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..
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.