Supervisory Control and Data Acquisition (SCADA)

SCADA is a class of software and systems that gathers real-time data from PLCs, RTUs and other field devices, presents it to operators and lets them supervise and command processes spread across a plant or a wide geographic area.

A SCADA system typically comprises field controllers such as PLCs and remote terminal units, a communication network, one or more servers that poll or subscribe to field data, and operator workstations running HMI graphics. The servers maintain a real-time database of tags, raise alarms, log events and record trends, often in a process historian. Operators monitor the process and send supervisory commands, such as setpoint changes or start and stop requests, while time-critical control remains in the field controllers.

SCADA originated in utilities and remains central to electricity transmission and distribution, water and wastewater networks, oil and gas pipelines and rail, where assets are geographically dispersed. In manufacturing, the same supervisory software is used for production lines, site utilities and building services. Common protocols include Modbus, DNP3, IEC 60870-5-104, OPC UA and vendor-specific drivers.

Design considerations include polling rates and bandwidth, redundancy of servers and networks, alarm philosophy, historian retention and user access control. Because SCADA systems bridge operational and corporate networks, they are attractive targets for attackers, and IEC 62443 together with segmentation models such as the Purdue model guides their security. SCADA supervises rather than replaces controllers, and safety functions are handled by dedicated safety systems.

Key points

Supervises distributed processes; time-critical control stays in PLCs and RTUs
Core functions: data acquisition, HMI graphics, alarms, trends and event logs
Widely used in power, water, pipelines and multi-site manufacturing
Common protocols include Modbus, DNP3, IEC 60870-5-104 and OPC UA
Security guidance comes from IEC 62443 and network segmentation practice

Where AiVibe comes in

AiVibe designs and manufactures the AiAmbA AI Factory, whose edge devices and AI agents let people talk to PLC, CNC and robot controllers in plain language. Agents only propose changes, a trained operator confirms each one, and the AI Factory never replaces a machine's control or safety systems.

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Supervisory Control and Data Acquisition (SCADA)

Key points

Where AiVibe comes in

Related terms

Terms that refer to Supervisory Control and Data Acquisition (SCADA)