INFORMATION RECORDING DEVICE AND INFORMATION REPRODUCING DEVICE AND ACCOUNTING DEVICE AND JUDGING DEVICE AND UPDATING DEVICE AND INFORMATION UTILIZING DEVICE AND KEY DISTRIBUTING DEVICE AND RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide an information recording and reproducing device capable of constructing the utilization environment of digital information which assumes the protection of copyrights by acountings with respect to the utilization of the digital information easily. SOLUTION: An information recording device 1001 generates license information by ciphering contents information and by ciphering a utilizing condition to be referred in order to limit the utilization of the contents information and a decoding key decoding the ciphered contents information to record the ciphered contents information and the generated license information on a recording medium. An information reproducing device 1011 decodes the license information recorded on the recording medium by using a second decoding key for decoding the license information and judges whether the utilization of the contents information is possible or not based on the utilizing condition to be included in the decoded license information and when the utilization of the information is judged to be possible, the device 1011 decodes the ciphered contents information recorded on the recording medium by using a first decoding key to be included in the decoded license information.