Abstract: A system and method for generating analog-digital mixed chaotic signal and an encryption communication method thereof are provided. In the system and method, the complementarity between continuous chaotic systems (12, 22) and digital chaotic systems (11, 21) are reasonably utilized. In specific, the digital chaotic systems, which are separated from each other, control the local continuous chaotic systems respectively, so as to enable the continuous chaotic systems, which are also separated from each other, to stably and synchronously work for a long time. Thus, there is no need to transmit the synchronizing signal, and as a result the anti-attack capability is increased effectively. Further, the continuous chaotic systems disturb the local digital chaotic systems to prevent the digital chaotic systems from degradation. This compensates the drawbacks of digital chaotic systems.

Abstract: The present invention provides a method and apparatus for random number generation using a scattering waveguide. The apparatus includes a light source for providing coherent light and a scattering waveguide for receiving the coherent light and providing scattered light. The relative position of the light source and the scattering waveguide are variable. The apparatus also includes a detector for forming at least one random number based on the scattered light.

Abstract: The invention relates to a data carrier having a semiconductor chip (5) with at least one memory. The memory contains an operating program that is able to perform at least one operation (h). In order to prevent unauthorized access to the data (x) processed with the operation (h), both said data and the operation (h) itself are disguised. The disguising of the data (x) and the operation (h) is coordinated such that the disguised operation (hR1R, hR1R2) generates either the output data (y) of the undisguised operation (h) or disguised output data (y{circle around (x)}R2) from which the output data (y) can be determined.

Abstract: A digital communication system based on the use of chaotic carriers is disclosed. For each symbol to be sent, the transmitter sends a reference chaotic signal followed by a transformed version of the reference chaotic signal. For different symbols, different transformations are performed. Also, the transformations are designed such that the transformed versions of the reference chaotic signal do not resemble the original reference chaotic signal. As a consequence, little information can be deduced by inspecting the frequency spectrum of the transmitted signal. Moreover, even if the communication could be detected, it is difficult to decode the messages because there are numerous transformations possible.

Abstract: A one-way stabilized QKD system (10) that utilizes a control signal (CS) and a quantum signal (QS) that travel the same path through the system from a first QKD station (Alice) to a second QKD station (Bob). The control signal is detected at Bob and used to stabilize Bob's side of the interferometer against phase variations. The system also includes a polarization control stage (200) that controls (e.g., scrambles) the polarization of the photons entering Bob. The combination of the polarization control and the active phase stabilization of the interferometer at Bob's end allows for the stable operation of the interferometer when used as part of a one-way QKD system.

Abstract: A chaos generator for accumulating stream entropy is disclosed. The chaos generator includes a random source coupled to an entropy accumulator that is configurable for generating a binary random input sequence. The entropy accumulator is configurable for accumulating entropy of the input sequence and providing a binary random output sequence based on the accumulated entropy. The binary random output sequence is reduced by a modular reduction operation having a modulus that is set equal to a cryptographic prime (e.g., the order of an elliptic curve). The number of iterations performed by the entropy accumulator on the binary random input sequence is selected to provide a binary random output sequence having a desired cryptographic strength. The chaos generator can be part of a signing and verification system that uses fast elliptic encryption for small devices.

Abstract: A cryptographic system (CS) is provided. The CS (500) is comprised of a data stream receiving device (DSRD), a chaotic sequence generator (CSG) and an encryptor. The DSRD (602) is configured to receive an input data stream. The CSG (300) includes a computing means (3020, . . . , 302N-1) and a mapping means (304). The computing means is configured to use RNS arithmetic operations to respectively determine solutions for polynomial equations. The solutions are iteratively computed and expressed as RNS residue values. The mapping means is configured to determine a series of digits in the weighted number system based on the RNS residue values. The encryptor is coupled to the DSRD and CSG. The encryptor is configured to generate a modified data stream by incorporating or combining the series of digits with the input data stream.

Abstract: An apparatus (1) and method for decoupling error correction from privacy amplification in a quantum key distribution (QKD 100) system includes two or more computer systems (102, 108) linked by quantum and classical channels (120, 122) where each computer system determines a generalized error syndrome associated with quantum communication between the systems, encrypts the generalized error syndrome using a sequence of values, and communicates the encrypted generalized error syndrome via a classical channel (128) to the other system, which uses the encrypted generalized error syndromes to compute error correction for the quantum transmission.

Abstract: A method includes receiving an authentication request from a mobile station (401) and determining whether to forward the request to an authentication agent. When it is determined to forward the request, the request is forwarded to the authentication agent (107). A random number and a random seed are received from the authentication agent (107). The random number and the random seed are forwarded to the mobile station (401). A response to the random number and the random seed from the mobile station (401) is received and forwarded to the authentication agent (107). The authentication agent (107) compares the response with an expected response. When the authentication agent (107) authenticates the mobile station (401), a derived cipher key is received from the authentication agent (107).

Abstract: A protection key for hardware includes a first storage area configured to store a key data used for permission to use software installed in a information processor, a second storage area configured to store a data table including a plurality of random numbers, a receiver configured to receive a cryptography key from the information processor, a coder/decoder configured to encrypt the key data based on the cryptography key by picking one random number from the data table, and a transmitter configured to transmit the encrypted key data to the information processor.

Abstract: There is provided a quantum-key distribution method between a plurality of users or groups. A center prepares a predetermined number of entangled states consisting of qubits equal to the number of the users, and generates quantum states consisting of the qubits belonging to each of the entangled states and corresponding to each of the users. The center transmits each of the quantum states to each of the users after an authentication process. Each of the users receiving the quantum state makes public an axis used to measure each of the qubits constituting the quantum states. The number of users in each group measuring the qubits with a predetermined axis is represented by module 4. If the sum of the module 4 of each group is even, each group collects the qubit measurement results of the users and acquires each group key. Therefore, it is possible to provide a high-security quantum-key distribution method between an unspecified number of users or groups.

Abstract: A quantum communication system including (a) an emitter configured to emit a plurality of photon pulses in groups of photon pulses, each group of photon pulses emitted over a group time period, wherein the average number of photons per pulse is less than 1, and (b) a detector including a gating mechanism configured to switch the detector between an on state and an off state. The detector is in an on state for at least the duration of two photon pulses during the group time period.

Abstract: A single-photon generator includes an exciton generation part including therein a quantum dot, an excitation part for generating an exciton in the exciton generator part, a recombination control part for controlling recombination timing of the exciton in the exciton generation part, and an optical window provided in the exciton generation part so as to pass a single photon formed as a result of recombination of the exciton, wherein the recombination control part causes, in the exciton generation part, recombination of the excitons at longer intervals than a recombination lifetime of a exciton molecule.

Abstract: A method is provided for coherently demodulating a chaotic sequence spread spectrum signal at a receiver (104). The method includes receiving a chaotic sequence spread spectrum signal including a plurality of information symbols. The method also includes generating a first string of discrete time chaotic samples. The first string of discrete time chaotic samples is identical to a second string of discrete time chaotic samples generated at a transmitter. The method further includes processing the chaotic sequence spread spectrum signal at the receiver to identify a time offset and a frequency offset relative to the first string of discrete time chaotic samples. Each of the discrete time chaotic samples of the first string of discrete time chaotic samples has a shorter sample time interval than the duration of the information symbols.

Abstract: A data-processing arrangement (3) comprises a data-handling circuit (4) and a supply-current circuit (8) whose dynamic behavior is inherently chaotic in the sense of Lyapunov. The data-processing arrangement is arranged so that a power supply current (io) consumed by the data-handling circuit flows through the supply-current circuit.

Abstract: A method is provided for generating a coherent chaotic sequence spread spectrum communications system. The method includes phase modulating a carrier with information symbols. The method also includes generating a string of discrete time chaotic samples. The method further includes modulating the carrier in a chaotic manner using the string of discrete time chaotic samples. Each of the discrete time chaotic samples has a shorter sample time interval than the duration of the information symbols. The generating step includes selecting a plurality of polynomial equations. The generating step also includes using residue number system (RNS) arithmetic operations to respectively determine solutions for the polynomial equations. The solutions are iteratively computed and expressed as RNS residue values. The generating step further includes determining a series of digits in the weighted number system based on the RNS residue values.

Abstract: A cascaded modulator system (20) and method for a QKD system (10) is disclosed. The modulator system includes to modulators (M1 and M2) optically coupled in series. A parallel shift register (50) generates two-bit (i.e., binary) voltages (L1, L2). These voltage levels are adjusted by respective voltage adjusters (30-1 and 30-2) to generate weighted voltages (V1, V2) that drive the respective modulators. An electronic delay element (40) that matches the optical delay between modulators provides for modulator timing (gating). The net modulation (MNET) imparted to an optical signal (60) is the sum of the modulations imparted by the modulators. The modulator system provides four possible net modulations based only on binary voltage signals. This makes for faster and more efficient modulation in QKD systems and related optical systems when compared to using quad-level voltage signals to drive a single modulator.

Abstract: A method and apparatus that uses tha dynamics of chaotic system for the remote generation of a digital key, for use in any encryption algorithm. After initialization, the dynamics of a chaotic system are allowed to generate the 0 and 1 bits of a key bistream. An initialization bistream is transmitted, using conventional transmission technologies, to an identical chaotic system. This chaotic system is driven into synchrony and allow to generate a key bitsream, which is identical to the other bitstream because the chaotic systems have been sychronized.

Abstract: An alternative design is given for an optimized quantum cryptographic entangling probe for attacking the BB84 protocol of quantum key distribution. The initial state of the probe has a simpler analytical dependence on the set error rate to be induced by the probe than in the earlier design. The new device yields maximum information to the probe for a full range of induced error rates. As in the earlier design, the probe contains a single CNOT gate which produces the optimum entanglement between the BB84 signal states and the correlated probe states.

Abstract: Provided is a range measurement apparatus and method based on chaotic ultra wideband (UWB) wireless communication. The apparatus includes a chaotic signal generating/modulating unit for generating/modulating chaotic signals and outputting them to a transceiving unit; a transceiver for transceiving radio signals; a detector for detecting the radio signals in forms of voltage signals; a transformer for sampling the analog voltage signals and outputting first digital signals of a predetermined level; a comparator for comparing levels of the analog voltage signals with a threshold value and outputting second digital signals; and a range measurement unit for calculating a leading edge, which is a moment when initial data of a packet payload arrive, by using the binary signals from transformation of the first digital signals based on the threshold and the second digital signals, and performing range measurement based on the leading edge. This research is applied to chaotic UWB wireless communication.

Abstract: A method includes receiving an authentication request from a mobile station (401) and determining whether to forward the request to an authentication agent. When it is determined to forward the request, the request is forwarded to the authentication agent (107). A random number and a random seed are received from the authentication agent (107). The random number and the random seed are forwarded to the mobile station (401). A response to the random number and the random seed from the mobile station (401) is received and forwarded to the authentication agent (107). The authentication agent (107) compares the response with an expected response. When the authentication agent (107) authenticates the mobile station (401), a derived cipher key is received from the authentication agent (107).

Abstract: A method of performing a cryptographic operation on a point in an elliptic curve cryptosystem using an elliptic carve. The method comprises the steps of obtaining information that uniquely identifies the elliptic curve and performing computations on the point to obtain the result of the cryptographic operation. The computations use the information. The computations produce an incorrect result if the point is not on the elliptic curve.

Abstract: Systems and methods for signal analysis using orbits of a chaotic system are provided. For example, a multiresolution analysis may be constructed and cupolets may be used to approximate arbitrary signals and compress images. Cupolets may be phase transformed to produce compact cupolets that are well-suited for producing sharp changes in signals, or to produce compact cupolets that are more oscillatory and have less or no sharp global maximum amplitudes. Alternatively, cupolets may be phase transformed to allow for optimal or near optimal adjustment to fit a signal.

Abstract: The encryption device includes a random number generator for generating a random number; and a first selector for selecting one of q fixed values in response to the random number, a second selector for selecting one set of q sets of fixed S-box tables in response to the random number. An XOR XORs an input with an XOR of a key with the fixed value. A nonlinear transform transforms an input nonlinearly in accordance with the selected set of fixed S-box tables. Another encryption device includes a plurality of encrypting units coupled in parallel, and a selector for selecting one of the plurality of encrypting units in response to the random number. The masking with the fixed values improves the processing speed and reduces the required RAM area.

Abstract: Given a set of elliptic curve points defined over a field F(p) and represented in projective coordinate, a method is presented which allows the embedding of data bits in both the X-coordinate and the Z-coordinate of the elliptic curve point when represented in projective coordinate. This makes the number of points that satisfy an elliptic curve equation and which can be used in the corresponding cryptosystem proportional to p2 rather than p. This can be used to either increase security by making the bit positions where data bits are embedded known only to the sender and receiver. Alternatively, it can be used to increase the number of data bits that can be encrypted per single elliptic curve point encryption. In another alternative, it can also be used to reduce p. Also, it can be used as a countermeasure by randomizing the bit positions where data bits are embedded. A similar formulation can be developed for elliptic curves over fields F(2m), as well as special elliptic curves such as Montgomery curves.

Abstract: A data cryptographer encrypts and decrypts character data of any given length using derivative equations and factors. The use of factors and derivative equations introduces the randomness required for effective encryption without the use of complex mathematics. A set of equations determined by the user is used in a manner similar to a key but with random results. Only a portion of the key is exposed to decrypt the encrypted information. The data cryptographer may be configured using either simple or complex equations and may be implemented in an unlimited number of variations. The data cryptographer is portable, and can be implemented in any programming language that supports cyclical character manipulation. The data cryptographer also supports input from a variety of sources, allowing control from the administrator side, string value side, or any other input that may be extracted from the desired programming language.

Abstract: A quantum cryptographic device provides authentication services over the optical (quantum) channel and the public channel. In one implementation, polarizers generate optical pulses that have a polarization state based on a bit from a first bit sequence. A polarization rotator further rotates the polarization basis of the optical pulse by a rotation angle specified by one or more bits of a second bit sequence. A receiving device receives the modulated optical pulses, demodulates the pulses, and may determine whether the optical channel can be authenticated. In an alternate implementation, phase modulation, instead of polarization modulation, is used to similarly modulate the optical pulses.

Abstract: Systems and methods provide encryption and decryption using wavelet transforms over finite fields. The wavelet encryption system and wavelet decryption system include one or more filters that receive a set of wavelet coefficients as input. The wavelet coefficients are then utilized by the wavelet encryption system to cause the filters to encrypt plaintext into cyphertext. The cyphertext is then decrypted by a wavelet decryption system, which is operable to reconstruct the original plaintext using wavelet transforms that reverse the effect of the wavelet encryption system.

Abstract: A system and method for quantum key distribution uses a regulated single-photon source to sequentially generate a first photon and a second photon separated by a time interval ?t. The two photons are directed through a beam splitter that directs each photon to one of two transmission lines, which lead to two respective receivers. When one of the photons arrives at a receiver, it passes through an interferometer. One arm of the interferometer has a path length longer than the other arm by an amount equivalent to a photon time delay of ?t. The photon is then detected in one of three time slots by one of two single-photon detectors associated with each of the two interferometer outputs. Due to quantum-mechanical entanglement in phase and time between the two photons, the receivers can determine a secret quantum key bit value from their measurements of the time slots in which the photons arrived, or of the detectors where the photons arrived.

Abstract: A method for protecting at least one first datum to be stored in an integrated circuit, including, upon storage of the first datum, performing a combination with at least one second physical datum coming from at least one network of physical parameters, and only storing the result of this combination, and in read mode, extracting the stored result and using the second physical datum to restore the first datum.

Abstract: A cryptographic system includes: a) a light source for generating an excitation light signal; b) a spatial light modulator for encoding the excitation light signal with data; c) a wavelength dispersive element for transforming the excitation light signal into a spectral encoded light signal characterized by relative peak intensities at specific wavelengths; d) an optical detector for generating an information output signal in response to receiving an optical input signal, wherein the information output signal represents spectral and intensity characteristics of the optical input signal; and e) a processor for validating the information output signal if differences between representations of the optical input signal, and representations of the spectral encoded light signal are within predetermined limits.

Abstract: A cryptographic method and related implements the Rijndael—AES encryption standard. In one improvement, the decryption round keys are generated on a round by round basis from the final Nk round keys saved from a previous encryption key scheduling operation. Latency and memory requirements are thereby minimized. S-boxes for the AES key generation and cipher operation itself, may be implemented multiple times in different ways with different power signatures, with a pseudo-random selection of the pathway for the different bytes to be substituted. The premix operation occurs simultaneously with the generation of first round keys, and a dummy circuit with substantially identical timing as the real premix circuitry adds power consumption noise to the premix.

Abstract: A method of deterministically generating maximal nonlinear block substitution tables for a predetermined block size is disclosed. The method includes selecting a first generating function and selecting a second generating function. The method also includes selecting first and second sets of complete linearly independent numbers, and calculating first and second linear orthomorphisms from the generating functions and the sets of linearly independent numbers. The method further includes creating maximal nonlinear block substitution tables by combining the linear orthomorphisms. The block substitution tables are for use in encrypting clear text messages.

Abstract: The present invention is a compression method for compressing digital data. The data is strings of digital values, which can be broken down to a series of 1's and 0's. The present inventive method uses a chaotic system to compress the data. The first step in the inventive method is generating a plurality of periodic orbits that correspond to a plurality of control bit strings. Each of the periodic orbits is formed with a series of numeric values. The next step is to convert the numeric values of the periodic orbits to digital data values, similar in form to the data to be compressed. The digital data values of the periodic orbits are then organized to identically match the original digital data values. Then the control bit strings corresponding to the organized digital data values of the periodic orbits are identified and saved in order, such that applying the control bit strings to the chaotic system will regenerate the original data.

Abstract: A cryptographic method of protection against fraud in transactions between an application and an electronic chip of a user. Both the electronic chip and the application compute a certificate (Sp, S) which is the result of applying a non-linear function f to a list of arguments (e1, e2) comprising at least a seed R and a secret key KO. A second secret key K? which is known only to the electronic chip and to the application is allocated to and kept secret in the electronic chip. Upon each authentication of the electronic chip, a mask M is determined by computing it from at least a portion of the secret key K?. The value of the certificate (Sp) is masked by means of the mask M to make available to the application only the masked value of the certificate (Spm). The application is used to verify the masked value of the certificate (Spm) computed by the electronic chip.

Abstract: The invention relates to a chaotic signal transmitter using a pulse shaping method to amplitude-modulate a chaotic signal according to a transmission signal, thereby transmitting the chaotic signal having various slopes. The chaotic signal transmitter includes a waveform converter for blocking high frequency component of the transmission signal to convert the waveform of the transmission signal and a chaotic signal generator for generating the chaotic signal. The chaotic signal transmitter further includes a modulator for amplitude-modulating the chaotic signal according to the waveform-converted transmission signal.

Abstract: The invention relates to a chaotic transmitter which can precisely measure a distance between the transmitter and a receiver, thereby efficiently regulating transmission power according to the distance. The chaotic signal transmitter includes a chaotic signal generator for generating a chaotic signal and a quantizer for quantizing a transmission signal with a predetermined number of steps. The chaotic signal transmitter also includes a modulation controller for controlling the modulation of the chaotic signal according to the quantized transmission signal. The chaotic signal transmitter further includes a modulator for modulating the chaotic signal from the chaotic signal generator in a multiple OOK mode to output a plurality of chaotic signals and a combiner for combining the plurality of modulated chaotic signals.

Abstract: A cryptographic key 1 constituted to be freely attachable and detachable to/from a personal computer 2 encrypting and decrypting data by use of a cipher key includes: a pseudo random number generator 14 for generating a pseudo random number of a chaotic time series based on a data size of the data, a chaotic function and an initial value of the chaotic function; and a USB controller 12 for receiving the data size of the data from the personal computer 2 and transmitting the pseudo random number of the chaotic time series as the cipher key to the personal computer 2, the pseudo random number being generated in the pseudo random number generator 14, when the cryptographic key 1 is attached to the personal computer 2.

Abstract: A radio frequency (RF) communication system having a chaotic signal generator and a method of generating a chaotic signal. The RF communication system includes a chaotic signal generator which generates a chaotic signal having a plurality of frequency components at a predetermined frequency band, a modulator which generates a chaotic carrier by combining the chaotic signal with a data signal which indicates information, and a transmission circuit which includes an antenna to transmit the chaotic carrier made at the modulator. The frequency signal generator comprises an oscillator which converts a DC bias power into a high frequency power, and a resonating unit which generates a wideband signal having a plurality of frequency components by passing a predetermined frequency band of the high frequency power signal.

Abstract: A method and apparatus for encryption of data are provided, in which the data is made up of a series of data items (600). The data items (600) maybe bytes of data or blocks of data. The method includes providing a plurality of encryption algorithms (604), selecting when to change encryption algorithm (601), selecting which encryption algorithm to change to (603), wherein each selection is carried out by applying a Chaotic and/or Catastrophic equation. The plurality of encryption algorithms (604) have index numbers and the generation of an index number by applying the Chaotic or Catastrophic equation selects an encryption algorithm. The selection of when to change encryption algorithm may be determined by a Catastrophic event in the Catastrophic equation and the selection of encryption algorithm may be determined by the surface of a Catastrophic curve on which a point lies, wherein each surface corresponds to an encryption algorithm.

Abstract: The present invention relates to a method of encryption and decryption comprises the steps of: selecting a generator and a first element of a first non abelian group, respectively, computing a first inner automorphism which is used as a first public key, and generating a second public key by using a secret key being a first integer and the first public key; expressing a plain text by a product of generator of a second non abelian group, computing a second inner automorphism by using an arbitrary second integer and the first public key, computing a third inner automorphism by using the second integer and the second public key, and generating a ciphertext by using the third inner automorphism; and generating a fourth inner automorphism by using the secret key and the second inner automorphism, and decrypting the ciphertext by using the fourth inner automorphism.

Abstract: The present invention provides data encryption for a differential bus employing transitional coding. The present invention maps, encodes and encrypts input data as a logic status for a given bus transfer cycle. The mapping, encoding and encrypting of the input data changes from bus transfer cycle to bus transfer cycle. The mapping, encoding and encrypting is a function of a pseudo-random number. A logic status is differentially transmitted from a bus transmitter to a bus receiver, to be mapped, decrypted and decoded as the corresponding output data.

Abstract: A chaotic communication system employs transmitting and receiving chaotic oscillating circuits. One improvement to first-generation systems is the ability to modulate a nonreactive element in the transmitting circuit, thus increasing modulation bandwidth. Other features include insertion of a gain control amplifier in a chaotic receiver; signal filtering in chaotic transmitters and receivers; use of chaotic modulation techniques for cellular telephony applications; dual-transmitter and receiver systems; a dual receiver synchronization detector; interfaces to communication systems; analog chaotic signal modulation; use of multiple chaotic transmitters and receivers; digital algorithm improvement using a cube-law nonlinear component; a Gb-only receiver; a Gb-only transmitter; and positive slope transmitter and receiver systems.

Abstract: Methods and systems for generating calibrated optical pulses in a QKD system. The method includes calibrating a variable optical attenuator (VOA) by first passing radiation pulses of a given intensity and pulse width through the VOA for a variety of VOA settings. The method further includes resetting the VOA to minimum attenuation and sending through the VOA optical pulses having varying pulse widths. The method also includes determining the power needed at the receiver in the QKD system, and setting the VOA so that optical pulses generated by the optical radiation source are calibrated to provide the needed average power. Such calibration is critical in a QKD system, where the average number of photons per pulse needs to be very small—i.e., on the order of 0.1 photons per pulse—in order to ensure quantum security of the system.

Abstract: Methods, apparatus, and systems are provided for distributing a key between nodes. The nodes are provided separate links for carrying messages versus keying information or material. The links for carrying messages couple the nodes to a messaging network, such as the Internet. In addition, the nodes are coupled together in a key distribution network by specialized links for carrying keying information or material. The links for keying information or material are configured to ensure the security of the keying information or material. The nodes that neighbor each other in the key distribution network establish respective pairwise keys. Once the pairwise keys are established, a set of non-neighboring nodes establish a shared key by communicating a sequence of bits through the messaging network. In order to ensure the security of the sequence of bits, the sequence of bits is encrypted based on the respective pairwise keys of neighboring nodes as it is forwarded in messages through the messaging network.

Abstract: A pseudo random generator comprising a shift register comprising a first flip flop (F0) and n further flip-flops (F1 . . . Fn) each flip-flop (F0) having a D input, a non-inverting output, an inverting output, and a common clock (fclk) input and the first flip-flop (F0) having a set input, each of the non-inverting outputs being connected via a NOR gate (10) to the set input of the first flip-flop (F0) and each of the non-inverting outputs of the flip-flops (F0 . . . Fn) being connected to the input of the first flip-flop (F0) via an XOR gate (11), characterised in that the generator comprises at least one additional logic gate (13, 14, 15; 17, 18, 19) including at least one additional flip-flop (14;18). The extra logic gates may comprise gated to toggle between the inverting end and the non-inverting outputs, or to generate an extra ‘0’ at the output or to chop, preferably randomly, the input signal.

Abstract: A method and apparatus that uses the dynamics of chaotic systems for the remote generation of a digital key, for use in any encryption algorithm. After initialization, the dynamics of a chaotic system are allowed to generate the 0 and 1 bits of a key bitstream. An initialization bitstream is transmitted, using conventional transmission technologies, to an identical chaotic system. This chaotic system is driven into synchrony and allowed to generate a key bitstream, which is identical to the other bitstream because the chaotic systems have been synchronized.

Abstract: A system for the compression and decompression of sections of audio files is provided. A library of basic waveforms is produced by applying selected digital initialization codes to a chaotic system. Each basic waveform is in one-to-one correspondence with an initialization code. A weighted sum of the selected basic waveforms is used to approximate a section of audio file. The basic waveforms are then discarded and only the weighting factors and the corresponding initialization codes are stored in a compressed audio file. When the compressed audio file is decompressed for playback, the stored initialization codes are stripped out and applied to a similar chaotic system to regenerate the basic waveforms, which are recombined according to the stored weighting factors to reproduce the original section of audio file.

Abstract: A method and a circuit for generating a secret quantity based on an identifier of an integrated circuit, in which a first digital word is generated from a physical parameter network, and this first word is submitted to at least one retroaction shift register, the output of the shift register forming the secret quantity.

Abstract: A quantum cryptography communication system includes a first data communication unit; a second data communication unit connected with the first data communication unit by a first optical fiber; and a third data communication unit connected with the second data communication unit by a second optical fiber. A first shared key is generated in the first data communication unit and the second data communication unit, and a second shared key is generated in the second data communication unit and the third data communication unit. The second data communication unit encrypts the first shared key by using the second shared key and then transmits the encrypted first shared key to the third data communication unit on the second optical fiber, and the third data communication unit decrypts the encrypted first shared key by using the second shared key to reproduce the first shared key.