Independent Verification Of Proxy Multi-signature

As the advancement of information technology, people much more dependent on computernetwork in their work and life at present. Consequently, some problems about information securityinevitably emerge when people use the network. The security problems include identification problem,data integrity and nonrepudiation. According to a common view, the information security problemsabove can be solved by exiting technologies such as cryptography and digital signature.In previous proxy signature schemes, a proxy signature is created on behalf of only one originalsigner. The schemes are referred to proxy mono-signature schemes. Now, a new proxy signaturescheme called the proxy multi-signature scheme is presented. In the scheme, a proxy signer cangenerate a proxy signature on behalf of two or more original signers. And original signers need tosend their signature power to others to make a proxy signature. However, the schemes cannot wellsatisfy the requirement of privacy protection for that the verifier needs to collect all the public keys oforiginal signers and proxy signer to verify the signature. Obviously, the verification phase of proxymulti-signature proboblely leaks the delegationships of the original signers and the proxy signer. Insome application areas, it’s only needed to verify the agent has the authorization from some originalsigners rather than all the original signers. This kind of issue is called the independent verificationproblem of proxy multi-signature. However, there is no related work to answer the above questions.In this paper, the independent verification framework of proxy multi-signature is proposed. Thecontributions of the study are as follows:1. Standardized description and formalize definition of independent verification framework.Independent verification of proxy multi-signature is a special case of traditional proxymulti-signature schemes. A standardized description and a formalize definition of independentverification property are proposed in this paper, which makes the researches more systematic andformalized.2. Attack model of independent verification proxy multi-signature. Existing attack modelsbased on proxy multi-signature involve three participants who are the original signers, the proxysigner and the verifier. As the previous attack models cannot well satisfy the requirements ofindependent verification, a general attack model of proxy multi-signature has been improved inthe study. What is more, the attack model based on independent verification is added.3. Three independent validation schemes of proxy multi-signature. Three different principlesare proposed based on independent verification proxy multi-signature schemes attached with the corresponding security analyses. The first scheme is put forward based on the fundamentaltheorem of arithmetic. The scheme, which has high flexibility of verification, must has thepowerful computing capabilities. The second scheme is based on Shamir’s secret sharing schemeand general proxy multi-signature scheme. Compared with the first scheme, the second schemeis suitable for the scenes of low computing power, but it has no requirement on verification’sflexibility. The third scheme is a secure independent verification proxy multi-signature scheme instandard model. The scheme can be used to the scences of high computing power and highsecurity requirements. The security analyses of the schemes prove that the proposed schemes arefeasible.4. Some extension forms of the proposed independent verification scheme. The independentverification scheme proposed in the study can be extended to different forms according todifferent application requirements. The properties of anonymity and accountability can be addedinto the scheme. Furthermore, a VIP pertinent independent verification scheme is proposed, inwhich one needs one or more VIP pertinents’ public keys or shares to make the signatureeffectively, or no one can verify the signature successfully.