The Research And Realization Of A Authentication Based On Proactive-ELGamal Sharing Threshold Secret System

With the development of computer network and cryptology , sharing threshold secret comes into more important area. This system is different from the traditional. It distributes the responsibility of key managering and monitoring.the concepts , development and appliances of sharing threshold secret and comper with the verifiable secret sharing scheme,secret sharing without the trust and proactive secret sharing is discussed in the dissertation. Then a authentication based on proactive-ElGamal sharing threshold secret system is proposed. The system has the following feature:1. The system has not the trusted authority which can prevent the authority cheat.2. The new system is based on proactive secret sharing which has more secrety because the agrressor must get more than t secret ciphertexts in a period not t secret ciphertexts in the total time in order to get the system secret.3. Zero authentication is introduced in the process of authentication ,which makes authentication easier.4. We only compute d~-1 (d is the private key of client )not random number x's x~-1 in the authentication process which based on ELGamal.After describing our system , we analyize the process of key arithmetics,for example,ELGmal, Lagrange and the transmission of the secrte information.Then we intoduce the detail of this system through modeling CA(Certification authority) and clients.At the end of paper ,we expect the development of appliantion of threshold secret sharing.