Record carrier for storing a digital work
AssigneeKoninklijke Philips Electronics N.V.
InventorAntonius Adriaan Maria Staring
Life of this patent
Estimating the term…
Abstract
A record carrier for storing a digital work (DW) includes access information (KLT) for gaining access to the digital work and a secondary channel (HC) in which secondary channel information (KLK) is stored which is used for encrypting, decrypting or verifying the access information (KLT). In order to prevent, hinder or discourage tampering with the access information (KLT), the secondary channel (HC) is stored on the record carrier on substantially the same physical location as the access information (KLT). In a preferred embodiment, the secondary channel information (KLK) is changed when the access information (KLT) has changed. This realizes a record carrier for which a replay-attack is prevented.
Claims11
A non-transitory machine-readable record carrier storing a digital work, said record carrier comprising:
- a first data area at a first physical location on the record carrier storing machine-readable access information controlling access to the digital work, and
- a second, re-writable data area comprising a secondary channel and located substantially at the first physical location on the record carrier, the secondary channel storing secondary channel information used for encrypting, decrypting or verifying the access information, wherein the secondary channel information is re-written when the access information has changed.
A method for recording a digital work on a record carrier, the method comprising the following steps:
- recording the digital work on the record carrier;
- recording access information for gaining access to the digital work and a secondary channel in which re-writable secondary channel information is stored which is used for encrypting, decrypting or verifying the access information on the record carrier, the secondary channel and the access information being recorded at substantially the same physical location on the record carrier, wherein the secondary channel information is re-written when the access information has changed.
A device for recording a digital work on a record carrier, the device comprising:
- first recording means for recording the digital work on the record carrier;
- and
- second recording means for recording access information for gaining access to the digital work and a secondary channel in which re-writable secondary channel information is stored which is used for encrypting, decrypting or verifying the access information on the record carrier, the second recording means recording the secondary channel and the access information at substantially the same physical location on the record carrier, wherein the secondary channel information is re-written when the access information has changed.
A device for reading a record carrier for storing a digital work, wherein the record carrier comprises access information for gaining access to the digital work, and a secondary channel in which secondary channel information is stored which is used for encrypting, decrypting or verifying the access information, wherein the secondary channel is stored on the record carrier at substantially the same physical location as the access information, the device comprising:
- first reading means for reading the digital work from the record carrier:
- and
- second reading means for reading access information for gaining access to the digital work and a secondary channel in which secondary channel information is stored which is used for encrypting, decrypting or verifying the access information from the record carrier, the secondary channel and the access information being stored at substantially the same physical location on the record carrier, wherein the secondary channel information is re-written when the access information has changed.
Dependencies are inferred from the claim text.