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The RIAA has a team of individuals working hard to crack down on illegal downloading. This group investigates peer-to-peer (P2P) networks and is seen as vital to the successful future of the recording industry. Despite its efforts, the demand for pirated content online is still high and it is hard to see how much illegal downloading their actions have deterred. To root out illegal downloading activity, the RIAA works with MediaSentry, which has developed customized programs that operate over the Gnutella Network, the same as many popular P2P networks. The company has a list of song titles owned by RIAA-member company and gives specific hash codes to each song file. If more than one user on a network has the same song file with the same hash code, they know it is being shared illegally. The company can also download songs that they do not already have to see if they are RIAA-owned by "fingerprinting" the recordings.
While a copyright owner cannot sue every person who downloads their song illegally, they can notify the infringer's Internet service and block their material. If the RIAA identifies a user with a popular hash code of just one digital file, it is enough to send a take down notice to the ISP. Many universities claim that they are being targeted illegally, but the RIAA says that is not true and not technically possible. They find what they find through public means.
The RIAA uses litigation against only the most egregious of users. When that happens, they file the suit and target the IP address's registered user. OF the tens of thousands of suits filed against commercial ISP's, universities, and individual file sharers, only one has reached trial.