Trust Model of Users' behavior in Trustworthy Internet

As traditional network security cannot meet the security requirements, the international research shows that network security is on the way to Trustworthy Internet and that the trustworthy issue becomes a hot topic in the future Internet. Trust evaluation of users' behavior is an important part of Trustworthy Internet and a rational trust model plays a key role in the evaluation. This paper concludes many principles of the trust model by analyzing existing trust models and proposes a novel trust model including both the direct and indirect trust. In our model, the direct trust is more trustworthy and is weighted more with the more and more interactions and the indirect evaluation becomes less and less important. The subjective factor is considered to make the direct trust obey the principle of "rise-lowly, decline-quickly". Furthermore, recommenders' credibility is taken into account in the indirect trust evaluation, which can avoid the denigration and make indirect trust more objective. We also consider the process of referral of the credibility to gain more information to evaluate the indirect trust effectively. Credibility evaluation is the basis of the filtering of low credibility and the improvement of trust evaluation. Finally, several experiments are shown to illustrate the properties of the model.