AC800M / 800xA Cyber security
I have an Siemens Scada and siemens contoller on its own ethernet network. This network has a remote connection via VPN and WEB to an external services supplier.
From an AC800M controller (connected to its 800xA network, phisicaly separated from the previous Siemens network), I need to collect some tags value from this Siemens Control System using a serial connection and a CI853 board installed on PM864 controller.
From a cyber security point of view, a serial connection made in this way between the two control system (ABB & Siemens), is safe or I need to implement some more security system like firewall or other software/hardware device to prevent any malware/virus attack from the Siemens network ?