关键词: 前向安全, 指定验证者, 门限代理, 匿名性

Abstract: Through the analysis of a forward secure threshold proxy signature scheme with designated verifier, it shows that even valid proxy signature could not be verified, because the scheme’s signature verification equation is wrong, and the scheme does not have the feature of anonymity. In order to deal with these disadvantages, an improved forward secure threshold proxy signature scheme is proposed. By updating the partial keys to achieve success in updating the collection members’ signing secret key, which makes it nearly impossible that no single member is expected to control the updating of the signing secret key. The new scheme has the feature of verifiability as well as anonymity.

Key words: forward secure, designated verifier, threshold proxy, anonymity