Enabling PROFINET devices to work in IoT: Characterization and requirements

The rise of Internet of Things (IoT) has impacted the industrial automation world. Traditional fleldbus and new fieldbus based on Real Time Ethernet (as PROFINET) have been challenged to include IoT solutions, whose real possibilities are still under evaluation. On the other hand, there are properties of industrial automation devices (e.g. robustness, "proven in use", explosion proof) that may be useful also in typical IoT scenarios (e.g. building automation). Therefore, the paper proposes a reversed approach, where a new architecture enables the use of existing, legacy, industry-grade devices (e.g. PROFINET Sensors, actuators, and Programmable Logic controllers - PLC) to be used across the Internet. In the proposed system, the PROFINET network can be put into work by means of transparent proxies that use IoT paradigms. The paper presents and discusses a set of basic requirements and a preliminary performance evaluation of a sample application. The results show that the 99-percentile of the transfer time (from proxy to proxy) in the proposed system is less than 100ms, and it is stable even varying the PROFINET cycle time.