| 4760600 |
Cipher system |
| Jul-26-1988 |
In a cipher system used in transmission or storage of digital data, the encipherment section comprises a first modulo-2 adder for adding, bit by bit, the k-bit contents of a first shift register storing... |
| 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,... |
| 4663500 |
Cryptographic system |
| May-5-1987 |
A cryptographic system comprises a modulo-2 adder having a first input receptive of a sequence of binary digits to be scrambled and a second input receptive of a sequence of scrambling binary digits for... |
| 4661980 |
Intercept resistant data transmission system |
| Apr-28-1987 |
A secure communication system, which may be safely used even in the prese of an enemy interceptor, includes a transmitter and a receiver. The transmitter comprises a first modulo-2 adder, having as one... |
| 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... |
| 4447672 |
Device for encrypting each input data bit by at least one keying bit decided by a code pattern and a bit pattern of a predetermined number of preceding encrypted bits |
| May-8-1984 |
An encrypting device for an input data bit sequence comprises a shift register for producing a bit pattern represented by successive encrypted bits for the data bits preceding a current bit. A bit pattern... |
| 4408093 |
Cryptographic encoder-decoder |
| Oct-4-1983 |
An electronic cryptographic encoder-decoder is disclosed which performs the equivalent operations of a known simple hand-held cryptographic encoder-decoder. The electronic cryptographic encoder-decoder... |
| 4369434 |
Enciphering/deciphering system |
| Jan-18-1983 |
The enciphering section of an enciphering/deciphering system includes a random number generator, a primary code memory and a multiplex unit in addition to the actual enciphering unit. The deciphering section... |
| 4313031 |
Encipher-decipher device having semi-automatic generation of the code key during data entry |
| Jan-26-1982 |
An encipher-decipher apparatus including an input keyboard and a processing and control stage which enciphers or deciphers data received directly from the keyboard or preferably from a text store with... |
| 4255749 |
Apparatus for converting code signal to visual display |
| Mar-10-1981 |
Apparatus for converting a train of code signals representative of a letter, number, or symbol to a visual display of such corresponding letter, number, or symbol. The train of signals includes individual... |
| 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... |
| 4228321 |
Privacy transmission system with remote key control |
| Oct-14-1980 |
In the prior art key control signals are produced at a scrambling location, used at that location for scrambling and then transmitted along with the scrambled message to the unscrambling location. In accordance... |
| 4176247 |
Signal scrambler-unscrambler for binary coded transmission system |
| Nov-27-1979 |
A method and an apparatus for encoding and decoding a binary digital data signal is disclosed. An input signal that is to be encoded for transmission is shifted through a serial shift register with the... |
| 4107458 |
Cipher computer and cryptographic system |
| Aug-15-1978 |
A system for the protection of stored and transmitted data including a random access memory accessed by counters and used for encrypting and decrypting signals in a cryptographic system using stream and... |
| 4058673 |
Arrangement for ciphering and deciphering of information |
| Nov-15-1977 |
An arrangement for ciphering and deciphering comprises a number of cycle length counters. Each of the counters has a different cycle length and generates a series of bits by scanning associated memory... |
