Re: And now for something completely different !
"Set up a passcode system where viewing the watermarked file requires entry of a unique code known only to the preview holder. Log the viewer's passcode entry event on a remote, well secured database (not Sony's)."
Impossible. The disc has to be viewable at some point, and there's where ANY multimedia copy protection falls flat: pirates simply find a way to record the video during actual playback. No amount of DRM will be able to totally beat it because, at some point, it must be human-viewable for it to be useable; the pirates simply record past that point in the chain. Plus, like you said, some devices may be completely offline with way to get online, meaning there's no real chain of trust possible since an offline check against a read-only disc can be circumvented by a replay attack.
Biting the hand that feeds IT
