| 7003118 |
High performance IPSEC hardware accelerator for packet classification |
| Feb-21-2006 |
An architecture for a high performance IPSEC accelerator. The architecture includes components for scanning fields of packets, programming an IPSEC services device according to the scanned fields, and... |
| 6901514 |
Secure oblivious watermarking using key-dependent mapping functions |
| May-31-2005 |
A method for embedding a watermark into content is disclosed. The content contains content samples. The method including the steps of: receiving the content, creating a continuous watermark sequence from... |
| 6889324 |
Digital measurement apparatus and image measurement apparatus |
| May-3-2005 |
A digital measurement apparatus measures a physical measurement object, provides a digital signature of public-key cryptography to measured data of a thus-measured physical quantity, and manages the measured... |
| 6330335 |
Audio steganography |
| Dec-11-2001 |
An identification code signal is hidden in a carrier signal (such as an electronic data signal or a physical medium) in a manner that permits the identification signal later to be discerned. The carrier... |
| 6175627 |
Apparatus and method for embedding and extracting information in analog signals using distributed signal features |
| Jan-16-2001 |
Apparatus and methods are provided for embedding or embedding digital data into an analog host or cover signal. A distributed signal feature of the cover signal in a particular domain (time, frequency... |
| 5832057 |
Lockout device for preventing telephone eavesdropping from an extension device, and method |
| Nov-3-1998 |
Remote telephone coder 10R and local telephone coder 10L provide coding and decoding for voice communication between remote telephone set 11R and local telephone set 11L through telephone line 12. An eavesdropper... |
| 5613001 |
Digital signature verification technology for smart credit card and internet applications |
| Mar-18-1997 |
The presently used Asymmetric Digital Signature verification technologies, such as the system of RSA Data Security Corp., require complex mathematical operations for encryption and decryption. As a result,... |
| 5422919 |
EMI suppression coding |
| Jun-6-1995 |
EMI suppression technique that pseudorandomizes the positive or negative going transitions that are used to represent one binary state in a transmitted digital signal such as in MLT-3 data format. By pseudorandomizing... |
| 5319708 |
System for the simultaneous coding of a number of television signals and for decoding thereof in radiofrequency |
| Jun-7-1994 |
A system for the simultaneous coding of a number of television signals and for decoding thereof in radiofrequency. The radiofrequency TV signal or signals to be distributed undergo remodulation on at least... |
| 5283807 |
EMI suppression coding |
| Feb-1-1994 |
EMI suppression technique that pseudorandomizes the positive or negative going transitions that are used to represent one binary state in a transmitted digital signal such as in an MTL-3 data format. By... |
| 5165098 |
System for protecting digital equipment against remote access |
| Nov-17-1992 |
System for protection against remote access to digital equipment (1) emitting stray electromagnetic radiation (2) and operating with digital signals under clock control and being based on the representation... |
| 5029210 |
Cooperative communication system |
| Jul-2-1991 |
A cooperating communications system in which at least two stations and a connecting communications link form a cooperative communicating loop. Each station contains a plurality of amplification stages,... |
| 4932057 |
Parallel transmission to mask data radiation |
| Jun-5-1990 |
Aircraft often include a central memory which distributes data to a number of communication, navigational and other utilization devices. In order to achieve a high degree of security for data transmission... |
| 4737990 |
Unauthorized channel jamming signal applying method for CATV system |
| Apr-12-1988 |
In a jamming signal applying device connected between a cable and subscribers' terminal units in a CATV system, a signal for scrambling the video signal is produced in a time sharing mode, with the time... |
| 4644396 |
Gate circuit for central control of CATV system |
| Feb-17-1987 |
A gate circuit for use in switching an interference signal in a CATV system whereby the output impedance of the gate circuit is constant, independent of the switching state of the gate circuit. The inventive... |
| 4636852 |
Scrambling and descrambling of television signals for subscription TV |
| Jan-13-1987 |
A scrambled TV signal is provided by adding thereto a signal having an amplitude which changes pseudorandomly in successive increments of time, the duration of each of which is much less than the horizontal... |
| 4361729 |
Narrowband analog message privacy system |
| Nov-30-1982 |
A privacy system in which an analog information-bearing signal is linearly combined with a noiselike coding waveform to produce a composite waveform of unrecognizable, scrambled signal for transmission... |
| 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... |
| 4188580 |
Secure communication system |
| Feb-12-1980 |
A secure communication system for transmitting and receiving an encoded information signal. The system generates at transmitting and receiving locations a predetermined unique pseudorandom code. A synchronized... |
