Method and system for routing and resource optimization of hybrid relayed qkd optical networks

Abstract

The application relates to the technical field of quantum key distribution optical network resource allocation, in particular to a hybrid relay QKD optical network routing and resource optimization method and system, the method comprising the following steps: initializing a quantum key distribution optical network; generating a group of service requests based on the quantum key distribution optical network; based on the service requests, taking the minimum number of frequency slot and time slot occupation of the quantum key distribution optical network as the target, constructing an optimization target function and its key rate constraint condition; according to the key rate constraint condition, solving the optimization target function to obtain a routing, frequency spectrum and time slot allocation result. The application can improve the resource utilization efficiency of the quantum key distribution optical network, ensure the safety of data transmission by precisely evaluating the key rate demand of the service request, optimizing resource allocation, considering comprehensive constraint conditions and providing flexible routing selection and systematic solutions.

Description

Technical Field

[0001] This invention relates to the field of quantum key distribution (QKD) optical network resource allocation technology, and in particular to a routing and resource optimization method and system for hybrid relay QKD optical networks. Background Technology

[0002] With the booming development of cloud computing, data centers, and related services, the data traffic carried by optical networks has increased dramatically. At the same time, optical networks are increasingly becoming a key means of transmitting private and sensitive data. However, the rapid improvement in computer performance poses a serious challenge to traditional encryption methods that rely on mathematical computational complexity. Optical network communication is facing multiple security threats such as eavesdropping and data leakage. Against this backdrop, quantum key distribution (QKD) technology is gradually emerging as a powerful tool to ensure the security of optical networks.

[0003] QKD technology fully utilizes the unique principles of quantum mechanics, generating and distributing keys through the manipulation of optical quantum states, demonstrating outstanding anti-eavesdropping potential. Therefore, QKD is widely recognized as one of the core technologies for achieving unconditionally secure communication, providing a novel approach and means for the security protection of optical networks. In recent years, significant progress has been made in both theoretical exploration and experimental verification in this field, and commercial applications have been successfully achieved in a short period.

[0004] Nevertheless, standalone point-to-point QKD links still face numerous limitations in terms of transmission distance and key rate. For long-distance key communication needs, the introduction of QKD relay technology is particularly important. Currently, there are three main QKD relay solutions:

[0005] (1) Quantum repeater-based QKD: This scheme utilizes the quantum entanglement effect to realize the storage and forwarding of quantum states, thereby extending the transmission distance of quantum states. However, due to the still immature nature of quantum storage technology, quantum repeater-based QKD is still in the research and development stage.

[0006] (2) QKD based on trusted relays: This scheme caches the key generated by the point-to-point QKD link at trusted relay nodes and uses a one-time cipher (OTP) hop-by-hop encryption algorithm to achieve end-to-end key transmission. However, it is worth noting that trusted relay nodes may become key targets for eavesdropping attacks in practical applications.

[0007] (3) Measurement-Independent Quantum Key Distribution (MDI-QKD): In the MDI-QKD scheme, a pair of users send signals to an intermediate MDI node for Bell state measurement. The users obtain a secure key based on the measurement results published by the MDI node on a public channel, after further processing. However, the key rate requirements of MDI-QKD limit its further extension of transmission distance.

[0008] Compared to the three schemes mentioned above, the QKD network based on hybrid relay demonstrates greater adaptability in practical deployments. How to efficiently and rationally utilize hybrid relay technology to achieve data transmission and key distribution, and to perform routing planning for different service requests to improve overall key rate and ensure secure data encryption, has become a critical issue that urgently needs to be addressed.

[0009] In addition, given the high cost of building quantum channels, how to reduce resource consumption and improve the utilization efficiency of spectrum and time slot resources to support more service requests to use quantum keys for encryption protection is also an important issue that cannot be ignored. Summary of the Invention

[0010] To address the resource waste and low key rate issues in hybrid relay QKD optical networks during relaying, this invention provides a routing and resource optimization method for hybrid relay QKD optical networks, comprising the following steps:

[0011] S1: Initialize the quantum key distribution network G(N) t N m ,L,W,Δ,T),N t N represents the set of optical backbone nodes and trusted relay nodes. m For a set of quantum key distribution nodes independent of measurement equipment, L represents a set of fiber optic links in the network, where two nodes i and j are connected by a fiber optic link (i,j), (i,j)∈L, W represents the set of available conventional data channels, and Δ and T represent a series of quantum channels and the set of time slots on each quantum channel, respectively.

[0012] S2: Based on the quantum key distribution network, generate a set of service requests R(s,d,w,t,SKR)∈R, where R is the set of service requests, s is the source node, d is the destination node, w is the required number of traditional data channels, t is the required number of time slots, and SKR is the minimum key rate threshold required for the encrypted service request.

[0013] S3: Based on the service request, with the goal of minimizing the number of frequency slots and time slots occupied by the quantum key distribution network, construct an optimization objective function and a key rate constraint condition for the optimization objective function;

[0014] S4: Based on the key rate constraint, solve the optimization objective function to obtain the routing, spectrum, and time slot allocation results.

[0015] In one embodiment of the present invention, in S3, the expression of the optimization objective function is as follows:

[0016]

[0017] in, and Both represent binary variables, where (i,j) represents the fiber optic link from node i to node j, and Minimize represents the operation of minimizing spectrum and time slot occupancy. When a service request from source node s to destination node d occupies the frequency slot numbered λ on the traditional data channel of the fiber optic link (i,j), otherwise When a service request from source node s to destination node d occupies time slot t in slot λ on the quantum channel of fiber link (i,j), otherwise

[0018] In one embodiment of the present invention, the key rate constraint includes a flow conservation constraint for service requests, a spectrum and time slot continuity constraint, a spectrum and time slot unique occupancy constraint, a frequency slot and time slot identity constraint, and a constraint that the key generation rate of the key transmission path is greater than or equal to the minimum key rate requirement threshold of the service request.

[0019] In one embodiment of the present invention, the expression for the flow conservation constraint condition of the service request is as follows:

[0020]

[0021]

[0022]

[0023] Specifically, when a service request from source node s to destination node d occupies a spectrum slot numbered λ on the quantum channel of fiber link (i,j), otherwise

[0024] In one embodiment of the present invention, the spectrum and time slot continuity constraints are divided into frequency slot continuity constraints and time slot continuity constraints, as follows:

[0025] For spectrum resources, the frequency slot selected by each service request R(s,d,w,t,SKR) must satisfy the frequency slot continuity constraint, that is:

[0026] In traditional data channels, when and At that time, the frequency slots with numbers greater than or equal to λ+2 were not occupied by any other service requests:

[0027]

[0028] when The frequency slots with numbers less than λ have been occupied by service request R(s,d,w,t,SKR):

[0029]

[0030] In quantum channels, when binary variables and At that time, the frequency slots with numbers greater than or equal to λ+2 were not occupied by any service requests:

[0031]

[0032] when The frequency slots with numbers less than λ have been occupied by service request R(s,d,w,t,SKR):

[0033]

[0034] Where θ represents a preset positive integer, n (s,d) This represents the number of frequency slots required for service requests between the source node s and the destination node d;

[0035] For time slot resources, the time slot selected by each service request R(s,d,w,t,SKR) must satisfy the time slot continuity constraint, that is:

[0036] When binary variables and At that time, time slots with numbers greater than or equal to t+2 were not occupied by any other service requests:

[0037]

[0038] when Time slots with numbers less than t have been occupied by service request R(s,d,w,t,SKR):

[0039]

[0040] Among them, t (s,d) This represents the number of time slots required for a service request to travel from the source node s to the destination node d.

[0041] In one embodiment of the present invention, the unique occupancy constraint of the spectrum and the unique occupancy constraint of the time slot are divided into a unique occupancy constraint of the spectrum and a unique occupancy constraint of the time slot.

[0042] The unique spectrum occupancy constraint means that a frequency slot can only be occupied by one service request and cannot be occupied by two or more service requests simultaneously.

[0043]

[0044] The unique occupancy constraint of a time slot means that a time slot can only be occupied by one service request, and cannot be occupied by two or more service requests at the same time.

[0045]

[0046] In one embodiment of the present invention, the frequency slot and time slot identity constraint means that for each service request R(s,d,w,t,SKR), the frequency slot occupied by its time slot is the same as the spectrum used by the service request, that is:

[0047]

[0048]

[0049] Where θ represents a preset positive integer.

[0050] In one embodiment of the present invention, the constraint that the key generation rate of the key transmission path is greater than or equal to the minimum key rate requirement threshold of the service request means that the key generation rate on the key transmission path of each service request at least reaches the minimum key rate requirement threshold of the service request, that is:

[0051]

[0052]

[0053]

[0054]

[0055]

[0056] Among them, KR (s,d) This represents the minimum key rate threshold required for a service request R(s,d,w,t,SKR) from source node s to destination node d. Represents a binary variable, which is used when the fiber optic link (i,j) on the key transmission path is requested by a service. otherwise Represents a binary variable, which is used when the fiber optic link (i,j) on the key transmission path is requested by a service. otherwise, It equals a positive integer N.

[0057] In one embodiment of the present invention, the key generation rate KR on the key transmission path of the service request p :

[0058] KRp =min (i,j)∈p KR (i,j)

[0059] Among them, KR (i,j) This represents the lower bound of the secure key rate between nodes i and j, where p is the entire key transmission path including relay nodes. Q1 is the single-photon state gain, H2(x) is the binary Shannon information function, E is the bit error rate of the qubit, P0 is the vacuum state yield, and γ is the misalignment of the optical element; Q is the channel gain, Q = P0 + 1 - e -μθ μ represents the average number of photons sent at specified time intervals.

[0060] Based on the same inventive concept, this invention also provides a routing and resource optimization system for a hybrid relay QKD optical network, used to implement the routing and resource optimization method for the hybrid relay QKD optical network. The system includes the following modules:

[0061] The network initialization module is used to initialize the quantum key distribution network;

[0062] The service request generation module is used to generate a set of service requests based on the quantum key distribution network.

[0063] The objective function construction module is used to construct an optimization objective function and the key rate constraint conditions of the optimization objective function based on the business request, with the goal of minimizing the number of frequency slots and time slots occupied by the quantum key distribution network;

[0064] The resource allocation module is used to solve the optimization objective function based on the key rate constraint to obtain routing, spectrum, and time slot allocation results.

[0065] The technical solution of the present invention has the following advantages compared with the prior art:

[0066] This invention primarily routes and allocates service requests and evaluates their key rates. The goal is to meet the key rate requirement threshold of each service request, ensuring sufficient key encryption for secure transmission. Simultaneously, based on the spectrum and time slot requirements of each service request, necessary spectrum and time slot resources are allocated, resolving the routing, spectrum, and time slot allocation issues. The optimization function aims to minimize spectrum and time slot resource usage, satisfying constraints such as flow conservation, spectrum and time slot consistency, spectrum and time slot continuity, unique spectrum and time slot occupancy, spectrum and time slot identity, and the key generation rate of the key transmission path being greater than or equal to the minimum key rate requirement threshold of the service request. This yields an optimal solution for the spectrum and time slot resource usage of a known set of service requests, solving the optimization routing, spectrum, and time slot allocation problem based on key rate constraints, thereby improving the resource utilization efficiency of the quantum key distribution network. Attached Figure Description

[0067] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein...

[0068] Figure 1 This is a flowchart of the routing and resource optimization method for a hybrid relay QKD optical network provided in Embodiment 1 of the present invention;

[0069] Figure 2 This is a flowchart illustrating the routing and resource optimization method for a hybrid relay QKD optical network provided in Embodiment 1 of the present invention.

[0070] Figure 3 This is a schematic diagram of the key generation rate of a fiber optic link in a QKD optical network.

[0071] Figure 4 There are two business requests R(0,2,1,2,1.29×10). -4 ) and R(3,5,2,1,1.32×10 -4 A schematic diagram illustrating the optimal solution for routing, spectrum, and time slot allocation methods.

[0072] Figure 5 This is a schematic diagram of the routing and resource optimization system structure of the hybrid relay QKD optical network provided in Embodiment 2 of the present invention;

[0073] Explanation of reference numerals in the accompanying drawings: 10, Network initialization module; 20, Service request generation module; 30, Objective function construction module; 40, Resource allocation module. Detailed Implementation

[0074] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0075] Example 1

[0076] Reference Figure 1 and Figure 2 As shown, this invention provides a routing and resource optimization method for a hybrid relay QKD optical network, which includes the following steps:

[0077] S1: Initialize the quantum key distribution network G(N) t N m ,L,W,Δ,T),N t N represents the set of optical backbone nodes and trusted relay nodes. m For a set of quantum key distribution nodes independent of measurement equipment, L represents a set of fiber optic links in the network, where two nodes i and j are connected by a fiber optic link (i,j), (i,j)∈L, W represents the set of available traditional data channels, and Δ and T represent a series of quantum channels and the set of time slots on each quantum channel, respectively; |N t |、|N m |, |L|, |W|, |Δ|, and |T| represent the number of optical backbone nodes and trusted relay nodes, the number of MDI-QKD nodes, the number of fiber optic links, the number of traditional data channels, the number of quantum channels, and the number of time slots in the quantum channels, respectively.

[0078] S2: Based on the quantum key distribution network, generate a set of service requests R(s,d,w,t,SKR)∈R, where R is the set of service requests, s is the source node, d is the destination node, w is the required number of traditional data channels, t is the required number of time slots, and SKR is the minimum key rate threshold required for the encrypted service request.

[0079] S3: Based on the service request, with the goal of minimizing the number of frequency slots and time slots occupied by the quantum key distribution network, construct an optimization objective function and a key rate constraint condition for the optimization objective function;

[0080] S4: Based on the key rate constraint, solve the optimization objective function to obtain the routing, spectrum, and time slot allocation results.

[0081] In this embodiment, in S3, the expression of the optimization objective function is as follows:

[0082]

[0083] in, and Both represent binary variables, where (i,j) represents the fiber optic link from node i to node j, and Minimize represents minimizing the spectrum and time slot occupancy. On one hand, when a service request from source node s to destination node d occupies the frequency slot numbered λ on the traditional data channel of the fiber optic link (i,j), otherwise On the other hand, when a service request from source node s to destination node d occupies time slot t in slot λ on the quantum channel of fiber link (i,j), otherwise

[0084] Furthermore, the key rate constraints include flow conservation constraints for service requests, spectrum and time slot continuity constraints, unique occupancy constraints for spectrum and time slots, frequency slot and time slot identity constraints, and constraints that the key generation rate of the key transmission path is greater than or equal to the minimum key rate requirement threshold of the service request.

[0085] Specifically, the expression for the flow conservation constraint of the service request is as follows:

[0086]

[0087]

[0088]

[0089] Specifically, when a service request from source node s to destination node d occupies the spectrum slot numbered λ on the quantum channel of the fiber link (i,j), otherwise

[0090] The frequency spectrum and time slot continuity constraints are divided into frequency slot continuity constraints and time slot continuity constraints, as follows:

[0091] For spectrum resources, the frequency slot selected by each service request R(s,d,w,t,SKR) must satisfy the frequency slot continuity constraint, that is:

[0092] In traditional data channels, when and At that time, the frequency slots with numbers greater than or equal to λ+2 were not occupied by any other service requests:

[0093]

[0094] when The frequency slots with numbers less than λ have been occupied by service request R(s,d,w,t,SKR):

[0095]

[0096] In quantum channels, when binary variables and At that time, the frequency slots with numbers greater than or equal to λ+2 were not occupied by any service requests:

[0097]

[0098] when The frequency slots with numbers less than λ have been occupied by service request R(s,d,w,t,SKR):

[0099]

[0100] Where θ represents a very large positive integer n. (s,d) This represents the number of frequency slots required for service requests between the source node s and the destination node d;

[0101] For time slot resources, the time slot selected by each service request R(s,d,w,t,SKR) must satisfy the time slot continuity constraint, that is:

[0102] When binary variables and At that time, time slots with numbers greater than or equal to t+2 were not occupied by any other service requests:

[0103]

[0104] when Time slots with numbers less than t have been occupied by service request R(s,d,w,t,SKR):

[0105]

[0106] Among them, t (s,d) This represents the number of time slots required for a service request to travel from the source node s to the destination node d.

[0107] The unique occupancy constraints of the spectrum and time slot are divided into unique occupancy constraints of the spectrum and unique occupancy constraints of the time slot.

[0108] The unique spectrum occupancy constraint means that a frequency slot can only be occupied by one service request and cannot be occupied by two or more service requests simultaneously.

[0109]

[0110] The unique occupancy constraint of a time slot means that a time slot can only be occupied by one service request, and cannot be occupied by two or more service requests at the same time.

[0111]

[0112] The constraint that frequency slots and time slots are identical means that for each service request R(s,d,w,t,SKR), the frequency slot occupied by its time slot is the same as the spectrum used by the service request, that is:

[0113]

[0114]

[0115] Where θ represents a preset positive integer.

[0116] The constraint that the key generation rate of the key transmission path is greater than or equal to the minimum key rate requirement threshold of the service request means that the key generation rate on the key transmission path of each service request at least reaches the minimum key rate requirement threshold of the service request, that is:

[0117]

[0118]

[0119]

[0120]

[0121]

[0122] Among them, KR (s,d) This represents the minimum key rate threshold required for a service request R(s,d,w,t,SKR) from source node s to destination node d. Represents a binary variable, which is used when the fiber optic link (i,j) on the key transmission path is requested by a service. otherwise Represents a binary variable, which is used when the fiber optic link (i,j) on the key transmission path is requested by a service. otherwise, It equals a positive integer N.

[0123] Among them, the key generation rate KR on the key transmission path of the service request p :

[0124] KR p =min (i,j)∈p KR (i,j) (20)

[0125] Among them, KR (i,j)This represents the lower bound of the secure key rate between nodes i and j, where p is the entire key transmission path including relay nodes. Q1 is the single-photon state gain, H2(x) is the binary Shannon information function, E is the bit error rate of the qubit, P0 is the vacuum state yield, and γ is the misalignment of the optical element; Q is the channel gain, Q = P0 + 1 - e -μθ μ represents the average number of photons sent at specified time intervals.

[0126] To minimize the spectrum time slot resources occupied by a set of service requests, the quantum key distribution network G(N) is first analyzed. t N m The process involves initializing the network (L, W, Δ, T) by including network topology information, optical backbone nodes and trusted relay nodes, MDI-QKD nodes, fiber optic links, traditional data channels, quantum channels, and time slots. Next, a set of service requests is generated, including the source node, destination node, spectrum and time slot requirements, and minimum required key rate threshold. Finally, an optimization function based on key rate constraints is applied, satisfying the following constraints: flow conservation of service requests, spectrum and time slot continuity, unique spectrum and time slot occupancy, spectrum and time slot identity, and the key generation rate of the key transmission path being greater than or equal to the minimum key rate threshold of the service request. This yields the optimal solution for spectrum and time slot resource occupancy. A specific implementation example is as follows:

[0127] First, initialize as follows Figure 3 The quantum key distribution network shown has bidirectional fiber links, and the values ​​on the fiber links represent unavailability. The number of traditional data channels and the number of quantum channels are set to 3 and 2 respectively for each fiber link, and the number of time slots on each quantum channel is set to 3.

[0128] Secondly, based on the aforementioned quantum key distribution network, a set of service requests R(0,2,1,2,1.29×10) is generated. -4 ) and R(3,5,2,2,1.32×10 -4 ).

[0129] Then, the optimization function of the dedicated protection route, spectrum, and time slot allocation method based on key rate constraints is executed to satisfy the flow conservation constraints, spectrum and time slot continuity constraints, time slot unique occupancy constraints, spectrum and time slot identity constraints, and the constraint that the key generation rate of the working path is greater than or equal to the minimum key rate requirement threshold of the service request.

[0130] Finally, the optimization function solution based on the key rate constraint is obtained as 16, meaning that the minimum required time slots to satisfy the key rate constraint are 16. For example... Figure 4 As shown, the service request R(0,2,1,2,1.29×10) -4) and R(3,5,2,2,1.32×10 -4 The selected data transmission paths are (0-1-2) and (3-4-5), corresponding to traditional data channel numbers 1 and 1,2. The selected key transmission paths are (0-5-1-2) and (3-4-5), corresponding to traditional data channel numbers 1,2 and 1,2. According to the optimization objective of minimizing spectrum and time slot occupancy, path (0-1-2) should be selected as both the data transmission path and the key transmission path. However, due to the constraint that the key generation rate of the key transmission path must be greater than or equal to the minimum key rate requirement threshold of the service request, the key generation rate of path (0-1-2) is 8.51 × 10⁻⁶. -5 The business request R(0,2,1,2,1.29×10) cannot be satisfied. -4 The minimum key rate requirement constraint is 0-5-1-2. Therefore, it is necessary to find the path that occupies the least spectrum and time slot resources while satisfying the constraint. Using formula (20), the service request R(0,2,1,2,1.29×10) is calculated. -4 The key generation rate of the selected key transmission path is 1.69 × 10⁻⁶. -4 It is greater than the minimum key requirement rate of 1.32 × 10 for this service request. -4 If the key transmission path (0-5-1-2) established by this service request satisfies the constraint that the key generation rate of the key transmission path is greater than or equal to the minimum key rate requirement threshold of the service request, then this path is ultimately selected for key transmission. Similarly, using formula (20), the service request R(3,5,2,2,1.32×10 -4 The minimum key generation rate requirement for the selected data transmission path and key transmission path is 1.36 × 10⁻⁶. -4 The data transmission path and key transmission path (3-4-5) established by this business request also satisfy the condition that the key generation rate is greater than or equal to the minimum key rate requirement threshold of 1.32 × 10⁻⁶ for the business request. -4 The constraints.

[0131] Example 2

[0132] Based on the same inventive concept as Embodiment 1, this invention also provides a routing and resource optimization system for a hybrid relay QKD optical network, used to implement the routing and resource optimization method for the hybrid relay QKD optical network described in Embodiment 1. Figure 5 As shown, the system includes the following modules:

[0133] Network initialization module 10 is used to initialize the quantum key distribution network;

[0134] The service request generation module 20 is used to generate a set of service requests based on the quantum key distribution network.

[0135] The objective function construction module 30 is used to construct an optimization objective function and the key rate constraint conditions of the optimization objective function based on the service request, with the goal of minimizing the number of frequency slots and time slots occupied by the quantum key distribution network.

[0136] The objective function construction module 30 further includes a service request flow conservation constraint submodule, a spectrum and time slot continuity constraint submodule, a spectrum and time slot unique occupancy constraint submodule, a spectrum and time slot identity constraint submodule, a working path key rate calculation module, and a service minimum requirement key rate threshold constraint submodule. The implementation functions of each module are the same as those described in Embodiment 1 regarding the key rate constraints and the key generation rate KR on the key transmission path of the service request. p The implementation process is the same, so it will not be described in detail here;

[0137] The resource allocation module 40 is used to solve the optimization objective function based on the key rate constraint to obtain routing, spectrum, and time slot allocation results.

[0138] This embodiment proposes a routing and resource optimization system for a hybrid relay QKD optical network, which is used to implement the aforementioned routing and resource optimization method for a hybrid relay QKD optical network. Therefore, the specific implementation of the routing and resource optimization system for a hybrid relay QKD optical network can be found in the embodiment section of the aforementioned routing and resource optimization method for a hybrid relay QKD optical network. For example, the network initialization module 10, the service request generation module 20, the objective function construction module 30, and the resource allocation module 40 are respectively used to implement steps S1, S2, S3, and S4 in the routing and resource optimization method for a hybrid relay QKD optical network described in Embodiment 1. Therefore, its specific implementation can be referred to the description of the corresponding embodiments. To avoid redundancy, it will not be repeated here.

[0139] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application 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.

[0140] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. 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... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0141] 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.

[0142] 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.

[0143] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for routing and resource optimization of a hybrid relayed QKD optical network, characterized in that, The method comprises the following steps: S1: Initialization of a quantum key distribution optical network , denotes a set of optical backbone nodes and trusted relay nodes, is a set of quantum key distribution nodes independent of the measurement devices, denotes a set of fiber links of the network, two nodes i and j form a fiber link connected, , denotes a set of available conventional data channels, and denote a set of quantum channels and a set of time slots on each quantum channel, respectively; S2: generating a set of service requests based on the quantum key distribution optical network , for the set of service requests, for the source node, for the destination node, for the number of required legacy data channels, for the number of required time slots, for the minimum key rate threshold required for encrypting the service requests; S3: based on the service request, minimizing the number of frequency slots and time slots occupied by the quantum key distribution optical network as the target, constructing an optimization objective function and a key rate constraint condition of the optimization objective function; the key rate constraint condition includes a constraint condition that the key generation rate of the key transmission path is greater than or equal to the minimum key rate requirement threshold of the service request, wherein the key generation rate of the key transmission path is is calculated as follows: ， wherein, denotes a lower bound of a secure key rate between nodes , denotes a whole key transfer path including a relay node, , denotes a single-photon state gain, denotes a binary Shannon information function, denotes a quantum bit error rate, denotes a vacuum state fidelity, denotes a misalignment of an optical element; denotes a channel gain, , denotes an average number of photons transmitted according to a specified time interval, denotes a predetermined positive integer; S4: based on the key rate constraint condition, the optimization objective function is solved to obtain the routing, spectrum, and time slot allocation result. 2.The method of Claim 1, wherein, In S3, the expression of the optimization objective function is as follows: wherein, and both represent binary variables, represents the fiber link between node i and node j, represents the minimization of spectrum and time slot occupation operations; when a traffic request between a source node and a destination node occupies a frequency slot numbered on the conventional data channel of the fiber link , otherwise ; when a traffic request between a source node s and a destination node d occupies the th time slot in a frequency slot numbered on the quantum channel of the fiber link , otherwise . 3.The method of Claim 2, wherein, The key rate constraint condition comprises a flow conservation constraint condition of the service request, a spectrum and time slot continuity constraint condition, a spectrum and time slot unique occupation constraint condition, and a frequency slot and time slot identity constraint condition.

4. The method of Claim 3, wherein, The expression of the flow conservation constraint condition of the service request is as follows: ， ， ， wherein, when a traffic request between a source node s and a destination node d occupies a spectrum slot numbered on a quantum channel of a fiber link , then , otherwise .

5. The method of Claim 3, wherein, The spectrum and time slot continuity constraint condition comprises a frequency slot continuity constraint condition and a time slot continuity constraint condition, as follows: For spectrum resources, each service request The selected frequency slots must satisfy the frequency slot continuity constraint, i.e. On the conventional data channel, when and the frequency slots numbered greater than or equal to are not requested by any other service: ， When the number of slots is less than the number of slots has been occupied by traffic requests : ， On a quantum channel, when the binary variable and is equal to 0, the frequency slots with number greater than or equal to are not occupied by any traffic request: ， When the number of slots less than has been requested by the service occupied: ， wherein, represents a preset positive integer, represents the number of frequency slots required for a service request between a source node s and a destination node d . For time slot resources, each service request The selected time slots must satisfy the time slot continuity constraint, i.e. When the binary variable and the time slots numbered greater than or equal to are not occupied by any other service request: ， When the number of timeslots occupied by traffic requests is less than ； wherein, represents the number of time slots required for a service request between a source node s and a destination node d .

6. The method of Claim 3, wherein, The spectrum and time slot unique occupation constraint condition comprises a spectrum unique occupation constraint condition and a time slot unique occupation constraint condition. The spectrum unique occupation constraint condition refers to that one frequency slot can be occupied by only one service request and cannot be occupied by two or more service requests simultaneously. ; The time slot unique occupation constraint means that one time slot can only be occupied by one service request, and cannot be occupied by two or more service requests at the same time: .

7. The method of Claim 3, wherein, The same frequency slot constraint means that for each service request the frequency slot occupied by the time slot is the same frequency slot as the frequency spectrum used by the service request, that is, , wherein, denotes a predetermined positive integer. 8.The method of Claim 3, wherein, The constraint condition that the key generation rate of the key transmission path is greater than or equal to the minimum key rate requirement threshold of the service request is that the key generation rate on the key transmission path of each service request at least reaches the minimum key rate requirement threshold of the service request, that is: ， ， ， ， ， wherein denotes the minimum key rate threshold required for a service request from a source node s to a destination node d ; denotes a binary variable that is equal to one when an optical fiber link on the key transport path is used by the service request, and zero otherwise; denotes a binary variable that is equal to one when an optical fiber link on the key transport path is used by the service request, and zero otherwise; ; denotes a binary variable that is equal to one when an optical fiber link on the key transport path is used by the service request, and zero otherwise, ; denotes a positive integer N. 9.A system for routing and resource optimization of a hybrid relayed QKD optical network, characterized in that, The system for implementing the routing and resource optimization method of the hybrid relay QKD optical network as claimed in any one of claims 1 to 8 comprises the following modules: A network initialization module for initializing the quantum key distribution optical network; A service request generation module for generating a group of service requests based on the quantum key distribution optical network; An objective function construction module for constructing an optimization objective function and a key rate constraint condition of the optimization objective function based on the service request, with the minimum number of frequency slots and time slots occupied in the quantum key distribution optical network as the target; A resource allocation module for solving the optimization objective function based on the key rate constraint condition to obtain the routing, spectrum, and time slot allocation result.

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