分析了一种基于Guillou-Quisquater数字签名方案的代理签名方案存在的一些安全隐患,指出它是弱代理签名,并在此方案的基础上进行改进得到更加安全有效的强代理签名方案.
Some unsecurities of an existed proxy signature scheme based on Guillou-Quisquater digital signature are analyzed. It is found to be a weak proxy signature. After modifying it more secure and valid, strong proxy signature is obtained.