31 results about "Post-quantum cryptography" patented technology

A system stores pedigrees that include details of how and when each of multiple blocks of encryption key material were distributed between two endpoints using quantum cryptographic techniques. The system receives an indication of a possible quantum cryptographic security violation and accesses the stored pedigrees to identify one or more of the multiple blocks of encryption key material that may have been compromised.

A method of establishing a shared secret random cryptographic key between a sender and a recipient using a quantum communications channel is described. The method comprises: generating a plurality of random quantum states of a quantum entity, each random state being defined by a randomly selected one of a first plurality of bases in Hilbert space, transmitting the plurality of random quantum states of the quantum entity via the quantum channel to a recipient, measuring the quantum state of each of the received quantum states of the quantum entity with respect to a randomly selected one of a second plurality of bases in Hilbert space, transmitting to the recipient composition information describing a subset of the plurality of random quantum states, analysing the received composition information and the measured quantum states corresponding to the subset to derive a first statistical distribution describing the subset of transmitted quantum states and a second statistical distribution describing the corresponding measured quantum states, establishing the level of confidence in the validity of the plurality of transmitted random quantum states by verifying that the first and second statistical distributions are sufficiently similar, deriving a first binary sting and a second binary string, correlated to the first binary string, respectively from the transmitted and received plurality of quantum states not in the subset, and carrying out a reconciliation of the second binary string to the first binary string by using error correction techniques to establish the shared secret random cryptographic key from the first and second binary strings.

Provided are an auto-compensating quantum cryptography transceiver and method of transmitting a quantum cryptography key at a high speed. A quantum cryptography transmitter includes a wavelength converter, an optical attenuator, an optical phase modulator, and a Faraday mirror. A quantum cryptography receiver includes a polarization beam splitter, an optical coupler, an optical filter, and a photon detector. Thus, a limit of a transmission rate caused by Rayleigh scattering of an optical fiber can be overcome.

A network and a device can support secure sessions with both (i) a post-quantum cryptography (PQC) key encapsulation mechanism (KEM) and (ii) forward secrecy. The device can generate (i) an ephemeral public key (ePK.device) and private key (eSK.device) and (ii) send ePK.device with first KEM parameters to the network. The network can (i) conduct a first KEM with ePK.device to derive a first asymmetric ciphertext and first shared secret, and (ii) generate a first symmetric ciphertext for PK.server and second KEM parameters using the first shared secret. The network can send the first asymmetric ciphertext and the first symmetric ciphertext to the device. The network can receive (i) a second symmetric ciphertext comprising “double encrypted” second asymmetric ciphertext for a second KEM with SK.server, and (ii) a third symmetric ciphertext. The network can decrypt the third symmetric ciphertext using the second asymmetric ciphertext.

A cryptography method using a quantum phenomenon, which performs a multi-staged polarization process between a transmitter and a receiver to prevent a third party from knowing the polarization value of a photon. A transmitter rotates a photon flux by arbitrary angle θ and transmits it to a receiver. The receiver rotates the received photon flux by arbitrary angle φ and transmits it to the transmitter. The transmitter rotates the received photon flux by the reverse angle −θ of an angle, by which the transmitter 10 rotated it, then rotates it by polarization corresponding to an information bit, and transmits it to the receiver which rotates the received photon flux by the reverse angle −φ of an angle, and measures the polarization of the photon flux corresponding to the information bit, and recovers the information bit transmitted by the transmitter. Cryptography information may be transmitted using a plurality of photon fluxes.

The invention discloses a quantum cryptography network dynamic routing method. According to the method, dynamic routing selection of encryption communication is performed by utilizing quantum cryptography according to changes of the quantum key quantity between relay nodes of a quantum cryptography network. According to the method, a route server is arranged for the relay nodes of the whole quantum cryptography network, and topology refresh cycles of the quantum cryptography network are set; in each topology refresh cycle, each relay node collects and processes state information of the relay node and reports results to the route server. After the route server collects the topology state information of each relay node, quantum cryptography network topology state information of a next topology refresh cycle is generated and sent to all the relay nodes of the quantum cryptography network. According to the quantum cryptography network topology state information obtained from the route server, a target relay node is calculated and determined to be a next skip route of communication data of a random other relay node according to a shortest path law through each relay node.

A system, and methods, for transmitting encrypted information as a quantum transmission between a first node and a second node, or among more than two nodes. Each node is characterized by an instantaneous spatial position, and the instantaneous spatial position of the second node is repositionable within a frame of reference associated with the first node. A hovering drone is adapted either for running a quantum key transmission protocol in secure communication with the first node, and / or for running a quantum key reception protocol in secure communication with the second node. Either drone may serve as a relay of optical data between a base station and another drone. Secure communication among more than two nodes may be reconfigured.

A computer processing system for reducing a processing footprint in cryptosystems utilizing quadratic extension field arithmetic such as pairing-based cryptography, elliptic curve cryptography, code-based cryptography and post-quantum elliptic curve cryptography that includes at least one computer processor having a register file with three processor registers operably configured to implement quadratic extension field arithmetic equations in a finite field of Fp2 and a multiplexer operably configured to selectively shift from each of the three processor registers in sequential order to generate modular additional results and modular multiplication results from the three processor registers.

Provided is a polarization coding quantum cryptography system. The quantum cryptography includes a light source, a quantum channel, an optical path selector, and a path-dependent polarization selector. The light source generates a signal light. The quantum channel is used as a path to transmit the signal light to a receiver unit. The optical path selector is disposed between the light source and the quantum channel to transmit the signal light to one of a plurality of propagation paths. The path-dependent polarization selector is disposed between the optical path selector and the quantum channel. Herein, the path-dependent polarization selector is configured to determine the polarization direction of the signal light according to the propagation path of the signal light.

Provided is a quantum encryption communication apparatus of a transmission side which performs a communication process based on quantum encryption, including: a light source unit which generates a light pulse; a polarization modulating unit which performs polarization modulation of the light pulse by using a variable wavelength plate; and a controller which drives the variable wavelength plate to convert a polarization state of the light pulse to one of a plurality of predetermined polarization bases at random.

The invention discloses a codebook verifying method for quantum secret communication. The method comprises the following steps: a plurality of screening, comprising a plurality of grouping operation, comparison and rearrangement of codebooks, are implemented for original information of generated codebooks obtained through ALC and BOB to obtain the codebooks with higher credibility; then the obtained screened codebooks are integrally calculated to obtain one supervision code; if the supervision codes of two parties are consistent, the codebooks are reliable codebooks; otherwise, the codebooks are unreliable and directly discarded; the next group of codebooks is generated renewedly. Through using the codebook verifying method, the two parties for communication can obtain safe and reliable codebooks without disclosing one section of secret keys; the characteristics of stability and high efficiency are achieved. The codebook verifying method can be used for solving the problem for obtaining credible codebooks in the quantum secret communication, can improve the characteristics of secret reliable transmission of the quantum communication system, and has the characteristics of high efficiency and high stability.