets =-=[4,5]-=-, logic programming [2], etc.) as reactive systems, either hoping to recover the standard observational equivalence, whenever such a behavioural semantics exists (CCS [6], pi-calculus [7], etc.), or t... |

28 | Saturated semantics for reactive systems
- Bonchi, König, et al.
- 2006
(Show Context)
Citation Context ...ntified in [1] by the categorical notion of relative pushout: the resulting strong bisimilarity is a congruence, even if it often does not coincide with the saturated one. Semi-saturated equivalences =-=[2,3]-=- were introduced for recovering saturated semantics. The bisimulation game becomes asymmetric, and a minimal context may be matched by any context. They capture saturated semantics, yet slashing the n... |

23 | A congruence for Petri nets
- Sassone, Sobocinski
- 2005
(Show Context)
Citation Context ... be matched by any context. They capture saturated semantics, yet slashing the number of transitions that need to be checked. Several attempts were made to encode specification formalisms (Petri nets =-=[4,5]-=-, logic programming [2], etc.) as reactive systems, either hoping to recover the standard observational equivalence, whenever such a behavioural semantics exists (CCS [6], pi-calculus [7], etc.), or t... |

18 |
Behavioral theory for mobile ambients
- Merro, Nardelli
- 2005
(Show Context)
Citation Context ...le ambients do274 F. Bonchi, F. Gadducci, and G.V. Monreale capture the strong and weak barbed congruences for the calculus, as proposed by Rathke and Sobociński [11] and by Merro and Zappa Nardelli =-=[12]-=-, respectively. The paper is organized as follows. Section 2 recalls the basic notions of reactive systems, while Section 3 similarly introduces the main definitions concerning mobile ambients. Sectio... |

17 | B.: Process bisimulation via a graphical encoding
- Bonchi, Gadducci, et al.
(Show Context)
Citation Context ...CA Q.282 F. Bonchi, F. Gadducci, and G.V. Monreale 5 Barbed Semantics for Reactive Systems Several attempts were made to encode specification formalisms (Petri nets [4,5], logic programming [2], CCS =-=[16,17]-=-, λ-calculus [18,19], asynchronous π-calculus [20], fusion calculus [21], etc.) as RSs, either hoping to recover the standard observational equivalences, whenever such a behavioural semantics exists (... |

16 |
Local bigraphs and confluence: Two conjectures: (extended abstract
- Milner
(Show Context)
Citation Context ... F. Gadducci, and G.V. Monreale 5 Barbed Semantics for Reactive Systems Several attempts were made to encode specification formalisms (Petri nets [4,5], logic programming [2], CCS [16,17], λ-calculus =-=[18,19]-=-, asynchronous π-calculus [20], fusion calculus [21], etc.) as RSs, either hoping to recover the standard observational equivalences, whenever such a behavioural semantics exists (CCS [6], π-calculus ... |

16 | P.: Semantic Barbs and Biorthogonality - Rathke, Sassone, et al. - 2007 |

14 | Deriving structural labelled transitions for mobile ambients
- Rathke, Sobocinski
- 2008
(Show Context)
Citation Context ...ate is unobservable, therefore in order to take this phenomenon into account they propose a modification of the usual definition of bisimulation. On the contrary, Rathke and Sobociński use instead in =-=[11]-=- the ordinary bisimilarity for characterizing the strong reduction barbed congruence. However, they are forced to add a set of what they call Honda-Tokoro rules, in order to account for the same pheno... |

14 | Reactive systems over directed bigraphs
- Grohmann, Miculan
- 2007
(Show Context)
Citation Context ...Reactive Systems Several attempts were made to encode specification formalisms (Petri nets [4,5], logic programming [2], CCS [16,17], λ-calculus [18,19], asynchronous π-calculus [20], fusion calculus =-=[21]-=-, etc.) as RSs, either hoping to recover the standard observational equivalences, whenever such a behavioural semantics exists (CCS [6], π-calculus [7], etc.), or trying to distill a meaningful semant... |

9 | 2008): Abstract Semantics by Observable Contexts
- Bonchi
(Show Context)
Citation Context ...ntified in [1] by the categorical notion of relative pushout: the resulting strong bisimilarity is a congruence, even if it often does not coincide with the saturated one. Semi-saturated equivalences =-=[2,3]-=- were introduced for recovering saturated semantics. The bisimulation game becomes asymmetric, and a minimal context may be matched by any context. They capture saturated semantics, yet slashing the n... |

7 | G.V.: Labelled transitions for mobile ambients (as synthesized via a graphical encoding
- Bonchi, Gadducci, et al.
- 2009
(Show Context)
Citation Context ...ill in a flux, namely, the calculus of mobile ambients, proposed by Cardelli and Gordon [9]. We proceed as follows. First of all, we consider a minimal context semantics for ambients, as distilled in =-=[10]-=- by means of a graphical encoding. Another drawback of reactive systems is that such distilled semantics are usually not in a standard form. So, we propose an alternative, yet equivalent presentation ... |

1 | M.: RPO, second-order contexts, and λ-calculus - Gianantonio, Honsel, et al. - 2008 |