I have a SCADA system that operates in its own network without any external connections. The problem was that this meant I couldn't send alarm messages to the outside world to notify the on-call team. That meant I had to come up with something.
I send the alarms via an RS-232 interface to another server located in a different network, which runs a Python script that receives the alarms, formats them, and then sends them to our alarm distributor (Divera) via a GET request.
Because modern computers no longer have an RS-232 interface, an external COM port is used. Link
To ensure that data can only be sent out and not received, only the transmit pin was soldered to one side of the RS-232 connection cable and only the receive pin to the other side.
ToDo:
- upload Graphic,
- upload Python script,