Peer-to-Peer Information ManagementPeer-to-Peer (P2P) systems rely on ad-hoc communications between machines in order to offer services to a community. Contrary to the classical client-server architecture, P2P systems consider all peers, i.e. all nodes participating in the network, as being equal. Hence, peers can simultaneously act as clients consuming resources from the system, and as servers providing resources to the community. Figure 3.1 shows a client-server and a P2P system side by side.