In this paper, we enrich the π-calculus with an operator for confidentiality (hide), whose main effect is to restrict the access to the object of the communication, thus representing confidentiality in a natural way. The hide operator is meant for local communication, and it differs from new in that it forbids the extrusion of the name and hence has a static scope. Consequently, a communication...

For cell-biological processes, it is the complex interaction of their biochemical components, affected by both stochastic and spatial considerations, that create the overall picture. Formal modeling provides a method to overcome the limits of experimental observation in the wetlab by moving to the abstract world of the computer. The limits of the abstract world again depend on the expressivenes...

We use the -calculus to model the evolution of biochemical systems, taking advantage of their similarities with global computation applications. First, we present a reduction semantics for the -calculus from which causality and concurrency can be mechanically derived. We prove that our semantics agrees with the causal de-nitions presented in the literature. We also extend our semantics to model...

Action structures are proposed as a variety of algebra to underlie concrete models of concurrency and interaction. An action structure is equipped with composition and product of actions, together with an indexed family of abstractors to allow parametrisation of actions, and a reaction relation to represent activity. The eight axioms of an action structure make it an enriched strict monoidal ca...

An account of the basic theory of confluence in the 1r-calculus is presented, techniques for showing confluence of mobile systems are given, and the utility of some of the theory presented is illustrated via an analysis of a distributed algorithm. 1 I n t r o d u c t i o n Confluence arises in a variety of forms in computation theory. It was first studied in the context of concurrent systems by...

This paper proposes two semantics of a probabilistic variant of the π-calculus: an interleaving semantics in terms of Segala automata and a true concurrent semantics, in terms of probabilistic event structures. The key technical point is a use of types to identify a good class of non-deterministic probabilistic behaviours which can preserve a compositionality of the parallel operator in the eve...

Dynamic compartments with mutable configurations and variable volumes are of basic interest for the stochastic modeling of biochemistry in cells. We propose a new language to express dynamic compartments that we call the imperative π-calculus. It is obtained from the attributed π-calculus by adding imperative assignment operations to a global store. Previous approaches to dynamic compartments a...

The problem of finding a fully abstract model for the polymorphic π-calculus was stated in Pierce and Sangiorgi’s work in 1997 and has remained open since then. In this paper, we show that a slight variant of their language has a direct fully abstract model, which does not depend on type unification or logical relations. This is the first fully abstract model for a polymorphic concurrent langua...

The chi calculus proposed several years ago enjoys some properties unknown from the experience with pi calculus, one of which is the ability to model concurrent computation without the use of prefix combinator. The atomic chi calculus studied in this paper is obtained from polyadic chi calculus by leaving out the prefix operator. This omission is impossible in the pi framework because it would ...

The spi calculus is an extension of the pi calculus with constructs for encryption and decryption. This paper develops the theory of the spi calculus, focusing on techniques for establishing testing equivalence , and applying these techniques to the proof of authenticity and secrecy properties of cryptographic protocols. The idea of controlling communication by capabilities underlies both the p...