An Overview of Time-Sensitive Communications for the Factory Floor

The state of the art for real-time factory-floor communications consists of a variety of protocols and technologies that aid in timely data exchange through the network. The majority of these are of a fieldbus type, running on a wired link like Ethernet. The choice of medium widely reflects the desire for high reliability. This attribute, reliability, is an indispensable condition for any industrial communications. Many industrial communication technologies exist, of which the most prominent are: PROFINET, EtherNet/IP, Sercos III, EtherCAT, and OPC UA. Time Sensitive Networking (TSN) is a relative newcomer in this arena, known for the strict synchronisation it maintains between communicating entities, among other things. This work presents and distinguishes between these various technologies, showing how they compare to one another, and also looking into how they may possibly coexist. The assessment can be used by African industries as they take the first steps in defining the factory-floor of the future, enabled by the Fourth Industrial Revolution.