How do OT and IT security differ?

Fundamentals

IT typically emphasizes confidentiality and integrity; OT gives higher priority to human safety, process stability, and equipment availability.

Industrial systems can operate for decades and may only be updated during planned shutdowns, making segmentation, passive monitoring, and access control especially important.

Complete separation of OT and IT is no longer a realistic assumption. Secure architecture must identify, restrict, and monitor essential paths.

The distinction is not only technical; decision ownership also differs. OT security changes must be coordinated with operations, process engineering, and safety, with a rollback path defined before implementation.

An effective program starts with assets and critical flows, then prioritizes least access, event logging, recoverable backups, and joint IT/OT response according to consequence.