OPTICAL MEDIUM WITH ADDED DESCRIPTOR TO REDUCE COUNTERFEITING

• US 20110002209A1
• Filed: 07/03/2009
• Published: 01/06/2011
• Est. Priority Date: 07/03/2009
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Evans, David E., Kirovski, Darko
• Granted Patent: US 9,135,948 B2
• Time in Patent Office: Days
• US Class Current: 369/53.21
• CPC Class Codes: G06Q 30/018 Certifying business or products
• CPC Class Codes: G11B 20/00086 Circuits for prevention of unauthorised reproduction or copying, e.g. piracy indicating unauthorised use of record carriers in general G11B23/28; scrambling for television signal recording H04N5/913; network architectures or network protocols for network security H04L63/00; cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00
• CPC Class Codes: G11B 20/00115 wherein the record carrier stores a unique medium identifier
• CPC Class Codes: G11B 20/00123 the record carrier being identified by recognising some of its unique characteristics, e.g. a unique defect pattern serving as a physical signature of the record carrier
• CPC Class Codes: G11B 20/00173 wherein the origin of the content is checked, e.g. determining whether the content has originally been retrieved from a legal disc copy or another trusted source
• CPC Class Codes: G11B 20/0021 involving encryption or decryption of contents recorded on or reproduced from a record carrier
• CPC Class Codes: G11B 20/00579 said format change concerning the data encoding, e.g., modulation schemes violating run-length constraints, causing excessive DC content, or involving uncommon codewords or sync patterns
• CPC Class Codes: G11B 2220/2537 Optical discs

Abstract

Functionality is described for reducing the unauthorized reproduction of optical media, such as optical discs of various types. The functionality operates by adding a physical descriptor to an optical medium, forming reference descriptor information based on the descriptor, signing the reference descriptor information to produce authenticity information, and adding the authenticity information to the optical medium. At a point of consumption, the functionality operates by reading the authenticity information and reading the descriptor. Based on the information that is read, the functionality performs cryptographic analysis and descriptor-based analysis to validate the optical medium. The functionality includes various provisions to reduce the impact of wear and tear on the above-summarized analysis. The functionality can be applied to stamped or recordable optical media.

Claims

1. A method for adding authenticity information to an optical medium to reduce counterfeit duplication of the optical medium, comprising:

adding a descriptor having plural descriptor elements to the optical medium, the descriptor being produced with an intent of providing at least one data-level region having a length that produces indeterminate interpretations when read plural times;

reading the descriptor from the optical medium and forming reference descriptor information based on the descriptor, the reference descriptor information including element type information which conveys whether each descriptor element associated with the descriptor is one of;

a deterministic element, the interpretation of which is biased towards a single value;

or

a probabilistic element, the interpretation of which is not biased towards a single value;

signing the reference descriptor information to provide authenticity information; and

adding the authenticity information to the optical medium.

2. The method of claim 1, wherein said adding of the descriptor comprises adding plural descriptors to the optical medium.

3. The method of claim 2, wherein said reading of the descriptor comprises reading the plural descriptors to provide plural items of reference descriptor information and plural corresponding items of authenticity information.

4. The method of claim 1, wherein said reading of the descriptor comprises reading the descriptor based on at least two environmental conditions to provide at least two items of reference descriptor information and at least two corresponding items of authenticity information.

5. The method of claim 4, wherein said at least two environmental conditions correspond to two respective tilt conditions, each tilt condition corresponding to an orientation of a laser with respect to the optical medium.

6. The method of claim 1, wherein the method is performed in conjunction with a manufacturing operation in which the optical medium is created via a stamping process.

7. The method of claim 1, wherein the method is performed in conjunction with a burning operation in which content is added to the optical medium via a content-burning process.

8. The method of claim 1, further comprising supplying the optical medium with the authenticity information added thereto to a user in association with a separate article, the optical medium serving as a certificate of authenticity for the article.

9. The method of claim 1, further comprising, as a condition to providing the authenticity information:

assessing digital rights associated with content that is accessible to a user, to provide rights information; and

copying content onto the optical medium at a user site, as governed by the rights information,

the method allowing the user to provide an authentic copy of the content, as governed by the rights information.

10. The method of claim 1, wherein the reference descriptor information comprises a vector that expresses the element type information as a set of data items, each data item having one of two values, a first value indicating that a descriptor element is a deterministic element and a second value indicating that a descriptor element is a probabilistic element.

11. The method of claim 1, wherein the reference descriptor information comprises a vector that expresses the element type information as a set of readings, each reading indicating a number of times a descriptor element has been interpreted as a particular value, which indicates, in turn, whether the descriptor element is a deterministic element or a probabilistic element.

12. An electronic descriptor checking system, comprising:

a code reading component configured to read authenticity information from an optical medium;

an examination component configured to read a descriptor from the optical medium and form in-field descriptor information based on the descriptor, the descriptor having multiple descriptor elements, the in-field descriptor information including element type information which indicates whether each descriptor element of the descriptor is one of;

a deterministic element, the interpretation of which is biased towards a single value;

or

a probabilistic element, the interpretation of which is not biased towards a single value; and

a comparison component configured to determine whether the optical medium is valid by comparing the in-field descriptor information with reference descriptor information obtained from the authenticity information.

13. The electronic descriptor checking system of claim 12, wherein the optical medium includes plural descriptors, and wherein the comparison component is configured to determine that the optical medium is valid based on a comparison operation performed with respect to at least one of the plural descriptors.

14. The electronic descriptor checking system of claim 12, wherein the reference descriptor information includes plural items of reference descriptor information, and wherein the comparison component is configured to determine that the optical medium is valid based on a comparison operation performed with respect to at least one of the plural items of reference descriptor information.

15. The electronic descriptor checking system of claim 14, wherein the plural items of reference descriptor information include at least two items of reference descriptor information that pertain to different respective tilt conditions, each tilt condition corresponding to an orientation of a laser with respect to the optical medium.

17. The electronic checking system of claim 12, wherein the comparison component is configured to compare the in-field descriptor information with the reference descriptor information by determining a distance between the in-field descriptor information and the reference descriptor information, and then comparing the distance with a threshold.

16. The electronic descriptor checking system 12, further comprising:

a cryptographic component configured to determine whether the optical medium is valid based on a cryptographic analysis of the authenticity information, the cryptographic component producing a first result and the comparison component producing a second result; and

a final assessment component configured to assess whether the optical medium is valid overall based on the first result and the second result.

18. A method for adding authenticity information to an optical medium to reduce counterfeit duplication of the optical medium, comprising:

assessing digital rights associated with content that is accessible to a user, to provide rights information;

copying content onto an optical medium at a user site, as governed by the rights information;

adding a descriptor having plural descriptor elements to the optical medium;

reading the descriptor from the optical medium and forming reference descriptor information based on the descriptor;

signing the reference descriptor information to provide authenticity information, as governed by the rights information; and

adding the authenticity information to the recordable optical medium,

the method allowing the user to provide an authentic copy of the content, as governed by the rights information.

19. The optical medium of claim 18, wherein said assessing involves accessing a remote entity to determine the rights information.

20. The optical medium of claim 18, wherein the optical medium is a recordable-type optical medium.