[Best way to uniquely identify a UniStream® 15.6" PLC]

That makes sense but, unfortunately, the `System.CPU HW Version.Serial Number` tag just display "Serial Number". So it does not uniquely identify a PLC. I would have expected the same number as the one printed on the sticker at the back of the panel or the CPU module.

This is a screen shot taken with VNC Viewer (other ID tags have been blurred):

[Best way to uniquely identify a UniStream® 15.6" PLC]

What is the best way to uniquely identify a UniStream® 15.6" PLC with software?

Several PLCs are connected to a network with Ethernet cables and they are monitored/controlled by another equipment. I would need to be able to uniquely identify every connected PLCs to make sure, for example, that a PLC connected to given IP address is the expected one.

I have read on ASCII String to MI? that the best way to do that was to retrieve the CPU MAC address. Is it still the best way today?