Abstract: Disclosed is an optical disk barcode forming method wherein, as information to be barcoded, position information for piracy prevention, which is a form of ID, is coded as a barcode and is recorded by laser trimming on a reflective film in a PCA area of an optical disk. When playing back the thus manufactured optical disk on a reproduction apparatus, the barcode data can be played back using the same optical pickup.

Abstract: An output bit sequences is derived from an initial bit sequence and this output bit sequence is used to encrypt an input bit sequence in a first mode of operation or not to so encrypt the input bit sequence in a second mode of operation. The mode of operation is switched automatically whenever the output bit sequence contains a predetermined trap bit sequence. As a result of this automatic switching between such encryption and no such encryption, unauthorized determination of secret codes is thwarted.

Abstract: The present invention has an object to overcome problems of a key recovery system using a conventional KRF system and to achieve efficient operation of the overall key recovery system. A key recovery system of the present invention includes check units 12a, 12b for checking whether a user has a recovery authorization for a common key KS, on the basis of a recovery condition RC specified by a recovery condition index RCI which is added to an encrypted message (encrypted message obtained by encrypting the common key KS with a public key KRCpub) supplied from a terminal (10a to 10d) of the user concerned, and a key recovery control unit 14 which is provided separately from the check units 12a, 12b and decrypts the encrypted message with a private key KRCpri paired with the public key KRCpub to recover the common key. The check unit 12a, 12b supplies the common key KS recovered in the key recovery control unit 14 to the user concerned only when the user has the recovery authorization.

Abstract: The invention makes it possible to properly certify a genuine owner, and to inhibit deterioration of image quality of media information to which an embedding operation is performed by adaptively determining amount of embedding for characteristic values such as pixel values. It includes a data hiding method for embedding message data into media data comprising the steps of obtaining a secondary key by inputting a key having a predetermined value to a specified function; determining hiding positions in which the message data will be embedded according to the obtained secondary key, and selecting one of plural hiding functions according to the secondary key so that the selected hiding function is used for each of the determined hiding positions; and embedding the message data into each of the determined hiding positions according to the selected hiding function corresponding to the hiding position.

Abstract: A system and method are provided for using a second resource to store a data element from a first resource in a stack. A data element XN'1 and a signature S[N] are signed at a first resource to obtain a signature S[XN+1,S[N]], where N is an integer. The data element XN+1 and the signature S[N] are sent from the first resource to the second resource to be stored in a stack. The signature S[XN+1,S[N]] is stored at the first resource.

Abstract: A personal computer having a security function is provided.

Abstract: Improved key management is provided by a public key replacement apparatus and method for operating over insecure networks. An active public key and the mask of a replacement public key are provided by a key server to nodes where the active key is used to encrypt and verify messages. To replace the active public key with the replacement public key, a key replacement message is sent to the node. The key replacement message contains the replacement public key and contains the mask of the next replacement key. The mask of the replacement public key may be generated by hashing or encrypting. The key replacement message is signed by the active public key and the replacement public key. Nodes are implemented by a computer, a smart card, a stored data card in combination with a publicly accessible node machine, or other apparatus for sending and/or receiving messages.

Abstract: A method and apparatus for performing high-speed computation of a Montgomery value defined as 22k mod(n) for an arbitrary modulus n is disclosed. After loading the value of 2(h*m)+1 into a first register and the value of the modulus n in a second register, the bits of modulus n are shifted in a most significant bit direction before a repeated modular reduction and squaring process. This allows the computation of the Montgomery value for modulus values of arbitrary sizes while reducing the number of computations required by a processor with a limited operand size.

Abstract: A system and method are provided for storing a data element from a first resource in a queue at a second resource. A combination of a data element XN+1 and a signature SQ=S[N] are signed at a first resource to obtain a signature S[XN+1,S[N]], where N is an integer. The data element data element XN+1 and the signature S[XN+1,S[N]] are sent from the first resource to the second resource to be stored in the queue at the second resource. The signature S[XN+1,S[N]] is stored at the first resource as the new value for SQ.

Abstract: Data is recorded on an optical disk. In a prescribed region of the disk, an identifier is provided for indicating whether a barcode-like mark is present or not on the disk. The identifier and the barcode-mark are in different locations on the disk. At least a portion of the barcode-like mark overwrites a pre-pit area of the disk.

Abstract: A memory containing an authenticated search tree that serves for authenticating membership or non membership of items in a set. The authenticated search tree including a search tree having nodes and leaves and being associated with a search scheme. The nodes including dynamic search values and the leaves including items of the set. The nodes are associated, each, with a cryptographic hash function value that is produced by applying a cryptographic hash function to the cryptographic hash values of the children nodes and to the dynamic search value of the node. The root node of the authenticated search tree is authenticated by a digital signature.

Abstract: A wireless data platform (10) comprises a plurality of processors (12, 16). Channels of communication are set up between processors such that they may communicate information as tasks are performed. A dynamic cross compiler (80) executed on one processor compiles code into native processing code for another processor. A dynamic cross linker (82) links the compiled code for other processor. Native code may also be downloaded to the platform through use of a JAVA Bean (90) (or other language type) which encapsulates the native code. The JAVA Bean can be encrypted and digitally signed for security purposes.

Abstract: An apparatus and method for detecting erroneous initialization vectors transmitted over a communications channel and maintaining cryptographic synchronization by comparing a received vector with a predicted correct vector. The vectors are random-like in nature by utilizing a pseudo-random number generator having a long overall cycle length. If the level of bit errors of the comparison is relatively small, considering the predicted vector is considered correct and used for synchronization, but if the number of bit errors of the comparison is relatively large, the predicated vector is considered in correct.

Abstract: Data is recorded on an optical disk. In a prescribed region of the disk, an identifier is provided for indicating whether a barcode-like mark is present or not on the optical disk. The identifier and the barcode-like mark are in different locations on the disk. The barcode-like mark has a plurality of bars. Each of the bars extends in a radial direction. The optical disk is constructed from two disk substrates.

Abstract: A method of automatically detecting a data format type of a stream of data. A determination is made as to whether a current word and a previously received words comprise a set of identifiers associated with a selected type of data. When a preselected number of detections of the set of identifiers has been reached within a predefined time period, the input stream is declared to be the selected type of data. Simultaneously, when the selected type of data is not detected, other data types are sequentially selected for similar checking. This successive selection of different data types allows the method to classify the input data into one out of multiple data types.

Abstract: On an optical disk, data is recorded. In a prescribed region of the disk, an identifier is provided for indicating whether or not a barcode-like mark is present on the optical disk. The identifier and the barcode-like mark are in different locations on the disk. The prescribed region is a control data area in which physical feature information regarding the optical disk is recorded. The prescribed region is also a guard bond area in which at least an address is recorded.

Abstract: Data is recorded on an optical disk. In a prescribed region of the disk, an identifier is provided for indicating whether a barcode-like mark is present or not on the disk. The identifier and the barcode-mark are in different locations on the disk. A control area, in which physical feature information regarding the disk is recorded, is included in the prescribed region.

Abstract: In an encrypted transmission system composed of one transmission apparatus 10 and twenty-eight reception apparatuses A1-G4 that are classified into seven groups A-G, two secret key exclusively selected out of a total of fourteen secret keys are distributed beforehand to each group. The transmission apparatus 10 encrypts the same message M using one of the two secret keys distributed to each group and sends each group a message M encrypted with one of the group's secret keys. The reception apparatuses each decrypt the received cryptogram separately using each of the secret keys assigned to the of group to which each reception apparatus belongs, judge whether either of the two decryption results conforms to a predetermined rule, and specify the correct decryption result.

Abstract: A process for the identification of a claimant by a verifier. The process is of the public key type, where the public exponent is equal to 3. The claimant draws at random a first exponent .alpha., calculates r=g.sup..alpha. mod n and transmits R=r.sup.3. The verifier draws at random a second exponent .beta., calculates t=g.sup..beta. mod n, calculates T=t.sup.3 mod n and h=H.sub.1 (Z), where H.sub.1 is a hash function, and calculates Z=R.sup.3 mod n. The verifier transmits to the claimant the numbers T and h. The claimant calculates Y=T.sup..alpha. mod n, verifies the result H.sub.1 (Y), calculates H=H.sub.2 (Y), where H.sub.2 is another hash function, calculates z=rS mod n, and transmits z and H. The claimant also has a secret number S equal to the modulo n cubic root of a number I deduced from its identity so that the number S verifies S.sup.3 =I mod n. The verifier verifies that H received is equal to H.sub.2 (Z) and that z.sup.3 is equal to RI mod n.

Abstract: A decryption scheme is provided for encrypted configuration bitstreams in a programmable logic device. One embodiment includes circuitry for altering a decryption key for a plurality of encrypted bitstream portions, thereby providing a high level of security of the circuit layout embodied in the bitstream.