类 BA N逻辑是一种用于分析密码协议安全性的逻辑 .在分析了 BA N,A T,M B,G NY,SV O等类 BAN逻辑之后 ,指出这些逻辑的缺陷 ,包括若干新发现的缺陷 .首先把类 BA N的模型抽象出来 ,形成一个五元组模型 ,然后分析该模型的各个要素 ,并依据该模型对类 BA N逻辑的缺陷进行分类 ,最后指出进一步发展类 BAN逻辑应解决的问题 The class BA N logic is a logic used to analyze the security of the cryptographic protocol. After analyzing BAN logic such as BA N, AT, MB, G NY, SV O, etc., these logical defects are identified, including several newly discovered defects First of all, the model of BA N is abstracted to form a five-tuple model, and then the various elements of the model are analyzed and the defects of the class BA N are classified according to the model. Finally, it is pointed out that the further development of class BAN logic should be solved problem