An Asynchronous Process Algebra withMultiple

In this paper we introduce a novel approach to the speciication of real-time behaviour with process algebras. In contrast to the usual pattern, involving a xed, measurable, and global notion of time, we suggest to represent real-time constraints indirectly through uninterpreted clocks enforcing broadcast synchronization between processes. Our approach advocates the use of asynchronous process algebras, which admit the faithful representation of nondeterministic and distributed computations. Technically, we present a non-trivial extension of the Calculus of Communicating Systems CCS Mil89a] by multiple clocks with associated timeout and clock ignore operators. We illustrate the exibility of the proposed process algebra, called PMC, by presenting examples of rather diierent nature. The timeout operators generalize the timeout of ATP NS90] to multiple clocks. The main technical contribution is a complete axiomatization of strong bisim-ulation equivalence for a class of nite-state processes and a complete axiom-atization of observation congruence for nite processes.