Communicating sequential processes for distributed constraint satisfaction

Abstract

CSPCONS is a programming language that supports program execution over multiple Prolog processes with constraints. The language is an extended version of C sp-ii, a version of Prolog that supports channel-based communicating processes and TCP/IP communication, that is based on the CSP model introduced by Hoare. C spcons inherits all the advanced features of C sp-ii and extends it by introducing constraint solving capabilities to the processes. In C spcons each Prolog process has one or more solvers attached and each solver is independent from the others, following the original C sp-ii model, thus resulting to a communicating sequential constraint logic programming system. Such a model can facilitate greatly the implementation of distributed CLP applications. This paper describes the original C sp-ii system along with details of the extensions that resulted to the C spcons system and presents an example demonstrating the applicability of the system to distributed constraint satisfaction problems.