Research Of Multi-signature Algorithm

From the late nineties of the last century, as the process of society information technology and network communication technologies continuously improve, the rapid development of information has become a modern society and an important resource factor, alongside human society and material, talent and energy. However, the threats in the process of informatization are multi-faceted, such as hackers attack on computer systems, and intelligence agents'attacks on the network, including eavesdropping, interception, tampering, forgery and other attacks. The information transmitting in the network needs an effective security tool. Therefore, the information security technology has emerged, including two branches, the public-key cryptosystem and digital signature system. Digital signature for the secure transmission of information network provides an effective protection. Digital signature has a very wide scope of application, including e-commerce, e-government, and digital rights management system.In this paper, researching the basis of the digital signature, focusing on the specific application needs, the multi-signature algorithms are studied. Multi-signature is mainly used on the occasion while a joint document signed, such as the management with different pairs of signing permission of a company, when signing the same document required from low to high, level by level for approval, then they use multi-signature by the order of grade transmission, in order to protect the legal validity of signed documents.In this paper, we research the multiple digital signature algorithms, and mainly research three multi-signature schemes based on different difficult problems, and achieved the following results:1)Through the study of elliptic curve cryptosystem, we found that many multi-signature schemes based on system, existed joint attack by some of the interior signer. This paper presents a multi-signature scheme based on that can resist such joint attack. This scheme took advantage of follow-up signer's and signature verifier's verification, in order to resist the joint attack. At the same time, the program removed the inverse problem of multiplication of many multi-signature algorithms commonly used in order to improve the execution speed of the algorithm. In this article, a number of multi-signature schemes based ECCECC on is analyzed and compared to prove that the program has certain advantages also from the security and speed of execution. ECC2)Through the study of vector space secret sharing, we found that many multi-signature schemes based on vector space secret sharing existed public key substitution attack. It pointed that one of the multi-signature schemes which be confronted with such public key substitution attack. Propose a possible attack plan, and prove the feasibility of the plan. Propose a new program that can overcome the public key substitution attack, and give the security analysis and proof of the program. The new program made use of the rational use of the parameters of hash function and its anti-collision characteristics, in order to overcome the external public key substitution attack.3)In-depth study of the knowledge of bilinear mapping , found that some of the signature scheme based on bilinear mapping also exists security flaws such as the public key substitution attack, cited the existence of such an attack in which a bilinear multi-signature scheme, and developed a possible attack plan. The analysis revealed that as long as the full use of the strong collision characteristics of hash function, and put the public key parameters of the signer into the hash calculation, we can solve this security risk. This paper presents a multi-signature scheme based on bilinear pair that can resist the public key substitution attack, and gives security analysis and certification.