Many people associate peer-to-peer technology with file-sharing applications such as BitTorrent, Gnutella, Kazaa, and Napster and with concerns about the unauthorized, free distribution of video, audio, and other copyrighted content. These concerns have led the entertainment industry to crack down on P2P systems. For example, the US Recording Industry Association of America (RIAA) has taken numerous file sharers to court to recover copyright-infringement damages. P2P was adopted first by folks looking to share unauthorized content and is still widely used for that purpose. In addition, ISPs have complained that high volumes of large video files and other P2P traffic traveling between multiple peers have hurt their networks' performance. This has also inhibited P2P usage in some cases and cast doubts upon its future growth potential. In response, proponents have undertaken a major effort to change P2P technology, rehabilitate the approach's reputation, and encourage its use for fast, efficient content distribution and improved Internet-based communications services, including telephony.