It is common in electricity, water, oil and gas, transport, and other environments where remote sites communicate with one or more control centers.
A SCADA system usually provides operators with process visibility, alarms, historical data, and supervisory commands. Local controllers continue much of the real-time control, while central systems coordinate and monitor the wider operation. The exact architecture varies, and a SCADA system does not need to be connected to the public internet.
Key points
Typical componentsSCADA servers, HMIs, remote terminal units, PLCs, field devices, historians, communications links, and engineering stations.
Security prioritiesTrustworthy measurements and commands, controlled remote access, resilient communications, safe local operation, and recovery of configurations.
Architecture realityGeographic distribution and low-bandwidth or legacy links can affect monitoring, authentication, and update options.
Important limitationProtecting only the central server leaves field equipment, communications, engineering access, and operational procedures exposed.