| 7023992 |
Data multiplexing device, program distribution system, program transmission system, pay broadcast system, program transmission method, conditional access system, and data reception device |
| Apr-4-2006 |
In a data multiplexing device which multiplexes and transmits the transport stream packets of program data consisting of a plurality of data elements constructed in the form of transport stream packets,... |
| 7006634 |
Hardware-based encryption/decryption employing dual ported key storage |
| Feb-28-2006 |
A system for the encryption and decryption of data employing dual ported RAM for key storage to accelerate data processing operations. The on-chip key storage includes a dual-ported memory device which... |
| 7003114 |
Method and apparatus for achieving crypto-synchronization in a packet data communication system |
| Feb-21-2006 |
A method and apparatus for achieving crypto-syncronization in a packet data communication system employing cryptographic communications. In a transmitter, a state vector is incremented at a predetermined... |
| 6983022 |
Method and apparatus for modulating and demodulating data into a variable-length code and providing a sync signal to the train of codes |
| Jan-3-2006 |
A data-modulating apparatus for modulating data having a basic data length of m bits, to a variable-length code(d, k; m, n: r) having a basic code length of n bits. A sync signal is added to a recieved... |
| 6952480 |
Self-synchronous data scrambler |
| Oct-4-2005 |
An encryption system has been provided to self-synchronously scramble communications where the receiver must recover the clock information from the data stream, such as the SONET format. To prevent jamming... |
| 6925183 |
Preventing shortened lifetimes of security keys in a wireless communications security system |
| Aug-2-2005 |
23A wireless communications device has a first security key, a second security key, and established channels. Each established channel has a corresponding security count value, and utilizes a security... |
| 6920557 |
System and method for wireless user interface for business machines |
| Jul-19-2005 |
A method and system for providing external user interfaces is described. In one configuration a co-located external processor and a business machine negotiate a communications connection. The co-located... |
| 6879637 |
Method and apparatus for modulating and demodulating data into a variable length code and a providing medium for implementing the method |
| Apr-12-2005 |
A method and apparatus for modulating data modulates data having a length of m-bits to a variable length code having a basic code length of n-bits. A SYNC but insertion section adds a sync signal to a... |
| 6873707 |
Hardware-based encryption/decryption employing cycle stealing |
| Mar-29-2005 |
A system for the encryption and decryption of data employing cycle stealing to accelerate data processing operations. The cycle stealing is employed by using level sensitive latches in a microcode controller... |
| 6778670 |
Method and apparatus for encryption and decryption |
| Aug-17-2004 |
A method and apparatus are provided for encrypting a stream of data transmitted within a frame. The method includes determining a first initialization state in a first preselected interval, and determining... |
| 6654885 |
Method for authorization checking and configuration for carrying out the method |
| Nov-25-2003 |
The system checks whether authorization exists for at least two data processing devices to exchange data with one another. In the preferred embodiment, both data processing devices are of identical design.... |
| 6560338 |
Limiting delays associated with the generation of encryption stream ciphers |
| May-6-2003 |
A method and an apparatus for generating encryption stream ciphers are based on a recurrence relation designed to operate over finite fields larger than GF(2). A non-linear output can be obtained by using... |
| 6408077 |
Descrambling device of a security element and security element comprising such a device |
| Jun-18-2002 |
In a device for descrambling scrambled digital data, the digital data are grouped into parallel combinations of bits before being descrambled. The combinations of bits are descrambled and then split back... |
| 6385319 |
Encoding circuit and method of detecting block code boundary and establishing synchronization between scrambler and descrambler |
| May-7-2002 |
The present invention comprises the bus reset detection circuit 6 detecting a bus reset signal from the network initiation/control state machine, the bus reset identification code generation circuit 8... |
| 6215876 |
Apparatus for and method of detecting initialization vector errors and maintaining cryptographic synchronization without substantial increase in overhead |
| Apr-10-2001 |
An apparatus and method for detecting erroneous initialization vectors transmitted over a communications channel and maintaining cryptographic synchronization by comparing a received vector with a predicted... |
| 6005940 |
System for securely storing and reading encrypted data on a data medium using a transponder |
| Dec-21-1999 |
A self contained data medium is provided with an apparatus for generating a decrypting key for decrypting stored data. Frames of encrypted data are stored on the data medium such as a video or audio disk.... |
| 5987139 |
Method for encryption of information |
| Nov-16-1999 |
The method involves modifying an encryption key (Kc) in accordance with a given algorithm and in dependence on the ordinal number of a time slot to obtain a modified encryption key. A modified pseudo-random... |
| 5987137 |
Method for the encryption of data transfer |
| Nov-16-1999 |
The object of the invention is a method for the encryption of information transferred between data transfer devices (MS, SGSN) in a data communication system wherein one or more data frames are created... |
| 5966450 |
Variable mask for encryption generated independently at communications stations |
| Oct-12-1999 |
Frames of data are encrypted by combining each of the frames with a mask that varies from frame to frame. The mask is obtained by using a frame counter as the seed for a pseudo random number generator,... |
| 5881154 |
Data scramble transmission system |
| Mar-9-1999 |
A data scramble transmission system with a data transmission link coupled between sending and receiving ends is provided. The link adopts transmission frames each of which is constituted by data and control... |
| 5838797 |
Secure communication by encryption/decryption of vector at PSK modulation/detection stage |
| Nov-17-1998 |
At the transmit end of a secure communication system, an input data symbol is mapped to a corresponding vector in a two-dimensional phase plane. The vector is pseudorandomly phase-rotated in a first direction... |
| 5784462 |
Digital signal receiver capable of receiving data encrypted and transmitted in online processing |
| Jul-21-1998 |
In a decoding processing circuit of a digital signal receiver, a first comparison circuit detects that a prefix of packet data is inputted in a shift register on the basis of a count value of a counter... |
| 5778075 |
Methods and systems for mobile terminal assisted handover in an private radio communications network |
| Jul-7-1998 |
Mobile assisted handover of an encrypted traffic connection between linked base stations of a private radio communications network are provided in a system including a plurality of base stations and a... |
| 5727064 |
Cryptographic system for wireless communications |
| Mar-10-1998 |
A wireless communications system (110) with increased privacy. The system (110) transmits an encrypted signal between a base station (112) and a wireless terminal (122). In the forward channel, the base... |
| 5717762 |
WACS-type mobile communication with a unified frame format |
| Feb-10-1998 |
In a mobile communication system of the WACS type, frame formats are unified for DSL, HDSL, and DS1 channels. In addition, each novel base station (25) comprises a radio frame number processor for adding,... |
| 5717761 |
Data transmission system capable of carrying out a data transmission with a high security |
| Feb-10-1998 |
A transmission section is responsive to first through K-th data signals to transmit a transmission signal through a transmission path to a reception section. The transmission signal has first through K-th... |
| 5710815 |
Encoder apparatus and decoder apparatus for a television signal having embedded viewer access control data |
| Jan-20-1998 |
An encoding apparatus and an associated decoding apparatus for a television signal having embedded viewer access control data. A program category code is inserted into a television signal by the encoding... |
| 5689568 |
Medium access control for a mobile satellite system |
| Nov-18-1997 |
The present invention provides a medium access control (MAC) layer in a mobile satellite system. The MAC transfers data across the physical channels in the air interface between the mobile terminals, the... |
| 5652796 |
Data encryption control system |
| Jul-29-1997 |
The data encryption system includes a first stage and a second stage data encryption engine in combination with a micro control system. The data encryption system is responsive to control signals from... |
| 5592554 |
Method for data security in a digital telecommunication system |
| Jan-7-1997 |
For data security in a digital telecommunication system having a plurality of subscriber equipment, a public key is respectively calculated from a secret key prescribed in a first subscriber equipment.... |
| 5559890 |
Crypto equipment |
| Sep-24-1996 |
For the transmission of information, such as voice and data that it is necessary to keep secret, it is standard to encode the information at the transmitting side in the digital level and to in turn decode... |
| 5511124 |
Cryptographic equipment |
| Apr-23-1996 |
In the transmission of information which require secrecy, such as voice and data, serial bit streams having bit rates of more than 100 Mbit can occur, particularly given digital signal hierarchies according... |
| 5488663 |
Encoding methods for generating a digital signal containing modulated bit allocation information, and record carriers containing that signal |
| Jan-30-1996 |
Transmission system for transmitting and receiving, and subband encoding methods for generating for transmission, digital signals containing modulated bit allocation information; and record carriers containing... |
| 5488659 |
Encryption/decryption process and apparatus for a multichannel television system |
| Jan-30-1996 |
An encryption/decryption system which facilitates simultaneous decryption of multiple encrypted television signals thus making them simultaneously available for direct tuning in television receivers. The... |
| 5375171 |
Transmission system, and transmitter and receiver used in the transmission system for transmitting and receiving digital signals containing modulated bit allocation information |
| Dec-20-1994 |
Transmission system, and transmitter and receiver for use in the transmission system for transmitting and receiving digital signals containing modulated bit allocation information. The transmitter encodes... |
| 5361302 |
Method for encryption sync compression in an encrypted radio telephone interconnect system |
| Nov-1-1994 |
A method for transparently coupling an encrypted two-way RF communication unit (100) with an encrypted landline communication unit (104). An RF message comprised of a plurality of data frames (401,402,... |
| 5321754 |
Sequence synchronization |
| Jun-14-1994 |
A data sequence is transmitted from a transmitter to a receiver, being scrambled at the transmitter by adding a pseudo random sequence (PRS) thereto. At the receiver the received data is unscrambled by... |
| 5319707 |
System and method for multiplexing a plurality of digital program services for transmission to remote locations |
| Jun-7-1994 |
A system and method for multiplexing a plurality of digital programs for transmission to a plurality of remote locations is claimed. An encoder is provided that first generates a plurality of subframe... |
| 5297208 |
Secure file transfer system and method |
| Mar-22-1994 |
This invention is a system and method for securely and robustly transferring a file from one computer to another without having a prearranged encryption key. Data is transferred by first generating some... |
| 5293423 |
Synchronizing method in a mobile radio system |
| Mar-8-1994 |
A synchronizing method in a mobile radio system which operates with Time Division Multiple Access (TDMA) but which lacks global time reference for all base stations and mobiles in the system. The inventive... |
| 5245661 |
Distributed sample scrambling system |
| Sep-14-1993 |
A distributed sample scrambling system comprising scrambler and a descrambler. The scrambler includes a first shift register generator (SRG) 2 for generating scrambler SRG sequence, an exclusive OR gate... |
| 5235645 |
Scrambler/descrambler system for data transmission |
| Aug-10-1993 |
A scrambler system is provided for the detection and separation of synchronization signals from data signals, and for the scrambling of the data signals such that no long and repeatable series of one's... |
| 5224161 |
Method of scrambling and of unscrambling composite video signals, and device for implementation |
| Jun-29-1993 |
In order to scramble as effectively as possible pay-television transmissions, the transmitter is made to transmit, at one and the same time, access messages and entitlement messages, all of them crypted... |
| 5185799 |
Parallel scrambler used in SONET data transmission |
| Feb-9-1993 |
A data scrambler circuit which adds the SONET polynomial 1+X.sup.6 +X.sup.7 to data in a parallel format to thereby reduce circuitry clock rates to one-eighth the line rate, which reduces power consumption... |
| 5175767 |
In-band framing method and apparatus |
| Dec-29-1992 |
An in-band framing encoder having a data input and a data output, for continuously operating a CPE-framed-data signal having CPE-framing data and payload data. The CPE-framed-data signal includes a plurality... |
| 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... |
| 5148482 |
Layered session data unit frame |
| Sep-15-1992 |
A layered session data unit frame (300) is provided wherein a first frame (200), designated a session data unit("SDU"), containing user information (209), a link control field (205) and an encryption field... |
| 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... |
| 5077794 |
Dual framing bit sequence alignment apparatus and method |
| Dec-31-1991 |
A dual-framing-bit-alignment apparatus having a communications channel, a data device, an encryptor, a framing-bit device, a decryptor, a first framing-bit repositioner, and a second framing-bit repositioner.... |
| 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... |
