Research On Identity-Based Signature Scheme

In nowadays, 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. 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 is playing more and more important roles in the world because of its native predominance. 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.As one of the pivotal technologies of information security, digital signature provides authentication, integrality and incontestableness. In traditional public key infrastructure (PKI) system, managing public-key certification causes problems of complexity and high cost. Fortunately, identity-based cryptography has solved these kinds of problems, and it is also a good replenisher to PKI system. 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 group signature, proxy signature and hierarchical signature. The conclusion is as follows:1. This thesis analyses and sums up schemes of existing identity-based signature and identity-based special signature, discusses the security and efficiency of some typical ones, and finally points out the existing issues and developing trends of present identity-based digital signature.2. A new identity-based proxy signature scheme is advanced. After detailedly discussing on its arithmetic security and efficiency, this new scheme is proved to be strong unforgettable and undeniable with comparison with other schemes.3. A new scheme of identity-based hierarchical signature is constructed basing on the scheme of Boneh's identity-based hierarchical encryption. This new scheme has been proved to be secure in resisting fabrication at the situation of adaptively chosen message attacks, by using sample identity model in standard model. It is also compared with the present schemes at aspects of efficiency and memory cost.