Abstract: Contents data that have been enciphered and transmitted are recorded as they are on a recording medium, and the contents key used to encipher these data is enciphered in a way used in this recording system and is recorded on the medium. Moreover, a step is taken to ensure that fine trick plays can be performed. In recording contents data that have been enciphered and transmitted, the contents data themselves are recorded in the enciphered state on the recording medium. However, the contents data are decoded by a contents data decoding circuit 46, and a map file containing necessary management information for reproduction is created by a map file creating circuit 47 and this file is recorded together with the contents data.

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 produced so as to include a plurality of subtrees that are grouped in accordance with categories and managed by category entities. An EKB is produced so as to include data produced by selecting a path in the key tree and encrypting an upper-level key in the selected path using a lower-level key in the selected path. The resultant EKB is provided to a device. If a change occurs in state of a category tree capable of processing an EKB identified in the EKB type definition list, a notification of the change in state is sent to an entity that uses the EKB thereby making it possible for an EKB requester to perform processing in accordance with a newest EKB.

Abstract: When the recording mode of an information recording/playback device is a cognizant mode which analyzes embedded copy control information, the information recording/playback device performs content encryption using a content-encryption key generated by using a cognizant key as a content-encryption-key generating key in the cognizant mode. When the recording mode of the information recording/playback device is a non-cognizant mode which does not analyze the embedded copy control information, the information recording/playback device performs content encryption using a content-encryption key generated by using a cognizant key as a content-encryption-key generating key in the non-cognizant mode. By using these techniques, the above two recording modes are clearly distinguished and separately executed. This prevents an encryption mode indicator as copy control information and embedded copy control information from being mismatched.

Abstract: A block key to encrypt block data is generated using an ATS (arrival time stamp) appended to each of TS (transport stream) packets included in a transport stream correspondingly to the arrival time of the TS packet. The ATS is a random data depending upon an arrival time, and so a block-unique key can be generated, which enhances the protection against data cryptanalysis. A block key is generated from a combination of an ATS with a key unique to a device, recording medium or the like such as a master key, disc-unique key, title-unique key or the like. Since an ATS is used to generate a block key, any area for storage of an encryption key for each block may not be provided in a recording medium.

Abstract: A method and system for transferring information using an encryption mode indicator (EMI). The present invention provides several secure information communication modes in which data (e.g., representing an audio/visual work) can be transmitted from a source device to a sink device (receiving station) in a number of secure modes. In one secure mode, EMI mode A, the information of the transmission is not allowed to be copied as a whole work; this is the highest level of copy protection. In second secure mode, EMI mode B, the information of the transmission is allowed to be copied once and once only by the sink device. In a third transmission mode, no encryption is used and free copying is available.

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 pe-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: 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 produced so as to include a plurality of subtrees that are grouped in accordance with categories and managed by category entities. An EKB is produced so as to include data produced by selecting a path in the key tree and encrypting an upper-level key in the selected path using a lower-level key in the selected path. The resultant EKB is provided to a device. If a change occurs in state of a category tree capable of processing an EKB identified in the EKB type definition list, a notification of the change in state is sent to an entity that uses the EKB thereby making it possible for an EKB requester to perform processing in accordance with a newest EKB.

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: When a player cannot play back data because a master key held by the player has a generation older than the generation of a master key having been used for recording the data, or when a recorder cannot record data because a master key held by the recorder has a generation older than the generation of a master key necessary for recording to a recording medium, the user is prompted to renew the master key for acquisition of the necessary master key, thereby enabling the data playback or data recording. The renewed master key is distributed in such a form that can be processed by a specific device via a transmission medium such as a recording medium, network, IC card, telephone line, for example, via a tree-structured distribution system.

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: 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 circuits, using the key information from a terminal, for taking out the original playback mode information at a terminal.

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 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: 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: The invention provides an enciphering apparatus and method, a deciphering apparatus and method and an information processing apparatus and method by which illegal copying can be prevented with certainty. Data enciphered by a 1394 interface of a DVD player is transmitted to a personal computer and a magneto-optical disk apparatus through a 1394 bus. In the magneto-optical disk apparatus with which a change to a function is open to a user, the received data is deciphered by a 1394 interface. In contrast, in the personal computer with which a change to a function is open to a user, the enciphered data is deciphered using a time variable key by a 1394 interface, and a result of the decipherment is further deciphered using a session key by an application section.

Abstract: An information processing apparatus and an information processing method capable of preventing information from being copied illegally. where a hash function and a service key are stored in advance in an EEPROM of a DVD player serving as a source. In an BEPROM of a personal computer (PC) serving as a sink, on the other hand, its ID and a license key are stored beforehand. The DVD player requests the PC to transmit the ID. The DVD player then applies the hash function to data resulting from concatenation of the lID with the service key to generate a license key (=hash (ID ?service_key)). Subsequently, the DVD player generates a source side common session key and encrypts the session key by using the generated license key. Then, the DVD player transmits the encrypted source side common session key to the PC.

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 15P is data-converted for ciphering by a playback mode information appendage circuit 14 in a header appendage circuit 13 responsive to the key information from a terminal 15K 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 26 in a header separation circuit 25, using the key information from a terminal 27K, for taking out the original playback mode information at a terminal 27P.

Abstract: An information recording medium 1 is provided with: a user data recording part 3 which records user data; a random-pattern-information recording part 4 which records random pattern information from a random physical phenomenon; and an authentication data recording part 5 which records, as authentication data, medium identification information created on the basis of the random pattern information detected from the random-pattern-information recording part 4 and a digital signature for each manufacturer with respect to the medium identification information.

Abstract: An information recording medium 1 is provided with: a user data recording part 3 which records user data; a random-patter-information recording part 4 which records random pattern information from a random physical phenomenon; and an authentication data recording part 5 which records, as authentication data, medium identification information created on the basis of the random pattern information detected from the random-pattern-information recording part 4 and a digital signature for each manufacturer with respect to the medium identification information.

Abstract: An information recording/playback device stores beforehand, on a recording medium, secret information in which a writing/reading method thereof cannot be analyzed and which can be read only by a special reading method. The secret information is applied to a key for content encryption or decryption when performing recording or playback of contents on the recording medium, such as music data and image data. The secret information is, for example, a stamper ID. By using the stamper ID as secret information, and a master key and a media key which are distributed in a tree-structure key-distribution system, a content-cryptosystem key is generated. Accordingly, each content is allowed to be used in only an appropriate device in which the special reading method for the secret information can be executed and to which the key is distributed by the tree-structure key-distribution system.