【摘要】 各种广义ＥｌＧａｍａｌ签名本质上是可以相互转换的，从而都易受到代换攻击，文中利用它们相互转换的条件来刻画它们之间的一种安全性关系，并从总体上给出了它们的安全性分类．最后指出了在Ｓｃｈｎｏｒｒ模式下所有的广义ＥｌＧａｍａｌ签名是强等价的．更多还原

【Abstract】 All ElGamal type schemes may be transformed into each other essentially, which is vunlnerable under substitution attack. This paper describes a security relation among them according to the transforming conditions, and draws a classification of their security. Finally, it is pointed out that all ElGamal type schemes are strong equivalent in Schnorrmode.更多还原