Performance evaluation of four field buses

In this article, a comparative study of the performance of the CAN, the Profibus-DP, the Profibus-FMS and the Modbus Plus field buses is carried out. An analytical approach is adopted to evaluate the performance of the networks in an event-driven system in terms of throughput and responsiveness. Cyclic data exchanges are analysed in a deterministic way in terms of the bandwidth consumed. Finally, we focus on the behaviour of systems with both cyclic and acyclic interchanges. As long as it is critical to ensure the bandwidth assigned to cyclic traffic, we analyse the effect that the bandwidth consumed by the cyclic traffic has on the throughput and responsiveness obtained when only acyclic traffic is considered.