Abstract

Engineers have used construction of models to investigate properties of 
designs, before implementations, for generations. This trend is gradually 
being transferred to the software engineering. Today UML is well 
established in the modelling of applications where the structure of data is 
the main concern, e.g. traditional office applications and applications for 
database access. During the process of creating and testing the models the 
designers gain insight which allow them to improve their designs and try 
different solutions before crucial design decisions are made.
Coloured Petri Nets and the tools Design/CPN and CPN Tools offers a 
supplement to the mainly data driven models of UML, and we will show 
examples of models where Coloured Petri Nets are used to capture essential 
behavioural properties of systems. We address important issues of the 
modelling process, such as: finding the right level of abstraction, how to 
structure large models and what not to model.
For the modelling to be successful it is equally important that we have 
rich formalisms, powerful computer tools, and skilled engineers. Only this 
combination will allow us to build the increasingly complex systems needed 
in the future.