Group conference-oriented event-triggered quantum key update method

Abstract

The application discloses a group conference-oriented event-triggered quantum key update method, belongs to the technical field of quantum communication, is executed by a third party, and comprises the following steps: obtaining a corrected weight according to a basic priority score and a QKD network load; calculating a final priority score based on an event initial priority and the corrected weight, determining a key generation level according to a preset threshold, generating a key generation start instruction, setting a communication parameter configuration rule, and initializing a node state table; performing joining compensation calculation to obtain an updated global mask phase according to a quantum state disclosed by a participant and a node joining request, performing offline compensation calculation according to an offline state of a node in the node state table to obtain a completed cumulative phase; and generating a new key based on a final key disclosed by a new participant node and updating the final key by using the new key. The application solves the problems that the existing group key update needs to interrupt a conference, consumes high resources and cannot adapt to network load.

Description

Technical Field

[0001] This invention relates to an event-triggered quantum key update method for group conferences, belonging to the field of quantum communication technology. Background Technology

[0002] Quantum Key Distribution (QKD) technology, with its unconditional security based on the fundamental principles of quantum mechanics, has become one of the core means to ensure the security of group conference communication. In group conference scenarios, multiple participants need to share the same session key to achieve secure communication, and the periodic updating of the key and the timely refresh when members change are key links to ensure forward and backward security. Existing group quantum key update schemes are mainly divided into two categories: one is a periodic update scheme based on the Quantum Key Agreement (QKA) protocol, in which all participants generate a new group key through multiple rounds of quantum state transmission and measurement negotiation; the other is a centralized distribution scheme based on trusted relays or key management centers, in which a central node uniformly generates new keys and distributes them to each participant. In addition, for scenarios where members join or leave, some protocols have designed incremental update mechanisms based on group key matrices or key trees, attempting to replace global key renegotiation with local recomputation to reduce update overhead.

[0003] However, the existing solutions described above have significant drawbacks in practical group conferencing applications. First, whether it's a periodic update or an update triggered by member changes, the existing protocols generally require interrupting the current conference communication. All participants must pause data transmission to accommodate the key renegotiation process, leading to noticeable lag or even brief interruptions, severely impacting the user experience. Second, the resource consumption of the existing solutions is strongly correlated with the group size. When a member joins or leaves, all online participants often need to re-execute the complete quantum state preparation, transmission, and measurement process. The overhead of qubits and classical communication increases linearly with the number of members. When the group size is large or member changes are frequent, the resource overhead expands significantly. Third, the existing solutions do not consider the impact of the actual load of the QKD network on the key update strategy. The key generation level and communication parameter configuration remain fixed, making it impossible to dynamically adjust parameters such as the decoy state ratio and phase selection accuracy according to network activity levels. This results in a dual dilemma of wasted resources when the network is idle and update delays when it is busy, leading to insufficient overall system efficiency and practicality. Summary of the Invention

[0004] The purpose of this invention is to provide an event-triggered quantum key update method for group conferences. By using event-driven weighted evaluation and phase compensation for smooth transition, it solves the problems of existing group key updates requiring conference interruption, high resource consumption, and inability to adapt to network load.

[0005] To solve the above-mentioned technical problems, the present invention is implemented using the following technical solution.

[0006] In a first aspect, the present invention provides an event-triggered quantum key update method for group conferences, executed by a third party, comprising:

[0007] Based on the initial priority and weight of the event, a weighted fusion model is used to calculate the basic priority score;

[0008] The correction weight is obtained based on the basic priority score and the QKD network load correction event weight;

[0009] Based on the initial priority and adjusted weights of the events, a weighted fusion model is used to calculate the final priority score;

[0010] Based on the final priority score, the key generation level is determined according to a preset threshold, and a key generation start command is generated.

[0011] The startup command generates a key to set up communication parameter configuration rules and initializes the node status table.

[0012] Based on the quantum states disclosed by the participants and the node joining requests, the joining compensation calculation is performed to obtain the updated global mask phase;

[0013] Based on the updated global mask phase and the node offline status in the node status table, perform offline compensation calculation to obtain the completed cumulative phase and publish it.

[0014] A new key is generated based on the final key disclosed by the new participating node, and the final key is updated using the new key.

[0015] Furthermore, the basic priority score is expressed as:

[0016] ;

[0017] In the formula, Indicates the basic priority score. Indicates the initial priority. Represents the association weight, where, This indicates a preset high-priority event. This indicates a preset medium-priority event. This indicates a preset low-priority event. This indicates that the incident is a security incident. This indicates that the event is a resource event. This indicates that the event is a network event. This indicates that the event is a user event;

[0018] The final priority score is expressed as follows:

[0019] ;

[0020] In the formula, This indicates the final priority score. This indicates the adjusted weights, where, .

[0021] Furthermore, based on the final priority score, the key generation level is determined according to a preset threshold to generate a key generation initiation command, including:

[0022] If the final priority score is greater than the preset threshold, the key generation level is determined based on the adjusted weight to generate the key generation start command.

[0023] If the final priority score is less than or equal to the preset threshold, the key generation level is determined based on the associated weight to generate the key generation start command.

[0024] Furthermore, the node state table is represented as follows:

[0025] ;

[0026] In the formula, Represents the node status table. Indicates the first The initial priority of each node, Indicates the first The online status identifier of each node, where, Indicates the first Each node is online. Indicates the first One node is offline. Indicates the first The quantum state modulation phase value of each node.

[0027] Furthermore, based on the quantum states disclosed by the participants and the node joining requests, a joining compensation calculation is performed to obtain the updated global mask phase, including:

[0028] The quantum state disclosed by the participating party is transmitted to the new participating node corresponding to the node joining request, and the new participating node selects a phase value from a preset phase set and applies modulation to obtain the node modulation phase; wherein, the preset phase set only includes Discrete angle values ​​within the range;

[0029] The node modulation phase is represented as:

[0030] ;

[0031] In the formula, Indicates the node modulation phase. Indicates a preset phase set;

[0032] Select the private mask corresponding to the new participating node itself, apply the private mask to the modulation phase of the node, and perform calculation to obtain the new node mask phase;

[0033] The new node mask phase is represented as:

[0034] ;

[0035] In the formula, Indicates the phase of the new node mask. This represents the private mask corresponding to the new node itself;

[0036] Obtain the new node mask phase sent by the new participating node to the third party through the encrypted classic channel, and perform a modulo addition calculation with the current global mask phase to obtain the updated global mask phase;

[0037] The updated global mask phase is represented as:

[0038] ;

[0039] In the formula, This indicates the updated global mask phase. Indicates the current global mask phase. This represents the modulo addition calculation function.

[0040] Furthermore, based on the updated global mask phase and the node offline status in the node status table, offline compensation calculation is performed to obtain the completed cumulative phase, which is then made public, including:

[0041] Based on the offline status of nodes in the node status table, the temporary global mask phase is obtained by subtracting the offline node mask phase corresponding to the exiting participant from the updated global mask phase.

[0042] The temporary global mask is represented as follows:

[0043] ;

[0044] In the formula, Indicates the temporary global mask phase. This indicates the offline node mask phase corresponding to the participant who has withdrawn.

[0045] Based on the temporary global mask phase, select an online legitimate participant, and have the online legitimate participant select a new private mask to update the local private mask;

[0046] Calculate the difference between the new private mask and the local private mask to obtain the mask difference;

[0047] The mask difference is expressed as:

[0048] ;

[0049] In the formula, Indicates the mask difference. This represents the new private mask chosen by legitimate online participants. A local private mask representing a legitimate online participant.

[0050] The mask difference is modulo-added with the temporary global mask phase to obtain the padded cumulative phase, which is then made public.

[0051] The completed accumulated phase is represented as:

[0052] ;

[0053] In the formula, This indicates the cumulative phase after completion.

[0054] Secondly, the present invention provides an event-triggered quantum key update method for group conferences, executed by the participants, comprising:

[0055] The quantum communication parameters are obtained by setting the communication parameters based on the final priority score.

[0056] Based on the quantum communication parameters, the quantum state preparation and distribution process is executed to obtain the transmitted quantum state and make it public;

[0057] Based on the final key published by the new participating node, a new key is generated through a simplified process, and the final key is updated using the new key.

[0058] Furthermore, communication parameters are set based on the final priority score to obtain quantum communication parameters, including:

[0059] The key generation level result is obtained based on the final priority score and determined according to a preset threshold. The key generation level result includes a preset high priority and a preset low priority.

[0060] Based on the key generation level results, the fiber optic channel transmission distance between nodes is obtained and calculated to obtain the quantum error rate security threshold.

[0061] When the key generation level result is a preset high priority, the first decoy state ratio is set, and the quantum error rate security threshold is expressed as:

[0062] ;

[0063] In the formula, This represents the quantum error rate security threshold. This represents the bit error rate constant of the basic equipment. Represents the linear attenuation coefficient of optical fiber. Indicates the fiber optic channel transmission distance between nodes;

[0064] Based on the quantum error rate security threshold and the key generation level result, decoy state configuration processing is performed according to the first decoy state ratio to obtain quantum communication parameters;

[0065] When the key generation level result is a preset low priority, a second decoy state ratio is set, and the quantum error rate security threshold is set to a preset constant.

[0066] Based on the quantum error rate security threshold and the key generation level result, decoy state configuration processing is performed according to the second decoy state ratio to obtain quantum communication parameters;

[0067] Wherein, the ratio of the first deceptive state is less than the ratio of the second deceptive state.

[0068] Furthermore, based on the quantum communication parameters, a quantum state preparation and distribution process is executed to obtain and disclose the transmitted quantum state, including:

[0069] According to the quantum communication parameters, the initial participant generates a normalized single-photon initial state under the corresponding priority, and transmits it to the subsequent participating nodes in the order of the preset nodes to obtain the single-photon transmission quantum state.

[0070] The single-photon transmission quantum state is represented as:

[0071] ;

[0072] In the formula, Indicates a single-photon transport quantum state, subscript Indicates the initial state. and Let represent the orthogonal basis vectors of the horizontally polarized state and the vertically polarized state of the single-photon transport quantum state, respectively. Represents the probability amplitude coefficient. Represents the superposition of quantum states;

[0073] Based on the single-photon transmission quantum state, each participating node selects a local selection phase according to the phase selection range corresponding to the priority, and applies Pauli-Z operator modulation to the single-photon transmission quantum state and superimposes its own private mask to calculate the quantum state modulation phase value. The quantum state modulation phase value is then sent to a third party for public disclosure through an encrypted classical channel as the quantum state after transmission is completed.

[0074] Among them, the The quantum state modulation phase value of each node is expressed as:

[0075] ;

[0076] In the formula, Indicates the first The quantum state modulation phase value of each node, Indicates the first Local selection phase of each node Indicates the first The private mask of each node;

[0077] Wherein, when the key generation level result is a preset high priority, the selection range of the local selection phase is: ;

[0078] When the key generation level result is a preset low priority, the selection range of the local selection phase is: .

[0079] Thirdly, the present invention provides an event-triggered quantum key update method for group meetings, executed by a newly participating node, comprising:

[0080] Based on the quantum state and node joining request transmitted by the participants, select the local private phase and private mask, calculate the new node mask phase, and send the new node mask phase to the third party;

[0081] Based on the completed cumulative phase disclosed by a third party, eavesdropping detection is performed and compared with a preset QBER threshold to obtain the channel security determination result.

[0082] Based on the channel security determination result, the execution of quantum state measurement is terminated and the measurement basis and angle parameters are disclosed, thus obtaining the quantum state measurement result and the disclosed angle set;

[0083] Based on the quantum state measurement results and the publicly available angle set, the 256-bit original key is decoded.

[0084] Based on the 256-bit original key and the final priority score, block error correction is performed according to the preset priority rules to obtain the corrected key;

[0085] Based on the corrected key and the final priority score, privacy amplification calculation is performed according to the preset priority rules to obtain the final key and make it public;

[0086] A new key is generated based on the final key, and the final key is updated using the new key.

[0087] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0088] 1. This invention calculates a basic priority score by weighting and fusing the initial priority of events with event weights, and then recalculates the final priority score after adjusting the event weights based on the QKD network load. This achieves a refined and dynamic evaluation of the key update triggering conditions, avoiding the resource waste and communication interruption caused by performing a complete key update process for all events. Simultaneously, by determining the key generation level based on the final priority score and generating a key generation start command, key updates are triggered only under necessary conditions, reducing unnecessary updates and lowering the frequency of group meeting interruptions. Furthermore, by performing join compensation calculations based on the quantum states disclosed by participants and node join requests to update the global mask phase, and performing offline compensation calculations based on the global mask phase and node offline status to obtain the completed cumulative phase, a smooth key transition can be achieved through phase compensation without interrupting the meeting when members join or leave. This avoids the high resource consumption caused by the need for all participants to re-execute the quantum state preparation, transmission, and measurement processes when members change, as required by existing schemes. At the same time, through the initialization of communication parameter configuration rules and node state tables, dynamic adaptation of the key update process to the QKD network load status is ensured, improving the efficiency and practicality of quantum key updates in group meetings.

[0089] 2. This invention obtains quantum communication parameters by having participants set communication parameters based on their final priority scores. This achieves dynamic matching between communication parameters, event priorities, and the QKD network load during key updates, avoiding resource waste or performance issues caused by fixed communication parameter configurations. Simultaneously, by executing the quantum state preparation and distribution process according to the quantum communication parameters and publicly disclosing the transmitted quantum state, participants can collaboratively complete the key update process based on unified quantum state information, ensuring consistency and synchronization of key updates across multiple parties in group meetings. Furthermore, by generating a new key based on the final key disclosed by the new participating node through a simplified process and updating the final key, participants can directly complete key switching without additional key negotiation with third parties or other participants after the new key is generated. This further shortens communication interruption time during key updates and improves the efficiency of key updates in group meetings.

[0090] 3. This invention obtains an updated global mask phase by performing a join compensation calculation based on the quantum state transmitted by the participants and the node join request. This allows new participating nodes to seamlessly join the existing key distribution system without interrupting the group meeting, avoiding the communication interruption and resource overhead caused by the requirement for all participants to re-execute the complete key negotiation process when a new member joins in the existing scheme. Simultaneously, by performing eavesdropping detection based on the supplemented accumulated phase disclosed by a third party and comparing it with a preset QBER threshold to obtain the channel security determination result, channel security verification is completed before key generation, ensuring the security of the key distribution process and avoiding the waste of computational resources caused by performing subsequent key generation processes under insecure channel conditions. Furthermore, by performing quantum state measurements based on the channel security determination results and publicly disclosing the measurement basis and angle parameters, and combining this with decoding to obtain a 256-bit original key, block error correction and privacy amplification calculations are performed sequentially according to the preset priority rules corresponding to the final priority score. This allows the computational complexity of error correction and privacy amplification to dynamically adapt to the key update priority. Low-priority events are simplified to reduce computational overhead, while high-priority events are enhanced to ensure key security, achieving a balance between security and efficiency. Moreover, by generating a new key based on the final key and updating the final key, new participating nodes maintain key synchronization with other members of the group after key generation, ensuring the continuity and security of group conference communication. Attached Figure Description

[0091] Figure 1 This is a flowchart illustrating an event-triggered quantum key update method for group conferences executed by a third party, as provided in an embodiment of the present invention.

[0092] Figure 2 This is a flowchart illustrating an event-triggered quantum key update method for group meetings, executed by participating parties, provided in an embodiment of the present invention.

[0093] Figure 3 This is a flowchart illustrating an event-triggered quantum key update method for group meetings, executed by a new participating node, provided in an embodiment of the present invention. Detailed Implementation

[0094] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical solution of the present invention, rather than limitations thereof. In the absence of conflict, the embodiments of the present invention and the technical features in the embodiments can be combined with each other.

[0095] Example 1

[0096] like Figure 1As shown, this embodiment introduces an event-triggered quantum key update method for group conferences, executed by a third party, including:

[0097] Step 1: Based on the initial priority and weight of the event, calculate the basic priority score using a weighted fusion model.

[0098] This embodiment calculates the basic priority score based on the initial priority and event weight using a weighted fusion model. By weighting and fusing the initial priority and dynamic event weight, the basic priority score can simultaneously reflect the urgency of the event itself and the importance preference in the current business scenario, thereby providing a quantitative basis for subsequent key update decisions.

[0099] In this embodiment, the basic priority score is represented as:

[0100] ;

[0101] In the formula, Indicates the basic priority score. Indicates the initial priority. Represents the association weight, where, This indicates a preset high-priority event. This indicates a preset medium-priority event. This indicates a preset low-priority event. This indicates that the incident is a security incident. This indicates that the event is a resource event. This indicates that the event is a network event. This indicates that the event is a user event.

[0102] Step 2: Based on the basic priority score and the QKD network load correction event weight, obtain the correction weight.

[0103] This embodiment obtains the correction weight based on the basic priority score and the QKD network load correction event weight. By using the basic priority score as a feedback factor and combining it with the QKD network load to correct the weight, the correction weight can be adaptively adjusted according to the network congestion level, thereby avoiding the aggravation of quantum channel congestion caused by frequent key updates under high load.

[0104] Step 3: Based on the initial priority and adjusted weights of the events, calculate the final priority score using a weighted fusion model.

[0105] This embodiment calculates the final priority score based on the initial priority and the adjusted weights using a weighted fusion model. By re-substituting the adjusted weights into the weighted fusion model for calculation, the final priority score integrates both the inherent attributes of the event and the dynamic state of the network, thereby improving the accuracy of priority assessment in group meeting scenarios.

[0106] In this embodiment, the final priority score is represented as:

[0107] ;

[0108] In the formula, This indicates the final priority score. This indicates the adjusted weights, where, .

[0109] Step 4: Based on the final priority score, determine the key generation level according to the preset threshold, and generate the key generation start command.

[0110] This embodiment determines the key generation level based on the final priority score and a preset threshold, and generates a key generation start command. By classifying the final priority score and the preset threshold into levels and generating corresponding start commands, the triggering time of the key generation operation is precisely matched with the event priority level, thereby avoiding unnecessary key update overhead caused by low-priority events.

[0111] Step 4.1: If the final priority score is greater than the preset threshold, the key generation level is determined according to the adjusted weight to generate the key generation start command.

[0112] Step 4.2: If the final priority score is less than or equal to the preset threshold, the key generation level is determined based on the associated weight to generate the key generation start command.

[0113] Step 5: Generate startup instructions based on the key, set communication parameter configuration rules, and initialize the node status table.

[0114] This embodiment sets communication parameter configuration rules based on the key generation start command and initializes the node state table. By configuring communication parameters and initializing the node state table immediately after key generation is started, subsequent quantum state transmission and phase compensation operations have a unified parameter benchmark and node state record, thereby ensuring the synchronization consistency of each node in the group.

[0115] In this embodiment, the node status table is represented as follows:

[0116] ;

[0117] In the formula, Represents the node status table. Indicates the first The initial priority of each node, Indicates the first The online status identifier of each node, where, Indicates the first Each node is online. Indicates the first One node is offline. Indicates the first The quantum state modulation phase value of each node.

[0118] Step 6: Based on the quantum states disclosed by the participants and the node joining requests, perform joining compensation calculations to obtain the updated global mask phase.

[0119] In this embodiment, based on the quantum state disclosed by the participants and the node joining request, a joining compensation calculation is performed to obtain the updated global mask phase. By incorporating the phase offset of the newly joined node into the update iteration of the global mask phase, the updated global mask phase can compensate for the group phase mismatch caused by the node joining, thereby maintaining the group phase consistency and avoiding the redistribution of the original quantum state.

[0120] Step 6.1: Transmit the quantum state disclosed by the participant to the new participating node corresponding to the node joining request, and instruct the new participating node to select a phase value from the preset phase set and apply modulation to obtain the node modulation phase.

[0121] In this embodiment, the preset phase set only includes Discrete angle values ​​within the range; the node modulation phase is expressed as:

[0122] ;

[0123] In the formula, Indicates the node modulation phase. Indicates a preset phase set;

[0124] Step 6.2: Select the private mask corresponding to the new participating node itself, apply the private mask to the modulation phase of the node, and perform calculation to obtain the new node mask phase;

[0125] In this embodiment, the new node mask phase is represented as:

[0126] ;

[0127] In the formula, Indicates the phase of the new node mask. This represents the private mask corresponding to the new node itself;

[0128] Step 6.3: Obtain the new node mask phase sent by the new participating node to the third party through the encrypted classic channel, and perform modulo addition calculation with the current global mask phase to obtain the updated global mask phase;

[0129] In this embodiment, the updated global mask phase is represented as:

[0130] ;

[0131] In the formula, This indicates the updated global mask phase. Indicates the current global mask phase. This represents the modulo addition calculation function.

[0132] Step 7: Based on the updated global mask phase and the node offline status in the node status table, perform offline compensation calculation to obtain the completed cumulative phase and publish it.

[0133] This embodiment performs offline compensation calculations based on the updated global mask phase and the offline status of nodes in the node status table to obtain the completed cumulative phase and publishes it. By using the offline status in the node status table as the triggering condition for compensation calculation, the completed cumulative phase can cover the phase information missing by offline nodes, thereby ensuring that the published cumulative phase completely contains the historical interference data of all participating nodes.

[0134] Step 7.1: Based on the offline status of the nodes in the node status table, subtract the offline node mask phase corresponding to the exiting participant from the updated global mask phase to obtain the temporary global mask phase;

[0135] In this embodiment, the temporary global mask is represented as:

[0136] ;

[0137] In the formula, Indicates the temporary global mask phase. This indicates the offline node mask phase corresponding to the participant who has withdrawn.

[0138] Step 7.2: Select an online legitimate participant based on the temporary global mask phase, and have the online legitimate participant select a new private mask to update the local private mask;

[0139] Step 7.3: Calculate the difference between the new private mask and the local private mask to obtain the mask difference;

[0140] In this embodiment, the mask difference is represented as:

[0141] ;

[0142] In the formula, Indicates the mask difference. This represents the new private mask chosen by legitimate online participants. A local private mask representing a legitimate online participant.

[0143] Step 7.4: Perform a modulo addition calculation on the mask difference and the temporary global mask phase to obtain the completed cumulative phase and publish it.

[0144] In this embodiment, the completed accumulated phase is represented as:

[0145] ;

[0146] In the formula, This indicates the cumulative phase after completion.

[0147] Step 8: Generate a new key based on the final key published by the new participating node, and update the final key with the new key.

[0148] This embodiment generates a new key based on the final key published by the new participating node, and updates the final key with the new key. By using the new key as the immediate working key for subsequent group communication and replacing the original final key, the updated key is bound to the real-time state of the quantum channel, thereby avoiding the accumulation of security risks caused by using the same final key for a long time.

[0149] Example 2

[0150] Based on the same inventive concept as Embodiment 1, such as Figure 2 As shown, this embodiment introduces an event-triggered quantum key update method for group meetings, executed by the participants, including:

[0151] Step 1: Set the communication parameters based on the final priority score to obtain the quantum communication parameters.

[0152] This embodiment sets communication parameters based on the final priority score to obtain quantum communication parameters. By using the final priority score as the basis for configuring communication parameters, the light intensity, pulse frequency, and encoding method in the quantum communication parameters are matched with the priority level of the current event. This ensures the communication quality of high-priority events while preventing low-priority events from occupying excessive quantum channel resources.

[0153] Step 1.1: Obtain the key generation level result determined according to a preset threshold based on the final priority score. The key generation level result includes a preset high priority and a preset low priority.

[0154] Step 1.2: Obtain the fiber optic channel transmission distance between nodes based on the key generation level result and calculate it to obtain the quantum error rate security threshold.

[0155] Step 1.2.1: When the key generation level result is a preset high priority, set the first decoy state ratio. The quantum error rate security threshold is expressed as:

[0156] ;

[0157] In the formula, This represents the quantum error rate security threshold. This represents the bit error rate constant of the basic equipment. Represents the linear attenuation coefficient of optical fiber. This indicates the transmission distance of the fiber optic channel between nodes.

[0158] Step 1.2.2: Based on the quantum error rate security threshold and the key generation level result, perform decoy state configuration processing according to the first decoy state ratio to obtain quantum communication parameters.

[0159] Step 1.2.3: When the key generation level result is a preset low priority, set the second decoy state ratio and set the quantum error rate security threshold to a preset constant.

[0160] Step 1.2.4: Based on the quantum error rate security threshold and the key generation level result, perform decoy state configuration processing according to the second decoy state ratio to obtain quantum communication parameters.

[0161] In this embodiment, the ratio of the first decoy state is less than the ratio of the second decoy state. In this embodiment, the ratio of the first decoy state is set to 10:1 and the ratio of the second decoy state is set to 3:1.

[0162] Step 2: Based on the quantum communication parameters, execute the quantum state preparation and distribution process to obtain the transmitted quantum state and make it public.

[0163] This embodiment executes a quantum state preparation and distribution process based on quantum communication parameters, obtains a quantum state that has been transmitted and publishes it. By performing quantum state preparation and distribution under the set quantum communication parameters, the quantum state that has been transmitted carries encoded information corresponding to the priority level, and publishes the transmission completion status for other nodes to obtain synchronously, thereby ensuring that all participants in the group complete key distribution preparation under the same quantum communication parameter system.

[0164] Step 2.1: According to the quantum communication parameters, the initial participant generates a normalized single-photon initial state under the corresponding priority, and transmits it to each subsequent participating node in the order of the preset nodes to obtain the single-photon transmission quantum state.

[0165] In this embodiment, the single-photon transmission quantum state is represented as:

[0166] ;

[0167] In the formula, Indicates a single-photon transport quantum state, subscript Indicates the initial state. and Let represent the orthogonal basis vectors of the horizontally polarized state and the vertically polarized state, respectively, representing the quantum state of single-photon transmission. Represents the probability amplitude coefficient. Represents the superposition of quantum states;

[0168] Step 2.2: Based on the single-photon transmission quantum state, each participating node selects a local selection phase according to the phase selection range corresponding to the priority, and applies Pauli-Z operator modulation to the single-photon transmission quantum state and superimposes its own private mask to calculate the quantum state modulation phase value. The quantum state modulation phase value is then sent to a third party for public disclosure through an encrypted classical channel as the completed quantum state.

[0169] In this embodiment, the first The quantum state modulation phase value of each node is expressed as:

[0170] ;

[0171] In the formula, Indicates the first The quantum state modulation phase value of each node, Indicates the first Local selection phase of each node Indicates the first The private mask of each node;

[0172] In this embodiment, when the key generation level result is a preset high priority, the selection range of the local selection phase is: When the key generation level result is a preset low priority, the selection range of the local selection phase is: .

[0173] Step 3: Based on the final key published by the new participating node, generate a new key through a simplified process, and update the final key with the new key.

[0174] This embodiment generates a new key based on the final key published by the new participating node through a simplified process, and updates the final key with the new key. By utilizing the final key already published by the new participating node, the complete quantum state measurement and error correction process is skipped, and the simplified process is directly executed to generate a new key. This allows the participants to quickly update the group key without re-executing the complete quantum key distribution protocol, thereby reducing the computational overhead and communication latency in the group key update process.

[0175] Example 3

[0176] Other embodiments are based on the same inventive concept, such as Figure 3 As shown, this embodiment introduces an event-triggered quantum key update method for group meetings, executed by a new participating node, including:

[0177] Step 1: Based on the quantum state and node joining request transmitted by the participants, select the local private phase and private mask, calculate the new node mask phase, and send the new node mask phase to the third party.

[0178] In this embodiment, a new participating node, upon receiving a node joining request, randomly selects a private phase and a private mask locally and calculates its own new node mask phase. This mask phase is then reported to a third party via an encrypted classical channel. The third party incorporates the new node's phase offset into the global mask phase update iteration and publishes it. This step allows the third party to eliminate group phase mismatch caused by node joining through a phase compensation mechanism, thereby maintaining group phase consistency and avoiding the redistribution of the original quantum state. Maintaining group phase consistency while protecting the privacy of the new node's private mask prevents the redistribution of the original quantum state.

[0179] Step 2: Based on the completed cumulative phase disclosed by a third party, perform eavesdropping detection and compare it with the preset QBER threshold to obtain the channel security determination result.

[0180] This embodiment performs eavesdropping detection based on the completed cumulative phase disclosed by a third party and compares it with a preset QBER threshold. By utilizing the complete interference history information contained in the completed cumulative phase to perform bit error rate statistics, the channel security determination result can reflect the eavesdropping-introduced error in the entire transmission path before and after the addition operation, thereby improving the sensitivity of eavesdropping identification in scenarios of dynamic group changes.

[0181] Step 3: Based on the channel security determination result, terminate the execution of quantum state measurement and disclose the measurement basis and angle parameters to obtain the quantum state measurement result and the disclosed angle set.

[0182] This embodiment terminates the quantum state measurement based on the channel security determination result and discloses the measurement basis and angle parameters. By immediately stopping the measurement and outputting the measurement basis and angle parameters when the channel is insecure, the subsequent decoding process can extract the key based only on the disclosed parameters, thereby blocking the way for eavesdroppers to obtain the original key through the measurement basis information under insecure channels.

[0183] Step 4: Based on the quantum state measurement results and the public angle set, decode to obtain the 256-bit original key.

[0184] In this embodiment, a 256-bit original key is obtained by decoding the quantum state measurement results and the publicly available angle set. By mapping and decoding the angle parameters in the publicly available angle set with the phase difference values ​​in the measurement results bit by bit, the decoding process relies entirely on the publicly available parameters that have been verified by eavesdropping detection. This ensures that the obtained 256-bit original key does not carry unverified channel-introduced errors.

[0185] Step 5: Based on the 256-bit original key and the final priority score, perform block error correction according to the preset priority rules to obtain the corrected key.

[0186] This embodiment performs block error correction according to the 256-bit original key and the final priority score according to the preset priority rules. By using the final priority score as a weighting factor for the block size and parity bit allocation, the correction process prioritizes the processing of errors in high-priority data blocks, thereby reducing the residual error rate of high-priority key blocks under the same parity overhead.

[0187] Step 6: Based on the corrected key and the final priority score, perform privacy amplification calculation according to the preset priority rules to obtain the final key and publish it.

[0188] This embodiment performs privacy amplification calculations based on the corrected key and the final priority score according to preset priority rules. By using the final priority score as an adaptive adjustment parameter for the hash function compression ratio, the privacy amplification process retains more information entropy for high-priority key segments, thereby reducing the randomness loss of high-priority data while ensuring security.

[0189] Step 7: Generate a new key based on the final key, and update the final key with the new key.

[0190] In this embodiment, a new key is generated based on the final key and the new key is used to update the final key. By using the new key as the immediate working key for subsequent group communication and replacing the original final key, the updated key is bound to the real-time state of the quantum channel, thereby avoiding the accumulation of security risks caused by using the same final key for a long time.

[0191] Example 4

[0192] In summary, this invention calculates a basic priority score by weighting and fusing the initial priority of events with event weights, and then recalculates the final priority score after adjusting the event weights based on the QKD network load. This achieves a refined and dynamic evaluation of key update triggering conditions, avoiding resource waste and communication interruptions caused by performing a complete key update process for all events. Simultaneously, by determining the key generation level based on the final priority score and generating a key generation initiation command, key updates are triggered only under necessary conditions, reducing unnecessary updates and lowering the frequency of group meeting interruptions. Furthermore, by performing join compensation calculations based on the quantum states disclosed by participants and node join requests to update the global mask phase, and performing offline compensation calculations based on the global mask phase and node offline status to obtain the completed cumulative phase, a smooth key transition can be achieved through phase compensation without interrupting the meeting when members join or leave. This avoids the high resource consumption caused by the requirement for all participants to re-execute the quantum state preparation, transmission, and measurement processes when members change, as in existing schemes. Additionally, by configuring communication parameters and initializing the node state table, dynamic adaptation of the key update process to the QKD network load status is ensured, improving the efficiency and practicality of quantum key updates in group meetings.

[0193] This invention obtains quantum communication parameters by having participants set communication parameters based on their final priority scores. This achieves dynamic matching between communication parameters, event priorities, and the QKD network load during key updates, avoiding resource waste or performance issues caused by fixed communication parameter configurations. Simultaneously, by executing a quantum state preparation and distribution process based on the quantum communication parameters and publicly disclosing the transmitted quantum state, participants can collaboratively complete the key update process based on unified quantum state information, ensuring consistency and synchronization of key updates across multiple parties in group meetings. Furthermore, by generating a new key based on the final key disclosed by the new participating node through a simplified process and updating the final key, participants can directly complete key switching without additional key negotiation with third parties or other participants after the new key is generated. This further shortens communication interruption time during key updates and improves the efficiency of key updates in group meetings.

[0194] This invention obtains an updated global mask phase by performing a join compensation calculation based on the quantum state transmitted by the participants and the node join request. This allows new participating nodes to seamlessly join the existing key distribution system without interrupting the group meeting, avoiding communication interruptions and resource overhead caused by the need for all participants to re-execute the complete key negotiation process when a new member joins. At the same time, by performing eavesdropping detection based on the supplemented cumulative phase disclosed by a third party and comparing it with a preset QBER threshold to obtain the channel security determination result, channel security verification is completed before key generation, ensuring the security of the key distribution process and avoiding the waste of computational resources caused by performing the subsequent key generation process under insecure channel conditions. Furthermore, by performing quantum state measurements based on the channel security determination results and publicly disclosing the measurement basis and angle parameters, and combining this with decoding to obtain a 256-bit original key, block error correction and privacy amplification calculations are performed sequentially according to the preset priority rules corresponding to the final priority score. This allows the computational complexity of error correction and privacy amplification to dynamically adapt to the key update priority. Low-priority events are simplified to reduce computational overhead, while high-priority events are enhanced to ensure key security, achieving a balance between security and efficiency. Moreover, by generating a new key based on the final key and updating the final key, new participating nodes maintain key synchronization with other members of the group after key generation, ensuring the continuity and security of group conference communication.

[0195] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0196] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0197] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0198] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0199] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. An event-triggered quantum key update method for group conferences, characterized in that, Performed by a third party, including: Based on the initial priority and weight of the event, a weighted fusion model is used to calculate the basic priority score; The correction weight is obtained based on the basic priority score and the QKD network load correction event weight; Based on the initial priority and adjusted weights of the events, a weighted fusion model is used to calculate the final priority score; Based on the final priority score, the key generation level is determined according to a preset threshold, and a key generation start command is generated. The startup command generates a key to set up communication parameter configuration rules and initializes the node status table. Based on the quantum states disclosed by the participants and the node joining requests, the joining compensation calculation is performed to obtain the updated global mask phase; Based on the updated global mask phase and the node offline status in the node status table, perform offline compensation calculation to obtain the completed cumulative phase and publish it. A new key is generated based on the final key disclosed by the new participating node, and the final key is updated using the new key.

2. The event-triggered quantum key update method for group meetings according to claim 1, characterized in that, The basic priority score is represented as follows: ； In the formula, Indicates the basic priority score. Indicates the initial priority. Represents the association weight, where, This indicates a preset high-priority event. This indicates a preset medium-priority event. This indicates a preset low-priority event. This indicates that the incident is a security incident. This indicates that the event is a resource event. This indicates that the event is a network event. This indicates that the event is a user event; The final priority score is expressed as follows: ； In the formula, This indicates the final priority score. This indicates the adjusted weights, where, .

3. The event-triggered quantum key update method for group meetings according to claim 1, characterized in that, Based on the final priority score, the key generation level is determined according to a preset threshold, and a key generation initiation command is generated, including: If the final priority score is greater than the preset threshold, the key generation level is determined based on the adjusted weight to generate the key generation start command. If the final priority score is less than or equal to the preset threshold, the key generation level is determined based on the associated weight to generate the key generation start command.

4. The event-triggered quantum key update method for group meetings according to claim 3, characterized in that, The node status table is represented as follows: ； In the formula, Represents the node status table. Indicates the first The initial priority of each node, Indicates the first The online status identifier of each node, where, Indicates the first Each node is online. Indicates the first One node is offline. Indicates the first The quantum state modulation phase value of each node.

5. The event-triggered quantum key update method for group meetings according to claim 4, characterized in that, Based on the quantum states disclosed by the participants and the node joining requests, a joining compensation calculation is performed to obtain the updated global mask phase, including: The quantum state disclosed by the participating party is transmitted to the new participating node corresponding to the node joining request, and the new participating node selects a phase value from a preset phase set and applies modulation to obtain the node modulation phase; wherein, the preset phase set only includes Discrete angle values ​​within the range; The node modulation phase is represented as: ； In the formula, Indicates the node modulation phase. Indicates a preset phase set; Select the private mask corresponding to the new participating node itself, apply the private mask to the modulation phase of the node, and perform calculation to obtain the new node mask phase; The new node mask phase is represented as: ； In the formula, Indicates the phase of the new node mask. This represents the private mask corresponding to the new node itself; Obtain the new node mask phase sent by the new participating node to the third party through the encrypted classic channel, and perform a modulo addition calculation with the current global mask phase to obtain the updated global mask phase; The updated global mask phase is represented as: ； In the formula, This indicates the updated global mask phase. Indicates the current global mask phase. This represents the modulo addition calculation function.

6. The event-triggered quantum key update method for group meetings according to claim 5, characterized in that, Based on the updated global mask phase and the node offline status in the node status table, perform offline compensation calculations to obtain the completed cumulative phase, which is then made public, including: Based on the offline status of nodes in the node status table, the temporary global mask phase is obtained by subtracting the offline node mask phase corresponding to the exiting participant from the updated global mask phase. The temporary global mask is represented as follows: ； In the formula, Indicates the temporary global mask phase. This indicates the offline node mask phase corresponding to the participant who has left the game; Based on the temporary global mask phase, select an online legitimate participant, and have the online legitimate participant select a new private mask to update the local private mask; Calculate the difference between the new private mask and the local private mask to obtain the mask difference; The mask difference is expressed as: ； In the formula, Indicates the mask difference. This represents the new private mask chosen by legitimate online participants. A local private mask representing a legitimate online participant; The mask difference is modulo-added with the temporary global mask phase to obtain the padded cumulative phase, which is then made public. The completed accumulated phase is represented as: ； In the formula, This indicates the cumulative phase after completion.

7. An event-triggered quantum key update method for group conferences, characterized in that, Executed by the participating parties, including: The quantum communication parameters are obtained by setting the communication parameters based on the final priority score. Based on the quantum communication parameters, the quantum state preparation and distribution process is executed to obtain the transmitted quantum state and make it public; Based on the final key published by the new participating node, a new key is generated through a simplified process, and the final key is updated using the new key.

8. The event-triggered quantum key update method for group meetings according to claim 7, characterized in that, Based on the final priority score, communication parameters are set to obtain quantum communication parameters, including: The key generation level result is obtained based on the final priority score and determined according to a preset threshold. The key generation level result includes a preset high priority and a preset low priority. Based on the key generation level results, the fiber optic channel transmission distance between nodes is obtained and calculated to obtain the quantum bit error rate security threshold. When the key generation level result is a preset high priority, the first decoy state ratio is set, and the quantum error rate security threshold is expressed as: ； In the formula, This represents the quantum error rate security threshold. This represents the bit error rate constant of the basic equipment. Represents the linear attenuation coefficient of optical fiber. Indicates the fiber optic channel transmission distance between nodes; Based on the quantum error rate security threshold and the key generation level result, decoy state configuration processing is performed according to the first decoy state ratio to obtain quantum communication parameters; When the key generation level result is a preset low priority, a second decoy state ratio is set, and the quantum error rate security threshold is set to a preset constant. Based on the quantum error rate security threshold and the key generation level result, decoy state configuration processing is performed according to the second decoy state ratio to obtain quantum communication parameters; Wherein, the ratio of the first deceptive state is less than the ratio of the second deceptive state.

9. The event-triggered quantum key update method for group meetings according to claim 8, characterized in that, Based on the quantum communication parameters, a quantum state preparation and distribution process is executed to obtain and publicly disclose the transmitted quantum state, including: According to the quantum communication parameters, the initial participant generates a normalized single-photon initial state under the corresponding priority, and transmits it to the subsequent participating nodes in the order of the preset nodes to obtain the single-photon transmission quantum state. The single-photon transmission quantum state is represented as: ； In the formula, Indicates a single-photon transport quantum state, subscript Indicates the initial state. and Let represent the orthogonal basis vectors of the horizontally polarized state and the vertically polarized state of the single-photon transmission quantum state, respectively. Represents the probability amplitude coefficient. Represents the superposition of quantum states; Based on the single-photon transmission quantum state, each participating node selects a local selection phase according to the phase selection range corresponding to the priority, and applies Pauli-Z operator modulation to the single-photon transmission quantum state and superimposes its own private mask to calculate the quantum state modulation phase value. The quantum state modulation phase value is then sent to a third party for public disclosure through an encrypted classical channel as the quantum state after transmission is completed. Among them, the The quantum state modulation phase value of each node is expressed as: ； In the formula, Indicates the first The quantum state modulation phase value of each node, Indicates the first Local selection phase of each node Indicates the first The private mask of each node; Wherein, when the key generation level result is a preset high priority, the selection range of the local selection phase is: ; When the key generation level result is a preset low priority, the selection range of the local selection phase is: .

10. An event-triggered quantum key update method for group conferences, characterized in that, Executed by the new participating node, including: Based on the quantum state and node joining request transmitted by the participants, select the local private phase and private mask, calculate the new node mask phase, and send the new node mask phase to the third party; Based on the completed cumulative phase disclosed by a third party, eavesdropping detection is performed and compared with a preset QBER threshold to obtain the channel security determination result. Based on the channel security determination result, the execution of quantum state measurement is terminated and the measurement basis and angle parameters are disclosed, thus obtaining the quantum state measurement result and the disclosed angle set; Based on the quantum state measurement results and the publicly available angle set, the 256-bit original key is decoded. Based on the 256-bit original key and the final priority score, block error correction is performed according to the preset priority rules to obtain the corrected key; Based on the corrected key and the final priority score, privacy amplification calculation is performed according to the preset priority rules to obtain the final key and make it public; A new key is generated based on the final key, and the final key is updated using the new key.

Images