AACSprotected

AACSprotected refers to content that is safeguarded by the Advanced Access Content System (AACS), a copy protection and digital rights management (DRM) standard used primarily on Blu-ray Discs and some related media. The label indicates that the media or file is encrypted and access requires authorized hardware or software with valid AACS credentials.

AACS was developed by a consortium led by AACS Licensing Administrator (AACS LA) and launched in the mid-2000s to replace earlier protection schemes. The system relies on a hierarchy of cryptographic keys and blocks: a Media Key Block (MKB) on the disc, title-specific keys (Title Keys) used to decrypt individual layers or titles, and the actual content encryption. A licensed player or device, containing a device key and processing logic, uses these elements to decrypt and render the content. In practice, the content remains unreadable on unlicensed hardware.

In addition to encryption, AACS employs key revocation mechanisms. If a device or key is compromised, the revocation list can render certain devices unable to decrypt new content, prompting updates to MKBs and related components. Some discs also utilize supplementary protections (such as BD+), but AACS remains the core framework for protecting Blu-ray content.

Legal and policy considerations accompany AACS protection. Circumventing AACS to copy, distribute, or access protected content is restricted by law in many jurisdictions and may violate licensing terms. The presence of the AACSprotected label signals that appropriate authorization and compliant playback equipment are required. See also: Blu-ray, DRM, AACS.