A Denotational Model for Probabilistic and Nondeterministic Processes

. In this paper we present an algebraic model for the description of probabilistic and nondeterministic processes: PNAL (Probabilistic and Nondeterministic Algebraic Language), an extension of EPL, defined by Matthew Hennessy, including a probabilistic choice operator. An operational semantics and a testing semantics for the language are presented. A denotational semantics for the finite subset of the language, PNAL f , is proposed. Finally, we provide two results: equivalence between nondeterministic processes in finite EPL is preserved in PNAL f , and denotational semantics is fully abstract with respect to the testing semantics. 1 Introduction In the eighties, the fundamentals of process algebras were firmly established thanks to the works of Hoare, Milner, Bergstra, Hennessy et al. In these works only qualitative aspects of concurrent systems were considered. Later quantitative aspects have been studied by several researchers. Thus, several extensions to classical process algebra ..