Disc signature for disc authentication

Recordable or rewriteable record medium, comprising pre-formatted recording density information to obtain storage areas with respective corresponding standard latencies after recording data onto the record medium, wherein latency is the waiting time from the request of data stored in a storage area to the receiving of the requested data, wherein the pre-formatted recording density information indicates that a respective latency of at least a part of said different storage areas is altered in respect to a respective corresponding standard latency, characterized in that said pre-formatted recording density information indicates a pattern of storage areas with altered latencies that are respectively altered such that the respective alteration of the latency of a storage area lies within a measurement noise of latency measurements in respect to the standard latency of said storage area when the measurement is performed with a reading device for accessing said record medium.

Emulator for a record medium comprising storage areas with respective corresponding standard latencies, wherein latency is the waiting time from the request of data stored in a storage area to the receiving of the requested data, and wherein a respective latency of at least a part of said storage areas is emulated to be altered in respect to the respective corresponding standard latency, characterized by emulating a respective latency of said different storage areas to show a pattern of storage areas with altered latencies such that the respective alteration of the latency of a storage area lies within a measurement noise of latency measurements in respect to the standard latency of said storage area when the measurement is performed with a reading device for accessing said record medium, wherein the emulation is based on a key defining the alterations of the respective latency of the pattern of storage areas in respect to their standard latencies.

(canceled)

Method for producing a record medium or recording data on a record medium, said method comprises to produce or indicate different storage areas with respective corresponding latencies on said record medium, wherein latency is the waiting time from the request of data stored in a storage area to the receiving of the requested data, and wherein a respective latency of at least a part of said storage areas is altered in respect to a respective corresponding standard latency, characterized by the step of:

• determining a pattern of storage areas to be produced or indicated that have altered latencies and respectively altering the latencies of these storage areas such that the respective alteration of the latency of a storage area lies within a measurement noise of latency measurements in respect to the standard latency of said storage area when the measurement is performed with a reading device for accessing said record medium.

Method for verifying a record medium comprising different storage areas with respective corresponding latencies, wherein latency is the waiting time from the request of data to the receiving of the requested data, characterized by the step of:

• determining a pattern of storage areas that have altered latencies that are respectively altered such that the respective alteration of the latency of a storage area lies within a measurement noise of latency measurements in respect to the standard latency of said storage area when the measurement is performed with a reading device for accessing said record medium by a correlation process in which the latencies of said pattern of storage areas that have altered latencies is correlated with a key used to produce the altered latencies.