RECORD CARRIER WITH DISTRIBUTED DECRYPTION INFORMATION

摘要

The invention relates to a system for improved copy protection comprising a record carrier like a CD-RW+ or a DVD storing copy-protected information and a device for reading from and/or writing to the record carrier. For that the record carrier (1) has a first area (3) storing information (data), which is at least partly stored in encrypted form (EAK(data)), this part being called an asset (EAK(data)), and which includes a first part of decryption information (HCK, EDNK(HCK)), and the record carrier (1) further has a second area (4) storing a second part of decryption information (UCID), wherein both the first (HCK) and second (UCID) parts of decryption information serve in decrypting an asset (EAK(data)). Such distribution of decryption information over at least two areas of the record carrier may further be combined with additional safety mechanisms as e.g. hidden channels, encrypted keys, counter mechanisms, and revocation lists.