| 摘要 |
PURPOSE:To protect an information, and at the same time, to easily perform the copy of a medium as in the past by writing in the information in an information recording area after encoding it into a cipher by the code of a cipher key register, and making the information difficult to understand, at the time of the recording of the information. CONSTITUTION:When a data is written in the recording medium, the code for encoding it into the cipher is set in the cipher key register 4. An encoding means 5 encodes the written data into the cipher by using the contents of the register 4 by the control of a controlling means 7, and a recording means 2 writes in the encoded data in the medium 1. When the data is read out, the code for decoding is set in the cipher key register 4. The controlling means 7 requests the information from an objective sector, and a reproducing means 3 reads out the encoded data from the medium 1 and sends it to a decoding means 6. The decoding means 6 decodes the read out data by the contents of the register 4, and restores and transmits the data. |
