Reputation-Based Algorithm for Managing Trust in File Sharing Networks

Peer-to-peer file sharing networks, such as Gnutella, have gained large success and reached millions of users. However, the decentralized and anonymous characteristics of these networks open the door to abuses by malicious peers spreading tampered resources such as viruses and worms. Moreover, file sharing networks are vulnerable to problems and security concerns such as the selfishness of users which brings on the free-riding problem, the zero-cost identity problem, and the collusion among nodes to incorrectly promote or malign other nodes. To address these problems, we propose a robust reputation framework that integrates aspects of multiple trust domains and trust dimensions, a fairness participation scheme and an access control mechanism. We show that our system is highly effective in preventing the spread of malicious content and in promoting fairness under various threat models