| 5317639 |
Non-linear block substitution devices derived by constructive corruption |
| May-31-1994 |
Methods and apparatus for non-linearizing modulo 2 addition based encryption by block substitution techniques which allows use of the substitution scheme with relatively simple hardware and yet makes cryptanalysis... |
| 5231662 |
Method and device for enciphering data to be transferred and for deciphering the enciphered data, and a computer system comprising such a device |
| Jul-27-1993 |
Method and device for enciphering data words of a word width of n bits, in particular data words to be written in a computer storage, wherein a product cipher circuit comprises alternately one from a plurality... |
| 5226082 |
Variable length decoder |
| Jul-6-1993 |
Apparatus for decoding a stream containing codes of a variable length code (VLC) takes advantage of the fact that a trie representation of the VLC can be pruned to leaves that each represent a complete... |
| 5214704 |
Nonlinear dynamic substitution devices and methods for block substitutions |
| May-25-1993 |
Methods and apparatus for nonlinearizing modulo 2 addition based encryption by block substitution techniques which allows use of the substitution scheme with relatively simple hardware and yet makes cryptanalysis... |
| 5214703 |
Device for the conversion of a digital block and use of same |
| May-25-1993 |
The device (12) comprises nine encryption stages (61.1, 61.2, 69), the first eight of which are constructed identically. It further comprises a key subblock generation unit (63), an input unit (21), and... |
| 5214701 |
Method of processing data by compression and permutation for microcircuit cards |
| May-25-1993 |
This method of processing data protected by a coding is particularly suitable to be used in microcircuit cards utilizing the method of processing data of the DES type. In the DES method, a step SP of transformation... |
| 5168521 |
Method of executing an irregular permutation of data protected by encryption |
| Dec-1-1992 |
This method of processing data protected by encryption is particularly suitable for smart cards utilizing the DES system. The method enables the execution of the irregular permutation of the key on the... |
| 5161191 |
Encryption system for time division multiplexed networks |
| Nov-3-1992 |
An encryption system is provided for interfacing a time division multiplexing (TDM) telecommunications arrangement with an encryption device for the scrambling of data received by the telecommunications... |
| 5121429 |
Digital signal processing |
| Jun-9-1992 |
For more convenient mechanisation, the modulo m reduction of a binary number P can be carried out by conditionally summing the modulo m reductions of a power series of two and then modulo m reducing the... |
| 5091940 |
Data router with burst shuffling and deshuffling output buffers |
| Feb-25-1992 |
An improved data router 10 with burst deshuffling and shuffling output buffers that performs input data deshuffling and output data formatting and shuffling using only one burst buffer per input channel... |
| 5058163 |
Interface unit for transferring digital data between time-domain multiplexed communication links |
| Oct-15-1991 |
An apparatus for transferring digital data between time-domain multiplexed communication links of a telephone system which forms part of a computer network. A time-domain multiplexed communication link... |
| 5054068 |
Trunked radio communication system having encrypted system control information |
| Oct-1-1991 |
A trunked communication system having a control resource that encrypts system control messages. In one embodiment, the encryption includes controlling a bit interleaving process (208, 311) as a function... |
| 5054067 |
Block-cipher cryptographic device based upon a pseudorandom nonlinear sequence generator |
| Oct-1-1991 |
A block-cipher cryptographic device that processes plaintext/encrypted input data with a key signal to provide encrypted/decrypoted output data. Such device includes a shift register for receiving input... |
| 5038376 |
Block substitution based encryption by a modulo 2 addition method and apparatus |
| Aug-6-1991 |
Methods and apparatus for modulo 2 addition based encryption by block substitution techniques which allows use of the substitution scheme with relatively simple hardware. The block substitution, a one... |
| 5014313 |
Text modifier |
| May-7-1991 |
A method is disclosed and apparatus is described whereby plain text is modified before it is input to a binary key generator (encryptor). According to the invention, a plain text bit may be modified by... |
| 5008935 |
Efficient method for encrypting superblocks of data |
| Apr-16-1991 |
This invention relates to an arrangement for encrypting data for storage in a computer and/or for transmission to another data processing system. The plain text data is divided into buffers and the buffers... |
| 5003596 |
Method of cryptographically transforming electronic digital data from one form to another |
| Mar-26-1991 |
A cryptographic system creates a key table from a single key such that the relationship between the keys in the key table cannot be determined even if the system implementation is known. The system uses... |
| 5003597 |
Method and apparatus for data encryption |
| Mar-26-1991 |
A method and apparatus for encrypting and decrypting data which operates efficiently on computers of differing architectures is disclosed. Unlike previous encryption/decryption method and apparatus, the... |
| 5001755 |
Security system network |
| Mar-19-1991 |
The present invention uniquely applies data communications network techniques to a security system. A series of slave transponders are coupled via a full duplex bus to a master node. The master node is... |
| 4969190 |
Encrypting system of data |
| Nov-6-1990 |
A data encrypting system according to the CBC system involves a limitation in a range of a numerical value which expresses data (smaller than a predetermined integer N). The encrypting system has an encrypting... |
| 4965827 |
Authenticator |
| Oct-23-1990 |
An authenticator for digital data is derived by generating a numerical array, using a secret key to controllably shift the relative positions of the elements of the array, and applying the scrambled array... |
| 4964164 |
RSA computation method for efficient batch processing |
| Oct-16-1990 |
A computation for batch processing public key encryption method using a processor. The method batch processes an e1.sup.th root of a first message-data signal, M1, as M1.sup.1/e1, and an e2.sup.th root... |
| 4907275 |
Encryption apparatus |
| Mar-6-1990 |
In an encryption apparatus, prior to encryption process, information indicating whether plain text blocks are to be encrypted or not is stored in a mask register, and the number of blocks of the plain... |
| 4866772 |
Communication system |
| Sep-12-1989 |
In a communication system such as the videotext system, the data are prepared according to the so-called ISO layer model before such data are transmitted via a conventional telephone circuit. The fact... |
| 4850019 |
Data randomization equipment |
| Jul-18-1989 |
Input data is split by a splitting part into a plurality of block data having an equal data length to be processed through respective channels. Each channel data is subjected in a function operation part... |
| 4815130 |
Stream cipher system with feedback |
| Mar-21-1989 |
A cipher system in which a key is initially inserted into a shift register and the serial output of the shift register is added to the plain text message and the sum is fed back into the serial input of... |
| 4803725 |
Cryptographic system using interchangeable key blocks and selectable key fragments |
| Feb-7-1989 |
A cryptographic system is used for the secure transmission of digitized signals to a plurality of receivers. At the transmission end, a key consisting of two blocks, each including a plurality of key fragments,... |
| 4776011 |
Recursive key schedule cryptographic system |
| Oct-4-1988 |
An encryption system in which a code word is processed, byte by byte, by a Vernan type process followed by non-linear encryption techniques, all of which are repeated several times, to generate a working... |
| 4751733 |
Substitution permutation enciphering device |
| Jun-14-1988 |
A substitution-permutation enciphering device. This device, adapted for transforming a binary word into another binary word, by a succession of substitutions and permutations, under the control of a key,... |
| 4742544 |
Television transmission network with scrambling and descrambling |
| May-3-1988 |
A controlled access television communications network in which scrambling and descrambling are accomplished by digital signal processing. At the scrambler, the video and audio information are digitized,... |
| 4727579 |
Scrambled television signals |
| Feb-23-1988 |
A television receiver for receiving scrambled television signals has an arrangement (3) which provides scrambled video components (V) and packet arranged sound/data components (D) some of which are also... |
| 4723246 |
Integrated scrambler-encoder using PN sequence generator |
| Feb-2-1988 |
Simplified method and apparatus for performing integrated scrambling and encoding or descrambling and decoding of block code digital transmissions is disclosed. The method involves setting the scrambling... |
| 4668103 |
Polygraphic encryption-decryption communications system |
| May-26-1987 |
A public-key system for encoding, or encrypting, digital data wherein at least two singular matrices of binary bits provide separate encrypting factors. Each matrix is a product of a common singular matrix... |
| 4636851 |
Signal coding for secure transmission |
| Jan-13-1987 |
A multiplexed analogue component (MAC) television signal is encrypted for transmission and reception by authorized recipients only by dividing the signal into blocks and reordering the blocks prior to... |
| 4606042 |
Method for digital transmission of messages |
| Aug-12-1986 |
The invention involves a method for digital transmission of messages in a digital radio relay system which utilizes a superframe so additional information can be transmitted with a digital signal. This... |
| 4602283 |
System for spatially and temporally transposing data words arrayed in periodically recurring patterns |
| Jul-22-1986 |
A train of incoming data words, specifically digitized video samples arrayed in frames of Y lines of X pixels each which have already undergone a 2-dimensional spatial transformation, is scrambled by being... |
| 4591660 |
Common control audio decryptor |
| May-27-1986 |
Decryption of a plurality of simultaneously received, randomly phased signals is realized by employing a single data encryption standard module in a time shared manner. A plurality of process state counters,... |
| 4575754 |
Video scrambler system |
| Mar-11-1986 |
A video signal is scrambled by partitioning the signal into blocks of segments, reversing the sequence of segments in each block, randomly delaying the reversed segments and reversing the sequence of the... |
| 4520232 |
Polygraphic encryption-decryption system |
| May-28-1985 |
A system for encoding, or encrypting, digital data wherein an invertible matrix of binary bits provides the encrypting factor or key, this invertible matrix being loaded in a memory. Blocks or sets of... |
| 4401854 |
Simultaneous transmission of an analog message signal and a digital data signal |
| Aug-30-1983 |
In its most general form, the present invention may be employed to simultaneously transmit information, either digital or analog, from two separate and distinct sources, denoted A and B, where the information... |
| 4326098 |
High security system for electronic signature verification |
| Apr-20-1982 |
The system provides both electronic signature and message verification with a minimum of excess coding information on an instantaneous basis and is easily restartable in a store and forward environment.... |
| 4322577 |
Cryptosystem |
| Mar-30-1982 |
Encryption and decryption of information of a message is performed by partitioning a plaintext message into blocks of binary digits and by further partitioning said blocks into subblocks which are interpreted... |
| 4319079 |
Crypto microprocessor using block cipher |
| Mar-9-1982 |
A cryptographic microprocessor for processing data and executing programs which are stored in enciphered blocks to prevent unauthorized alteration and copying. Such a "crypto-microprocessor" deciphers... |
| 4316055 |
Stream/block cipher crytographic system |
| Feb-16-1982 |
The system disclosed comprises a dual function cryptographic system capable of operating in either a stream or block cipher mode. Further, with minimal alteration the system is capable of performing either... |
| 4302810 |
Method and apparatus for secure message transmission for use in electronic funds transfer systems |
| Nov-24-1981 |
An electronic funds transfer system wherein it is required that a bank be reasonably guaranteed that the two parties to a retail transaction (i.e., a person and a retailer) agree on the transaction before... |
| 4275265 |
Complete substitution permutation enciphering and deciphering circuit |
| Jun-23-1981 |
A complete substitution permutation enciphering and deciphering circuit and method for transforming a plaintext signal into an enciphered signal which is secure during transmission. After receipt, the... |
| 4264782 |
Method and apparatus for transaction and identity verification |
| Apr-28-1981 |
A method and apparatus whereby the senders and receivers of messages sent over a transmission system including a Host CPU may guarantee the integrity of the data content of the message and also the absolute... |
| 4255811 |
Key controlled block cipher cryptographic system |
| Mar-10-1981 |
A cryptographic system for encrypting a block of binary data under the control of a key consisting of a set of binary symbols. The cryptographic system may be utilized within a data processing environment... |
| 4249180 |
Past dependent microcomputer cipher apparatus |
| Feb-3-1981 |
Apparatus for use in a secure data communication system includes a microcomputer that controls a cipher process by which sensitive data is encrypted before transmission. When activated, the apparatus accepts... |
| 4229818 |
Method and apparatus for enciphering blocks which succeed short blocks in a key-controlled block-cipher cryptographic system |
| Oct-21-1980 |
A method and apparatus for providing improved error-recovery and cryptographic strength when enciphering blocks which succeed short blocks in a Key-Controlled Block-Cipher Cryptographic System with chaining.... |
