Real-time Ethernet - a solution for all communication-related problems within a digital production print line?

In the industry there is a growing trend to use real-time Ethernet for factory communication. In this case study from the digital print industry a new communication standard is selected to host an automation protocol. It would have been a natural choice to migrate to a real-time-Ethernet derivative. However, after a research project an industry consortium chose not to adopt real-time-Ethernet but migrate to a two-cable approach that separates the data to be communicated in terms of their real-time requirements although from a technical point of view, real-time Ethernet would have been a viable alternative. This paper explains the background of this decision and it further shows that incorporating only one physical hardware connection combining several types of information not necessarily simplifies an implementation.