Logic programming for real-time control of telecommunication switching systems

AbstractAn experiment using logic programming in the specification and implementation of a telecommunication switching system is reported, and one of the main modules in the system, a telephone-line controller, is described in detail as an illustrative example. The system is described in terms of transition relations in a labeled transition system. The programming language used is a variant of the parallel logic language PARLOG augmented with annotations to express timing constraints. The operational model of PARLOG is modified to handle time by allowing each goal-reduction process in a query to maintain its own logical clock, which can be read and set by the goal-reduction process itself. A metainterpreter is given to describe the operational behavior and an implementation scheme for the language