Abstract: An MPEG2-PS format digital stream is composed of VOBUs and each VOBU except an RDI-Pack at the top is encrypted using a content key Kc. The content key Kc is an encryption key obtained by adding a title key Kt to CCI, and then converting a time varying coefficient using the sum. Accordingly, the resulting content key Kc differs for each VOBU. Since each content key Kc is all different for such a small unit of VOBU, copyright of the digital stream is firmly protected. CCI contained in RDI-Pack represents conditional Copy Freely status which allows the digital stream to be copied on condition that the digital stream is recorded only in encrypted form.

Abstract: The present invention has an objective of realizing compatibility of an optical disk having a high resolution video signal recorded thereon and a system for reproducing the optical disk, with a conventional system for producing a standard resolution video signal. A high resolution video signal is divided by video division means into a main signal and a sub signal, and the main signal and the sub signal are MPEG-encoded. The stream of the main signal and the stream of the sub signal are divided into 1 GOP or more of frames. First interleave blocks 54 each including 1 GOP or more of the stream of the main signal and second interleave blocks 55 each including 1 GOP or more of the stream of the sub signal are recorded on an optical disk 1. A high resolution reproduction apparatus reproduces both the first and second interleave blocks to obtain a high resolution video output.

Abstract: An encryption device, a decrypting device, a secret key generation device, a copyright protection system and a cipher communication device including: a CRL memory unit memorizing a CRL, a device key ring memory unit memorizing a specific device key KD_A in every IC card used in a decrypting device, a content key memory unit memorizing a content key Kc, which is a secret key for decrypting content, and a hashing function processing unit calculating a hashing value of the CRL memorized in the CRL memory unit. The devices further including an Ex-OR unit carrying out an exclusive OR between the hashing value and the device key KD_A memorized in the device key ring memory unit, and an Enc unit encrypting the content key Kc memorized in the content key memory unit using an output value of an Ex-OR unit.

Abstract: An encryption device, a decrypting device, a secret key generation device, a copyright protection system and a cipher communication device including: a CRL memory unit memorizing a CRL, a device key ring memory unit memorizing a specific device key KD_A in every IC card used in a decrypting device, a content key memory unit memorizing a content key Kc, which is a secret key for decrypting content, and a hashing function processing unit calculating a hashing value of the CRL memorized in the CRL memory unit. The devices further including an Ex-OR unit carrying out an exclusive OR between the hashing value and the device key KD_A memorized in the device key ring memory unit, and an Enc unit encrypting the content key Kc memorized in the content key memory unit using an output value of an Ex-OR unit.

Abstract: An encryption apparatus 100a including: a CRL storage unit 111 storing a CRL; a device key ring storage unit 112 storing a device key KD_A specific to each copyright protection module 210a used by a decryption apparatus 200a; a content key storage unit 113 storing a content key Kc that is a secret key for encrypting a content; a hashing function processing unit 114 calculating a hash value of the CRL stored in the CRL storage unit 111 according to a hashing function; and an Ex-OR unit 115 obtaining an exclusive OR value between the hash value and the device key KD_A. The encryption apparatus also includes an Enc unit 116 encrypting the content key Kc using an output value from the Ex-OR unit, and storing the hash value, the encrypted content key and the encrypted content in a DVD2a.

Abstract: Conventionally, before reading content from a recording medium, a drive device and a playback device that plays back content perform device authentication, in order to verify whether the playback device is authorized or not. Once the playback device has been verified as authorized, the playback device is permitted to read any content stored on the recording medium. In view of this, a reading device is provided that limits a type of content acquirable by the playback device by permitting the playback device to read content which satisfies a specific condition and prohibiting the playback device to read other content.

Abstract: A recording type optical disk on which data is recordable includes a data recording and reproducing area for recording data therein and reproducing data therefrom, and a read-only disk identification information area for recording disk identification information for identifying the optical disk therein. In the optical disk, the disk identification information is formed by removing a reflection film that is formed on the optical disk in a strip shape. The disk identification information includes an inherent disk identifier for each optical disk, and the data recording and reproducing area includes an area for recording encrypted data therein. The encrypted data is encrypted by using information including the disk identification information for identifying the optical disk as a key.

Abstract: Four ECC blocks are recorded in a burst cutting area of an optical disc. Each ECC block is constituted by a BCA content code of 1 byte, content data length of 1 byte, and content data of 14 bytes. Of the BCA content data, the leading 6 bits are used for application ID and the remaining 2 bits are used for block number. Disc ID is stored in the content data. Since the four ECC blocks exist, the optical disc can be managed individually by four applications at the maximum. Thus it becomes possible to manage the same optical disc by a plurality of applications.

Abstract: A content protection system prevents illegal key acquisition, without checking uniqueness of device keys. The content protection system includes a key data generation apparatus and a user terminal. The key data generation apparatus converts first key data, which is for using content, based on a predetermined conversion rule, thereby generating second key data, encrypts the second key data using a device key held by valid terminals, and outputs the encrypted key data. The user terminal obtains the encrypted key data, decrypts the encrypted key data using a device key held by the user terminal, thereby generating second key data, converts the second key data based on a re-conversion rule corresponding to the conversion rule, thereby generating the first key data, and uses the content with use of the generated first key data.

Abstract: An information recording medium, such as an optical disk or the like, is provided for recording at least copyrighted content information and cipher key information. A part of the content information is scrambled and recorded in the information recording medium, and the scrambled and recorded part of the content information is obtained through scrambling using scramble key information, which is obtained by converting the cipher key information by the use of a non-scrambled part of the content information. The information recording medium has a recording area divided into a plurality of sectors. A plurality of data which the content information is divided into is recorded in the sectors. The non-scrambled part of the content information includes copy control information and a part of the content information that changes sector by sector.

Abstract: A recording medium provided with a lead-in area and a data recording area, wherein position information indicating the position of the key information is stored in the lead-in area and key information to be used for managing the copyrights of content is recorded in the data recording area. As a result, a read device can acquire the key information in the data recording area by referring to the position information in the lead-in area, even if the read device lacks a way of handling a file system to be used in the data recording area. Moreover, software for reproduction of the content can acquire the key information in the data recording area using the file system.

Abstract: A recording device performs recording on a recording medium such as a DVD, and playback compatibility of the recording medium is increased. In circumstances such as when a standard is established after the manufacture of a playback apparatus, there are playback devices that physically cannot read information for decrypting encrypted data from a predetermined area of the recording medium due to the specifications of the playback apparatus, and therefore cannot use the recording medium. In order for the recording medium to be able to be used in such a playback apparatus, the recording device reads data recorded in the predetermined area of the recording medium, and records the read data in another area that is readable by the playback apparatus.

Abstract: A content protection system prevents illegal key acquisition, without checking uniqueness of device keys. The content protection system includes a key data generation apparatus and a user terminal. The key data generation apparatus converts first key data, which is for using content, based on a predetermined conversion rule, thereby generating second key data, encrypts the second key data using a device key held by valid terminals, and outputs the encrypted key data. The user terminal obtains the encrypted key data, decrypts the encrypted key data using a device key held by the user terminal, thereby generating second key data, converts the second key data based on a re-conversion rule corresponding to the conversion rule, thereby generating the first key data, and uses the content with use of the generated first key data.

Abstract: An authentication system is provided having a revocation list generation apparatus that constructs and stores a revocation list in a tree structure, the revocation list generation apparatus being used in combination with a revocation judgment apparatus. The authentication system improves upon conventional authentication systems because the memory capacity to store a Certificate Revocation List (CRL) in order to identify revoked certificates is reduced. The tree structure corresponds to public key certificate, which are identified by leaf identifies, and nodes from a leaf that corresponds to a revoked public key certificate.

Abstract: To prevent the user from moving a content on a bound recording medium to another storage medium more than the maximum number of times permitted by its copyright holder. A recorder includes: a bound recording section for bound-recording at least one data file and at least one management information file for a content; a control section for giving an instruction to move the content to a storage medium; and a drive for recording the content's data on the storage medium. The management information file includes access information for accessing the data file. In response to the instruction to move, the bound recording section reads the data file of the content in accordance with the access information and outputs the content's data, the drive records the content's data on the storage medium, and the control section makes the access information unavailable.

Abstract: The present invention has an objective of providing an optical disk having a high resolution picture and a system for reproducing data on the optical disk, which are compatible with a conventional system for reproducing an ordinary resolution picture. A high resolution signal is divided into a main signal and a sub signal by picture division means and MPEG-encoded. The main signal and the sub signal are divided into frames each having 1 GOP or more. The resultant first interleave block 54 and second interleave block 55 are recorded alternately on an optical disk. A high resolution reproduction apparatus reproduced both the first and second interleave blocks, so that a high resolution picture is obtained. A non-high resolution reproduction apparatus reproduces only the first or second interleave block, so that an ordinary resolution picture.

Abstract: The present invention has an objective of providing an optical disk having a high resolution picture and a system for reproducing data on the optical disk, which are compatible with a conventional system for reproducing an ordinary resolution picture. A high resolution signal is divided into a main signal and a sub signal by picture division means and MPEG-encoded. The main signal and the sub signal are divided into frames each having 1 GOP or more. The resultant first interleave block 54 and second interleave block 55 are recorded alternately on an optical disk. A high resolution reproduction apparatus reproduced both the first and second interleave blocks, so that a high resolution picture is obtained. A non-high resolution reproduction apparatus reproduces only the first or second interleave block, so that an ordinary resolution picture.

Abstract: A key generation section 10 generates a key K to be used for cryptographic processing, based on an encrypted key data group EK. A key information retention/selection section 20 retains Lhe generated key and an intermediate key which was obtained when generating the key, and outputs the retained key information in accordance with selection information SEL. The key information is retained, e.g., in a storage circuit within the integrated circuitry, in a form which is not recognizable as a key. A content encryption/decryption section 30 restrains the cryptographic processing result DO from being outputted during key generation. When a heading pattern is detected during the cryptographic processing of an input signal DI, a reset/input enable signal generation circuit 60 switches an input enable signal IE to a disabled state, and outputs a reset signal RST after Lhe cryptographic processing has been completed.

Abstract: An optical disk according to the present invention is the optical disk on which secret information on unique information given to a specific optical disk manufacturer or a specific optical disk and information recorded on an infringement disk list of identifying an illegitimate optical disk manufacturer or an illegitimate optical disk are recorded in advance, and the optical disk has an area in which reproduction-only encrypted data encrypted based on the secret information and the information on the infringement disk list is recorded in advance or an area capable of recording the encrypted data to be encrypted based on the secret information and the information on the infringement disk list.

Abstract: An ECC block is constituted by RS(248,216,33). Of a data length of 216 bytes (symbols), only 16 bytes are allocated to BCA data and the remaining 200 bytes are used for fixed data having a predetermined value. Using the fixed data of 200 bytes and the BCA data of 16 bytes, parities of 32 bytes (symbols) are calculated. Only the BCA data of 16 bytes and the parities of the former 16 bytes of the 32-byte parities, that is, a total of 32 bytes only, are recorded in a burst cutting area of an optical disc. In decoding, error correction processing is carried out by using the fixed data of 200 bytes. The unrecorded parities of 16 bytes are processed as having been erased. Thus, the error correction capability in a burst cutting area of an optical disc can be improved.