Combining process modelling methods

This paper examines two modelling paradigms, namely Hoare’s Communicating Sequential Processes (CSP) and a subset of Role Activity Diagrams (RADs) and shows how they can be combined to give a new approach to process modelling. We examine the two notations by reference to processes from two different business domains. For each domain, we transform a RAD model (by way of methodical mapping) to arrive at an equivalent formal CSP model. The latter is then explored using a stepper, which allows for process simulation by executing the model. The paper suggests that by providing a mapping between these notations we gain the accessibility of a well understood user-facing modelling paradigm, (RADs), whilst retaining the formality of CSP. This provides us not only with the advantages of understandable user-facing models, for process elicitation and presentation, but also gives us the ability to experiment with (by process simulation) the effects of process change.