A recording apparatus generates key information based at least on contents reproduction permission information, encrypts contents based on the key information, and records the encrypted contents and recording date/time information on a recording medium. A reproducing apparatus reads the encrypted contents and the recording date/time information from the recording medium, acquires reproduction date/time information on the encrypted contents and, based on the recording date/time information that was read, the reproduction date/time information, and reproduction permission limit information on the encrypted contents, generates contents reproduction permission information indicating that the encrypted contents maybe reproduced. The reproducing apparatus generates key information based at least on the contents reproduction permission information and decrypts the encrypted contents that were read.

 
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