Qualitative and Quantitative Analysis of Mobile Systems

In this study we propose a uniform framework to carry out functional and performance analysis of mobile systems. In particular, we rely on a recent process calculus suitable to express mobility:-calculus. Since its semantics is given in SOS style, the behaviour of processes is conveniently represented through transition systems: directed and labelled graphs whose nodes are states of the system and whose arcs represent computational steps. Standard techniques to determine functional properties of processes like equivalence of diierent speciications, deadlocks detection and reachability analysis are available and extensively described in the literature. On the other hand, less space has been devoted to the study of quantitative aspects of systems in this framework. We here show how a transition system can be directly mapped into a continuous time Markov chain on which quantitative aspects are studied with standard techniques. The probabilistic information needed to build the generator matrix of the Markov chain are inserted in the syntax of the calculus yielding a stochastic extension of-calculus. As an application of this framework we consider here the Internet protocol (IP) for mobility support.