What does data encryption at rest protect?

• A. Stored data
• B. Data in transit
• C. Data in memory only
• D. Data being processed

Answer: (A)

Data encryption at rest protects stored data. It keeps information unreadable on disks, databases, backups, and other storage media when it’s not being used, so if a device is lost or accessed without authorization, the data remains protected. It doesn’t cover data in transit (which is protected by encryption while it moves between systems) or data in memory and during processing (which are handled by other protections and require decryption to use). Remember that effective at-rest protection relies on strong key management; without secure keys, the protection isn’t as strong.