FIELD: copy protection of data; mass production in standard hardware and reading standard readers. SUBSTANCE: during CD ROM manufacture key data are entered by varying data for reading or error correction code data, key data are extracted by means of driver program in compliance with driver program concerning location of changed data in recorded data, and key data are used to ensure reading of source read data. Key data are extracted by comparing read data in respective sectors entered in CD ROM and corrected read data by means of these error correction code data. In case these data do not coincide key data are extracted from data for their reading and storage. Key data are recorded by means of standard available hardware. EFFECT: enhanced reliability of recorded data protection, enhanced encryption stability of protection system. 3 cl, 1 dwg
