Research On Proxy Signature Schemes And Their Applications

In daily life, people often transfer their right of signature to some reliable agents, and the agents can exercise the right in term of the formers. In electronic information society, peoples also frequently meet the problem of entrusting the right of signature. So proxy signature, as a very important branch of digital signature, comes into being. In today's rapid development of electronic information society, proxy signature has been widely used in mobile communication, mobile agents, e-commerce and so on. At the same time, the applications put forward higher request on the safety of proxy signature.In this thesis, proxy signature schemes are analyzed and studied deeply. First of all, the development history of proxy signature is introduced. Secondly, three proxy signature schemes which are more secure and effective than previous ones are proposed by using bilinear pairings on elliptic curve and other relevant tools. (1) Because current proxy signature schemes cannot prevent proxy key exposure attack, we put forward a method that can protect proxy signature scheme from proxy key exposed attack. (2)We formally clearify the difference and relationship between proxy re-signature and proxy signature and give two transformation methods transferring from re-signature to proxy signature. (3)Based on a certificateless signature scheme, we proposed a certificateless proxy signature scheme. And above schemes are analyed and testified safe.At last, we report the applications of above proxy signature schemes.