초록 ▼

In an electronic cash implementing method using a trustee, a user registers his identification information ID.sub.U and anonymous public key N with the trustee and receives a license (B,I). The user processes the license (B,I) by a public key corresponding to the amount to be issued and sends the pr

In an electronic cash implementing method using a trustee, a user registers his identification information ID.sub.U and anonymous public key N with the trustee and receives a license (B,I). The user processes the license (B,I) by a public key corresponding to the amount to be issued and sends the processed information to a bank to have it attach a blind signature to the information so that the user obtain electronic cash C from the blind signature. The user transmits to a shop the information B,I,C,N and a digital signature that assures the divisional use of the electronic cash. The shop verifies the validity of the information B and C and accepts it as cash and sends a history H of communication with the user to the bank and receives a payment therefrom. The bank places all received communication histories under its supervision and makes a check to see if the amount x spent by the electronic cash C is in excess of its face value X, and if so, informs the trustee of the information N contained in the communication history. The trustee uses the information ID.sub.U thus received to specify the corresponding user identification information ID.sub.U.

대표청구항 ▼

[ What is claimed is:] [1.] An electronic cash implementing method for an electronic cash system which contains a trustee and a bank, said method comprising steps:(1) wherein a user transmits his user identification information and an anonymous public key to said trustee;(2) wherein said trustee sto

[ What is claimed is:] [1.] An electronic cash implementing method for an electronic cash system which contains a trustee and a bank, said method comprising steps:(1) wherein a user transmits his user identification information and an anonymous public key to said trustee;(2) wherein said trustee stores the correspondence of said user identification information and said anonymous public key as a correspondence table in secrecy and generates and transmits a digital signature B of said trustee corresponding to said anonymous public key to said user;(3) wherein said user stores said digital signature B of said trustee as a license, shows said license and a face value X to said bank and requests said bank to issue electronic cash C of said face value X; and(4) wherein said bank issues to said user, by a blind signature, said electronic cash C associated with said license and corresponding to said face value X.