Recordable storage medium with protected data area

摘要

The invention relates to a method of storing data on a rewritable data storage medium, to a corresponding storage medium, to a corresponding recording apparatus and to a corresponding playback apparatus. Copy-protective measures require that on rewritable storage media some data must be stored which shall not be modifiable or erasable by consumer end products. A practical problem is the storage of large quantities of such data in a fixed data area. Typically the capacity is limited to a few bits. Meanwhile the amount of copy protection data that needs to be stored may well exceed the storage capacity available in the read-only fixed data area. The invention therefore proposes to write the copy protection data as system data in the recordable data area ( 4 ), e.g. as part of the formatting of the medium ( 1 ). A cryptographic summary is computed and also stored in the recordable data area ( 32 ) or in the fixed data area ( 2 ) such that a cryptographic relationship between the fixed data area ( 2 ) and the system data area ( 3 ) is provided. A playback or replay apparatus will only accept a storage medium with a valid combination of copy protection data and fixed data.