Identity-based Digital Signature Scheme

Information society is being pushed onto a new advanced level by computer network and communication technologies, which have made great effects on government, military affairs, culture education, and finance, etc. In a large number of network storage and transmission of data in need of protection, such as personal medical records, credit card account numbers, passwords landing network, or corporate strategy report, forecast sales, technical details Canbing, research, personnel files, and so on. These data may be stolen, exposed, tampering and forgery in the proess of storage and transmission. As the network environment and network information resources to deepen the growing dependence, Information has become an important resource in our society, information security is one of the rising subjects in information science and its core of technology is cryptology. In cryptological area, public-key cryptosystem because of its unmatched advantages compared with the traditional cryptoystem, especially in key management, is playing an increasingly important role. As a new branch of public-key cryptosystem, digital signature is a key technology of the secure B2B(Business to Business)and government affair in recent years.Digital signature, which can provide authentication, integrity and non-repudiation, is a key technique of information security. Compared with the Certificated Authority based (CA-based) cryptography, Identity-based (ID-based) signature can simplify the key management procedure from the view point of the efficiency and convenience. Identity based signature using pairing technology on elliptical curves has become one of the pop research problems. The main research of this thesis for identity-based signature in public-key cryptography includes identity-based proxy signature, blind signature, proxy blind signature and so on. The main contributions are as follows:1. Discuss two classic ID-based signature schemes in detail. And compare their computation efficiency. Present the security proof for ID-based signature. Point out Some open problems in ID-based signature.2. Discuss one ID-based signature scheme without trusted Private Key Generator (PKG) which was proposed resently, analysis it effective and security. The author introduces the concept of proxy signature and blind signature into Identity-Based encryption system. Then the author proposed two new efficient identity-based signature schemes: proxy signature and blind signature without a trusted party by using the bilinear pairing defined on Diffie-Hellman problems and Discrete Logarithm problem.. After detailedly discussing on its arithmetic security and efficiency, these new schemes were proved to be strong unforgettable and undeniable with comparison with other schemes.3. Analyzes a scheme proposed by Lee's "ID-Based Proxy Blind Signature Scheme" ,it pointed out the the existence of security flaws and improved. Furtuer, the author propose a new scheme which can satisfy all security for proxy blind signature's requirements,this paper proves that the safety scheme more efficient than the existing ones.