Discrete Event Systems
Prof R M Thomas
A discrete event system is a mathematical model of a system (such as computational device) that communicates with its environment by atomic actions (called events). For example, a user of the system pressing a button could send a signal to a controller. These events are assumed to be discrete in the sense that they occur instantaneously (as opposed to over a period of time).
The module will present an overview of various modelling and analysis techniques for discrete event systems. We start by looking at sequential systems (where no two events can occur simultaneously). Systems of this kind will be modelled by finite automata. This class is then extended to allow for events occurring simultaneously; these are modelled by Petri nets. Subsequently, we will study techniques that allow us to extract quantitative information about the behaviour of systems. This gives rise to the class of probabilistic systems (where we assume that a certain event occurs with a given probability) and we can then estimate the likelihood of situations such as system failure. Included in this section is an introduction to queuing theory.