Bionic Mechanism Based Dynamic Trust Evaluation Method in Cloud Environment

摘要

In cloud environments, trust is one of the most important tools to enhance security. Trust can improve the reliability of cloud computing resources and has an important role in the business environments. In this paper, trust in cloud environment is regarded as a self-organizing system, using bionic mechanism, a dynamic trust evaluation method with family attribute is proposed. In this method, factors of trust evaluation include time, IP and behavior feedback. Data structure of access record table and trust record table are designed to store the relationship between ancestor nodes and descendant nodes. Based on trust information of the current node's ancestors, the biological evolution process is simulated. In order to minimize the influence of joint fraud on trust evaluation, the connected graph of ancestor nodes is constructed to evaluate the comprehensive trust of the node? which is converted to TSP problem and the optimal sequence of ancestor nodes is got by ant colony algorithm. The influence weight of ancestor node's trust on the current node's trust evaluation is denoted by the geometric sequence, and each factor's trust evaluation value of the current node is calculated. According to each factor's average weight of ancestor nodes, the comprehensive trust value of the current node is calculated. The simulation result shows that the trust evaluation method based on bionic mechanism is effective, and trust evaluation process of the current node can be regarded as comprehensive application of the ancestors' trust information, and the optimal trust sequence is searched. With increasing of ancestor nodes' trust information, the trust evaluation result is more accurate, which can effectively solve the joint fraud problem.