What are OT and ICS?
Operational technology (OT) covers the equipment that commands and monitors physical processes: programmable controllers, operator interfaces, sensors, gateways. Industrial control systems (ICS) are the part that runs production, energy, water or buildings.
Why it matters for your organization
This equipment was designed for closed networks. Remote maintenance and the convergence of IT and plants open access paths nobody decided on: a maintenance access left open, a controller plugged straight into the Internet, a forgotten gateway.
The protocols involved
Each family of equipment speaks its own protocol: Siemens S7, Modbus TCP, EtherNet/IP, DNP3, OPC UA, IEC 60870-5-104, among others. The IEC 62443 standard frames the security of these systems, from the asset owner down to the components.
To know what can be reached from the Internet in your plants, and how to check it without touching production, see the Factory security page.