Self-Certified Short Designated Verifier Signature And Its Applications

In daily life, there is extensive research and development on digital signature, which has become important foundation of information security systems. With the rapid development of network and information technology, electronic commerce and government affairs have become more and more related to everyone, such as electronic bank, electronic shopping and electronic voting. In 1996, Jakobsson, Sako and Impagliazzo proposed the concept of designated verifier signature, in which only the designated verifier can verify the validity of signature. Because of such special property, designated verifier signature has gained intensive attention and deep research. Desginated verifier signature schemes with different feature have sprung up and applied into different scenes in electronic commerce and government affairs.For a secure designated verifier signature scheme, if we could shorten its length, it would be significant. In 2006, Huang, Susilo, Mu and Zhang proposed two short strong designated verifier signature schemes, which are by now the most efficient on signature's generation and length. For instance, in their schemes, complicated computing can been finished offline and the length of signature is 160 bits when the range of the selected hash function is 160 bits. Hence, short designated verifier signature is particulally usefull in circumstance where bandwidth is limited.Self-certified cryptosystem is firstly propsed by Girault in 1992. As an intermediate type between certificate cryptosystem and id-based cryptosystem, it doesn't need explicit authentication to public key by certificate and have the key escrow problem. Self-certified cryptosystem has lots of advantages: less storage spaces, computing and communication; more secure since user can select his private key by himself.Therefore, in this thesis, by the first time we combine short designated verifier signature and self-certified cryptosystem and propse the first short designated verifier signature scheme based on self-certified cryptosystem, which not only has the advantage of Huang et al.'s schemes, but also takes in the feature of self-certified cryptosystem.With the popularization of wireless network and mobile communication technology, there will be greater significance in theory and application for electronic commerce and government affairs and especially for the establishment of mobile network to study self-certified short designated verifier signature.Finally, we give some open questions and prospect the further research focus of our scheme.