Patent attributes
Upon receiving an input of a request to move data to an external recording medium, a first information apparatus: transfers to record contents data after performing conversion under compression; encrypts the contents data and stores it in a concealment area of an internal recording medium; transfers to record the contents management information containing key information to the external recording medium; and deletes the encryption key. A second information apparatus: obtains the contents management information from the external recording medium and searches the network; obtains the encrypted contents data from the first information apparatus that holds the contents data concerned; and decrypts the encrypted contents data by using the encryption key contained in the contents management information.
