responsible for all data recovery and backups, while in P2P systems, each node requires its own backup system. Because of the lack of central authority in P2P networks, forces such as the recording industry, RIAA, MPAA, and the government are unable to delete or stop the sharing of content on P2P systems. Applications Content delivery In P2P networks, clients both provide and use resources. This means that unlike client–server systems, the content-serving capacity of peer-to-peer networks can actually increase as more users begin to access the content (especially with protocols such as Bittorrent that require users to share, refer a performance measurement study). This property is one of the major advantages of using P2P networks because it makes the setup and running costs very small for the original content distributor. File-sharing networks Many peer-to-peer file sharing networks, such as Gnutella, G2, and the eDonkey network popularized peer-to-peer technologies. Peer-to-peer content delivery networks. Peer-to-peer content services, e.g. caches for improved performance such as Correli Caches Software publication and distribution (Linux distribution, several games); via file sharing networks. Copyright infringements Peer-to-peer networking involves data transfer from one user to another without using an intermediate server. Companies developing P2P applications have been involved in numerous legal cases, primarily in the United States, over conflicts with copyright law. Two major cases are Grokster vs RIAA and MGM Studios, Inc. v. Grokster, Ltd.. In the last case, the Court unanimously held that defendant peer-to-peer file sharing companies Grokster and Streamcast could be sued for inducing copyright infringement. Multimedia The P2PTV and PDTP protocols. Some proprietary multimedia applications use a peer-to-peer network along with streaming servers to stream audio and video to their clients. Peercasting for multicasting streams. Pennsylvania State University, MIT and Simon Fraser University are carrying on a project called LionShare designed for facilitating file sharing among educational institutions globally. Osiris is a program that allows its users to create anonymous and autonomous web portals distributed via P2P network. Other P2P applications Bitcoin and additional such as Ether, Nxt and Peercoin are peer-to-peer-based digital cryptocurrencies. Dat, a distributed version-controlled publishing platform. Filecoin is an open source, public, cryptocurrency and digital payment system intended to be a blockchain-based cooperative digital storage and data retrieval method. I2P, an overlay network used to browse the Internet anonymously. Unlike the related I2P, the Tor network is not itself peer-to-peer; however, it can enable peer-to-peer applications to be built