关键词: 可信计算, 信任评估, 模糊理论, 信任链, 度量

Abstract: Trust chain is one of the key technologies in trusted computing, and how to express it and assess it is a current hot research focus. According to the complex factors which influence the trust assessment and the uncertainty and dynamism of trust relation in trust computing environment, a trust computing assessment method was proposed based on fuzzy theory. This method established level five space for the trust particle, the historical measurement record and time attenuation factor were introduced to construct the direct trust, and a fuzzy evaluation method of indirect trust was also given. By defining similar degree function with the improved Einstein operator, the trust entity fuzzy reasoning and evaluation process of trust chain was given. This method combined fuzzy reasoning with trust transferring, and it could assess the trust of entity in trust chain fully. The simulation experiments show that, the proposed method has a better ability to resist the malicious assessment and has better credibility and reliability in the results of the assessment as compared with other similar methods. It is a new method for the trust assessment in trusted computing.

Key words: trusted computing, trust assessment, fuzzy theory, trust chain, measurement