Patents Examined by David C. Cain
  • Patent number: 5802174
    Abstract: An optical disk D is composed of a first recording layer L.sub.1 and a second recording layer L.sub.2 each for two recording formats. Encrypted data is recorded on the first recording layer L.sub.1. Encrypting key data is recorded on the second recording layer L.sub.2. The encrypting key data is used for decoding the encrypted data. This recording makes easy reproduction of the recorded data quite difficult. If data recorded on a bit-formed portion may be reproduced by any means, the data signal recorded on the optical disk cannot be easily reproduced.
    Type: Grant
    Filed: June 27, 1996
    Date of Patent: September 1, 1998
    Assignee: Sony Corporation
    Inventors: Yoichiro Sako, Hideo Owa, Yoshitomo Osawa, Akira Kurihara, Isao Kawashima
  • Patent number: 5799091
    Abstract: According to the present invention, a single chip semiconductor devices is provided. In one version of the invention, a single chip CMOS technology architecture is used to implement all or various combinations of baseband radio transmission, baseband interfaces and filtering, source coding, source interfaces and filtering, control and supervision, power and clock management, keyboard and display drivers, memory management and code compaction, digital signal processing ("DSP") and DSP memory and radio interface functions.
    Type: Grant
    Filed: May 24, 1996
    Date of Patent: August 25, 1998
    Assignee: LSI Logic Corporation
    Inventor: Johan Lodenius
  • Patent number: 5799083
    Abstract: An event verification system comprises an input for the reception of information and an encryption algorithm to encrypt the information; an electronic recorder to record the encrypted information and a decryption algorithm to decrypt recorded information; at least one programmable memory to store at least one cryptographic key for use with the encryption and decryption algorithms; a tamperproof enclosure to protect the input and at least one programmable memory from access or alteration; and, a trusted agent to generate at least one cryptographic key to be used in conjunction with the encryption and decryption algorithms, the trusted agent programming any generated cryptographic key into at least one programmable memory for use with the encryption and decryption algorithms and, upon request, verifying the authenticity of the recorded information by decrypting the recorded information using at least one cryptographic key.
    Type: Grant
    Filed: August 26, 1996
    Date of Patent: August 25, 1998
    Inventors: Harlan Jay Brothers, Chris Hind Genly
  • Patent number: 5799088
    Abstract: A non-deterministic public key encryption system whereby a public key is generated from a private key using mathematical operations equivalent to exponentiation in finite fields. Thus an attacker is required to compute logarithms over finite fields. Encryption involves generating a random initialization key (R) which is used to (1) exponentiate the message receiver's public key (E) to produce initial values (K) for a pseudorandom binary mixture generator, and to (2) compute an open key (Q) by exponentiating an initial known generator state (a.sub.0). A ciphertext (C) is produced from plaintext (P) by clocking the mixture generator from the initial value (K) and combining the output keystream with the plaintext (P). The open key (Q) is attached to the ciphertext prior to transmission. Decryption involves extracting the open key (Q) and exponentiating this by the message receiver's private key (D) to compute (K) which is then used to set the initial value of a mixture generator.
    Type: Grant
    Filed: September 23, 1996
    Date of Patent: August 25, 1998
    Inventor: William Michael Raike
  • Patent number: 5799092
    Abstract: A self-verifying identification card having an image area which may contain a portrait, a finger print, a retinal image, or all of these together with an image signature which is derived from scanned intensity measurements taken from the image area. In the verification process, the image is scanned and aligned with respect to reference points corresponding to the original printing process which created the card, and intensity values, their averages, or any other function are compared to information provided by the image signature. Mathematical transformations, such as a one-way hash, an encryption, a compression algorithm, or a truth table may be used to encode the image signature. Alignment markers aid in scanning the image and the image signature. The use of average values aids in reducing noise and the use of comparison functions makes the process less sensitive to variations among scanners.
    Type: Grant
    Filed: February 28, 1995
    Date of Patent: August 25, 1998
    Assignee: Lucent Technologies Inc.
    Inventors: David M. Kristol, Lawrence P. O'Gorman
  • Patent number: 5796827
    Abstract: An apparatus and method are disclosed for encoding and transferring data from a transmitter to a receiver, using the human body as a transmission medium. The transmitter includes an electric field generator, a data encoder which operates by modulating the electric field, and electrodes to couple the electric field through the human body. The receiver includes electrodes, in physical contact with, or close proximity to, a part of the human body, for detecting an electric field carried through the body, and a demodulator for extracting the data from the modulated electric field. An authenticator, connected to the receiver, processes the encoded data and validates the authenticity of the transmission. The apparatus and method are used to identify and authorize a possessor of the transmitter. The possessor then has secure access to, and can obtain delivery of, goods and services such as the distribution of money, phone privileges, building access, and commodities.
    Type: Grant
    Filed: November 14, 1996
    Date of Patent: August 18, 1998
    Assignee: International Business Machines Corporation
    Inventors: Don Coppersmith, Prabhakar Raghavan, Thomas G. Zimmerman
  • Patent number: 5796830
    Abstract: A cryptographic key recovery system that is interoperable with existing systems for establishing keys between communicating parties. The sender uses a reversible key inversion function to generate key recovery values P, Q and (optionally) R as a function of a session key and public information, so that the session key may be regenerated from the key recovery values P, Q and (if generated) R. Key recovery values P and Q are encrypted using the respective public recovery keys of a pair of key recovery agents. The encrypted P and Q values are included along with other recovery information in a session header accompanying an encrypted message sent from the sender to the receiver. The key recovery agents may recover the P and Q values for a law enforcement agent by decrypting the encrypted P and Q values in the session header, using their respective private recovery keys corresponding to the public keys.
    Type: Grant
    Filed: July 29, 1996
    Date of Patent: August 18, 1998
    Assignee: International Business Machines Corporation
    Inventors: Donald Byron Johnson, Paul Ashley Karger, Charles William Kaufman, Jr., Stephen Michael Matyas, Jr., David Robert Safford, Marcel Mordechay Yung, Nevenko Zunic
  • Patent number: 5790675
    Abstract: A novel asymmetrical cryptographic schema which can be used for enciphering, signature and authentication. The schema is based on low degree public polynomial equations with value in a finite ring K.The mechanism is not necessarily bijective. The secret key makes it possible to hide polynomial equations with value in extensions of the ring K. The solving of these equations makes it possible, if one has the secret key, to execute operations which are not executable with the public key alone.
    Type: Grant
    Filed: July 24, 1996
    Date of Patent: August 4, 1998
    Assignee: CP8 Transac
    Inventor: Jacques Patarin
  • Patent number: 5790676
    Abstract: A preferred embodiment provides a radio port controller in a wireless personal communications system including a first interface module in communication with a radio port, a second interface in communication with a digital switch, and at least one switching transcoder module in communication with the first and second interface modules. A further preferred embodiment provides that the switching transcoder module includes a digital signal processor. The radio port controller preferably has a communication backplane including a plurality of slots, and each slot is preferably adapted to selectively receive either a T1 card interfacing to a T1 line or an E1 card interfacing to an E1 line.
    Type: Grant
    Filed: September 23, 1997
    Date of Patent: August 4, 1998
    Assignee: Hughes Electronics Corporation
    Inventors: Kalyan Ganesan, Ranjan Pant, Kim Goh, Barrie Saunders
  • Patent number: 5786975
    Abstract: A switching circuit especially suitable for protecting electronic components such as integrated circuits (2) from the harmful effects of ionizing radiation. The circuit comprises two switches for isolating the component (2) from its power supply, the switches conveniently being NPN transistors (TR1, TR2) and being connected either side of a decoupling capacitor (3) associated with a component (2). Because the capacitor (3) is allowed to retain its charge during power-off, no time is lost in recharging it once the power supply has been resumed.
    Type: Grant
    Filed: March 19, 1993
    Date of Patent: July 28, 1998
    Assignee: British Aerospace PLC
    Inventors: Peter H. Duncan, Glenn R. Randall
  • Patent number: 5787179
    Abstract: A scrambling method of a stream formed of a series of unit streams in succession, the unit stream including a first stream part and a second stream part located behind the first stream part. The scrambling method scrambles the second stream part by using a random number generator and includes a step of supplying predetermined data included in the first stream part and having a non-fixed value, for each of the second stream part to be scrambled, to the random number generator as an initial value. Further, a scrambling apparatus, a descrambling method and a descrambling apparatus are disclosed.
    Type: Grant
    Filed: July 19, 1996
    Date of Patent: July 28, 1998
    Assignee: Fujitsu Ltd.
    Inventors: Kiyotaka Ogawa, Kiyoshi Kohiyama, Ryota Akiyama, Kiyokatsu Iijima
  • Patent number: 5778072
    Abstract: A system and method provide transparent integration of a smart card private key operations with an existing set of encryption services and system applications. A key store manager manages user key data, and handles requests for key operations from the system applications. A user information file stores user data, including user private keys for users that do not have smart cards, and an indication of those users that have smart cards. A set of system applications interfaces with the key store manager through encryption protocol specific application programming interfaces. Users connect to the system through terminals or remote computers that may be equipped with smart card readers. For users having smart cards, the key store manager forwards to the smart cards requests for private key operations, such as encryption or decryption with the user's private key, from the system applications. In this manner the user's private key cannot be compromised by exposure to the computer system.
    Type: Grant
    Filed: July 7, 1995
    Date of Patent: July 7, 1998
    Assignee: Sun Microsystems, Inc.
    Inventor: Vipin Samar
  • Patent number: 5768389
    Abstract: A method and a system for generating and managing a secret key of a public key cryptosystem, in which the secret key is generated inside a tamper resistant device, and stored into a storage region in a personal portable device from which the secret key cannot be read out of the personal portable device, while the personal portable device is inside the tamper resistant device. Here, the secret key can be reproduced by collecting the partial secret keys from those arbitrators who judge that the secret key reproduction is appropriate. Also, the secret key is generated inside a tamper resistant personal portable device, and stored into a storage region in the tamper resistant personal portable device from which the secret key cannot be read out of the tamper resistant personal portable device. Here, the secret key can be reproduced by using the partial secret keys for constituting the secret key from all entities sharing interests with a user of the tamper resistant personal portable device.
    Type: Grant
    Filed: June 20, 1996
    Date of Patent: June 16, 1998
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventor: Shinji Ishii
  • Patent number: 5764767
    Abstract: A method for reconstructing a secret, over a public communication channel, using a perfect t-out-of-n secret sharing scheme. The scheme having a dealer which utilizes a delivering procedure for privately delivering n secret shares of the secret along with n keys to n participants that are interlinked by the channel. The scheme further having a secret reconstructing procedure for being executed by selected recipient participants, for reconstructing the secret by utilizing self secret share of the recipient participant and l-1 secret shares of the other participants. The secret reconstructing procedure includes the following steps:(i) receiving over said public communication channel l-1 encoded secret shares from the l-1 participants, respectively;(ii) decoding each one of the l-1 encoded secret shares, thereby obtaining l-1 decoded secret shares; and(iii) reconstructing the secret from the l-1 decoded secret shares and from the self secret share of the recipient participant.
    Type: Grant
    Filed: August 21, 1996
    Date of Patent: June 9, 1998
    Assignee: Technion Research and Development Foundation Ltd.
    Inventors: Amos Beimel, Ben-Zion Chor
  • Patent number: 5764761
    Abstract: In an electronic assembly, a first integrated circuit device (chip) is provided with a lock circuitry that controls operational enablement of a functional block of the chip. To unlock the lock circuitry, a "chip-key" must be supplied to the chip. The chip is also provided with chip-key output circuit for outputting a chip key associated with one or more other chips of the electronic assembly; the chip-key output circuit may be part of the functional block controlled by the lock circuitry of the same chip.
    Type: Grant
    Filed: May 7, 1996
    Date of Patent: June 9, 1998
    Assignee: Hewlett-Packard Company
    Inventor: Dominique Vicard
  • Patent number: 5764766
    Abstract: A system and method and computer program product for encrypting data communications comprising the generation of a salt at a data transmitting system and combination of the salt with a primary encryption key known at the data transmitting system and a data receiving system. The salt and the primary encryption key are hashed to produce a transmitting encryption key and a data message is encrypted with an encryption function utilizing the transmitting encryption key to produce a ciphertext message. The salt and the ciphertext message are transmitted to the data receiving system where the salt and the primary encryption key are hashed to produce a receiving decryption key and the data message is retrieved by performing a symmetrical decryption function on the ciphertext message and the receiving decryption key.
    Type: Grant
    Filed: June 11, 1996
    Date of Patent: June 9, 1998
    Assignee: Digital Equipment Corporation
    Inventor: Michael Spratte
  • Patent number: 5764764
    Abstract: A video signal format converting circuit is disclosed, comprising a signal converting matrix circuit and a filter circuit that is constructed of a time delaying device for a video signal corresponding to a standard television format. When a digital video signal corresponding to a first video signal format is converted into a second video signal format that is different from the first video signal format and then output, the time delaying device of the filter circuit is used as a delaying circuit. The output signal of the delaying circuit or the video signal corresponding to the standard television signal format is selectively output. While or after the video signal corresponding to the first video signal format is converted into the video signal corresponding to the second signal format, the video signal is modified so as to protect it from being copied.
    Type: Grant
    Filed: April 8, 1997
    Date of Patent: June 9, 1998
    Assignee: Sony Corporation
    Inventors: Yasuhide Mogi, Etsuro Yamauchi, Atsushi Narita
  • Patent number: 5764769
    Abstract: An apparatus and method produce a videotape or other recording that cannot be pre- or post-dated, nor altered, nor easily fabricated by electronically combining pre-recorded material. In order to prevent such falsification, the camera or other recording apparatus periodically receives certifiably unpredictable signals ("challenges") from a trusted source, causes these signals to influence the scene being recorded, then periodically forwards a digest of the ongoing digital recording to a trusted repository. The unpredictable challenges prevent pre-dating of the recording before the time of the challenge, while the storage of a digest prevents post-dating of the recording after the time the digest was received by the repository.
    Type: Grant
    Filed: July 31, 1996
    Date of Patent: June 9, 1998
    Assignee: International Business Machines Corporation
    Inventors: Charles Henry Bennett, David Peter DiVincenzo, Ralph Linsker
  • Patent number: 5764771
    Abstract: The present invention relates to a method of processing a digital signal of dimension k, in a so-called secure communication system, such that the digital signal (y) at output cannot be deduced from the digital signal (x) at input, consisting in dispatching the digital signal (x) to a device effecting a one-way function.The method includes the following steps:the digital signal (x) at the input is dispatched to a circuit C (1, 2) which gives as output a digital signal (x") of dimension n acceptable to the one-way function;the signal (x") from the circuit C (1, 2) is dispatched to the circuit effecting the one-way function giving as output the digital signal (y).The invention applies in particular to so-called secure communication systems.
    Type: Grant
    Filed: June 13, 1996
    Date of Patent: June 9, 1998
    Assignee: Thomson multimedia S.A.
    Inventors: Mario De Vito, Jacques Stern, Louis Gregoire, Jean-Bernard Fischer
  • Patent number: RE35829
    Abstract: A low cost spread spectrum modulator for BPSK, or Binary Phase Shift Keying capable of outputting the high modulation rate and suppressed carrier output needed in spread spectrum systems. The present invention provides high quality BPSK modulation without the double balance mixers as required in the prior art, thereby dispensing with the necessity of complex transistor/potonciometer or diode/transformer arrangements. The present invention provides BPSK modulation utilizing only one transformer, which can be adjusted for carrier suppression and two transistors. FET's, or digital logic gates or the like, allowing the present system to be driven from low power CMOS logic levels, yet producing eight db of gain. The present invention may also be utilized as a frequency multiplier, with the utilization of the appropriately high frequency transistor, FET, digital logic gate, or the like.
    Type: Grant
    Filed: November 17, 1995
    Date of Patent: June 23, 1998
    Assignee: Axonn Corporation
    Inventor: Hugh Britton Sanderford, Jr.