Industrial control systems (ICS) are the computers, networks, programmable controllers, sensors, and actuators that monitor and operate physical processes. They include supervisory control and data acquisition (SCADA), distributed control systems, and plant-floor automation in sectors such as manufacturing, energy, transport, and water. Their critical assets are the control logic and process data, while their dependencies include engineering workstations, operator consoles, industrial protocols, communications links, and sometimes connections to enterprise or remote-access systems.
ICS security must protect availability, process integrity, and safety as well as confidentiality. Unauthorized changes to controller logic, compromised remote access, vulnerable engineering software, or disruption of communications can produce unsafe conditions or halt operations, though impact depends on the process and its safeguards. Defenses commonly include accurate asset inventories, network segmentation, tightly controlled and monitored remote access, secure configuration, tested backups of control logic, and vulnerability management that accounts for maintenance windows and the risks of disrupting real-time systems. Incident response may require isolating affected equipment while preserving safe operation or manual fallback.