Design And Analysis Of Anonymous Proxy Signature Scheme

This paper studies anonymous proxy signature from two aspects: One is the security analysis of the present schemes. The other is the design of the new schemes. The main contributions of this paper are as follows.Firstly, we give the security analysis of the interrelated basic proxy signature scheme, LKK scheme and the main improved schemes of it. We analyze the security of three improved LKK schemes down to date. We point out the schemes, proposed by Yangweiqiang et al and proposed by Huangwenping, still have weakness and present the attack methods to them. And we point out the scheme, proposed by Yangshudi et al, can keep the property of the strong unforgeability and does not need the secure channel.Secondly, we do research on the anonymous proxy signature schemes with a trusted party. We point out that the attack to Shum-Wei scheme presented by Sun et al is invalid. Then we propose a valid attack. And we improve Lee et al's attack. We also point out that the Shum-Wei scheme has the redundant data.Then we design a new scheme which can keep the property of the strong unforgeability and has a more compact signature.Thirdly, we do research on the anonymous proxy signature schemes without a trusted party. We point out the schemes, proposed by Wangchanglin and proposed by Gulize et al, have weakness and present the attack methods to them. We also point out that the scheme, proposed by Gulize et al, has the redundant data.Then we design a new scheme which can keep the property of the strong unforgeability and does not have the redundant data.Fourthly, we propose the anonymous proxy multi-signature. In this new type of schemes one proxy signer can generate an anonymous proxy signature on behalf of two or more original signers. Then we design an anonymous proxy multi-signature scheme with a trusted party and two schemes without a trusted party.In the end, we propose the forward secure anonymous proxy signature which combin the concept of forward security. In this new type of schemes it can realize the forward security and keep the property of the anonymity at the same time. Then we design a forward secure anonymous proxy signature scheme with a trusted party and another scheme without a trusted party.