International Conference on Concurrency Theory 

About: International Conference on Concurrency Theory is an academic conference. The conference publishes majorly in the area(s): Concurrency & Decidability. Over the lifetime, 1317 publications have been published by the conference receiving 44685 citations.

The Linear Time - Branching Time Spectrum II

Abstract: This paper studies semantic equivalences and preorders for sequential systems with silent moves, restricting attention to the ones that abstract from successful termination, stochastic and real-time aspects of the investigated systems, and the structure of the visible actions systems can perform. It provides a parameterized definition of such a preorder, such that most such preorders and equivalences found in the literature are obtained by a suitable instantiation of the parameters. Other instantiations yield preorders that combine properties from various semantics. Moreover, the approach shows several ways in which preorders that were originally only considered for systems without silent moves, most notably the ready simulation, can be generalized to an abstract setting, and how preorders that were originally only considered for for systems without divergence, such as the coupled simulation, can be extended to divergent systems. All preorders come with—or rather as—a modal characterization, and when possible also a relational characterization. The paper concludes with some pros and cons of the preorders.

Reachability Analysis of Pushdown Automata: Application to Model-Checking

Abstract: We apply the symbolic analysis principle to pushdown systems. We represent (possibly infinite) sets of configurations of such systems by means of finite-state automata. In order to reason in a uniform way about analysis problems involving both existential and universal path quantification (such as model-checking for branching-time logics), we consider the more general class of alternating pushdown systems and use alternating finite-state automata as a representation structure for sets of their configurations. We give a simple and natural procedure to compute sets of predecessors using this representation structure. We incorporate this procedure into the automata-theoretic approach to model-checking to define new model-checking algorithms for pushdown systems against both linear and branching-time properties. From these results we derive upper bounds for several model-checking problems as well as matching lower bounds.

A Calculus of Mobile Agents

Abstract: We introduce a calculus for mobile agents and give its chemical semantics, with a precise definition for migration, failure, and failure detection Various examples written in our calculus illustrate how to express remote executions, dynamic loading of remote resources and protocols with mobile agents We give the encoding of our distributed calculus into the join-calculus

Types for dyadic interaction

Abstract: We formulate a typed formalism for concurrency where types denote freely composable structure of dyadic interaction in the symmetric scheme. The resulting calculus is a typed reconstruction of name passing process calculi. Systems with both the explicit and implicit typing disciplines, where types form a simple hierarchy of types, are presented, which are proved to be in accordance with each other. A typed variant of bisimilarity is formulated and it is shown that typed β-equality has a clean embedding in the bisimilarity. Name reference structure induced by the simple hierarchy of types is studied, which fully characterises the typable terms in the set of untyped terms. It turns out that the name reference structure results in the deadlock-free property for a subset of terms with a certain regular structure, showing behavioural significance of the simple type discipline.

A temporal calculus of communicating systems

Abstract: In this paper, we introduce a calculus of communicating systems which allows for the expression and analysis of timing constraints, for example as is important for real-time processes. We present the language, along with its formal semantics, and derive algebraic laws for reasoning about processes in the language. Though the core language is simple, we show that the language has several powerful derived operators which we demonstrate to be useful in several examples.