OPC

An industry standard for communicating with/between devices, servers and clients. This is open and non-patented and is a basis of “industry 4.0”. See https://opcfoundation.org/ . Historical versions are OPC-DA (windows only, deprecated) and OPC-UA (unified architecture). The implementations of OPC-UA come as “toolkits” which are also commercially available.

One of the major communication protocols used in WinCC-OA for the experiments

Open Process Control