In: Billington, J.; Diaz, M.; Rozenberg, G.: Lecture Notes in Computer Science, Vol. 1605: Application of Petri Nets to Communication Networks, pages 93-130. Springer-Verlag, 1999.
Abstract: This paper presents a colored Petri net based modeling, simulation and analysis of the centralized architecture of the timed-token Fieldbus protocol. In such an architecture, the asynchronous traffic classes are served by using an emulation of a `circulate' timed-token mechanism, while the synchronous one is served by a centralized scheduling mechanism. The performance evaluation is concerned with two different policies of asynchronous bandwidth allocation. The first is based on static allocation scheme (SAS), and the second is based on a dynamic one (DAS), that uses the leftover bandwidth allocated to a specific station and adds it to the share of the following station dynamically. Considering a symmetric and asymmetric systems, four hierarchical timed colored Petri nets (HTCPNs) were developed, each corresponding to a specific system using either the SAS or the DAS. The simulation results show the superiority of the DAS over the SAS in improving the performance of the normal priority and time availability priority traffic classes in terms of increasing channel utilization, decreasing transfer delays and token delegation overheads.
Keywords: Fieldbus protocol, bandwidth allocation policies, colored Petri nets.
Back to the Petri Nets Bibliography