Opal defines standards for creating and managing interoperable self-encrypting drives. The 81-page specification is full of new storage device logical specs, protocols, and data structures. The Opal standard was even reviewed and approved by the NSA. Key management is not defined, but left to the implementer to determine. It’s good that the standard doesn’t lock a manufacturer or software management vendor into a particular key management scheme. But key management isn’t required or even discussed. The standard is more about how and where particular values must be placed on the drive.”]
Source: https://www.csoonline.com/article/2633233/tcg-sets-the-drive-encryption-standard.html