QUALITY BASED SERVICE SELECTION IN A PEER TO PEER NETWORK

摘要

A peer-to-peer network operating in accordance with a service-oriented architecture is disclosed. The peers in the network request services from one another and each keep a record of the quality of service they receive from the other peers. The peers can operate in two modes of service provider selection. In a first mode, the selection is so as to favour service providers which have provided the peer with good service in the past. In a second mode, the selection is probabilistic and can therefore select service providers other than those that have provided good service in the past. Each device keeps track of the relative success of adopting the second mode of selection. By occasionally using the second mode of selection and adopting the second mode of selection more frequently should the relative success of adopting the second mode of selection rise, a more rapid adjustment by the network to changing network conditions is enabled. This leads to a better utilisation of the resources of the computers of the network than has hitherto been achieved. The invention finds particular application in distributed applications which dynamically select a Web Service to perform a function at run-time.