Personal information protection system, its signature key update method and personal information collection method, the key management device and the key generation program, signing key generation device and the signature key generation program, personal information management apparatus and personal information collection program, as well as, content decoding apparatus and personal information management program

摘要

PROBLEM TO BE SOLVED: To provide personal information protection technology for minimizing leak damages of personal information.;SOLUTION: This personal information protection system 1 has a key management server 3 and a personal information management server 4 connected to each other via an internal network N2. The key management server 3 has: a key generation means for generating a master key and a verification key; a partial key generation means for generating a partial key used in the case of updating a signature key at predetermined timing based on the master key and the verification key, and key update frequencies of the signature key; and a communication line control means for communicably connecting/separating the internal network N2. The personal information management server 4 has a partial key acquisition means for acquiring the partial key generated by the key management server 3, and a signature key update means for updating the signature key stored in a signature key storage means based on the partial key, adds a signature to a request for collecting personal information such as content viewing and listening history by the signature key to transmit the request to a receiving terminal 5, and accumulates and manages the collected information.;COPYRIGHT: (C)2007,JPO&INPIT