A continuous variable quantum secret sharing method

Abstract

This invention discloses a continuous-variable quantum secret sharing method, relating to the field of quantum communication; specifically, it includes: first, constructing a communication scenario; n participants and 1 distributor each include s quantum modules and t classical modules; then, grouping all quantum modules and classical modules; next, selecting from the participants one by one, for each participant, randomly selecting the number of classical modules to group from the s quantum modules, and then sharing the quantum state S. ir Each classical module sent to each participant is recovered and post-processed using the VSS protocol to obtain s sets of keys for each participant. After concatenation and private key amplification, the final key for each participant is obtained, enabling each participant to share the key distributed by the distributor. This invention uses multiple quantum modules combined with private key amplification technology and multiple classical modules combined with VSS technology to resist hacker attacks targeting non-ideal quantum modules and non-ideal classical modules in the quantum secret sharing protocol.

Description

Technical Field

[0001] This invention relates to the field of quantum communication technology, specifically a method for sharing quantum secrets of continuous variables. Background Technology

[0002] Private key amplification (SIAM J. Comput. 17, 210–229) is a technique that uses a hash algorithm to compress a key, which can remove part of the key information obtained by an eavesdropper and generate a secure key.

[0003] Verifiable Secret Sharing (VSS) is a secure multi-party communication technique in classical cryptography. It can securely distribute and reconstruct secrets even when there are a certain number of dishonest parties in a group.

[0004] Quantum Secret Sharing (QSS) is a practical multi-party quantum communication technology that combines quantum physics and classical information theory to achieve unconditionally secure secret sharing through quantum means. In a quantum secret sharing protocol, the dealer and the player prepare a quantum state using a quantum module (containing devices such as lasers and modulators) at their local secure station. This quantum state information is then sent to a classical module, which performs classical post-processing to ultimately obtain the same secret.

[0005] The earliest quantum secret-sharing protocol was first proposed by Hillery et al. in 1999 (Phys. Rev. A 59, 1829), which used GHZ entangled states to ensure the security of secret sharing. To improve the practicality of quantum secret sharing, Schmid et al. (Phys. Rev. Lett. 95, 230505) proposed a single-photon sequential quantum secret-sharing protocol in 2005. This protocol does not utilize entanglement properties, but instead uses a method where all participants perform polarization rotation on the same photon to complete the secret sharing, thus greatly reducing the difficulty of system implementation.

[0006] In the field of continuous variables, Grice et al. (Phys.Rev.A100,02233) proposed a continuous variable quantum secret sharing protocol that does not utilize entanglement properties. The distributor and multiple participants generate secure keys respectively, thereby realizing (n,n) threshold quantum secret sharing, improving the tolerance to noise and loss, and can be extended to the case of a large number of participants, increasing the practicality of quantum secret sharing. Summary of the Invention

[0007] Based on existing technologies, in order to overcome the vulnerability of quantum secret sharing to attacks targeting non-ideal quantum and classical devices, this invention provides a continuous variable quantum secret sharing method. This method uses multiple quantum modules and multiple classical modules to complete the quantum state preparation and classical post-processing processes respectively, based on the original quantum secret sharing protocol. Combined with private key amplification and VSS technology, it can resist hacker attacks on non-ideal devices by eavesdroppers, while not changing other steps of the original protocol, thus improving the security of quantum secret sharing.

[0008] The specific steps of the continuous variable quantum secret sharing method are as follows:

[0009] Step 1: Construct a communication scenario for sharing quantum secrets for n participants and 1 distributor;

[0010] Each person consists of s quantum modules and t classical modules; each quantum module is connected to t classical modules; each classical module is connected to the remaining t-1 classical modules.

[0011] In all quantum modules, those with the same serial number are connected together; all classical modules with the same serial number are connected together, and all connections are made through secure channels.

[0012] Step 2: Group all quantum modules of the distributor and n participants, and group all modules with the same index into one group;

[0013] All quantum modules are divided into s groups, denoted as {Q1, Q2, ... Q...} s Each group contains n+1 quantum modules, and the s-th group is represented as {Q}. s1 Q s2 ,...Q s(n+1)};

[0014] Step 3: Simultaneously, each person selects tt′ items from their own classic modules to obtain... Classic modules;

[0015] t′ represents the number of non-ideal classical modules, and satisfies t′<t / 3;

[0016] Step 4: Select from the participants one by one. For the i-th participant, randomly select r quantum modules from the s quantum modules, corresponding to r shares of quantum state information S. ir ;

[0017] Each quantum module corresponds to its own quantum state information;

[0018] Step 5, Quantum State Information S irEach classic module of the i-th participant is sent through a secure channel, and the classic module is restored using the VSS distribution protocol and the reconstruction protocol.

[0019] Specifically: For the tt′ classic modules of the i-th participant, each classic module first exchanges its received S data through a secure channel. ir Determine if all are identical; if so, then set S... ir Send the remaining classic modules (excluding the tt′ classic modules) to the i-th participant; otherwise, terminate the scheme.

[0020] Other classic modules continue to exchange the S they have received. ir Determine if S ir Does it occur more than Next, if so, then S is considered... ir Correct; otherwise, the plan is terminated.

[0021] Step 6: Process the recovered quantum state information S ir After performing classic post-processing, we obtain s sets of keys for the i-th participant: K1, K2, ..., K s ;

[0022] Each quantum module of the i-th participant corresponds to a set of keys, and the length of each set of keys is N.

[0023] Step 7: The classic module concatenates the s sets of keys to obtain K. i The private key is amplified to obtain the final key of the i-th participant, which is shared with the key distributed by the distributor to the i-th participant.

[0024] The final key length is (ss′)×N; s′ represents the number of non-ideal quantum module groups;

[0025] Step 8: Return to Step 4, select the next participant and obtain the corresponding final key, and finally realize that n participants share the keys distributed to them by the distributor.

[0026] When the number of quantum module groups s′ with non-ideal quantum modules satisfies s′<s and the number of non-ideal classical modules t′ per person satisfies t′<t / 3, an eavesdropper cannot obtain any information about the final key through an attack targeting non-ideal devices.

[0027] The advantages of this invention are:

[0028] 1) A continuous variable quantum secret sharing method, which, without changing the original quantum secret sharing protocol, uses multiple quantum modules combined with private key amplification technology to resist hacker attacks targeting non-ideal quantum modules in the quantum secret sharing protocol.

[0029] 2) A continuous variable quantum secret sharing method that uses multiple classical modules combined with VSS technology can resist hacker attacks targeting non-ideal classical modules in the quantum secret sharing protocol. Attached Figure Description

[0030] Figure 1 This invention constructs a secret sharing scenario consisting of multiple quantum modules and multiple classical modules.

[0031] Figure 2 This is a flowchart of a continuous variable quantum secret sharing method according to the present invention. Detailed Implementation

[0032] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0033] This invention utilizes multiple quantum modules and multiple classical modules to complete the quantum state preparation and classical post-processing of quantum secret sharing. Assume that n participants and one distributor each use s quantum modules and t classical modules respectively in a secure station to share quantum secrets. All participants' quantum modules are grouped together to complete the quantum state preparation process, and each person's t classical modules complete the classical post-processing process. When the number of non-ideal quantum module groups s′ satisfies s′<s and the number of non-ideal classical modules per person t′ satisfies t′<t / 3, the method proposed in this invention can resist attacks targeting non-ideal devices.

[0034] The continuous-variable quantum secret sharing method includes independently operable steps: quantum state preparation using multiple quantum modules and classical post-processing using multiple classical modules; such as... Figure 2 As shown, the specific steps are as follows:

[0035] Step 1: Construct a communication scenario for sharing quantum secrets for n participants and 1 distributor;

[0036] like Figure 1 As shown, each person consists of s quantum modules and t classical modules; each quantum module is connected to t classical modules; each classical module is connected to the remaining t-1 classical modules.

[0037] In all quantum modules, quantum modules with the same index are connected together; all classical modules with the same index are connected together, and all connections are made through secure channels (i.e., channels that cannot be eavesdropped on).

[0038] Step 2: Group all quantum modules of the distributor and n participants, and group all modules with the same index into one group;

[0039] All quantum modules are divided into s groups according to their serial numbers, denoted as {Q1, Q2, ... Q...}s Each group contains n+1 different quantum modules with the same index, denoted as {Q} for the s-th group. s1 Q s2 ,...Q s(n+1)};

[0040] Each quantum module corresponds to its own quantum state information;

[0041] Step 3: Simultaneously, the distributor and n participants each randomly select tt′ from their t classic modules, resulting in... Classic modules;

[0042] Let t′ represent the number of non-ideal classical modules, and satisfy t′<t / 3; each person randomly selects tt′ different modules to form a group, so each person has

[0043] Step 4: Select from the participants one by one. For the i-th participant, randomly select r quantum modules from the s quantum modules, corresponding to r shares of quantum state information S. ir ;

[0044] Step 5, Quantum State Information S ir The information is sent to each classical module of the i-th participant via a secure channel. The classical module uses the VSS distribution protocol and the VSS reconstruction protocol to recover the initial quantum state information.

[0045] The VSS distribution protocol will S ir The information is sent to each classical module separately, and each classical module reconstructs it using the VSS reconstruction protocol. Finally, each classical module recovers the initial quantum state information.

[0046] Specifically: For the tt′ classic modules of the i-th participant, each classic module first exchanges its received S data through a secure channel. ir Determine if all are identical; if so, then set S... ir Send the remaining classic modules (excluding the tt′ classic modules) to the i-th participant; otherwise, terminate the scheme.

[0047] Other classic modules continue to exchange the S they have received. ir Determine S ir Does it occur more than Next, if so, then S is considered... ir Correct; otherwise, the plan is terminated.

[0048] Step 6: Process the recovered quantum state information S ir After performing classic post-processing, we obtain s sets of keys for the i-th participant: K1, K2, ..., K s ;

[0049] Each quantum module of the i-th participant corresponds to a set of keys, and the length of each set of keys is N.

[0050] Step 7: The classic module concatenates the s sets of keys to obtain K. i The private key is amplified to obtain the final key of the i-th participant, which is shared with the key distributed by the distributor to the i-th participant.

[0051] The final key length is (ss′)×N; s′ represents the number of non-ideal quantum module groups;

[0052] Step 8: Return to Step 4, select the next participant and obtain the corresponding final key, and finally realize that n participants share the keys distributed to them by the distributor.

[0053] Example:

[0054] (1) Group all quantum modules of the distributor and n participants, with all modules having the same index grouped together. Therefore, there are s groups of quantum modules, denoted as Q. i (i = 1, 2, ..., s); each group contains n+1 quantum modules, denoted as Q. ij (j = 1, 2, ..., n+1). Each person also groups their own classic modules, selecting t' different modules each time to form a group, thus each person has... A group of classical modules, the classical module group corresponding to the j-th quantum module is represented as C. jk (k = 1, 2, ..., r).

[0055] For example, regarding the second quantum module Q in group 1 12 If t takes the value 6 and t′ takes the value 1, then every 5 classic modules form a group, and r takes the value 6.

[0056] (2) Each participating quantum module needs to perform the quantum state preparation process of the original quantum secret sharing protocol, and a total of s sets of quantum states are prepared; each quantum module of the distributor needs to perform the quantum state preparation or detection process of the original quantum secret sharing protocol.

[0057] (3) For the j-th quantum module Q in the i-th group ij The VSS distribution protocol is used to distribute to the corresponding C. jk Each classical module in the system distributes quantum state information S. ij :

[0058] (4)C jk All classic modules are restored using the VSS refactoring protocol:

[0059] First Cjk The tt′ classic modules in the system exchange their received S signals via a secure channel. ij Determine if there are tt' S ij If they are the same, then C jk All classic modules will transmit S through a secure channel ij Send to the remaining classic module group C in the security station jk′ The classic module in (k′=1,2,...,r and k′≠k). Otherwise, the solution terminates;

[0060] C jk′ The tt' classic modules in the middle exchange their received shares again. If a certain share appears more than 100 times... Then it is identified as S. ij .

[0061] (5) Through the above steps, all quantum modules securely transmit s sets of quantum state information to all classical modules in their respective security stations. Subsequently, the classical modules utilize the recovered quantum state information to perform classical post-processing according to the post-processing procedure of the original quantum secret sharing protocol, ultimately obtaining s sets of keys K1, K2, ..., K. s Each key has a length of N.

[0062] (6) The classic module concatenates the s sets of keys to obtain K = [K1, K2, ..., K s The private key is amplified to obtain a final key of length (ss′)×N. When the number of quantum module groups s′ with non-ideal quantum modules satisfies s′<s and the number of non-ideal classical modules t′ per person satisfies t′<t / 3, the eavesdropper cannot obtain any information about the final key through attacks targeting non-ideal devices.

Claims

1. A continuous-variable quantum secret sharing method, characterized in that, The specific steps are as follows: Step 1: Construct a communication scenario for sharing quantum secrets for n participants and 1 distributor; Each person consists of s quantum modules and t classical modules; Step 2: Group all quantum modules of the distributor and n participants, and group all modules with the same index into one group; Step 3: Simultaneously, each person selects tt′ items from their own classic modules to obtain... Classic modules; t′ represents the number of non-ideal classical modules, and satisfies t′<t / 3; Step 4: Select from the participants one by one. For the i-th participant, randomly select r quantum modules from the s quantum modules, corresponding to r shares of quantum state information S. ir ; Each quantum module corresponds to its own quantum state information; Step 5, Quantum State Information S ir Each classic module of the i-th participant is sent through a secure channel, and the classic module is restored using the VSS distribution protocol and the reconstruction protocol. Specifically: For the tt′ classic modules of the i-th participant, each classic module first exchanges its received S data through a secure channel. ir Determine if all are identical; if so, then set S... ir Send the other classic modules to the i-th participant, excluding the tt′ classic modules; Otherwise, the plan will be terminated; Other classic modules continue to exchange the S they have received. ir Determine if S ir Does it occur more than Next, if so, then S is considered... ir Correct; otherwise, the plan is terminated. Step 6: Process the recovered quantum state information S ir After performing classic post-processing, we obtain s sets of keys for the i-th participant: K1, K2, ..., K s ; Step 7: The classic module concatenates the s sets of keys to obtain K. i The private key is amplified to obtain the final key of the i-th participant, which is shared with the key distributed by the distributor to the i-th participant. The final key length is (ss′)×N; s′ represents the number of non-ideal quantum module groups; Step 8: Return to Step 4, select the next participant and obtain the corresponding final key, and finally realize that n participants share the keys distributed to them by the distributor.

2. The continuous variable quantum secret sharing method as described in claim 1, characterized in that, In the communication scenario described in step one, each quantum module is connected to t classical modules; each classical module is connected to the remaining t-1 classical modules. In all quantum modules, those with the same serial number are connected together; all classical modules with the same serial number are connected together, and all connections are made through secure channels.

3. The continuous variable quantum secret sharing method as described in claim 1, characterized in that, In step two, all quantum modules are divided into s groups, denoted as {Q1, Q2, ... Q...} s Each group contains n+1 quantum modules, and the s-th group is represented as {Q}. s1 Q s2 ,...Q s(n+1) } 4. The continuous variable quantum secret sharing method as described in claim 1, characterized in that, In step six, each quantum module of the i-th participant corresponds to a set of keys, and the length of each set of keys is N.

5. A continuous variable quantum secret sharing method as described in claim 1, characterized in that, In step eight, when the number of quantum module groups s′ with non-ideal quantum modules satisfies s′<s, and the number of non-ideal classical modules t′ per person satisfies t′<t / 3, the eavesdropper cannot obtain any information about the final key through attacks targeting non-ideal devices.

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