Abstract:
A method and apparatus for controlling access to a storage medium (20), such as an optically readable medium, Light sensitive or other materials (21) that are adapted to change state and affect reading of a storage medium (20) are used to control access to data that may be stored on optical medium and/or to control use of the medium (20).
Abstract:
In order to distinguish a duplicated record carrier from an original record carrier a pattern is included in a ROM type record carrier that is oriented perpendicular to the reading direction. During illegal duplication the spatial relationship is disturb which can be easily detected. The patterns can be read out simultaneously by the same single read-out spot by including both patterns within the diameter of the optical spot thus guaranteeing that the read-out patterns are actually still spatially close together. Special patterns can be used that allow an easy detection of disturbances caused by the illegal duplication.
Abstract:
Record carrier identification information is stored using an asymmetry modulation (figs. 1,2,3). This prevents the access to this information throught the regular data path (65) of the playback device (60). The asymmetry information is automatically removed by the playback device because of the inherent data slicing fig. 4) and decoding that takes place in the play back device.
Abstract:
The invention relates to an information carrier for holding user information, the information carrier comprising access information in the form of access information bits for accessing the user information, the access information bits being stored on the information carrier in a variation of a parameter, which variation is detectable by integration detection. The access information bits are scrambled according to a pre-determined scrambling method. By scrambling the access information bits according to a pre-determined scrambling method detection of the access information is not possible as long as the scrambling method is not known. Using the integration detection technique only results in the access information is one knows how the signal obtained after reading-out the area comprising the access information bits must be processed. In this way illegal retrieval of the user information is further prevented.
Abstract:
Die Erfindung betrifft ein Verfahren zum Schutz von auf einem Datenträger befindlicher Software vor unberechtigter Anfertigung von Kopien oder unberechtigter Mehrfachinstallation auf verschiedenen Computern sowie auf mit einem Kopierschutz versehene Datenträger, insbesondere solche, die auf dem erfindungsgemässen Verfahren beruhen. Das Verfahren beruht darauf, dass verschiedene für die Installation der Software auf dem Datenträger befindliche Bereiche (1, 2) zu unterschiedlichen Zeiten lesbar bzw. unlesbar gemacht werden. Dies kann insbesondere durch Aufbringen verschiedener Beschichtungen auf verschiedene Bereiche (1, 2) des Datenträgers geschehen, die sich im Laufe des Installationsvorgangs so umwandeln lassen, dass die Beschichtungen, die zunächst das Lesen des Datenträgers erlaubt haben, dies anschliessend verhindern, während die Beschichtungen, die zunächst das Lesen des Datenträgers verhindert haben, dies anschliessend erlauben. Zweckmässigerweise ist eine Installation der Software nur dann möglich, wenn bei Lesbarkeit mindestens eines Bereiches (1, 2) des Datenträgers mindestens ein anderer Bereich (2, 1) des Datenträgers unlesbar ist.
Abstract:
A storage medium (800) capable of being read by player (900), the storage medium comprising: digital content disposed along one or more tracks (104) of the storage medium; and an authentication program (808) disposed along the one or more tracks of the storage medium for authenticating (1000, 1100) the storage medium by determining whether the one or more vague bits (330, 332, 424, 426, 428, 524, 526, 528, 624, 626, 628, 724, 726, 728) exist at the one or more predetermined locations (810). There are also provided a method for authenticating (1000, 1100) a storage medium and a method for crating (1200, 1300, 1400) a storage medium having the one or more vague bits.
Abstract:
Methods and apparatus are provided for making an optically readable storage media in which the reading beam passes through a bonding layer configured with a reactive material that transforms from an optically transparent state to an optically opaque state after exposure to a predefined stimulus, thereby inhibiting access to the data encoded on the optically readable storage media. The method includes steps of synthesizing a blocked dye combining the blocked dye with a carrier material curing the resultant combination deblocking the dye to produce a reduced dye in the resultant bonding layer exposing the optically readable storage media with the reactive material in its bonding layer to a predetermined stimulus. In a further aspect of the present invention methods and apparatus are provided for making an optically readable storage media wherein the reading light passes through the bonding layer and the data encoded information is encoded on the L1 substrate. In yet another aspect of the present invention methods and apparatus are provided for making an optically readable storage media with at least two mechanisms for limiting access to the encoded data of the optically readable storage media.
Abstract:
The invention relates to a method for decrypting encrypted data stored on a record carrier, to a corresponding method for encrypting data and to corresponding apparatuses. In order to provide a high level of protection for data stored on a record carrier and to prevent that data stored on different record carriers can be decrypted after a decryption algorithm has become known the method for decrypting encrypted data according to the invention comprises the following steps: a) generating a decryption key (DK) using a unique carrier identifier (UDI) associated with said record carrier, a hidden key (HK) stored in a hidden channel on said record carrier and a password key (PK), and b) decrypting said encrypted data stored on said record carrier using said generated decryption key (DK).