Quantitative trust assessment method based on Bayesian network

With the continuous development of cloud computing, Internet of Things (IoT) gradually involves in all walks of life, which contains large amounts of sensitive information, privacy information. In addition, the most direct and serious security risks are malicious nodes involving in information acquisition and data fusion, which send false information and eavesdrop instructions sent with legal identity. Therefore, it is greatly urgent to ensure the security of IoT, especially trust relationship among nodes. In order to determine whether to allow the new node to join the network and to remove the existing malicious nodes, this paper proposes a quantitative trust assessment method based on Bayesian network. Through classification of nodes' trust state, integration of trust priori probability and allocation of conditional probability, the trust probability of assessment nodes could be predicted and inference to determine the trust level. Finally, the simulation results show the effectiveness of assessment method and that the assessment subjectivity can be reduced to some extent.