Findings on QoS Metrics of L3 Network Devices Intended for Future Factory Automation

Internetworking technologies have penetrated industrial automation for the last decade gaining enormous popularity. A new trend of network segmentation in automation networks has emerged together with the growing popularity and number of nodes in field. However, neither the Ethernet-based fieldbuses, nor existing network devices are tailored to routed (L3) real-time communication used for time-critical run-time data exchange. The paper presents an approach to delivering real-time communication across LAN segments with the use of existing L3 network devices. Firstly, the real-time requirements of industrial automation and the principles of QoS are presented. Secondly, a test bed designed for evaluation of QoS parameters of the given network devices is introduced. Finally, first findings on the influence of the L3 network devices on QoS parameters are shown.