This article is missing information about Opalite and Pyrite, two subsets defined by the TCG (& the even simpler TCG Enterprise). Please expand the article to include this information. Further details may exist on the talk page. (June 2023)
The Opal Storage Specification is a set of specifications for features of data storage devices (such as hard disk drives and solid state drives) that enhance their security. For example, it defines a way of encrypting the stored data so that an unauthorized person who gains possession of the device cannot see the data. That is, it is a specification for self-encrypting drives (SED).
The Opal SSC (Security Subsystem Class) is an implementation profile for Storage Devices built to:
Protect the confidentiality of stored user data against unauthorized access once it leaves the owner's control (involving a power cycle and subsequent deauthentication).
Enable interoperability between multiple SD vendors.[1]
Radboud University researchers indicated in November 2018 that some hardware-encrypted SSDs, including some Opal implementations, had security vulnerabilities.[2]