ATTRIBUTE AUTHENTICATION METHOD, KEY MANAGEMENT APPARATUS, SERVICE PROVISION DESTINATION APPARATUS, SERVICE PROVISION SOURCE APPARATUS, AND ATTRIBUTE AUTHENTICATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a technology of preventing a service provision destination apparatus from consuming a huge amount of memory capacities for storing a plurality of attribute certificates.;SOLUTION: An attribute certificate issue apparatus 10 encrypts attribute information by using a different encryption key by each of attribute information items. A key management apparatus 20 groups decryption keys corresponding to the encryption keys and cross-references a different random number by each of the groups and the decryption keys belonging to the group corresponding to the random number and stores the random numbers and the decryption keys in cross reference with each other. A user terminal 30 transmits an encrypted random number generated by encrypting a random number by using a public key of a server 40 and an attribute certificate to the server 40. The server 40 decrypts the random number from the encrypted random number by using a private key of its own apparatus. The key management apparatus 20 transmits a stored decryption key in cross reference with the random number decrypted by the server 40 to the server 40. The server 40 acquires attribute information corresponding to the decryption key by decrypting the attribute certificate received from the user terminal 30 through the use of the decryption key received from the key management apparatus 20.;COPYRIGHT: (C)2008,JPO&INPIT