In 10 , an algebra for timed automata has been introduced. In this article, we introduce a syntactic characterisation of nite timed automata in terms of that process algebra. We show that regular processes, i.e., processes de ned using nitely many guarded recursive equations, are as expressive as nite timed automata. The proof uses only the axiom system and unfolding of recursive equations. Since the proofs are basically algorithms, we also provide an e ective method to translate from one model into the other. A remarkable corollary of these proofs is that regular recursive speci cations may need one clock less than timed automata in order to represent the same process. 1991 Mathematics Subject Classi cation: 68Q45, 68Q55, 68Q60. 1991 CR Categories: D.3.1, F.3.1, F.3.2, F.4.3.
Pedro R. D'Argenio