Peer-to-Peer Systems

Peer-to-peer technologies (or P2P for short) have broken through in recent years as an attractive alternative to the traditional client-server-based architectures and systems. A lot of the attention paid to peer-to-peer systems has been caused by the widespread use of P2P file sharing networks, where (often illegal) media content is being distributed. Recently deployed peer-to-peer systems however demonstrate that the peer-to-peer concept extends to other applications as well and can also be used in commercial scenarios. In this chapter, we will present a definition of what peer-to-peer is and what it means as a communication paradigm. In many ways, peer-topeer is the opposite of the traditional client-server communication paradigm, since in peer-to-peer networks all nodes are more or less equal in terms of their duties and privileges. We will give abstract