What term describes a disk drive where the controller automatically encrypts data written to it?

What term describes a disk drive where the controller automatically encrypts data written to it?

• A. Trend analysis
• B. Configuration baselines
• C. Self-encrypting drives (SED)
• D. Opal

Answer: (C)

Self-encrypting drives describe disks that automatically encrypt data with the drive's own controller as it is written, and decrypt it when read, making data at rest unreadable if the drive is accessed without proper unlock. This on-the-fly, hardware-based encryption is the defining feature of such drives, so the term precisely describes what’s happening: encryption happens automatically by the controller without requiring software to handle it. That’s why this option is the best fit. It captures the automatic, hardware-managed protection that sits inside the disk itself, not relying on external software. Opal, while related, is a standard that defines how such encryption and key management should be implemented and accessed; it’s a specification, not the general term for the drive type. The remaining choices refer to unrelated concepts like trend analysis or configuration baselines, which have nothing to do with encryption of data at rest.

Self-encrypting drives describe disks that automatically encrypt data with the drive's own controller as it is written, and decrypt it when read, making data at rest unreadable if the drive is accessed without proper unlock. This on-the-fly, hardware-based encryption is the defining feature of such drives, so the term precisely describes what’s happening: encryption happens automatically by the controller without requiring software to handle it.

That’s why this option is the best fit. It captures the automatic, hardware-managed protection that sits inside the disk itself, not relying on external software. Opal, while related, is a standard that defines how such encryption and key management should be implemented and accessed; it’s a specification, not the general term for the drive type. The remaining choices refer to unrelated concepts like trend analysis or configuration baselines, which have nothing to do with encryption of data at rest.