Patent ID: 7164767

Claim:
In a data transfer system comprising a data transfer device and a data recording device, said data transfer system characterized in that: said data transfer device includes: primary recording medium drive means for performing recording and/or reproduction of data to a primary recording medium; storage control means for controlling content data so as to be stored in said primary recording medium in an encrypted compressed data state; transmission means for sending data to said data recording device; and transmission control means for, in a case of sending the content data stored in said primary recording medium to said data recording device through said transmission means, comparing a data compression system and a bit rate that are conformable to said data recording device with a data compression system and a bit rate of content data to be sent, and then allowing said content data to be sent as it is in the encrypted compressed data state in a case of a first comparison result, while allowing said content data to be sent as a state of encrypted non-compressed data in a case of a second comparison result, and said data recording device includes: reception means for receiving data sent from said data transfer device; secondary recording medium drive means for recording data in a secondary recording medium; decrypting means for converting the encrypted content data having been transferred from said data transfer device into a non-encrypted state; and recording control means for allowing said secondary recording medium drive means to record the compressed data already converted into the non-encrypted state by said decrypting means in said secondary recording medium after performing a required addition processing on said compressed data in a case of the content data having been sent in accordance with said first comparison result, while allowing said secondary recording medium drive means to record non-compressed data already converted into the non-encrypted state by said decrypting means in said secondary recording medium after performing a compression processing on said non-compressed data in a case of the content data having been sent in accordance with said second comparison result.