Research On Proxy Signature Scheme

With the development of the network of computers,information security becomes a crucial factor affecting the developing of network. Digital Signature is one important problem of cryptography,playing a very important role in the present information society.It is the simulation of cultural script signature,being able to validating the electronic information.Digital Signature can meet the demand of E-commerce and E-government affairs by offering the integrity and discrimination of the data.It is the basis and guarantee of the theory of information security.In reality,people often think it is a must to entrust some of their rights,including the right of signature,to some reliable agents,then, the agents can exercise the rights by standing for them.In information society,people often meet the problem of entrusting the right of signature,so,how to entrust the rights of Digital Signature effectively and securely becomes a very important problem to be solved.Proxy signature,as a very important branch of digital signature,comes into being.According to this question,Mambo,etc.put forward the concept of a kind of particular proxy signature and drew the original scheme in 1996, that is Digital Signature,which blazed a new way for the development of digital signature.Proxy signature is defined that the primitive signer who has the right of signature empowers the proxy signer under the premise of not letting out his own private keys;then,the proxy signer can have a valid proxy signature by representing the primitive signer and the receiver of the proxy signature can test and verify if it is valid or not.As a new breed of digital signature technology,Proxy Signature has drawn people' s attention by its high quality.Many scholars have carried out deep explorations and researches and scored great successes in this field.With many basic proxy signature schemes raised,a slew of new proxy signature are springing up such as proxy multi-signature,threshold proxy signatures,ID-based proxy signature,blind proxy signature,proxy signatures with warrant recovery,one-time proxy signatures,ect.Proxy signature will have a bright future with wider use in electronic banks, E- commerce and mobile agent.This paper mainly focuses its research on the following respects:(1) This paper briefly reviews the research background and present situation of proxy signature and makes clear the significance of the proxy signature scheme.After expounding in detail the basic concepts and theories of digital signature and proxy signature,the author introduces some typical proxy signature schemes,analyzes their security and then point out their defects respectively.(2) This paper studies a Elliptic Curve Proxy Signature Scheme,which applied proxy signature based on DLP to the elliptic curve key system, so a typical Proxy Signature Scheme Based on Elliptic Curve Crypto-systems is put forward.The new scheme has the basic characteristics of delegate proxy.Besides,it features much higher security,less amount of counting,faster speed of disposal,much less key-length,much less demand of bandwidth,ect.(3) It is becoming the research center to combine Proxy Signature with other special Digital Signature,and set up a set of practical Proxy Signature Scheme of higher efficiency and security.Based on the study of Blind Signature and Proxy Blind Signature,this paper analyzes and discusses a kind of Proxy Blind Signature Scheme, points out the existing security problems of it as well as makes proposals for improvement.