I started my IT career in the 1980s with machine data collection and analysis for the United States Air Force. Later, I was the principal device driver writer for Bradley Ward, Inc. who had a similar concept of an Interface layer that standardized various PLC-type devices to a "software bus" that interfaced them into the main SCADA system. I wrote drivers for numerous devices including Allen-Bradley PLCs, TI PLCs, Mettler scales, and several proprietary devices for various customers.
It sounds like you will be including some hardware in your device standardization layer, and the devices are to interface to that based on standard protocols. If I am reading this correctly, the protocols will be parameterized, and your "device profile" will contain the parameters for that device. These might include the port number, device id, number of sensors, each sensor id, etc.
Although your project description doesn't mention it, I was also the writer for the Database Interfaces (on the same structure) that the SCADA system used for data logging. I wrote the interfaces for Oracle, Allbase, flat file formats, and a high-speed binary format I designed myself.
I look forward to chatting about the project with you over PM.
Murray