The analysis of the key performances of ControlNet

In order to evaluate the real time property, stability and deterministic of ControlNet fieldbus, a simple and effective transmission time delay model was proposed to analyze the characteristic of virtual token passing (VTP) mechanism. Then, the maximum transmission time delay in the scheduled part of network update time can be determined. According to the contribution of the transmission time delay to the network throughput, a new performance evaluation architecture, which includes the network efficiency, network utilization, packet loss rate and throughput, was given. The simulated results indicate ControlNet has good throughput and excellent real-time property in multicast mode when the traffic load is small, and the network efficiency is over 90%.