Unique to each licensed hardware or software player.
AACS is a standard developed by a consortium (including Disney, Sony, and Microsoft) to prevent unauthorized copying of high-definition optical discs. The system works through a hierarchy of keys: aacs keys download
A file on the disc used to verify that the player hasn't been revoked. Unique to each licensed hardware or software player
The specific key needed to decrypt a single movie title. aacs keys download
The Definitive Guide to AACS Keys: Enabling Blu-ray Playback in Open-Source Players
Open-source players lack the official licenses to include these keys by default. Users must therefore provide a "key database" (typically a KEYDB.cfg file) to enable decryption. Blu-ray - ArchWiki