Informal Introduction to Coloured Petri Nets

Abstract

High-level nets, such as Coloured Petri Nets (CP-nets) and Predicate/ Transition Nets (Pr/T-nets), are now in widespread use for many different practical purposes. A selection of references to papers describing industrial applications can be found in the bibliographical remarks of Chap. 7. The main reason for the great success of these kinds of net models is the fact that they have a graphical representation and a well-defined semantics allowing formal analysis. The step from low-level Petri nets to high-level nets can be compared to the step from assembly languages to modern programming languages with an elaborated type concept. In low-level nets there is only one kind of token and this means that the state of a place is described by an integer (and in many cases even by a boolean value). In high-level nets, each token can carry complex information or data (which, e.g., may describe the entire state of a process or a data base).