Bidirectional quantum secret communication method for Internet of Things

Abstract

The invention discloses a bidirectional quantum secret communication method for the Internet of Things, and relates to the technical field of quantum communication, in the method, two communication parties employ a device authentication module based on the quantum principle to mutually verify identities, and then a bidirectional information transmission module which does not need the participation of a third party is used for communication; wherein the bidirectional information transmission module takes a product of three Bell states as a quantum channel. According to the invention, through realizing equipment authentication and quantum communication without a third party, the communication security and efficiency of the Internet of Things are improved, the system complexity and communication interference are reduced, and the threat of quantum computing to the network security is effectively dealt with.

Description

Technical Field

[0001] The present invention relates to the field of quantum communication technology, and in particular to a two-way quantum secure communication method for the Internet of Things. Background Art

[0002] The Internet of Things faces increasingly complex and diverse security threats, and security and privacy have become important concerns. Today, in terms of communication, the security of IoT communications mainly relies on asymmetric and symmetric cryptographic systems. In parallel development, quantum computers are emerging, which can quickly solve combinatorial problems that classical computers cannot solve with the help of superposition properties, so the development of quantum computing has begun to pose a real threat to the network security of the global digital infrastructure. At the same time, there are also a large number of IoT communication security researchers who are currently developing various solutions to mitigate this threat. In this regard, quantum secure communication may provide a promising solution. Compared with traditional encryption technology, quantum secure communication provides higher security and can maintain the confidentiality of communication even in the face of possible quantum computing attacks in the future. In addition, the combination of IoT security and quantum secure communication can bring several potential advantages. In terms of identity authentication, devices in the Internet of Things can use the quantum non-cloning principle and the quantum uncertainty principle for identity authentication to ensure that only legitimate devices can access and interact. This can prevent unauthorized device intrusion and information leakage. In terms of information security assurance, quantum teleportation is an important branch of quantum communication, which uses entangled states and classical communication channels to transmit information between parties. Devices in the Internet of Things can achieve a higher level of information security assurance through quantum teleportation technology. Therefore, it is necessary to study two-way quantum secure communication between devices in the Internet of Things environment.

[0003] Most of the solutions that have been proposed so far require the introduction of a third-party controller to assist communication equipment in completing device authentication and quantum communication. However, the introduction of a third-party controller may undermine the trust relationship between communication participants. If the communication participants cannot ensure the honesty and reliability of the third-party controller, the security and confidentiality of the communication cannot be ensured. On the other hand, the introduction of a third-party controller may increase interference in communication. In order to detect and counter such interference, more complex technologies and algorithms are required, which will increase the complexity and overhead of the IoT security system. Summary of the invention

[0004] The present invention provides a two-way quantum secure communication method for the Internet of Things, which can solve the above-mentioned problems.

[0005] In order to solve the above problems, the technical solution adopted by the present invention is as follows:

[0006] The present invention provides a bidirectional quantum secure communication method for the Internet of Things, in which both communicating parties use a device authentication module based on quantum principles to verify each other's identities, and then use a bidirectional information transmission module that does not require the participation of a third party to communicate; wherein the bidirectional information transmission module uses the product of three Bell states as a quantum channel.

[0007] As a further description of the above technical solution, during the device authentication process of the device authentication module, the communicating parties share a 2n-bit binary identity authentication string, the first n bits of the binary identity authentication string are used by the first communicating party to detect the identity of the second communicating party, and the last n bits are used by the second communicating party to detect the identity of the first communicating party.

[0008] As a further description of the above technical solution, a method for a first communication party to detect an identity of a second communication party includes the following steps:

[0009] S11: The first communication party generates an n-bit binary random sequence as an original selected bit string;

[0010] S12: The first communication party takes the first n bits of the binary identity authentication string as a selected base bit string, converts each bit of the original selected state bit string into a single photon polarization state, and then sends the obtained photon state to the second communication party;

[0011] S13: The second communication party selects a measurement basis according to the first n bits of the binary identity authentication string, measures the received photon state, obtains a binary random sequence, and sends it to the first communication party;

[0012] S14: The first communication party compares the original selected bit string with the binary random sequence measured by the second communication party to estimate the error. If the error is less than or equal to the security threshold, the first communication party believes the identity of the second communication party. If the error exceeds the security threshold, it means that the identity of the second communication party is in doubt or the communication has been eavesdropped, and the first communication party needs to end the communication.

[0013] As a further description of the above technical solution, a method for the second communication party to detect the identity of the first communication party includes the following steps:

[0014] S21: The first communication party takes the last n bits of the binary identity authentication string as a selected bit string;

[0015] S22: The first communication party generates an n-bit binary random sequence T a As the selected base bit value, each bit of the selected state bit string is converted into a single photon polarization state, and then sent to the second communication party;

[0016] S23: The second communication party generates an n-bit binary random sequence T bAs the selected base bit value sequence, measure the polarization states of n single photons transmitted by the first communication party, compare the measurement results with the selected state bit string, record the mismatching positions between the measurement results and the selected state bit string, and send them to the first communication party;

[0017] S24: The first communication party will not match the corresponding T a The value is sent to the second communication party, and the second communication party detects T at the corresponding position b Whether the value is the same as the Ta value sent by the first communication party, if different, the second communication party believes the identity of the first communication party, if the same, the identity of the first communication party is in doubt or the communication has been eavesdropped, and the second communication party needs to end the communication.

[0018] As a further description of the above technical solution, a physical noise source is selected to generate a binary random sequence.

[0019] As a further description of the above technical solution, the method for communicating using the two-way information transmission module includes the following steps:

[0020] S31: The communicating parties perform deformation operations on the unknown quantum entangled states they hold, and convert them into pure arbitrary states for transmission, and obtain the system state based on the pure arbitrary states;

[0021] S32: The communicating parties perform Z-basis single quantum measurement on the quantum bits corresponding to the particles carrying information in the system state;

[0022] S33: The two communicating parties inform each other of their measurement results in step S32 through the classical channel, and the two communicating parties apply unitary operations to the remaining quantum bits in the system state to obtain the target collapsed state;

[0023] S34: The communicating parties perform single quantum measurement on the X basis on the particle carrying information in the target collapsed state;

[0024] S35: The two communicating parties inform each other of their measurement results in step S34 through the classical channel, and the two communicating parties apply unitary operations to the remaining quantum bits after collapse to obtain the target state;

[0025] S36: The communicating parties introduce auxiliary quantum bits and perform the deformation operation in reverse to reconstruct the unknown five-quantum entangled state and the unknown three-quantum entangled state.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] A device authentication module based on quantum principles is used to implement identity authentication between IoT devices without the intervention of a third party, thereby enhancing the security of communications, ensuring that only legitimate devices can access and interact, and effectively preventing unauthorized device intrusion and information leakage; no third-party controller participation is required, thereby reducing interference and complexity in communications, which not only reduces the trust issues caused by third-party intervention, but also reduces the complex technologies and algorithms required for detecting and counteracting interference, reducing the complexity and overhead of the IoT security system; by using the product of three Bell states as a bidirectional information transmission module for the quantum channel, the scheme can achieve efficient quantum information transmission. This quantum state-based transmission method has higher transmission efficiency and lower interference than traditional communication methods.

[0028] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the embodiments of the present invention are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0030] Figure 1 is an overall flow chart of the authentication communication scheme in the embodiment;

[0031] Figure 2 is a flow chart of transmission particle deformation in an embodiment;

[0032] Figure 3 is an overall flow chart of the transmission module in the embodiment;

[0033] Figure 4 is a flow chart of transport particle reconstruction in an embodiment. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0035] Please refer to Figure 1The embodiment of the present invention provides a bidirectional quantum secure communication method for the Internet of Things, in which the two communicating parties are defined as Alice and Bob, and they use a device authentication module based on quantum principles to verify each other's identities, and then use a bidirectional information transmission module that does not require the participation of a third party to communicate; wherein the bidirectional information transmission module uses the product of three Bell states as a quantum channel.

[0036] 1. About the device authentication module

[0037] In the device authentication module based on quantum principle in this embodiment, the polarization state of a single photon is in a two-dimensional Hilbert space, in which there are multiple orthogonal bases. Generally, we only use two orthogonal bases, namely the linear polarization base ⊕ composed of the vertical polarization state |90°> and the horizontal polarization state |0°>, and the circular polarization base ⊕ composed of |45°> and |135°>.

[0038] According to Heisenberg's uncertainty principle and quantum no-cloning principle, the measurement results of these two bases are incompatible. The quantum alphabet agreed upon by Alice and Bob is shown in Table 1.

[0039] Table 1

[0040]

[0041] First, Alice and Bob share a 2n-bit binary identity authentication string ID = [p1, p2, ... p n ,p n+1 ,...p 2n ], where each bit has a value of 0 or 1. The first n bits of the binary authentication string are used by Alice to detect Bob's identity, and the last n bits are used by Bob to detect Alice's identity.

[0042] (1) Alice verifies Bob's identity, which includes the following steps:

[0043] S11: Alice selects a physical noise source to generate an n-bit binary random sequence as the original selected bit string S a ;

[0044] S12: Alice takes the first n bits of the binary identity authentication string ID1 = [p1, p2, ... p n ] as the base bit string, and S a Each bit of the data is converted into a single photon polarization state, and the resulting photon state is then sent to Bob;

[0045] S13: Bob authenticates the first n bits of the binary identity string ID1=[p1,p2,...pn ] Select the same measurement basis as Alice used, measure the received photon state, and obtain the binary random sequence S b , and send it to Alice;

[0046] S14: Alice sends the original selected bit string S a The binary random sequence S measured by Bob b Make a comparison, estimate the error, and compare the error with the security threshold. If the error is less than or equal to the pre-set security threshold, Alice believes Bob's identity and the authentication scheme continues. If the error exceeds the security threshold, it means that Bob's identity is in doubt or the communication has been eavesdropped, and Alice needs to end the communication.

[0047] (2) Bob verifies Alice’s identity, which includes the following steps:

[0048] S21: Alice takes the last n digits of the binary identity authentication string ID2 = [p n+1 ,p n+2 ,...p 2n ] as a selection bit string;

[0049] S22: Alice uses a physical noise source to generate an n-bit binary random sequence T a As the base bit value, each bit of ID2 is converted into a single photon polarization state and then sent to Bob;

[0050] S23: Bob uses a physical noise source to generate an n-bit binary random sequence T b As the basis bit value sequence, the measurement basis is selected according to this sequence to measure the polarization states of the n single photons transmitted by Alice, the measurement results are compared with ID2, the positions where the measurement results do not match ID2 are recorded and sent to Alice;

[0051] S24: Alice will not match the corresponding T in the position a The value is sent to Bob, who detects the T at the mismatched position. b Is the value the same as T sent by Alice? a The values ​​are the same. If they are different, Bob believes Alice's identity. If they are the same, Alice's identity is in doubt or the communication has been eavesdropped, and Bob needs to end the communication.

[0052] (3) Next, we will deduce whether the above two-way identity authentication strategy can effectively prevent forged identity attacks. Here we assume that n = 6, and the two communicating parties share a twelve-bit binary identity authentication string ID = (011101010110) before communication. The specific content of this ID string is only known to the two communicating parties. At this time, the eavesdropper Eve attempts to pretend to be the communicating party to communicate with the other party, which can be divided into the following two situations:

[0053] 1) Eve pretends to be Bob to gain Alice’s trust

[0054] Alice first uses a physical noise source to generate a six-bit binary random sequence as the selected bit string S a , here we assume that S a =(101101), and then Alice will take the first n bits of the ID string as the selection base bit value string ID1=(011101).

[0055] According to the contents of the two strings, Alice generates a photon polarization state sequence [|0°>|45°>|135°>|135°>|90°>|135°>] and sends it to Eve for identity authentication. At this time, Eve receives the n-bit single photon polarization state sent by Alice. At this time, Eve does not know the specific content of ID1, so she can only randomly select the measurement basis. Assume that Eve uses the randomly selected basis bit string ID e =(101111), at this time Eve will have a probability of nearly 50% to choose the wrong measurement basis, thus obtaining the wrong character. After the measurement, Eve will obtain the binary random sequence S e =(011111) and send it to Alice.

[0056] Alice vs. S a and S e Ideally, the error should be 0, but by comparing it with the sequence sent by Eve, it is found that the error is about 50%. Such a high error is obviously unacceptable. At this time, Alice discovers Eve's disguised eavesdropping behavior and will actively end the communication.

[0057] 2) Eve pretends to be Alice to gain Bob’s trust

[0058] First, Eve needs to take the last n bits of the ID string as the selected bit value string, but Eve does not know the content of the ID string, so she can only use a random string ID. e , we assume that ID e =(111001). Eve then selects a physical noise source to generate a selected base bit string T e , we assume that T e =(001011).

[0059] According to the contents of the two strings, Eve generates a photon polarization state sequence [|0°>|0°>|135°>|90°>|45°>|135°>] and sends it to Bob for identity authentication. After receiving the photon state sequence, Bob uses a physical noise source to generate an n-bit random sequence T b =(110110) is used as the selected base bit value sequence, and after measuring the polarization states of the n single photons transmitted by Alice, the binary sequence [000100] can be obtained.

[0060] Bob compares the measurement result with ID2 and records that the positions that do not match ID2 are the second and fifth positions. e The value of the corresponding position in is sent over. Since Eve does not have an ID string, it can only return T e The value of the corresponding position is [0,1], and the value of the corresponding position of the string held by Bob is [1,1]. If the values ​​are the same, Bob will discover Eve's disguised eavesdropping behavior and will actively end the communication.

[0061] In summary, the two-way identity authentication strategy proposed in this embodiment can effectively prevent forged identity attacks.

[0062] 2. About the two-way information transmission module

[0063] In the bidirectional information transmission module used in this embodiment, Alice and Bob share a six-qubit channel, which is the product of three Bell states, as shown in the following formula: Alice has qubits 1, 3, and 6, and Bob has qubits 2, 4, and 5.

[0064]

[0065] In the above formula, Ψ is the quantum channel shared by Alice and Bob.

[0066] Alice wants to send an unknown five-qubit entangled state to Bob, as shown in the following formula

[0067]

[0068] In the above formula, τ A That is the five-qubit entangled state that Alice wants to send, a1a2a3a4a5 is the number of the five particles, α0α1α2α3 is a complex coefficient and satisfies the normalization equation

[0069] |α0| 2 +|α1| 2 +|α2| 2 +|α3| 2 =1

[0070] At the same time, Bob also wants to send an unknown three-qubit entangled state to Alice, as shown below.

[0071]

[0072] In the above formula, τ B That is the three-qubit entangled state that Bob wants to send, b1b2b3 are the numbers of the five particles, β0β1 are complex coefficients and satisfy the normalization equation.

[0073] The implementation steps of the two-way information transmission module are as follows:

[0074] S31: The two communicating parties first transform the unknown quantum entangled states they hold, converting them into pure arbitrary states for transmission, thereby improving the inherent efficiency of the scheme. Based on the pure arbitrary state, the system state can be obtained, as follows:

[0075] Before Alice and Bob can communicate, they need to do some preparations for sending particles. For details, see Figure 2 .

[0076] Alice performs a swap gate operation on (a2, a4), and then performs a CNOT operation on the quantum bit pairs (a1, a3), (a1, a2), and (a1, a5), where a1 is the control quantum bit and a3a2a5 are the target quantum bits. Convert to and As shown in the following formula:

[0077]

[0078] In the above formula, α0α1α2α3 are complex coefficients and satisfy the normalization equation |α0| 2 +|α1| 2 +|α2| 2 +|α3| 2 =1.

[0079] Bob performs a CNOT operation on the qubit pairs (b1, b2) and (b1, b3), using qubit b1 as the control qubit and qubits b2 and b3 as target qubits. Convert to and As shown in the following formula:

[0080]

[0081] In the above formula, β0β1 are complex coefficients and satisfy the normalization equation |β0| 2 +|β1| 2 =1.

[0082] After the deformation operation is completed, only the first and fourth particles of the five-quantum entangled state carry information, and only the first particle of the three-quantum entangled state carries information. At this time, we only need to entangle these three particles with the quantum channel to form a system state. The initial state of the entire system is expressed as:

[0083]

[0084] In the above formula, φ is the initial state of the system, Ψ is the quantum channel, τ A are two free particles to be sent, τ B is a free single particle to be sent, and the whole transmission process is shown in Figure 3 .

[0085] Alice applies CNOT operation to particle pairs (a1, 1) and (a4, 3) respectively, where a1 and a4 qubits are control bits, and qubits 1 and qubits 3 are target bits; Bob applies CNOT operation to particle pair (b1, 2), where qubit b1 is the control bit and qubit 2 is the target bit; finally, Swap gate is applied to a4b1. After the operation is completed, the system state becomes:

[0086]

[0087] S32: Alice and Bob perform Z-basis single quantum measurements on qubits 1, 3, and 2. After the measurement is completed, the remaining qubits will collapse into one of the eight collapsed states with the same probability.

[0088] S33: The two communicating parties inform each other of their measurement results in step S32 through the classical channel. The two communicating parties apply unitary operations to the remaining quantum bits in the system state to obtain the target collapsed state among the eight collapsed states, as follows:

[0089] Alice and Bob inform each other of their measurement results through the classical channel, and both parties apply appropriate unitary operations to qubits 4, 5, and 6. The unitary operations performed by Alice and Bob are as follows:

[0090] I=|0><0|+|1><1|σ x =|0><1|+|1><0|σ z =|0><0|-|1><1|

[0091] In the above formula, I is a non-changing operation, σ x is a unitary operation based on the X basis, σ z It is a unitary operation based on the Z basis. After the appropriate unitary operation is completed, the remaining entangled quantum bits will be transformed into the form shown in the following formula, that is, the target collapsed state is obtained:

[0092] α0β0|000000>+α0β1|001001>+α1β0|010010>+α1β1|011011>

[0093] +α2β0|100100>+α2β1|101101>+α3β0|110110>+α3β1|111111>

[0094] S34: The communicating parties perform single quantum measurement on the basis X on the particle carrying information in the target collapsed state. After the measurement is completed, the remaining qubits will collapse with the same probability, as follows:

[0095] Alice and Bob perform single quantum measurements on the information-carrying particles a1, a4, and b1 in the X basis, respectively. The measurement results are as follows:

[0096]

[0097]

[0098] S35: The two communicating parties inform each other of their measurement results in step S34 through the classical channel. The two communicating parties apply unitary operations to the remaining quantum bits after collapse to obtain the target state, as follows:

[0099] After the measurement in step S34 is completed, the remaining qubits will collapse with the same probability. Alice and Bob inform each other of their measurement results through the classical channel. Both parties apply appropriate unitary operations to qubits 4, 5, and 6. After the appropriate unitary transformation is completed, all remaining entangled qubits will be transformed into the target state:

[0100]

[0101] S36: The communicating parties introduce auxiliary qubits and perform the deformation operation in reverse to reconstruct the unknown five-quantum entangled state and the unknown three-quantum entangled state, as follows:

[0102] Alice introduces two auxiliary qubits for the collapsed qubit 6 |00> cd ; Bob introduces three auxiliary qubits for the collapsed qubits 4 and 5 |000> efg , Alice then performs a CNOT operation on the particle pairs (6,c) and (6,d), where qubit 6 is the control bit and qubits c and d are the target bits; Bob performs a swap gate operation on 5 and f, and then performs a CNOT operation on the particle pairs (4,f), (4,e) and (4,g), where qubit 4 is the control bit and qubits f, e and g are the target bits. The results are as follows:

[0103] |χ> 6cd =(β0|000>+β1|111>) 6cd

[0104] |χ> 4fe5g =(α0|00000>+α1|00010>+α2|11101>+α3|11111>) 4fe5g

[0105] It can be proved that this embodiment can realize bidirectional quantum teleportation and reconstruct unknown five-quantum entangled states and unknown three-quantum entangled states. The transmission particle reconstruction process is as follows: Figure 4 shown.

[0106] Communication efficiency analysis, in the quantum communication scheme of this embodiment, by using the formula To calculate the transmission efficiency of the protocol, where q c represents the number of transmitted quantum states, q s represents the consumption of quantum resources, q j Representing the consumption of classical resources, the efficiency of the protocol calculated based on this scheme is 36.3%, which is higher than that of most remote quantum state preparation protocols.

[0107] This example solution was experimentally verified using the IBM Quantum Experience platform and Qiskit quantum programming language. The results show that this example solution can successfully achieve asymmetric bidirectional transmission of unknown quantum states under ideal conditions. Security analysis shows that this example solution can effectively prevent forged identity attacks, interception replay attacks, and interception measurement attacks, ensuring the confidentiality and integrity of quantum communications in the Internet of Things.

[0108] The combination of quantum communication solutions and IoT devices in this example opens up new possibilities for secure, efficient and reliable communications in various application scenarios.

[0109] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A two-way quantum secure communication method for the Internet of Things, characterized in that: The communicating parties use a device authentication module based on quantum principles to verify each other's identities, and then use a two-way information transmission module that does not require the participation of a third party to communicate; wherein the two-way information transmission module uses the product of three Bell states as a quantum channel.

2. The Internet of Things bidirectional quantum secure communication method according to claim 1, characterized in that: During the device authentication process of the device authentication module, the communicating parties share a 2n-bit binary identity authentication string, the first n bits of which are used by the first communicating party to detect the identity of the second communicating party, and the last n bits are used by the second communicating party to detect the identity of the first communicating party.

3. The Internet of Things bidirectional quantum secure communication method according to claim 2, characterized in that: The method for a first communication party to detect the identity of a second communication party comprises the following steps: S11: The first communication party generates an n-bit binary random sequence as an original selected bit string; S12: The first communication party takes the first n bits of the binary identity authentication string as a selected base bit string, converts each bit of the original selected state bit string into a single photon polarization state, and then sends the obtained photon state to the second communication party; S13: The second communication party selects a measurement basis according to the first n bits of the binary identity authentication string, measures the received photon state, obtains a binary random sequence, and sends it to the first communication party; S14: The first communication party compares the original selected bit string with the binary random sequence measured by the second communication party to estimate the error. If the error is less than or equal to the security threshold, the first communication party believes the identity of the second communication party. If the error exceeds the security threshold, it means that the identity of the second communication party is in doubt or the communication has been eavesdropped, and the first communication party needs to end the communication.

4. The Internet of Things bidirectional quantum secure communication method according to claim 2, characterized in that: The method for the second communication party to detect the identity of the first communication party comprises the following steps: S21: The first communication party takes the last n bits of the binary identity authentication string as a selected bit string; S22: The first communication party generates an n-bit binary random sequence T a As the selected base bit value, each bit of the selected state bit string is converted into a single photon polarization state, and then sent to the second communication party; S23: The second communication party generates an n-bit binary random sequence T b As the selected base bit value sequence, measure the polarization states of n single photons transmitted by the first communication party, compare the measurement results with the selected state bit string, record the mismatching positions between the measurement results and the selected state bit string, and send them to the first communication party; S24: The first communication party will not match the corresponding T a The value is sent to the second communication party, and the second communication party detects T at the corresponding position b Whether the value is the same as the Ta value sent by the first communication party, if different, the second communication party believes the identity of the first communication party, if the same, the identity of the first communication party is in doubt or the communication has been eavesdropped, and the second communication party needs to end the communication.

5. The Internet of Things bidirectional quantum secure communication method according to claim 3 or 4, characterized in that: A physical noise source is selected to generate a binary random sequence.

6. The Internet of Things bidirectional quantum secure communication method according to claim 2, characterized in that: The method for communicating using the two-way information transmission module comprises the following steps: S31: The communicating parties perform deformation operations on the unknown quantum entangled states they hold, and convert them into pure arbitrary states for transmission, and obtain the system state based on the pure arbitrary states; S32: The communicating parties perform Z-basis single quantum measurement on the quantum bits corresponding to the particles carrying information in the system state; S33: The two communicating parties inform each other of their measurement results in step S32 through the classical channel, and the two communicating parties apply unitary operations to the remaining quantum bits in the system state to obtain the target collapsed state; S34: The communicating parties perform single quantum measurement on the X basis on the particle carrying information in the target collapsed state; S35: The two communicating parties inform each other of their measurement results in step S34 through the classical channel, and the two communicating parties apply unitary operations to the remaining quantum bits after collapse to obtain the target state; S36: The communicating parties introduce auxiliary quantum bits and perform the deformation operation in reverse to reconstruct the unknown five-quantum entangled state and the unknown three-quantum entangled state.

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