A Distributed Abstract Machine for Boxed Ambient Calculi

Abstract

Abstract. Boxed ambient calculi have been used to model and reason about a wide variety of problems in mobile computing. Recently, several new variants of Boxed Ambients have been proposed, which seek to improve on the original calculus. In spite of these theoretical advances, there has been little research on how such calculi can be correctly implemented in a distributed environment. This paper bridges a gap between theory and implementation by defining a distributed abstract machine for a variant of Boxed Ambients with channels. The abstract machine uses a list semantics, which is close to an implementation language, and a blocking semantics, which leads to an efficient implementation. The machine is proved sound and complete with respect to the underlying calculus. A prototype implementation is also described, together with an application for tracking the location of migrating ambients. The correctness of the machine ensures that the work done in specifying and analysing mobile applications is not lost during their implementation.

A taxonomy of process calculi for distribution and mobility

“…More recently, calculi for mobility have also been the workbench of orthogonal research lines, like the development of efficient implementations of new programming paradigms [20,21,46,50] and of easy-to-handle proof-techniques for proving behavioural properties of systems [8,27,33,35,37]. From the practical side, we would need real-life applications where the distinctive features of such formalisms are essential.…”

Pict correctness revisited

“…Their correctness is proven in terms of bisimilary that does not apply to our setting, since Pict implementation makes deterministic choice and PAM reductions do not match all π -calculus reductions. Implementations that consider scheduling of processes are given in [15,10]. In [15], a soundness property is given, similar to the one given for Pict in [19].…”

“…There have been several recent papers devoted to the formal description of implementations of process calculi based on the π-calculus or the Ambient calculus. In addition to Pict, one can notably cite the Jocaml distributed implementation of the Join calculus [6,5], the Join calculus implementation of Mobile Ambients [7], Nomadic Pict [22,20], the abstract machine for the M-calculus [10], the Fusion Machine [8], the PAN and GCPAN abstract machines for Safe Ambients [11,12], the CAM abstract machine for Channel Ambients [15] and the abstract machine for the Kell calculus [1]. Most of these works [7,22,20,10,8,11,12,15,1] deal with distributed implementations of calculi, rather than local implementation of concurrent processes like in Pict.…”

Probabilistic Mobile Ambients

“…The main advantage of MA, with respect to other calculi, is the simple constructs of the language and the inherent hierarchical structure of the processes. In the community of programming languages, MA has already become very popular [23][24][25][26][27][28][29][30] to describe many issues, from access control to security protocols, from systems biology [31] to implementation of distributed languages [32]. Yet, quantitative aspects of computation in MA have only been studied in [31,15] within the boundaries of continuous-time Markov chains.…”