Although they have actually existed for many years, P2P technologies promise to radically change the future of networking. P2P file sharing software has also created much controversy over legality and "fair use." In general, experts disagree on various details of P2P and precisely how it will evolve in the future.
Traditional Peer to Peer NetworksThe P2P acronym technically stands for peer to peer. Webopedia defines P2P as
"A type of network in which each workstation has equivalent capabilities and responsibilities. This differs from client/server architectures, in which some computers are dedicated to serving the others."
Home Peer to Peer NetworksMost home computer networks today are peer to peer networks. Residential users configure their computers in peer workgroups to allow sharing of files, printers and other resources equally among all of the devices. Although one computer may act as a file server or Fax server at any given time, other home computers often have equivalent capability to handle those responsibilities.
Both wired and wireless home networks qualify as peer to peer environments. Some may argue that the installation of a network router or similar centerpiece device means that network is no longer peer to peer. From the networking point of view, this is inaccurate. A router simply joins the home network to the Internet; it does not by itself change how resources within the network are shared.
P2P File Sharing NetworksWhen most people hear the term "P2P", they think not of traditional peer networks, but rather peer to peer file sharing over the Internet. P2P file sharing systems have become the single most popular class of Internet applications in this decade.
A P2P network implements search and data transfer protocols above the Internet Protocol (IP). To access a P2P network, users simply download and install a suitable P2P client application.
Numerous P2P networks and P2P software applications exist. Some P2P applications work only with one P2P network, while others operate cross-network. Likewise, some P2P networks support only one application, while others support multiple applications.