Behaviour Abstraction for Communicating Sequential Processes

Article type: Research Article

Authors: Koutny, Maciej | Pappalardo, Giuseppe

Affiliations: Department of Computer Science, University of Newcastle, Newcastle upon Tyne NE1 7RU, U.K. | Dipartimento di Matematica e Informatica, Università di Catania, I-95125 Catania, Italy

Abstract: We investigate the notion that a system is an acceptable implementation of another base or target system, in the case that the two systems (or processes) have different interfaces. For instance, the base processes can be thought of as specifications, or ideal processes operating in an error-free environment, while the implementations model their actual realisations, operating in an error-prone environment and possibly employing a variety of fault-tolerant techniques. Using the CSP model, we relate implementations and base systems in terms of their observable behaviours. We obtain two fundamental results, viz. realisability and compositionality. The former ensures that implementations may be put to good use, while the latter guarantees that a target composed of several connected subsystems may be implemented by connecting their respective implementations.

Keywords: Theory of parallel and distributed computation, behaviour abstraction, communicating sequential processes, compositionality

Journal: Fundamenta Informaticae, vol. 48, no. 1, pp. 21-54, 2001