DEMON (Design Methods Based on Nets) Report, DSI (Dipartimento di Scienze dell'Informazione, Università degli Studi di Milano, Italy), April 1991.
Abstract: In this paper basic Petri net models are re-viewed. Their difficulties in modelling real systems are analyzed. In order to overcome these difficulties, the basic models are extended. This implies a basic mechanims of communication, whereby the holding of a transmitting condition lets the receiving events fire, whenever they have concession. The corresponding token rule is suggested, leading itself to a natural extension of the notion of Petri nets, where there is a communication between different nets modelling parts of a single system. The proposed extensions fit with a general movement towards object orientation in modelling complex concurrent systems.
Keywords: communicating net(s); extended net; object oriented modelling (of) concurrent systems.