Through the analysis of two proxy blind signature schemes, we want to prove that this two proxy blind signature schemes can not resist forgery attack and both have linkability.
对两个代理盲签方案及其安全性进行分析，证明了这两个方案不具有不可伪造性和不可链接性。
2
In this paper, we put forward a practical anonymous authentication scheme with identity escrow and controllable linkability which allows a user to control the linkability among his authentications.