METHOD FOR PERFORMING VERIFICATION PROCESS ONLY USING PUBLIC KEY WITHOUT USING SECRET INFORMATION OF USER IN DIFFERENT APPROVAL DOMAIN

摘要

PURPOSE: A public key verification method is provided to reduce communication volume and calculation volume by enabling an approval with a public key itself and to verify the public key in a different approval domain while secret data on a user is not being exposed. CONSTITUTION: The method comprises several steps. A user terminal generates a public key by using a secret key parameter of the user terminal itself and a public key parameter of a key issuing organization(201, 203). Identification data on the user terminal and the generated public key are transmitted to the key issuing organization(205). The key issuing organization inputs identification data and a public key parameter of the organization itself into a one directional hash function, and generates approval data of the key issuing organization itself(209). The identification data from the user terminal and the public key are inputted into the hash function(211). An approval public key is generated by using the approval data of the key issuing organization, the approval data of the user terminal, and the public key parameter(213). The generated approval public key is transmitted to the user terminal.