INFORMATION PROCESSING APPARATUS AND METHOD, PROGRAM, AND RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide an information processing apparatus that prevents unauthorized use of data. SOLUTION: A key storage part 51 of data stores decoding keys by the number of contracted users that are encrypted by a public key of the contracted users. When the user uses data of a non-public part 62, the user uses the private key to decrypt the encrypted decryption key in the key storage part 51 corresponding to the user and uses the decrypted decryption key to decrypt the encrypted data of the non-public part 62. Personal information is written in a label and the label is imbedded to the decrypted data as a watermark. The label imbedded in the data as the watermark is used to locate the source of the data when the data are illegally used.