48 results about "Quantum secret sharing" patented technology

The invention discloses a method for attacking Fourier transform quantum secret sharing systems, and relates to quantum secret communication technology. In the method, a specific measurement base is utilized to perform single particle measurement on the information carrier quantum bit, and partial secret messages are acquired according to a measurement result. According to the quantum-mechanical nature, due to the selection of the measurement base, the state of the measured quantum bit is just the eigen state of the measurement base, and the quantum state after measurement cannot be changed at all. The method can make a dishonest agent independently obtain partial key information, also can make several cooperated agents obtain more key information, and cannot introduce any error for normal communication so as not to be discovered by other users. The invention provides a method for effectively attacking the Fourier transform quantum secret sharing systems, which is simultaneously an effective method for testing the safety of the Fourier transform quantum secret sharing systems.

The invention relates to an error correction method for a multi-party quantum secret sharing system. The error correction method comprises the following steps: S1: calculating a system error rate; S2: according to the system error rate, finding the optimal segment length sequence; S3: performing the following steps through loop iteration: S3.1: rearranging data; S3.2: according to the optimal segment length, segmenting an original key of a transmitter and a shared key; calculating parity check sums of segment keys at a transmitting end and a receiving end respectively, and comparing operational results of the transmitting end and the receiving end to obtain the segment keys with different operational results; S3.3: finding error bit positions by a Winnow error correction algorithm; S3.4: according to the error bit positions, negating 0 or 1 values at corresponding positions in the original key of the transmitter, and stopping loop iteration till the maximum number of iterations is reached; S4: checking error correction results; if error correction is successful, ending operation; if the error correction is not successful, discarding the corresponding keys. The invention provides the error correction method which is high in reliability and high in error correction efficiency and is applicable to the multi-party quantum secret sharing system.

The invention discloses a high-capacity quantum secret sharing method based on photon orbit angular momentum coding. The method comprises the steps: constructing two unitary operators; giving two groups of complete intrinsic quantum states; carrying out annular quantum secret sharing communication. Based on an intrinsic quantum state space, transmitter side Alice randomly prepares a photon sequence and transmits the photon sequence to Bob. Bob randomly selects verification photons from the photon sequence for measurement described in the specification. The coding of the residual photons is carried out according to a secret key character string, and the coded photons are transmitted to Charlie. Charlie carries out measurement of photon verification of the received photon sequence, and codes the residual photons according to the secret key character string, and transmits the coded photons to Alice. Alice judges whether a communication channel is safe or not, and reads the coding operation which is carried out by Bob and Charlie jointly. The method employs single-photon orbit angular momentum coding to improve the communication capacity and frequency spectrum efficiency of a quantum secret sharing scheme, and does not need multicomponent entangled photon states.

The invention belongs to the technical field of quantum information sharing, and discloses a quantum secret sharing method and sharing system based on quantum walk, and the method comprises the steps:enabling a secret distributor to encode secret information to be shared into a quantum state according to a rule, and enabling an encoding particle to be split into two parts; invisibly transferringthe two pieces of encrypted information to a first participant and a second participant through a quantum walking system; and the first participant and the second participant decrypt the secret information of the secret distributor through cooperation. Characteristics of the quantum walking system are used for invisible state transfer of unknown particles, entanglement is spontaneously generated among the particles, and preparation of entangled particles in a particle preparation stage is avoided to complete invisible state transfer of the particles. According to the quantum secret sharing method based on quantum walking, an invisible state transfer method based on quantum walking is combined with a coding rule, and the quantum secret sharing method based on quantum walking is completed.

The invention belongs to the technical field of information security, and discloses a quantum secret sharing method capable of resisting an intercept-resend attack, a man-in-the-middle attack and an entanglement attack. A secret sharing protocol is designed by utilizing the special characteristic that a five-particle GHZ state has the correlation in an X group. According to the protocol, secret information is split into four parts, the four parts are delivered to four participators to be cared, and the secret information can be decrypted only when the four participators all take participate in. After analysis, the feasibility of the protocol is proved. Security analysis shows that the protocol can resist the intercept-resend attack, the man-in-the-middle attack and the entanglement attack. And meanwhile the trust problem of the participators is analyzed, and it shows that the protocol is secure.

The invention discloses a verifiable threshold quantum secret sharing method for sequential communication, which can recover the secret cooperatively without the participation of all shareholders, sothat the method has more flexibility in application. At that same time, no trusted third party is need, and a verifiable mechanism is provided to detect cheat, so that the security is guarantee, in addition, each round can be legally used for secret sharing, and the practicability is greatly improved.

The invention relates to the technical field of quantum communication, and especially relates to a sharing method of a quantum secret sharing system. The method comprises the following steps: S1: calculating a system error rate; S2: determining a check matrix according to the system error rate; S3: obtaining a check code of an initial key according to the check matrix; S4: performing error correction on a logical operation result of the initial key and a shared key of a receiving terminal by using the check code of the initial key; S5: judging whether the error correction is successful; S6: if the error correction is successful, stopping the operation; and if the error correction is not successful, then adjusting the code rate to obtain a new initial key and a new shared key, and executing steps S3 to S6 by the initial key and the shared key with the code rate adjusted until the error correction is successful or a preset maximum error correction time is reached. The invention further relates to a quantum secret sharing system and a sharing method thereof. According to the sharing method provided by the invention, multi-party information interaction is adopted, the original key is sent to at least two receiving terminals by a sending terminal, and the problems of dissipation, error code and the like in a secret sharing process are reduced.

The invention provides a quantum secret sharing method and system without a monitoring channel, and the method comprises the steps: two transmitting ends prepare a bit string with the length of L, enabling the generated bit string information to be coded on the phase of a quantum state with the dimension of L, and transmitting a quantum state sequence to a receiving end; the receiving end performsshift type interference measurement on the two paths of quantum state sequences, generates an original secret key according to a measurement result, and then publishes the positions of the quantum states which are responded under effective measurement to the two sending ends respectively; the two receiving ends find out corresponding bits from own bit strings as original keys according to the positions of the quantum states; and finally, classical error correction, error verification and privacy amplification are performed by the three parties, and finally extracting is performed to obtain akey for quantum secret sharing. According to the method, the requirement of channel monitoring is removed, and theoretically the highest 50% system bit error rate can be tolerated, so that the deviceand the implementation program of the quantum secret sharing scheme are simpler.

The invention belongs to the technical field of semi-quantum communication, and discloses a multi-party semi-quantum secret sharing method and system based on a single photon. The multi-party semi-quantum secret sharing method comprises the steps that a secret distributor splits a classic information code into quantum states; and the participant receives the quantum state through semi-quantum cryptography communication, then recovers a part of secret information through quantum operation, and recovers original secret information through honesty cooperation. The secret sharing scheme does not depend on entangled-state particles, but adopts single particles, so that the secret sharing scheme has higher practicability in practice; according to the protocol, a classic party does not need to have complete quantum capacity, and the requirement for quantum equipment resources is lowered; according to the multi-party semi-quantum secret sharing method, secret sharing between a secret distributor and multiple parties is completed, but not limited to secret sharing among the three parties; and according to the scheme, internal attacks and external entanglement attacks can be resisted, and safety feasibility is achieved.

The invention belongs to the technical field of information security. The invention discloses an authenticable semi-quantum secret sharing method and system based on a GHZ state, and the method comprises the steps: enabling a strong quantum party to share an n-bit message m secret to a first semi-quantum party and a second semi-quantum party, and obtaining a secret message m after the first semi-quantum party and the second semi-quantum party both know the coding results of the other two parties; by utilizing an absolutely safe quantum key distribution technology, the strong quantum party and the first semi-quantum party sharing keys key ab1 and key ab2; the strong quantum party and the second semi-quantum party sharing the keys keyac1 and keyac2; and the second semi-quantum party and the first semi-quantum party sharing the keybc. In the secret sharing process, bidirectional authentication of the user identity is completed at the same time, security analysis shows that the protocol can resist different attack strategies such as internal attacks and external attacks, and the secret key shared between the users can be used for multiple times; in addition, the method has good particle use efficiency, quantum resources can be saved, and three-party secret sharing can be completed efficiently.

The invention provides a quantum walking-based quantum secret sharing method with credible authentication. The method comprises the following steps: a secret participation end preparing single photonsequences SB and SC, encoding the SB and SC according to an identity authentication key of the secret participation end to obtain SB' and SC ', and sending the SB' and SC' to a secret distribution end; the secret distribution end authenticating the identity of the secret distribution end based on the identity authentication key of the secret participation end; the secret distribution end constructing two quantum walking systems based on the SB and the SC, encoding secret information to be shared to the SB and the SC, and recording secret information encoding particles as MB and MC; the secretdistribution end invisibly transmitting the MB and the MC to the secret participation end; the secret participation ends cooperating with each other to complete identity authentication of the secret distribution end and reconstruction of secret information. According to the trusted identity authentication function and the quantum walking circuit, the safety and practicability of the quantum secretsharing method and system can be improved, and interception/retransmission attacks, entanglement attacks, participant attacks and pretending attacks from the inside and the outside are avoided.

The invention discloses a continuous variable quantum secret sharing implementation method capable of autonomously selecting users, electronic equipment and a computer readable storage medium. The method comprises the steps: 1, enabling each participant to generate a dual-mode entangled state, carrying out the projection measurement of a mode A in the dual-mode entangled state, and transmitting a mode B to a data distributor to form original data; step 2, the data distributor selects legal participants from all participants, sorts the legal participants, calculates a regular part when each legal participant is a unique honest participant, and splits the initial secret information according to the regular part; 3, the data distributor sends the sub-secret information to each legal participant according to the sequence, and each legal participant processes the sub-secret information to obtain unique sub-secret information; 4, all the legal participants cooperate with one another to recover the initial secret information; according to the invention, the data distributor can autonomously select part of participants for communication, and the communication safety is improved.

The invention discloses a quantum secret sharing method based on a tensor network and a quantum communication system. A quantum state is reconstructed by utilizing a corresponding relationship betweenclassic information and quantum information; a distributor combines an AKLT model and a matrix product state representation method to realize secret division, and then distributes sub-secrets to participants through a classic authentication channel and a quantum channel; and finally, secret reconstruction is realized based on a tensor network state theory and a (n, n) threshold group recovery protocol. The extendability of secret information and the matrix product representation expandability, transfer characteristics and non-uniqueness of a quantum multi-body state are the biggest innovationpoints of the invention, safety and reliability of quantum communication are guaranteed, and the problem that dynamic construction cannot be achieved through existing quantum state secret sharing issolved. Diversity of matrix product state representation and simple graphic representation corresponding to the tensor network enable the method of the invention to have a good application prospect inthe field of quantum state sharing and information security in a quantum network.

This specification discloses a quantum public-key cryptosystem. The quantum public-key cryptosystem may use two rotation operators R_{{circumflex over (n)}}(θ) and R_{{circumflex over (m)}}(φ) satisfying a cyclic evolution. The two rotation operators R_{{circumflex over (n)}}(θ) and R_{{circumflex over (m)}}(φ) do not have a commutation relation or an anti-commutation relation with each other. The commutation relation or the anti-commutation relation is established when either of the following conditions is satisfied: θ=2iπ, φ=2jπ, or {circumflex over (n)}·{circumflex over (m)}=1 (i, j=integer), and θ=(2k+1)π, φ=(2l+1)π, or {circumflex over (n)}·{circumflex over (m)}=0 (k, l=integer).

The invention discloses a quantum secret sharing method based on a round-robin differential phase-shifting quantum key distribution protocol. The method comprises a secret distributor Alice and at least two participants Bob and Charlie; the distributor Alice divides one piece of information into two parts to respectively send to the Bob and the Charlie following the cyclic differential phase-shifting quantum key distribution protocol; and the information of the Alice can be acquired as long as the Bob and the Charlie mutually cooperate in honest. The single-photon light source is used in the method disclosed by the invention, the RRDPS-QKD protocol is applied to the quantum secret sharing, and higher noise tolerance and operation convenience are provided.

The semi-quantum secret sharing concept is popularized to a d-level quantum system, and the annular multi-party semi-quantum secret sharing method based on the d-level single-particle state is provided. In the method provided by the invention, the particles prepared by the quantum party are transmitted in an annular manner, and the classical party does not need to have the measurement capability.The method disclosed by the invention is safe to some famous attacks, such as intercept-resend attack, a measure-resend attack, an entangle-measure attack and a participant attack..