FIELD: information technologies.
SUBSTANCE: invention relates to method of control of access to data (CT) coded by means of control words (CW) received by protection module in control messages (ECM) and returned to module of coded data processing. Control messages (ECM) contain at least the first control word (CW1) and the second control word (CW2), at the same time each of specified control words provides access to coded data (CT) during the specified period of time called cryptoperiod (CP). Method includes the following actions: transfer of coded data into at least one module of processing; and transfer of control messages (ECM) into specified processing module, besides, control messages (ECM) contain at least two specified control words (CW1, CW2) and are sent to processing module after transfer of data coded by means of the first control word (CW1) and prior to transfer of data coded by means of the second control word (CW2), time shift between transfer into module of processing of data coded by means of the first control word (CW1) and transfer of control message (ECM), containing the first control word (CW1) and the second control word (CW2), makes more than 75% of cryptoperiod.
EFFECT: prevents access to coded content with fraudulent use of two decoders with only one module of protection.
4 cl, 4 dwg
