Digital Signature Based On Elliptic Curve Cryptography And Its Application In Intrusion Tolerance CA

Nowadays, networks technique is applied more and more, people pay moreattention to the security of the information in networks. Digital signature technologycurrently is a hot research area of network security. Since elliptical curve is proposedby N. Koblitz and Miller that it could be applied in encryption algorithm, Ellipticcurve cryptography is the most secure public key cryptography, which is based on theintractability of the elliptic curve discrete logarithm problem. And it has become amajor subject of the cryptography at home and broad. Therefore, it has importantsignificances in the research in ECDSA and its application to threshold signature.This paper mainly researches elliptical curve cryptography. A threshold signaturesystem based on elliptical curve has been put forward. Then the following works havebeen completed:(1) First, the basic theory of elliptical curve cryptography is introduced.Especially elliptic curve digital signature algorithm ECDSA is introduced andimproved. So a digital signature algorithm P_ECDSA is presented, which eliminatesthe inverse calculation of the limited domain in the ECDSA algorithm and improvingthe efficiency of the algorithm. The most important thing is that P_ECDSA can beapplied to the secret sharing.(2) On the basis of the existing secret sharing schemes, a secret sharing schemewithout a share distributed center is improved. Mainly a scheme of updating thesecret key by period is proposed, which makes the secret sharing scheme has theforward security. An example of the secret sharing scheme without a share distributedcenter using the small number is given which verifies the correctness of the secretsharing scheme.(3) A kind of security strengthened (t, n) threshold signature scheme TP_ECDSAbased on elliptical curve cryptography is proposed, which is based on the algorithmP_ECDSA and the improved secret sharing scheme. Then scheme TP_ECDSA'ssecurity is analyzed to verify its security performance is reliable. (4) Threshold signature scheme TP_ECDSA is applied to intrusion tolerant CA.Mainly, a scheme of CA signs certificates is presented. This scheme reduces thecalculation overhead by transferring the same job that t signers are needed to finish toCA. BY comparing with the CA scheme of ITTC project from the availability, safetyand efficiency. This scheme's superiority is proved.(5) Meanwhile this paper designed a digital signature system based on theP_ECDSA algorithms and analyzed of its system architecture. Then we realize thedigital signature system by programming. The realization result indicates that thedigital signature algorithm P_ECDSA is effective.