ICS components communicate with each other using different network protocols and standards. OT-specific protocols are used in addition to protocols and standards from office IT, such as Ethernet, TCP/ IP, WLAN, or GSM. Not all of these elements have been developed from the perspective of information security, and some thus offer limited security mechanisms (or none at all). Information is frequently transmitted as plain text without means of authentication or securing its integrity.

An attacker with access to a given network could read or change the contents of communications and thus influence processes—by faking sensor data or forging control commands, for example. This applies in particular to protocols that are used for communication via freely accessible areas, such as for radio protocols or as part of location networking.