IEC
IEC 62443
Security for Industrial Automation and Control Systems
A series rather than a single document, giving the risk assessment method, the zone and conduit model, security levels and the requirements placed separately on the asset owner, the integrator and the product supplier. For an integrity engineer its value is that it treats the control system as a plant asset with a defined architecture rather than as IT, so the realistic controls it points to are segmentation, removable media control, managed vendor remote access and recoverable backups rather than patching equipment that cannot be rebooted.
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