The Buddy System - A Distributed Reputation System Based On Social Structure
Stefan Fähnrich, Philipp Obreiter, Birgitta König‐Ries · 2004
In P2P networks, there are no incentives to cooperate. There is neither a reward for cooperation nor a punishment for non-cooperation. A distributed reputation system could solve this problem, by giving means of managing trust towards other entities and discovering vicious entities. The existing distributed reputation systems are based on plausibility considerations and, thus, have several limitations. Therefore, in this report, we aim at overcoming these limitations by proposing the Buddy System as a distributed reputation system that is based on social structure. For this purpose, we discuss the design space of social structures and choose an appropriate social structure for the Buddy System. We consider implementation issues for its social structure by taking into account the volatility of the P2P network. Finally, we show by the means of simulation that the Buddy System significantly improves the e#ectiveness and e#ciency of conventional distributed reputation systems. More specifically, the Buddy System is more e#ective in the detection of vicious entities and does not introduce any additional communication overhead. Contents 1