Abstract: A cipher key is generated by first information shared in secrete between a data transmitting unit 10 and a data receiving unit 20, second information derived from duplication control information of transmit data and third information which is time change information shared between the data transmitting unit and the data receiving unit to cipher data by a CPU 12 by using the above-mentioned cipher key to transmit, from the data transmitting unit 10 to the data receiving unit 20, transmit data in which the duplication control information and the time change information are added to the ciphered data.

Abstract: An enabling key block (EKB) used in an encrypted key distributing tree structure is generated by forming a simplified 2-branch or multi-branch type tree with a terminal node or leaf which is capable of decrypting on the basis of a key corresponding to a node or a leaf of the Simplified tree. Further, the EKB includes a tag for indicating a position of an encrypted key in the tree. The tag not only discriminates position but also stores data for judging the presence of encrypted key data within the EKB. As such, a considerable reduction in data quantity is realized, and the decrypting process in a device is also simplified.

Abstract: A signal transmission method applicable to prevention of modification or alteration of the playback mode information, such as copying management information or charging information. The playback mode information form a terminal is data-converted for ciphering by a playback mode information appendage circuit in a header appendage circuit responsive to the key information from a terminal and the resulting information comprised of the data and the playback mode information is outputted. The reproducing side effects data conversion on the ciphered playback mode information for deciphering, by a playback mode information detection circuit in a header separation circuit, using the key information from a terminal, for taking out the original playback mode information at a terminal.

Abstract: A content key, an authentication key, and a program data etc. are transmitted with an enabling key block (EKB) in an encrypted key constitution of a tree structure. The EKB has a constitution in which a device as a leaf of the tree holds a leaf key and a limited node key, and a specific enabling key block (EKB) is generated and distributed to a group specified by a specific node to limit devices that can be renewed. As the devices that do not belong to the group cannot perform decryption, the security for distributing keys etc. can be secured. Thus, distribution of various kinds of keys or data is executed in an encryption key constitution of a tree structure to realize an information processing system and method enabling to distribute data efficiently and safely.

Abstract: A virtual machine can be implemented by anyone because the interface and other information necessary for implementation are publicly available. Hence, if virtual machine is implemented maliciously, a program operating thereon can be made to operate maliciously instead of operating legitimately. By comparing secret information held in memory and specific to the virtual machine with verification information which a program holds itself, the program verifies that the virtual machine on which it is running has been legitimately implemented and excludes illegitimate virtual machines.

Abstract: A signal recording/reproducing method and apparatus, signal record medium and signal transmission/reception method and apparatus, whereby a signal recorded on a signal record medium can be identified as being an original signal or a copied signal. A CPU 11 generates, at a pre-set time interval, an identification signal having a meaning at a pre-set time interval, and an identification signal addition circuit 3 adds the identification signal to the video signals and/or the audio signals. A sector forming circuit 5 and circuit components up to a recording/reproducing head 14 record the video signals and/or the audio signals and the ancillary identification signal on an optical disc 12.

Abstract: Based on the detailed reproduction control information defining the reproduction control state of data to be transmitted, the CPU 12 of the data transmission apparatus creates a simplified reproduction control information roughly defining the reproduction control state of the data, stores the simplified reproduction control information of the data in the packet header of a data packet carrying the data, stores the detailed reproduction control information in the data, and transmits the simplified reproduction control information and the detailed reproduction control information as well as the data to the data receiving apparatus 20 through the transmission channel 30 from the input-output interface 16.

Abstract: An information processing system and method are disclosed in which information processing is performed in a highly efficient manner using an enabling key block (EKB) on the basis of a tree structure including category subtrees. A key tree is formed so as to include a plurality of subtrees serving as category trees categorized in accordance with categories and managed by category entities. An EKB includes data produced by selecting a path in a tree and encrypting a higher-level key in the selected path using a lower-level key in the selected path. The resultant EKB is provided to a device. Distribution of EKB's is managed on the basis of an EKB type definition list representing the correspondence between an EKB type identifier and one or more identification data identifying one or more category trees that can process an EKB of an EKB type specified by the EKB type identifier.

Abstract: A system and method are realized which enables valid use of content by preventing unauthorized use of content which is caused by rewriting rights data. A structure is employed in which rights data including use-restriction information on content and DRM data including an encrypted content key are recorded in a digital data recording medium (media), and in which an integrity check value (ICV) for the DRM data can be stored in a recordable/playable area (protected area) by using only a dedicated IC. EKB distribution is used to execute the tree-structure key distribution to distribute keys for generating ICV-generation verifying keys. In this structure, unauthorized use of content by rewriting of the rights data is prevented.

Abstract: A data transmitting method, a data recording apparatus, a data record medium and a data reproducing apparatus are provided to disallow the encryption to be easily decoded and keep the secrecy of key information higher. The data transmitting apparatus includes an error correction coding process block. In the block, an input converting circuit operates to perform a logic operation with respect to the information data from an interface circuit 12 according to the key data. The converted information data is sent to an encoder 15 for generating parity data. This parity data is mixed with information data before conversion in a mixing circuit. The error correction coding block operates to send the resulting data to a modulating circuit 17 for modulating the data. The modulated data is recorded on a disk record medium.

Abstract: A data recording apparatus capable of preventing easily copying of information is disclosed with which, even if information is copied, the copied information cannot be reproduced, the data recording apparatus having a terminal to which encoder ID specific for the data recording apparatus is input, a recording unit for recording at least the encoder ID on an optical disk, and an encoding circuit for, in accordance with the encoder ID, encoding data supplied through a terminal and required to be recorded so that encoded data is, together with the encoder ID, recorded on the optical disk.

Abstract: An input is ciphered in at least one of a sector forming circuit 13, a scrambling circuit 14, a header appendage circuit 15, an error correction encoding circuit 16, a modulation circuit 17 and a synchronization appendage circuit 18, used for processing input data for forming a recording signal. Not only key for ciphering itself in the circuits but also the information as to which of the circuits has been used for ciphering becomes the key for ciphering. This realizes ciphering difficult to decode by a simplified structure.

Abstract: There are provided an information recording medium, and an information processing apparatus and method by which content usage in compliance with copyright protection is made possible in information processing devices such as a CD player and a PC. In the information recording medium, a first data storage area on which a copying prevention process is performed, and a second data storage area in which is stored an encrypted content file containing encrypted content, and encrypted key data such that key data for use in a decryption process is encrypted and which can be decrypted only in a device having a license are set. It becomes possible to play back the recorded content of a first data recording field in a playback device such as a CD player, and even in an information processing device, such as a PC, it is possible to decrypt and play back encrypted content of a second data recording field under the condition of obtaining a license.

Abstract: A data recording apparatus capable of preventing easily copying of information is disclosed with which, even if information is copied, the copied information cannot be reproduced, the data recording apparatus having a terminal to which encoder ID specific for the data recording apparatus is input, a recording unit for recording at least the encoder ID on an optical disk, and an encoding circuit for, in accordance with the encoder ID, encoding data supplied through a terminal and required to be recorded so that encoded data is, together with the encoder ID, recorded on the optical disk.

Abstract: A security module is provided in a data recording medium, data to be written to the data recording medium is encrypted with an content key different from one data to another, and the content key is safely stored in the security module. Also, the security module makes a mutual authentication using the public-key encryption technology with a drive unit to check that the counterpart is an authorized (licensed) unit, and then gives the content key to the counterpart, thereby preventing data from being leaked to any illegal (unlicensed) unit. Thus, it is possible to prevent copyrighted data such as movie, music, etc. from being copied illegally (against the wish of the copyrighter of the data).

Abstract: An information processing device, information processing method and a recording medium are provided. Storage included in the information processing device is operable to store a node key and a leaf key, the leaf key being unique to the information processing device and the node key being unique to each node of a hierarchical network of nodes having a hierarchical tree structure. A decryption processor performs decryption processing to detect whether an encrypted decryption key for decrypting encrypted data is stored in at least one of on the information processing device or on a recording medium. When the encrypted decryption key is detected, the decryption processor is operable to calculate the decryption key by decrypting the encrypted decryption key. However, when the encrypted decryption key is not detected, the decryption processor is operable to calculate the decryption key by decrypting a key block using one of the one or more node keys stored in the storage and the leaf key stored in the storage.

Abstract: An information processing system and method are disclosed in which information processing is performed using an enabling key block (EKB) in association with a tree structure including category subtrees. A key tree is produced, which include subtrees that are grouped in accordance with categories and are managed by category entities. The EKB includes data produced by selecting a path in the key tree and encrypting a higher-level key in the selected path using a lower-level key in the selected path. The EKB is then provided to a device. A requester, which requests production of the EKB, may produce a root key or may request a key distribution center (KDC) to produce a root key. If the (KDC) produces the EKB, it may also request a category entity to produce a sub-EKB.

Abstract: A virtual machine can be implemented by anyone because the interface and other information necessary for implementation are publicly available. Therefore, it is possible that by implementing the virtual machine illegitimately, programs run thereon on will be made to operate illegitimately instead of legitimately. A program compares secret information held by the virtual machine with verification information held by the program itself. The program thereby verifies whether the virtual machine that runs the program is implemented legitimately, and is able to reject an illegitimate virtual machine.

Abstract: A data recording apparatus capable of preventing easily copying of information is disclosed with which, even if information is copied, the copied information cannot be reproduced, the data recording apparatus having a terminal to which encoder ID specific for the data recording apparatus is input, a recording unit for recording at least the encoder ID on an optical disk, and an encoding circuit for, in accordance with the encoder ID, encoding data supplied through a terminal and required to be recorded so that encoded data is, together with the encoder ID, recorded on the optical disk.

Abstract: A configuration for achieving efficient content verification processing based on hash values is provided. Hash values of hash units set as segmented data of a content stored on an information storage medium are recorded in a content hash table and are stored on the information storage medium together with the content. An information processing apparatus for executing content playback executes hash-value comparison processing based on one or more randomly selected hash values. Regardless of the data amount of content, the configuration can perform hash-value determination and comparison processing based on hash units having a small amount of data, so that user equipment for executing content playback can perform efficient content verification.