DEVICE AND METHOD FOR REPRODUCING DIGITAL CONTENT

摘要

PROBLEM TO BE SOLVED: To delete a content key from a digital content reproducing device at the point of time when right is consumed, while preventing the loss of the right by a power interruption, concerning a times designation license with a threshold till the determination of one-time usage set therein.

SOLUTION: A digital content reproducing device includes: a decrypting part 101; a key storage part 103; and a key available time measuring part 104. A threshold time is previously set in the key available time measuring part 104. The decrypting part 101 reports the key available time measuring part 104 that a content is decrypted. The key available time measuring part 104 performs the subtraction of the key available time held in the part 104 and reports the time to a control part 105 after an available time elapses. The control part 105 deletes the content key stored in the key storage part 103, based on the report. When usage is performed over the threshold time, time obtained by subtracting the threshold time from the time length of the content is added to and set in the key available time measuring part 104.

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