Glossary
Programmable logic controller (PLC)
Also known as: SPS (German: speicherprogrammierbare Steuerung)
A programmable logic controller (PLC) is a ruggedised industrial computer that reads inputs from sensors and drives outputs such as motors and valves according to a control program.
By Thomas HeukerLast updated:
PLCs are the workhorses of industrial automation. Engineers program them from an engineering workstation; the PLC then runs that logic in a continuous scan cycle. For attackers, changing PLC logic or setpoints is the most direct way to affect a physical process — see the MITRE ATT&CK for ICS techniques T0843 Program Download and T0836 Modify Parameter. Monitoring engineering traffic to PLCs is therefore one of the highest-value OT SOC use cases.