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arXiv · 1601.01725

On Hierarchical Communication Topologies in the pi-calculus

Emanuele D'Osualdo·C. -H. Luke Ong
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Abstract

This paper is concerned with the shape invariants satisfied by the communication topology of {\pi}-terms, and the automatic inference of these invariants. A {\pi}-term P is hierarchical if there is a finite forest T such that the communication topology of every term reachable from P satisfies a T-shaped invariant. We design a static analysis to prove a term hierarchical by means of a novel type system that enjoys decidable inference. The soundness proof of the type system employs a non-standard view of {\pi}-calculus reactions. The coverability problem for hierarchical terms is decidable. This is proved by showing that every hierarchical term is depth-bounded, an undecidable property known in the literature. We thus obtain an expressive static fragment of the {\pi}-calculus with decidable safety verification problems.

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Emanuele D'Osualdo, C. -H. Luke Ong. 2016-01-07. On Hierarchical Communication Topologies in the pi-calculus. https://doi.org/10.1007/978-3-662-49498-1_7

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