PLAYBACK DEVICE AND PLAYBACK METHOD Russian patent published in 2005 - IPC

FIELD: data carriers.

SUBSTANCE: device for reproduction of data from data carrier, program zone of which is used for recording a set of files, and control zone - for controlling copy protection data concerning the file, recorded in program zone, has computer for calculating copy protection information for each time file is reproduced, comparison means for comparing value, calculated on reproduction command, being prior to current one, to value, calculated on current reproduction command, and if these values coincide, the last value is stored as copy protection value, calculated on reproduction command , prior to current one and control means for allowing reproduction of file, appropriate for current command, if value, calculated as response to command, previous relatively to current command, coincides as a result of comparison to value, calculated as a response to current command.

EFFECT: higher reliability, higher efficiency.

4 cl, 46 dwg