Research on Model of Trust Degrees for PKI

In order to improve the accuracy of trust evaluation of subscribers (or key holders) from relying parties’ point of view, a new model of trust degrees for PKI is proposed. By analyzing the security risks during the applying and using process of certificates and private keys, we introduce non-trust factor (NTF); then based on NTF, a method for trust degrees of keys is presented. Comparing with the existing work, the model integrates several critical factors which influence trust degrees of keys into one formula, thus improving the accuracy of trust evaluation for PKI and being applicable to a variety of PKI trust models.