The patent in question is named “Real-time content detection in ISP transmissions” and focuses exclusively on tracking and deterring online piracy. According to the telco, copyright infringement is a “recurring problem in Internet usage” that is hard to police without the proper tools..

via PRISM for Pirates: AT&T Invents The Ultimate Anti-Piracy System | TorrentFreak.

It looks like deep packet inspection comparing against hashes of known violating content that constantly updates.  Even the patent seems obvious as I had that idea circling in my head how they would do that as soon as I read the headline of this article.   This is not innovative.  AT&T must feel comfortable with their monopoly status to screw over customers like this.  I can’t imagine keeping hash tables of content violations accurate will be very easy.   Add to that the security implications of hackers infecting these tables with bogus hashes and you have a recipe for disaster.  Only a company with monopoly status can take such a risk because many of their “customers” have no other choice for Internet access.