RTU or PLC? — TechKnowSurge

About this interactive

A remote terminal unit (RTU) and a programmable logic controller (PLC) both control equipment, and today they overlap a great deal. Historically, PLCs were the more advanced, and RTUs the more basic. The key to where an RTU fits is distance. It controls equipment that is remote, out in the field: oil pumps, pipelines, water stations. A central server is not always reachable from there, so the RTU is programmed to control the equipment on its own, and it reports back when it can. A PLC fits on the factory floor, close to the SCADA system that directs it. To sort a card, ask where the equipment is: out in the field, far from central control, or inside the plant.

What you'll learn

Decide whether a remote terminal unit (equipment out in the field, far from central control, able to run on its own) or a programmable logic controller (equipment on the factory floor) fits a control job better

Aligned to

CompTIA Security+

3.1 Compare and contrast security implications of different architecture models.

Key terms

Remote Terminal Unit: A field device, often at an unstaffed site far from any building, such as a pipeline station or substation, that collects sensor readings and carries out commands for a SCADA system over a long-distance link and can keep running its equipment on its own; compromising one can give an attacker control of physical infrastructure.
Programmable Logic Controller: A rugged industrial computer that runs stored instructions to automate machinery and processes on a plant floor, reading its sensors and switching equipment in response; exploiting one can cause physical damage.
Supervisory Control and Data Acquisition: An architecture in which a central server and its software gather readings from sensors and field units across a plant, pipeline or region and send commands back to them, used in critical infrastructure, where a security failure can damage physical equipment.

Topics

Interactive Streak Sort

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