Stochastic Process Algebras: a New Approach to Performance Modeling

In this chapter we present an introduction to the novel approach to performance modeling provided by stochastic process algebras (SPA). Like queueing networks and stochastic Petri nets, and their variants, these formal languages can be regarded as high-level model specification languages for low-level stochastic models. The advantages of SPAs are that they incorporate the attractive features of process algebras and thus bring to the area of performance modeling several attributes which are not offered by the existing formalisms. Perhaps the most important such feature is the compositionality which is inherent in the models and can be exploited during their analysis. Throughout this chapter we will present several simple examples which illustrate this and several other aspects of the SPA approach to performance modeling