Lights, camera, controls! [DVD copying prevention]

The possibility of one DVD spawning countless perfect digital copies is, for the movie industry, the scenario for the ultimate horror show. Following the breaking of the content scramble encryption system for DVDs by a 16-year-old Norwegian programmer, Jon Johanssen, and the following lawsuit (decided in favour of the movie industry), several approaches for preventing the copying of DVDs are being considered. Some of these mechanisms block copies from being made in the first place, others stop the playback of copies after the fact. The techniques are outlined in this article.