TorrentFreak has discovered a patent filed by AT&T that details a technology to accurately measure the flow of both infringing and legitimate file-sharing traffic on P2P networks like BitTorrent. Thus, this system enables AT&T to detect pirated downloads and combat congestion on its network. Whether the company is actually using this technology or not is unknown at this point.

Titled "Method and apparatus for automated end to end content tracking in peer to peer environments", AT&T's patent was filed in December 2009, published on June 4, 2013, and awarded to AT&T's Intellectual Property division. It focuses primarily on torrents which are gathered by crawling search engines and additional torrent-focused websites through RSS feeds.

"Content distribution using peer-to-peer protocols (P2P) accounts for a large percentage of traffic generated on the Internet," AT&T states. "The content may be legitimately or illegitimately distributed via P2P. For example, some content may be legitimately purchased and downloaded by users via P2P. However, some content may be pirated and illegally copied and distributed P2P violating copyright laws and reducing revenue for the content producers and distributors."

Hide your traffic from your ISP with the best torrenting VPN

According to the patent, the system scans each content title that is uploaded and downloaded via torrent on the network. Titles that are downloaded over a predetermined threshold will be added to a list, ordered from most popular to least popular, in the company's database. It then downloads the actual torrent to verify that the content listed inside (content signature) verifies with the content title stored in the database.

The system can also identify each unique user that has downloaded the content title in the list. It then pretends to be a torrent client and contacts the user's own client to request a download. A successful connection means that the unique user has actually downloaded the content title. Busted.

Based on the system's description, AT&T believes this patent is the answer to the current problem of accurately monitoring content shared on P2P networks.

"[Currently] if an individual wants to track a particular content title that is distributed via P2P, the individual must track content on a single content title basis," AT&T states. "In other words, the individual must know ahead of time which content title they want to monitor and perform the monitoring manually for each content title. This becomes a very time consuming and laborious process."

The full patent can be read here.