Abstract:
A peer-to-peer (P2P) system is known by its scalability and dynamic nature where nodes can join and leave the system easily and anytime. These networks are susceptible to malicious behaviors such as nodes dropping messages and misleading requesting nodes. P2P routing protocols are not immune against these misbehaviors. Therefore, detecting and dealing with malicious nodes will certainly lead to more reliable and secure system. In this paper, we propose a trust aware system for P2P routing protocols. The proposed system analyzes constantly the behaviors of all nodes to determine their trust-worthiness then classify them accordingly isolating the ones deemed malicious. It tracks the nodes' reputation based on evaluation reports from the nodes themselves. The credibility of nodes that are inaccurately evaluating other nodes is also monitored, thus, malicious evaluations would not affect other nodes' reputation. We have integrated the proposed approach with several P2P routing protocols and evaluated their performance through simulations measuring parameters such as request delivery ratio, malicious detection, and false negatives. Results show that the proposed approach improves significantly the performance of P2P routing protocols. © 2014 IEEE.