Operational technology (OT) comprises hardware and software that monitor and control physical processes—such as PLCs, RTUs, HMIs, SCADA, and DCS—in manufacturing, utilities, transport, and buildings. Its assets include controllers, sensors, actuators, engineering workstations, and the networks linking them. OT depends on precise timing, reliable communications, and safe states; outages or incorrect commands can stop production or affect physical safety, even when little sensitive data is involved.
Security concerns arise where OT connects to enterprise networks, vendor remote-access paths, or internet-facing services. Legacy protocols and long-lived devices may lack authentication, encryption, logging, or practical patching options. A compromise could alter setpoints, inhibit alarms, or disrupt availability, but impact depends on process design and safeguards. Defenders typically segment control networks, restrict and monitor remote access, maintain asset and dependency inventories, use passive monitoring where active scanning is risky, and test recovery and safe manual operation. Vulnerability management must account for maintenance windows, vendor support, and safety validation rather than treating every patch like IT.