Dynamic trust mechanism based on multi-constraints and collaborative filtering in mobile Ad hoc networks
移动自组网中基于多约束和协同过滤动态信任机制

Due to their distributed nature, mobile ad hoc networks (MANETs) are vulnerable to various attacks. To enhance security of MANETs, it is necessary to build a trust model for executions in a self-organizing and non-certified center network environment. This paper proposes a dynamic trust mechanism (DTM) based on multi-constraints and collaborative filtering in MANETs. The main idea of our method is to introduce a trust updating algorithm with multi-constraints (time aging factor ensures that the trust fades with time; rewards factor ensures that good peers deserve to be rewarded; and penalty factor ensures that the selfish or the malicious deserve to be punished) to assess direct trust by self-experience of nodes, and to adopt collaborative filtering technique to evaluate recommendation trust in order to prevent false recommendations. The analytic results show that DTM not only can compute trust between nodes more precisely than Bayesian model, but also can improve security of MANETs through quantitative evaluation analysis and extensive simulations.