| 6950518 |
Data encryption system |
| Sep-27-2005 |
A system (100) and method (400, 500) for data encryption and decryption are disclosed. The encryption system is operable at encryption rates in excess of 10 Mbps and is expandable to over 200... |
| 6919794 |
Circuit for controlling the random character of a random number generator |
| Jul-19-2005 |
A circuit for controlling the random character of a bit flow, including an input shift register receiving the bit flow and having its outputs exploited in parallel, at least one element for comparing at... |
| 6779111 |
Indirect public-key encryption |
| Aug-17-2004 |
A system and method for encrypting data communications between a client and server utilizes an untrusted proxy server to perform computationally expensive encryption calculations which would otherwise... |
| 5956401 |
In-service monitoring in communications networks |
| Sep-21-1999 |
A communications path not using a deterministic signal frame structure is provided with performance monitoring by using known Alarm Indication Signal (AIS) type monitoring on the path but scrambling traffic... |
| 5715312 |
Concealment method and arrangement and reproducing apparatus provided with the concealment arrangement |
| Feb-3-1998 |
Arrangement for carrying out a concealment on an information signal, the information signal including subsequent signal blocks (padding sequence), each signal block including a sequence of alternate first... |
| 5636279 |
Scramble apparatus and descramble apparatus |
| Jun-3-1997 |
A scramble apparatus for scrambling data including a variable length code and a descramble apparatus is for descrambling a scrambled signal, and a scramble transmission apparatus comprising the scramble... |
| 5617476 |
Audio scrambling system for scrambling and descrambling audio signals |
| Apr-1-1997 |
A scrambling system has a scrambling apparatus and a descrambling apparatus for scrambling and descrambling a digital audio signal having a plurality of 16-bit long sample data units. The scrambling apparatus... |
| 5515437 |
Scramble transmission apparatus and signal processing apparatus |
| May-7-1996 |
The occurrence of malfunction on the reproduction side is avoided by preventing a scrambled signal from being coincided with a reserved word in the signal when a scramble process is carried out in order... |
| 5333197 |
System to prevent a scrambler from generating undesired symbols |
| Jul-26-1994 |
A communication system is described in which data characters are each repeatedly encoded in an encoder (3) until an encoded character occurs which is not one of a predetermined set of characters, e.g.... |
| 5239581 |
Secret communication apparatus |
| Aug-24-1993 |
This secret communication apparatus used in an audio and data transmission system has scramble/descramble circuits formed of programmable logic means. A control circuit in the apparatus instructs the programmable... |
| 5086470 |
Scrambling in digital communications network using a scrambled synchronization signal |
| Feb-4-1992 |
A passive, all optical communications network is provided in which a single optical source in a central station serves many outstations (e.g. telephones in customers' premises). Time division multiplexed... |
| 4993070 |
Ciphertext to plaintext communications system and method |
| Feb-12-1991 |
A ciphertext to plaintext communications system including a communications channel, a generator, a data device, an encryptor, a black to red communicator (BRC) device, a decryptor, and a comparator. The... |
| 4864617 |
System and method for reducing deadlock conditions caused by repeated transmission of data sequences equivalent to those used for inter-device signalling |
| Sep-5-1989 |
A system and method for reducing the probability of deadlock conditions caused by the repeated transmission of data frames containing data sequences equivalent to those used by serial data communications... |
| 4792949 |
Service channel circuit for multiplexed telecommunications transmission systems |
| Dec-20-1988 |
In accordance with the present invention a plurality of input control data bits are added to a plurality of input telecommunications transmission channels in the form of an input control word wherein any... |
| 4675477 |
Electronic device providing automatic permutations of a Vigenere Square |
| Jun-23-1987 |
This invention relates to cryptographic teletypewriter systems and more picularly to an electronic device for use in such systems which automatically provides permutations of a Vigenere Square. |
| 4627074 |
Method and arrangement for transmitting characters |
| Dec-2-1986 |
In order to prevent bit combinations which are assigned to specific control characters from arising when ciphering characters, transmittable characters which consist of a part of the ciphered character... |
| 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... |
| 4369333 |
Method and apparatus for enciphering and deciphering of information |
| Jan-18-1983 |
Plain text or information which is to be processed at the transmitter end of the system is formed by groups of plain text or information signals which are separated by separation signals. In the absence... |
| 4329545 |
Circuit arrangement for the control of semi-duplex data transmission system |
| May-11-1982 |
In a circuit arrangement for the control of semi-duplex data transmission systems, which operate in accordance with crypto techniques, and in which the data of a data source are supplied to a data terminal... |
| 4323729 |
Circuit arrangement for the control of a crypto operation in the case of procedure-controlled semi-duplex data transmission systems |
| Apr-6-1982 |
A crypto control circuit arrangement is disclosed for controlling crypto operation in the case of procedure-controlled semi-duplex data transmission systems in which data are transmitted from a first station... |
| 4262359 |
Five V insertion unit |
| Apr-14-1981 |
2. For use with a cryptographic teletype transmission system having a relay for transferring teletype characters to an encyphering transmitter, a decyphering receiver and a teletype printer, a security... |
| 4208545 |
Secrecy system |
| Jun-17-1980 |
1. In a system of secret telegraph communication, an incoming channel over which miscellaneous matter intelligence signals are periodically received, an outgoing channel susceptible of operating at a higher... |
| 4172213 |
Byte stream selective encryption/decryption device |
| Oct-23-1979 |
An apparatus for insertion in a communications line for providing message secrecy within a significant portion of existing communications networks. At the transmitter end, the apparatus receives messages... |
