Method and device for controlling distribution and use of digital works
AssigneeKoninklijke Philips N.V.
InventorsMENNO ANNE TREFFERS, ANTONIUS ADRIAAN MARIA STARING
Life of this patent
Estimating the term…
Abstract
A method and device for controlling distribution and use of a digital work stored together with an attached usage right information on a record carrier. The attached usage right information, which may be unencrypted, is verified by using a hidden information which is changed at every change of the usage right information. The hidden information may be a checksum of a data block containing the usage right information, or other encoding that may detect a change to the stored data block. Thus, a “copy and restore attack” is not successful, since it will lead to a mismatch between the hidden information and the restored usage right information.
Claims20
A device for controlling distribution and use of a digital work on a record carrier, comprising:
- a drive that enables reading and writing to the record carrier;
- and
- a controller that is configured to:
- read, from the record carrier, usage right information associated with the digital work, the usage right information defining one or more conditions that must be satisfied in order to permit a controlled distribution or use of the digital work,
- read hidden information that is stored in a hidden channel,
- use the hidden information to determine whether the usage right information is valid,
- determine whether the defined conditions in the usage right information has been satisfied, and
- if the usage right information is valid and the defined conditions have been satisfied:
- permitting the distribution or use of the digital work,
- updating and storing the usage right information on the record carrier to reflect the permitted distribution or use, and
- updating and storing the hidden information in the hidden channel based on the updated usage right information;
- if the usage right information is not valid or the defined conditions have not been met, refusing the distribution or use of the digital work;
- wherein:
- the hidden information can only be stored in the hidden channel by the device, and
- the usage right information is stored in an unencrypted form on the record carrier.
A record carrier for storing a digital work and a usage right information defining one or more conditions that must be satisfied in order for the usage right to be exercised, wherein:
- the usage right information is stored on the record carrier in an unencrypted form, and
- the record carrier includes a hidden channel that cannot be written to by a commercial reproducing devices,
- wherein the hidden channel stores hidden information that is used for verifying the usage right information, and is changed when the usage right is exercised.
A method of controlling a device that reads and writes information on a record carrier to control distribution or use of a digital work stored on the record carrier, comprising:
- reading, from the record carrier, usage right information associated with the digital work, the usage right information defining one or more conditions that must be satisfied in order to permit a controlled distribution or use of the digital work,
- reading hidden information that is stored in a hidden channel,
- using the hidden information to determine whether the usage right information is valid,
- determining whether the defined conditions in the usage right information has been satisfied, and
- if the usage right information is valid and the defined conditions have been satisfied:
- permitting the distribution or use of the digital work,
- updating and storing the usage right information on the record carrier to reflect the permitted distribution or use, and
- updating and storing the hidden information in the hidden channel based on the updated usage right information;
- if the usage right information is not valid or the defined conditions have not been met, refusing the distribution or use of the digital work;
- wherein:
- the hidden information can only be stored in the hidden channel by the device, and
- the usage right information is stored in an unencrypted form on the record carrier.
Dependencies are inferred from the claim text.