| 摘要 |
In one aspect of the invention is a method for preventing unauthorized copies of a medium, such as a DVD, from being played by a compliant device by using the validation area (VA) region of a medium to validate keying material. A compliant device is a device that will validate keying material. In one embodiment of the invention, a compliant device validates keying material by using the value in the VA region of the medium. In alternative embodiments, a compliant device will validate keying material by checking correspondence between keying material written to a non-VA region of a medium and validation data written to a VA region of a medium. In the alternative embodiments, if the keying material does not correspond to the validation data, then a compliant device will prevent the contents of the medium from being played. |
