摘要:
A security unit to prevent unauthorized retrieval of data includes an encrypting unit for encrypting data in accordance with commands received by the security unit, and a common register for storing both intermediate results and final results of the data encryption. A switching element operatively coupled to the register selectively outputs the contents of the register. The switching element is controlled to prevent external access to the intermediate results of the encryption. The security unit is particularly useful as part of a memory unit that is attachable to a recording/reproduction device such as a digital audio recorder/player.
摘要:
A security unit to prevent unauthorized retrieval of data includes an encrypting unit for encrypting data in accordance with commands received by the security unit, and a common register for storing both intermediate results and final results of the data encryption. A switching element operatively coupled to the register selectively outputs the contents of the register. The switching element is controlled to prevent external access to the intermediate results of the encryption. The security unit is particularly useful as part of a memory unit that is attachable to a recording/reproduction device such as a digital audio recorder/player.
摘要:
A security unit to prevent unauthorized retrieval of data includes an encrypting unit for encrypting data in accordance with commands received by the security unit, and a common register for storing both intermediate results and final results of the data encryption. A switching element operatively coupled to the register selectively outputs the contents of the register. The switching element is controlled to prevent external access to the intermediate results of the encryption. The security unit is particularly useful as part of a memory unit that is attachable to a recording/reproduction device such as a digital audio recorder/player.
摘要:
The present invention provides a data processing method and apparatus capable of shortening the processing time required when editing previously encrypted track data. An example of a transfer of audio track data between a portable player and a storage device is provided. The track data is comprised of one or more parts, each of which in turn is comprised of a series of data blocks. Each block of the track data is encrypted prior to transfer using a block key. The block keys are determined in such a manner that subsequent editing of the track data which results in redistribution of the parts does not require full decryption of the data.
摘要:
A memory unit such as a memory card is removably attachable to a data processing unit such as a digital video recorder or an audio recording/reproducing unit. The memory unit includes a non-volatile memory, a security unit for protecting the security of data stored in the non-volatile memory, and an interface that receives control data from the data processing unit. The control data is either first control data for a read or write operation with respect to the non-volatile memory, or second control data (different from the first control data) for a security operation of the security unit. Thus, a security-type memory card is compatible with both a security type and a non-security type data processing unit.
摘要:
A recording apparatus is disclosed, that comprises a compression process means for compressing an input digital signal corresponding to a predetermined compression process and segmenting the compressed digital signal into blocks, a fixed value generating means for generating a predetermined fixed value, an adding means for adding the fixed value generated by the fixed value generating means at a predetermined timing to the blocks of the digital signal compressed by the compression process means, an encrypting means for encrypting the fixed value and the compressed digital signal added by the adding means, and a recording means for recording the fixed value and the compressed digital signal encrypted by the encrypting means to a record medium.
摘要:
A reproducing apparatus for reproducing data from a record medium having a program area and a management area, the program area being used for recording a plurality of files, the management area being used for managing forging prohibition information against a particular file recorded in the program area is disclosed, the apparatus comprising a calculating means for calculating the forging prohibition information managed in the management area of the record medium whenever a file recorded in the recorde medium is reproduced, a comparing means for comparing a value calculated by the calculating means corresponding to a former reproduction command with a value calculated by the calculating means corresponding to a current reproduction command, and a controlling means for permitting the file corresponding to the current reproduction command to be reproduced when the value calculated corresponding to the former reproduction command is the same as the value calculated corresponding to the current reproduction command as the result of the comparing means.
摘要:
A recording apparatus is disclosed, that comprises a compression process means for compressing an input digital signal corresponding to a predetermined compression process and segmenting the compressed digital signal into blocks, a fixed value generating means for generating a predetermined fixed value, an adding means for adding the fixed value generated by the fixed value generating means at a predetermined timing to the blocks of the digital signal compressed by the compression process means, an encrypting means for encrypting the fixed value and the compressed digital signal added by the adding means, and a recording means for recording the fixed value and the compressed digital signal encrypted by the encrypting means to a record medium.
摘要:
A recording apparatus is disclosed, that comprises a compression process means for compressing an input digital signal corresponding to a predetermined compression process and segmenting the compressed digital signal into blocks, a fixed value generating means for generating a predetermined fixed value, an adding means for adding the fixed value generated by the fixed value generating means at a predetermined timing to the blocks of the digital signal compressed by the compression process means, an encrypting means for encrypting the fixed value and the compressed digital signal added by the adding means, and a recording means for recording the fixed value and the compressed digital signal encrypted by the encrypting means to a record medium.
摘要:
A reproducing apparatus has three reproducing modes that are a first mode, a second mode, and a third mode. In the first mode, when a program that has been reproduction restricted is tried to be reproduced, the reproducing operation is paused and the user is asked whether he or she wants to reproduce the program. Corresponding to the user's reply, the reproducing operation is performed or prohibited. In the second mode, a program that has been reproduction restricted is prohibited from being reproduced. In the third mode, a program that has been reproduction restricted is unconditionally reproduced. When the power of the apparatus is turned on at step S31, a prompt that causes the user to select one of the first mode, the second mode, and the third mode is displayed. At step S33, a process for designating a mode is performed. Information of the designated mode is stored in a nonvolatile memory.