Abstract: A contents database in which data of contents enciphered by a C key is stored and provided for a contents server, wherein the contents data enciphered by the C key are enciphered by an M key and sent to a user machine. In the user machine, the contents data enciphered by the C key are stored in a storage device. Upon reproduction, the contents data enciphered by the C key from the storage device are sent to an enciphering/decoding processing unit and decoded and charging is performed in accordance with the C key. A dynamic authenticating code which dynamically changes with the elapse of time is added to the C key.

Abstract: A recording and reproducing apparatus has a communicating unit, a reading unit, a storing unit, a control unit, and an output unit. The communicating unit transmits and receives data to/from an information center in which a plurality of additional information have been stored. The reading unit reads out recorded data from a recording medium on which a plurality of data and index data of a plurality of data have been recorded. The data read out from the recording medium by the reading unit is stored in the storing unit. The control unit reads out the additional information corresponding to the recording medium from which the data is read out by the reading unit from the information center by the communicating unit and writes the read-out additional information into the storing unit as additional data of the recording medium which is read out by the reading unit. The output unit outputs the data stored in the storing unit and the additional data.

Abstract: A recording and reproducing apparatus has a communicating unit, a reading unit, a storing unit, a control unit, and an output unit. The communicating unit transmits and receives data to/from an information center in which a plurality of additional information has been stored. The reading unit reads out recorded data from a recording medium on which a plurality of data and index data relating to the plurality of data have been recorded. The data read out from the recording medium by the reading unit is stored in the storing unit. The control unit reads out the additional information corresponding to the recording medium from which the data is read out by the reading unit from the information center by the communicating unit and writes the read-out additional information into the storing unit as additional data of the recording medium which is read out by the reading unit. The output unit outputs the data stored in the storing unit and the additional data.

Abstract: A recording and reproducing apparatus has a communicating unit, a reading unit, a storing unit, a control unit, and an output unit. The communicating unit transmits and receives data to/from an information center in which a plurality of additional information have been stored. The reading unit reads out recorded data from a recording medium on which a plurality of data and index data of a plurality of data have been recorded. The data read out from the recording medium by the reading unit is stored in the storing unit. The control unit reads out the additional information corresponding to the recording medium from which the data is read out by the reading unit from the information center by the communicating unit and writes the read-out additional information into the storing unit as additional data of the recording medium which is read out by the reading unit. The output unit outputs the data stored in the storing unit and the additional data.

Abstract: An information center, a terminal apparatus, a dubbing system and a dubbing method. Utilize a plurality of terminal apparatuses each owned by a user and an information center common to the terminal apparatuses. Data such as musical software can be dubbed from a recording medium such as a compact disc mounted on the terminal apparatus to other media such as a hard-disc driver employed in the terminal apparatus provided that a dubbing permission is granted by the information center. That is to say, prior to dubbing, the terminal apparatus establishes communication with the information center in order to obtain such a permission and other information related to the recording medium typically as a fee-charging service. The main function of the information center, therefore, is authentication of the user making a request for a permission to dub data. A request for such a permission made by the user may be rejected depending on the result of authentication.

Abstract: A recording/reproducing apparatus is free from a jitter problem caused by a rotational drive of a recording medium such as a magneto-optical disk.

Abstract: A recording/reproducing apparatus is free from a jitter problem caused by a rotational drive of a recording medium such as a magneto-optical disk.

Abstract: A signal reproducing apparatus for reading out signals recorded along with clock signals on a recording medium. The relative velocity between a magnetic tape and magnetic heads mounted on a rotary drum is sensed by a rotary drum rotational velocity sensor and the center oscillation frequency of a VCO in a clock-reproducing PLL circuit of signal reproducing circuitry is changed in accordance with the sensed relative velocity for controlling the center oscillation frequency to be equal to the frequency of the clock components of the reproduced RF signals. The clock signal components may be reproduced as usual even though the frequencies of the clock components of the playback RF signals are changed. Moreover, fluctuations in the relative velocity between the magnetic tape and the magnetic head may be tolerated to diminish the load on the velocity servo control operation as well as to reduce power consumption and expedite the operation.

Abstract: A recording and reproducing apparatus has a communicating unit, a reading unit, a storing unit, a control unit, and an output unit. The communicating unit transmits and receives data to/from an information center in which a plurality of additional information have been stored. The reading unit reads out recorded data from a recording medium on which a plurality of data and index data of a plurality of data have been recorded. The data read out from the recording medium by the reading unit is stored in the storing unit. The control unit reads out the additional information corresponding to the recording medium from which the data is read out by the reading unit from the information center by the communicating unit and writes the read-out additional information into the storing unit as additional data of the recording medium which is read out by the reading unit. The output unit outputs the data stored in the storing unit and the additional data.

Abstract: A recording and reproducing apparatus has a communicating unit, a reading unit, a storing unit, a control unit, and an output unit. The communicating unit transmits and receives data to/from an information center in which a plurality of additional information have been stored. The reading unit reads out recorded data from a recording medium on which a plurality of data and index data of a plurality of data have been recorded. The data read out from the recording medium by the reading unit is stored in the storing unit. The control unit reads out the additional information corresponding to the recording medium from which the data is read out by the reading unit from the information center by the communicating unit and writes the read-out additional information into the storing unit as additional data of the recording medium which is read out by the reading unit. The output unit outputs the data stored in the storing unit and the additional data.