PEER TO PEER NETWORK

摘要

Peer-to-peer networks employing simple peers and super peers strike a balance between centralized (client-server based) and entirely flat peer-to-peer approaches. They introduce hierarchy into peer-to-peer networks in the form of super peer nodes, peers which have extra capabilities and duties in the network. There are problems in the identification and election of peers to take the role of super peer: in particular, the need for regular update messages to communicate peer availability across the network significantly impacts discovery times (when a simple peer attempts to advertise a service or requests a service from another peer). A presence server is implemented in the network in order to monitor the availability of each peer. A device called the "super peer elector" subscribes to receive updated availability information from the presence server and assigns super peer status to the most appropriate, and available, simple peer.