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Sean Parker Is Going To Great Lengths To Ensure 'Screening Room' Is Piracy Free, Patents Reveal (torrentfreak.com)
Napster co-founder Sean Parker has been working on his new service called Screening Room, which when becomes reality, could allow people to watch the latest Hollywood blockbusters in their living room as soon as they premiere at the box office. This week we get a glimpse at the kind of technologies Parker is using to ensure that the movies don't get distributed easily. From a report: Over the past several weeks, Screening Room Media, Inc. has submitted no less than eight patent applications related to its plans, all with some sort of anti-piracy angle. For example, a patent titled "Presenting Sonic Signals to Prevent Digital Content Misuse" describes a technology where acoustic signals are regularly sent to mobile devices, to confirm that the user is near the set-top box and is authorized to play the content. Similarly, the "Monitoring Nearby Mobile Computing Devices to Prevent Digital Content Misuse" patent, describes a system that detects the number of mobile devices near the client-side device, to make sure that too many people aren't tuning in. The general technology outlined in the patents also includes forensic watermarking and a "P2P polluter." The watermarking technology can be used to detect when pirated content spreads outside of the protected network onto the public Internet. "At this point, the member's movie accessing system will be shut off and quarantined. If the abuse or illicit activity is confirmed, the member and the household will be banned from the content distribution network," the patent reads. [...] Screening Room's system also comes with a wide range of other anti-piracy scans built in. Among other things, it regularly scans the Wi-Fi network to see which devices are connected, and Bluetooth is used to check what other devices are near.
Are you fuckin kidding me you start a p2p music app more less based on pirated material and now you swung the complete opposite way on this project.
There's no nice way to put this but "Fuck you Sean".
Heavy duty traitor tracing systems are far more sophisticated than that. Watermarks are low frequency and spread spectrum (both resolution and temporal). Meaning each receiver gets their own, dedicated encoded stream. The tracing system will simply identify *all* the accounts used to combine the signal. In layman terms, its like mixing signals of different frequency - you can separate those out again if you know what to look for, though in practice fancy number/coding theory methods are used for reasons below.
If you attempt to extract common component, from a small number of signals, you *still* can identify the sources from the supposedly "common" signal you get, because what you get actually isn't a baseline, you'll still include all the unique marks of all the accounts they had in common. This is possible because despite the low bandwidth, the steganographic bandwidth as a whole is fairly high (millions of bits per minute), and you need to interpose just few to get a match.
Let me repeat some grade school set theory:
The true signal is made of 2 4 6 components. Signal A is 1 2 3 4 6 and signal B is 2 3 4 5 6. The common "pirate" set you get by "substracting" is 2 3 4 6. The problem is, 3 now identifies you as a set union. This scheme is run on *hundreds of millions of bits*, and can easily identify unique copies and arbitrary combinations of copies to very high degree. Not only the result remains watermarked, but you can determine the precise set intersections.