Authenticating a data storage medium using predetermined inter-sector relationships
First Claim
1. A method comprising a step of formatting a data storage medium of the type in which data are stored in addressable sectors on a plurality of tracks using a predetermined profile that identifies a total number of channel bits to be recorded to the medium over each revolution of a plurality of revolutions of said medium so as to affirmatively establish a predefined relationship between physical locations of at least a first sector and a second sector prior to an initial recording of data to said at least first and second sectors, the presence of said predefined relationship between the resulting physical locations of the at least first and second sectors serving to identify the medium as an authorized copy.
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Accused Products
Abstract
A data storage medium (230, 400) and associated method (500, 520), apparatus (250, 430) and application routine (110, 524) for authenticating the medium as an authentic copy. The medium (such as a prerecorded or recordable optical disc) is formatted so that a predefined relationship is established (502) between physical locations of at least first and second addressable data sectors (220) prior to recording of data to the sectors (506). The predetermined relationship will be present in an authorized copy of the medium (330) but not in an unauthorized duplicate (332), allowing an application routine to grant or deny access (532, 534) to remaining portions of the medium based on the presence or absence of the detected relationship. The predetermined relationship is further used to embed a forensic data payload to serve as a digital fingerprint on the medium.
29 Citations
39 Claims
- 1. A method comprising a step of formatting a data storage medium of the type in which data are stored in addressable sectors on a plurality of tracks using a predetermined profile that identifies a total number of channel bits to be recorded to the medium over each revolution of a plurality of revolutions of said medium so as to affirmatively establish a predefined relationship between physical locations of at least a first sector and a second sector prior to an initial recording of data to said at least first and second sectors, the presence of said predefined relationship between the resulting physical locations of the at least first and second sectors serving to identify the medium as an authorized copy.
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14. A method comprising steps of:
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providing a profile that identifies a total number of channel bits to be recorded to a storage medium over each revolution of a plurality of revolutions of said medium during a write operation to affirmatively establish a predetermined relationship between a first physical location of a first data sector and a second physical location of a second data sector; and subsequently modulating a write signal in relation to said profile to write the respective first and second data sectors at the respective first and second physical locations thereby establishing said predetermined relationship on the medium; wherein the providing step comprises constructing a lookup table which specifies a rotational speed of the data storage medium for each revolution of the data storage medium during the subsequently modulating step, said lookup table selected so that a predetermined number of channel bits are recorded to the data storage medium over each said revolution. - View Dependent Claims (15, 16, 17, 18, 19, 20, 21, 22, 23, 24)
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- 25. A data storage medium comprising a plurality of addressable data sectors formed on a plurality of tracks, the sectors located in preselected physical locations in accordance with a profile generated prior to recording of the sectors which identifies a total number of channel bits to be recorded to the medium over each revolution of a plurality of revolutions of the medium, the profile establishing a predetermined relationship between the physical locations of at least selected sectors to identify the data storage medium as an authorized copy.
- 34. An application routine executed in a processor environment to read data from a data storage medium, the medium formatted by predetermining desired physical locations of a plurality of sectors the medium using a profile which identifies a total number of channel bits to be recorded to the medium over each revolution of a plurality of revolutions of the medium to establish a predetermined relationship between at least a first selected sector and a second selected sector prior to recording of data to the medium to locate said sectors, and by subsequently modulating a writing signal to locate said sectors on the data storage medium in the predetermined desired physical locations, wherein the application routine is configured to measure an access parameter relating to a sequential access of the at least first and second sectors, grant access to remaining sectors on the medium when the measured access parameter indicates the predetermined relationship is present on the medium, the presence of the predetermined relationship indicating that the medium is an authorized copy, and to deny access to remaining sectors on the medium when the measured access parameter indicates the predetermined relationship is not present on the medium, the absence of the predetermined relationship indicating that the medium is an unauthorized duplicate.
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38. An apparatus comprising:
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a predetermined profile stored in a memory space which specifies a total number of channel bits to be written to a data storage medium over each revolution of a plurality of revolutions of the medium; and a mechanism which applies a write signal to the medium in relation to said profile to sequentially form a first data sector and a second data sector at respective first and second physical locations on the medium, wherein the mechanism comprises; a motor configured to rotate the medium in response to a motor speed rotation signal; a write assembly which writes data to the medium during rotation of said medium in response to a write signal, wherein at least a selected one of the motor speed rotational signal or the write signal are modulated in relation to said profile; a master clock which generates a master clock signal at a first frequency; a clock divider circuit which outputs a write clock signal in response to the master clock signal, the write clock signal establishing timing of transitions in the write signal; and a programmable generator circuit which outputs the motor speed rotation signal in response to the master clock signal and the pre-generated profile.
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39. An apparatus comprising:
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a predetermined profile stored in a memory space which specifies a total number of channel bits to be written to a data storage medium over each revolution of a plurality of revolutions of the medium; and a mechanism which applies a write signal to the medium in relation to said profile to sequentially form a first data sector and a second data sector at respective first and second physical locations on the medium, wherein the mechanism comprises; a motor configured to rotate the medium in response to a motor speed rotation signal; a write assembly which writes data to the medium during rotation of said medium in response to a write signal, wherein at least a selected one of the motor speed rotational signal or the write signal are modulated in relation to said profile; a master clock which generates a master clock signal at a first frequency; a programmable generator circuit responsive to the master clock signal which outputs a write clock signal to establish timing of transitions in the write signal; and a lookup table responsive to a once-per-revolution signal from the motor which outputs values to the programmable generator circuit in relation to the pre-generated profile to adjust frequency of the write clock signal so that an exact, predetermined number of channel bits are written to the medium over each revolution of the medium.
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Specification