Abstract: To provide an unauthorized device detection system capable of finding and specifying a device that was manufactured or altered unauthorizedly. A DVD player 400a writes its own device ID to a memory card 200a. When a user purchases content, a register device 300 reads a media ID and the device ID from the memory card 200a, and transmits the media ID and the device ID to a management server device 100. The management server device 100 calculates, based on pairs of media IDs and device IDs stored beforehand and the received pair of media ID and device ID, a total number of media IDs corresponding to the received device ID, and compares the calculated total number with a threshold value. If the total number exceeds the threshold value, the management server device 100 judges that the DVD player identified by the received device ID is an unauthorized device.

Abstract: An image processing apparatus enables image data to be handled easily after photography. A server apparatus pattern images and control information in correspondence with user identifiers. A digital camera photographs a subject, obtains a pattern image and a piece of control information from the server apparatus, and judges whether a portion of the image data obtained by photography matches the obtained pattern image. If a matching portion exists, the digital camera operations in accordance with an operation instruction included in the piece of control information. If the operation instruction is mosaic processing, the digital camera performs mosaic processing to the matching portion. If the operation instruction is image replacement, the digital camera replaces the matching portion with a predetermined image or performs CG processing on the matching portion. If the operation instruction is frame deletion, the digital camera deletes the image data.

Abstract: An unauthorized apparatus detection device, playback device, unauthorized apparatus detection system, information collection device, unauthorized apparatus detection method, a program, recording medium, apparatus information update method, and integrated circuit can detect clones of a playback device. In a management server 2, a reception processing unit 241 acquires a user terminal identifier and a first random number from a user terminal targeted for unauthorized apparatus detection, judges whether a second management server random number, which is stored in a storage unit 23 in correspondence with the user terminal identifier, matches the first user terminal random number. If the two fail to match, a display unit 22 displays a message indicating that a clone exists. If the two match, a terminal information generation unit 243 generates a new random number, and writes the generated random number as the second random number in the storage unit 23.

Abstract: A transmission device including: copy unit that extracts part or all of partial contents, as tracking information, from a content, and copies the extracted tracking information, thereby generating pieces of tracking information; candidate information obtaining unit that obtains pieces of candidate information respectively corresponding to the pieces of tracking information; evidence information obtaining unit that obtains evidence information generated dependently on a piece of candidate information selected by the reception device from among the pieces of candidate information; hash generating unit that generates hash values respectively in accordance with the pieces of candidate information; embed unit that embeds the hash values respectively into the pieces of tracking information, and embeds the evidence information into each piece of tracking information; and transmit unit that transmits each piece of tracking information in which a hash value and the evidence information have been embedded.

Abstract: A recording apparatus for copying a digital stream recorded on a first recording medium using a code format compatible with the first recording medium to a second recording medium after the digital stream has been converted to a code format compatible with the second recording medium, comprising: a detection unit operable to detect a plurality of devices that are available for distributed processing from devices connected to the recording apparatus via a network; an allocation unit operable to divide the digital stream at one or more predetermined points on a playback time axis and to allocate the divided portions to the detected devices respectively; a transmission unit operable to transmit the allocated portions to the respective detected devices; a control unit operable to control the detected devices to perform transcoding for converting a code format of the allocated portions to the code format compatible with the second recording device; and a writing unit operable to receive converted portions resultin

Abstract: A content distribution system for transferring contents between transmission device and reception device. The transmission device includes: key obtaining unit that obtains, from reception device, public keys and public key identifiers; watermark embedding unit that embeds a different public key identifier, as electronic watermark, into each of contents that are identical in substance; an encryption unit that encrypts contents using public keys to generate encrypted contents; and transmission unit that transmits encrypted contents to reception device. The reception device includes: key storage unit storing public keys, public key identifiers, and a private key that makes a pair with one of the public keys; key transmission unit that transmits public keys and public key identifiers to the transmission device; content receiving unit that receives encrypted contents from transmission device; and decryption unit that obtains a content from the received encrypted contents, using the private key.

Abstract: A computer system having resistance to timing attacks based on measuring processing times is offered. The computer system encrypts or decrypts a plain text or ciphertext via a process of converting the partial data on the plain text or the encrypted text into conversion data. A conversion table includes one piece of conversion data corresponding to the partial data at the start position of the line table area and includes data not associated with the conversion in the other position. A computer program includes: an operation instruction group for calculating the predetermined position of the corresponding conversion data in the conversion table by using the acquired partial data; and a read instruction group for reading out the conversion data from the position calculated from the conversion table.

Abstract: A personal information management device aims to save troubles of inputting passwords and deleting personal information, to prevent others from viewing the personal information, and to maintain confidentiality of the personal information even when a mobile device is lost. Personal information storage unit 201 holds encrypted personal information, key distribution unit 204 distributes a decryption key used for decrypting the encrypted personal information into a first and a second distributed keys based on a secret sharing scheme, distributed key storage unit 205 stores thereon the first distributed key, stores the second distributed key on home device 30, and deletes the decryption key. Upon decryption, link judgment unit 210 judges link establishment. Key recovery unit 207 acquires the second distributed key from home device 30, and recovers the decryption key using the first and the second distributed keys. Decryption unit 208 decrypts the encrypted personal information using the decryption key.

Abstract: An authentication system that permits the user to use a function by authenticating the user in a more reliable manner than conventional technologies. The authentication system 1 includes a user terminal 10, an authentication recording medium 20, and wireless ID tags 31, 32, 33, 34, 35, . . . 36. Upon receiving from a user an instruction to activate a function provided by the authentication system for which the access by the user is limited, the user terminal 10 collects ID codes from the wireless ID tags 31, 32, 33, 34, 35, . . . 36, and judge whether or not a level of match between the collected ID codes and the ID codes stored beforehand in the authentication recording medium 20 satisfies a predetermined condition. If the level of match satisfies the predetermined condition, the user terminal 10 activates the designated function.

Abstract: Processing load on an executing device for conducting playback is high during the playback of contents since the executing device performs verification of the contents validity in parallel with the contents playback, and therefore the executing device has to be equipped with a highly efficient processor. The present invention reduces the processing load involved in the verification by using, for the verification, only a predetermined number of encrypted units selected randomly from multiple encrypted units constituting encrypted contents recorded on the DVD. In addition, the present invention is capable of improving the accuracy of detecting unauthorized contents to some extent by randomly selecting a predetermined number of encrypted units every time the verification is performed.

Abstract: An authentication system that verifies various types of authenticity in regards with a visit by a forwarding agent. An identity authentication system is composed of an authentication card, a user terminal, and a card reader. Upon insertion of the authentication card into the card reader, the user terminal generates a random number, stores therein the generated random number, and outputs the random number to the authentication card. The authentication card generates encrypted information by encrypting the received random number using an identity certification key having been stored therein, and outputs the generated encrypted information to the user terminal. The user terminal decrypts the received encrypted information using an identity authentication key having been stored therein, and performs an authentication by judging whether or not the decrypting result matches the stored random number.

Abstract: A content-related information delivery system for delivering information related to a content to a user-owned apparatus. The system is composed of a playback apparatus and a server. The playback apparatus monitors a current playback position of the content during playback, generates playback position information specifying a segment of the content, and transmits the generated playback position information to the server. The server receives the playback position information from the playback apparatus, acquires information related to the segment of the content specified by the received playback position information, and transmits the acquired related information to the user-owned apparatus.

Abstract: The present invention is a content distribution system for distributing contents. The content distribution system (1) includes a key issuing center (11), a server (12), eight output apparatuses (13a) to (13h), and a communication path (10) that connects them to each other. Here, a pair of the key issuing center (11) and each of the output apparatuses (13a) to (13h) is previously given an individual key shared between them. For example, the key issuing center (11) shares an individual key IKa with the output apparatus (13a), an individual key IKb with the output apparatus (13b), and an individual key IKh with the output apparatus (13h).

Abstract: A key issuing center (11) distributes a system secret parameter group that is information necessary for generating a content key used for encrypting a content to a server (12), and an encrypted intermediate key group set that is information necessary for generating a content key used for decrypting the content to output apparatuses (13a to 13n). The server (12) generates the content key based on the system secret parameter group and a time varying parameter group, encrypts the content based on the content key, and distributes the encrypted content and the time varying parameter group to the output apparatuses (13a to 13n). The output apparatuses (13a to 13n) generates a content key based on the encrypted intermediate key group set and the received time varying parameter group, decrypts the encrypted content based on the content key, and outputs to outside.

Abstract: To provide a contents linkage information delivery system for use by a content provider to deliver contents in a manner that a user is allowed to acquire, according to a user request, a content that relates to another content. The present invention is directed to a contents linkage information delivery system for delivering a related content that is associated with another content. The contents linkage information delivery system is composed of a first playback apparatus for playing back the other content, a server for transmitting the related content, and a second playback apparatus for playing back the related content. The first playback apparatus, the server, and the second playback apparatus mutually communicate via a communications channel.