A brief survey and synthesis of the roles of time in petri nets

Petri nets augmented with time are interesting models which can be used for the modelling and analysis of a wide range of concurrent discrete-event systems. In this paper, the nature of the semantics of different approaches to incorporating time in Petri nets is illustrated by examples. The paper considers the critical roles of conflict, confusion and concurrence in the formulation of execution policies. Several different methods for the analysis of timed Petri net models are also discussed. The paper then introduces a timed Petri net structure which incorporates all the other structures described.