Objective Focusing on the s ecurity problem of authentication and confidentiality in the context of computer networks, a digital signature scheme was proposed based on the public key crypt osystem. Methods Firstly...Objective Focusing on the s ecurity problem of authentication and confidentiality in the context of computer networks, a digital signature scheme was proposed based on the public key crypt osystem. Methods Firstly, the course of digital signature based on the public key cryptosystem was given. Then, RSA and ELGamal schemes were de scribed respectively. They were the basis of the proposed scheme. Generalized EL Gamal type signature schemes were listed. After comparing with each other, one s cheme, whose Signature equation was (m+r)x=j+s modΦ(p) , was adopted in the des igning. Results Based on two well-known cryptographic assumpti ons, the factorization and the discrete logarithms, a digital signature scheme w as presented. It must be required that s' was not equal to p'q' in the signing p rocedure, because attackers could forge the signatures with high probabilities i f the discrete logarithms modulo a large prime were solvable. The variable publi c key “e” is used instead of the invariable parameter “3” in Harn's signatu re scheme to enhance the security. One generalized ELGamal type scheme made the proposed scheme escape one multiplicative inverse operation in the signing proce dure and one modular exponentiation in the verification procedure. Concl usion The presented scheme obtains the security that Harn's scheme was originally claimed. It is secure if the factorization and the discrete logarithm s are simultaneously unsolvable.展开更多
文摘Objective Focusing on the s ecurity problem of authentication and confidentiality in the context of computer networks, a digital signature scheme was proposed based on the public key crypt osystem. Methods Firstly, the course of digital signature based on the public key cryptosystem was given. Then, RSA and ELGamal schemes were de scribed respectively. They were the basis of the proposed scheme. Generalized EL Gamal type signature schemes were listed. After comparing with each other, one s cheme, whose Signature equation was (m+r)x=j+s modΦ(p) , was adopted in the des igning. Results Based on two well-known cryptographic assumpti ons, the factorization and the discrete logarithms, a digital signature scheme w as presented. It must be required that s' was not equal to p'q' in the signing p rocedure, because attackers could forge the signatures with high probabilities i f the discrete logarithms modulo a large prime were solvable. The variable publi c key “e” is used instead of the invariable parameter “3” in Harn's signatu re scheme to enhance the security. One generalized ELGamal type scheme made the proposed scheme escape one multiplicative inverse operation in the signing proce dure and one modular exponentiation in the verification procedure. Concl usion The presented scheme obtains the security that Harn's scheme was originally claimed. It is secure if the factorization and the discrete logarithm s are simultaneously unsolvable.
