中文摘要：

给出了一种离线TTP公平非否认协议的分析方法,离线TTP公平非否认协议得到了广泛的研究,针对离线TTP公平非否认协议的分析并不是那么广泛.针对离线TTP公平非否认协议具有协议簇的特点,将协议实例化,实例化后可以对单个协议实例的非否认性和有效性进行分析;通过扩展Kailar逻辑,增加时间相关限定词来表述协议的执行序列,用协议执行序列来表达和分析协议的公平性和时效性.利用该方法,对两种公平非否认协议进行分析,分析的结果表明CCD不符合公平性,而ZG的时效性不能够得到满足.

英文摘要：

Off-line TTP fair non-repudiation protocols have been studied widely.Compared with on-line TTP fair non-repudiation protocol,off-line TTP fair non-repudiation protocols are analyzed rarely.Off-line TTP fair non-repudiation protocols are often composed by several subprotocols,which are defined as protocol cluster.In this paper,a kind of analysis method of off-line TTP fair non-repudiation protocol is proposed.There are three main points in this paper.Firstly,according to the cluster properties of off-line TTP fair non-repudiation protocol,protocols are instanced.Through instancing,non-repudiation and effectiveness of off-line TTP fair non-repudiation protocol can be analyzed within each single instance.Secondly,as asynchronous communication,sending and receiving actions can not exactly reflect true events of protocol.Through refining the actions of participants,protocols can be represented as the participants＇ action sequence.And the participants＇ action sequence can be used to analyze the violation of execution.Thirdly,the time determiner is introduced to express and verify the timeliness property of the protocol.Finally,two off-line TTP fair non-repudiation protocols are analyzed,among which ZG off-line TTP protocol is composed by two subprotocols and CCD off-line TTP protocol is composed by three subprotocols.The results of analysis indicate that ZG off-line TTP protocol is verified,which does not meet timeliness,and CCD off-line TTP protocol is verified which does not meet fairness.