Advanced Access Content System

The Advanced Access Content System, or AACS, is the system that protects the new generation of high-definition DVDs from unauthorized copying. The specifications of this technology, and the associated licenses, are publicly available from the AACS’s web site. I have prepared a tutorial on AACS based on these specifications. This tutorial is useful for AACS licensees or potential licensees, especially engineers who are designing DVD players.

The tutorial is available for free; just send a message requesting it to

The tutorial explains some of the trickier aspects of AACS:

This page last modified 11/17/2006.