A vehicle network task offloading method for complex road conditions based on SFC

Abstract

The present invention seeks protection for a method for offloading tasks in a vehicle network with complex road conditions based on SFC, and belongs to the field of communication technology. In view of the problem that the diversity of vehicle movement directions and speeds in a vehicle network with complex road conditions may cause high time variability in network status, thereby leading to a decrease in network resource utilization and an increase in task offloading delay, a method for offloading tasks in a vehicle network with complex road conditions based on SFC is proposed. The method searches for cooperative vehicles to construct SFC mapping decisions based on the duration of the inter-vehicle communication link and the status of on-board computing resources, plans SFC resource allocation decisions based on the task delay requirements of vehicle users, and uses the mapping probability distribution of cooperative vehicles to iteratively optimize the SFC mapping decisions and resource allocation decisions, thereby maximizing network resource utilization, effectively improving the task offloading completion rate, and reducing the system unit task delay.

Description

Technical Field

[0001] The present invention belongs to the field of communication technology, and in particular relates to a method for offloading network tasks of vehicles in complex road conditions based on SFC. Background Art

[0002] With the rapid development of the Internet of Things and wireless communication technologies, vehicle networks have become a vital component of communication networks. By moving cloud server resources to in-vehicle systems at the network edge, users can be provided with a variety of compute-intensive and latency-sensitive task offloading services, such as autonomous driving, intelligent transportation systems, and image-assisted navigation. Network Function Virtualization (NFV) software-based and modularizes network functions, enabling the implementation of diverse virtual network functions (VNFs) on top of physical networks. By organizing and orchestrating VNFs within the vehicle edge network and building the service function chaining (SFC) required for user services, multifunctional network resource deployment can be achieved efficiently and flexibly, effectively improving the user's quality of service experience.

[0003] Existing research on vehicle network task offloading usually only considers the offloading of single-function tasks under simple road conditions, and does not consider the inter-vehicle collaborative offloading of multi-function tasks under complex road conditions, such as when the driving direction and speed of each vehicle are random and variable. Existing research on SFC orchestration and deployment mostly considers VNF mapping and SFC deployment problems on static network nodes, and does not consider VNF mapping and SFC deployment problems on dynamic vehicle nodes. The problem involved in the present invention mainly considers the impact of the dynamic and time-varying characteristics of vehicle networks with complex road conditions on the sustainability and effectiveness of SFC, which in turn poses a serious challenge to the quality and performance of multi-function task offloading. In response to the above problems, the present invention proposes a method for offloading complex road vehicle network tasks based on SFC, according to the future development trend of vehicle networks and the business needs of on-board terminals. By searching for cooperative vehicles in a complex dynamic network topology, VNF mapping and SFC deployment are achieved, and resource utilization is maximized, thereby effectively improving the task offloading completion rate and reducing the system unit task delay. Summary of the Invention

[0004] The present invention aims to solve the above problems of the prior art. It proposes a method for offloading network tasks of vehicles in complex road conditions based on SFC. The technical solution of the present invention is as follows:

[0005] A method for offloading network tasks of vehicles in complex road conditions based on SFC, comprising the following steps:

[0006] 101. According to vehicle i* The task offloading request is proposed to initialize the optimal deployment fitness Q of the service function chain SFC * =0, counting variable h=0;

[0007] 102. Let h = h + 1. If h ≤ H, where H represents the maximum number of SFCs required to search for task offloading in the entire vehicle set I, jump to step 103. Otherwise, jump to step 106.

[0008] 103. Build and update the node and link mapping decision {A, B} of the SFC based on the ordered set F of virtual network functions (VNFs) required for task offloading. If successful, jump to step 104; otherwise, jump to step 102.

[0009] 104. Build and update resource allocation decision C based on the SFC mapping decision {A, B}. If successful, jump to step 105; otherwise, jump to step 102.

[0010] 105. According to the SFC deployment decision {A, B, C}, calculate the corresponding deployment fitness Q. If Q * ≤Q, let Q * =Q, optimal SFC deployment decision {A * ,B * ,C *}={A,B,C}, jump to step 102, otherwise, jump to step 102;

[0011] 106. Output the optimal SFC deployment strategy {A * ,B * ,C *};

[0012] 107. End.

[0013] Furthermore, the step 103 constructs and updates the node and link mapping decision {A, B} of the SFC, specifically including the following steps:

[0014] 1) Initialize the temporary set I′=I, Temporary variable τ=i * , counting variables k=0, l=0;

[0015] 2) Let k = k + 1. If k ≤ |F|, jump to step 3). Otherwise, jump to step 7.

[0016] 3) Add the vehicles with SFC k-th VNF type instance and the idle vehicles that are not instantiated in set I′ to set I″, if Jump to step 4), otherwise, jump to step 8);

[0017] 4) For each vehicle i in the set I″, calculate the minimum cost path from vehicle node τ to i And remove the nodes that do not have the minimum cost path from the set I″;

[0018] 5) If Update the node mapping probability ρ of each vehicle i in the set I″ i , and according to the probability distribution {ρ i | i∈I″ Randomly select vehicle i from I″ and jump to step 6); otherwise, jump to step 8);

[0019] 6) Add vehicle i as the kth VNF mapping node to the node mapping decision A, and add the path Add the vehicle i as the lth virtual link to the link mapping decision B, set τ = i, l = l + 1, delete vehicle i from the set I′, and jump to step 2);

[0020] 7) Output SFC mapping decision {A, B};

[0021] 8) The algorithm ends.

[0022] Furthermore, in step 4), the minimum cost path from vehicle node τ to i is calculated The methods specifically include:

[0023] According to the cost w of each physical link e in the vehicle network e The calculation method is shown in formula (1). The minimum cost path algorithm is used to calculate the minimum cost path from vehicle node τ to i.

[0024]

[0025] In formula (1), represents the remaining available bandwidth resources of physical link e, b e represents the total bandwidth resource of the physical link e, b represents the task transmission bandwidth, T represents the task tolerance delay, t i,i′ represents the duration of the communication link between vehicle i and vehicle i′, t i,i′ The value of is calculated by formula (2):

[0026]

[0027] In formula (2), x i with y i , x i′ with y i′ Represent the position coordinates of vehicles i and i′ respectively, v i With v i′ denote the speeds of vehicles i and i′, θi and θ i′ Denote the driving direction angles of vehicles i and i′, v i cosθ i With v i′ cosθ i′ denote the horizontal speeds of vehicles i and i′, v i sinθ i With v i′ sinθ i′ They represent the vertical speeds of vehicles i and i′ respectively, and r represents the effective communication range of the vehicle.

[0028] Furthermore, the node mapping probability ρ of each vehicle i in step 5) is i The calculation method is shown in formula (3):

[0029]

[0030] In formula (3), β i represents the shared weight factor, is the remaining available computing resources of vehicle i The ratio of the total computing resources of vehicle i represents the normalized remaining available computing resources of vehicle i.

[0031] Furthermore, the method for constructing and updating the resource allocation decision C in step 104 includes the following steps:

[0032] 11) According to the node mapping decision A, the SFC mapping nodes are sequentially added to the temporary ordered set I′. According to the link mapping decision B, the bandwidth b required by the virtual link is added to the SFC resource allocation decision C, and the total task transmission delay t on the offload path is obtained. tra , where t tra is the cumulative transmission delay of task data through each physical link on the offloading path, and the counting variable k is set to 0;

[0033] 12) Allocate the basic computing resources c0 required for VNF instantiation to each vehicle i in the set I′ that does not have a corresponding VNF instance, and update the remaining available computing resources

[0034] 13) Let k = k + 1. If k ≤ |I′|, jump to step 14). Otherwise, jump to step 15).

[0035] 14) Based on the remaining available computing resources of the k-th vehicle i in the set I′ Given the task data volume d and task complexity ω, calculate the task computing resources required by the k-th VNF on vehicle i Skip to step 13);

[0036] 15) According to Calculate the task offloading completion delay t. If t>T, jump to step 16). Otherwise, jump to step 17.

[0037] 16) Based on the remaining available computing resources of the vehicle The value of will sort the elements in the set I′ in descending order. If the remaining available computing resources of the first car i in the set I′ make Jump to step 15), otherwise, jump to step 18);

[0038] 17) Output SFC resource allocation decision C;

[0039] 18) The algorithm ends.

[0040] Furthermore, the task computing resources required by the kth VNF on vehicle i in step 14) are The calculation method is shown in formula (4):

[0041]

[0042] Furthermore, the calculation method of the task offloading completion delay t in step 15) is shown in formula (5):

[0043] t=t tra +t com (5)

[0044] In formula (5), t tra represents the total delay of task transmission, t com It represents the total delay of task calculation, and the calculation method is shown in formula (6):

[0045]

[0046] Furthermore, the calculation method of the fitness Q of the SFC deployment decision {A, B, C} in step 105 is shown in formula (7):

[0047]

[0048] In formula (7), and They represent the normalized computing resources and normalized bandwidth resources required for task offloading, represents the normalized task offloading completion delay, 0≤α1≤1, 0≤α2≤1, 0≤α3≤1, where, The calculation method is shown in formulas (8), (9), and (10):

[0049]

[0050]

[0051]

[0052] In formula (8), represents the total computing resources of vehicle i. In formula (9), E represents the set of all physical links in the vehicle network.

[0053] An electronic device comprises a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, the method for offloading network tasks of a vehicle under complex road conditions based on SFC as described in any one of the above is implemented.

[0054] A non-transitory computer-readable storage medium stores a computer program, wherein when the computer program is executed by a processor, the method for offloading complex road condition vehicle network tasks based on SFC is implemented as described in any one of the above.

[0055] The advantages and beneficial effects of the present invention are as follows:

[0056] This paper discloses a method for offloading vehicle network tasks under complex road conditions based on SFC. Existing research on vehicle network task offloading typically only considers offloading single-function tasks under simple road conditions, but fails to consider the collaborative offloading of multi-function tasks between vehicles under complex road conditions, such as those where each vehicle's driving direction and speed are random and variable. Furthermore, existing research on SFC orchestration and deployment mostly focuses on VNF mapping and SFC deployment on static network nodes, but not on dynamic vehicle nodes. In a vehicle network with complex road conditions, the diversity of vehicle movement directions and speeds may cause high time-variability in network status, thereby leading to a decrease in network resource utilization and an increase in task offloading latency. In this paper, the present invention first selects cooperative vehicles based on the duration of the inter-vehicle communication link and the status of on-board computing resources under complex road conditions, optimizes resource utilization and constructs SFC mapping decisions through the VNF instance sharing mechanism, then plans VNF resource configuration and constructs SFC resource allocation decisions based on the task latency requirements of vehicle users. Finally, through iterative optimization of SFC mapping and resource allocation decisions, network resource utilization is maximized, thereby improving the task offloading completion rate and reducing the system unit task latency. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 The present invention provides a flowchart of a method for offloading network tasks of vehicles in complex road conditions based on SFC in a preferred embodiment. DETAILED DESCRIPTION

[0058] The following will describe the technical solutions in the embodiments of the present invention in detail with reference to the accompanying drawings. The described embodiments are only a part of the embodiments of the present invention.

[0059] The technical solution of the present invention to solve the above technical problems is:

[0060] The concepts and models involved in the content of this invention are as follows.

[0061] 1. Network Model

[0062] The present invention assumes that in a vehicle network with complex road conditions, each vehicle travels at any speed and in any direction. Based on the effective communication distance constraint, vehicles can use V2V direct links or V2V multi-hop links to forward communications. Each vehicle carries a server with a certain computing power and can deploy a VNF instance of any type. Based on the task offloading request of the vehicle user, the vehicle network can organize and orchestrate collaborative vehicles with corresponding VNF instances to build the required SFC and provide task offloading services. Among them, the same type of VNF instance can be shared by different SFCs, and VNFs on the same SFC cannot be mapped to the same collaborative vehicle.

[0063] 2. Other symbols involved in the present invention are explained as follows.

[0064] (x i ,y i ): Position coordinates of vehicle i

[0065] v i : The speed of vehicle i

[0066] θ i : driving direction angle of vehicle i

[0067] F: Ordered set of VNFs required for the task

[0068] d: Task data volume

[0069] ω: Task complexity

[0070] b: Task transmission bandwidth

[0071] T: Task tolerance delay

[0072] I: All vehicles gather

[0073] H: Maximum number of times to search for SFC

[0074] w e : The cost of the physical link e in the vehicle network

[0075] ρ i : Vehicle i selection probability

[0076] ti,i′ : Duration of the communication link between vehicles i and i′ The minimum cost path from vehicle node τ to i

[0077] t tra : Total task transmission delay

[0078] t com : Total delay of task calculation

[0079] The remaining available bandwidth resources of physical link e

[0080] b e : Total bandwidth resources of physical link e

[0081] The remaining available computing resources of vehicle i

[0082] Vehicle i is mission vehicle i * Allocated task computing resources

[0083] The technical solution of the present invention is described as follows:

[0084] 1. The cost w of each physical link e in the vehicle network e

[0085] The calculation method is shown in formula (1):

[0086]

[0087] In formula (1), represents the remaining available bandwidth resources of physical link e, b e represents the total bandwidth resource of the physical link e, b represents the task transmission bandwidth, T represents the task tolerance delay, t i,i′ represents the duration of the communication link between vehicle i and vehicle i′;

[0088] 2. Duration t of the communication link between vehicle i and vehicle i′ i,i′

[0089] The method is obtained by formula (2):

[0090]

[0091] In formula (2), x i with y i , x i′ with y i′ Represent the position coordinates of vehicles i and i′ respectively, v i With v i′ denote the speeds of vehicles i and i′, θ i and θi′ Denote the driving direction angles of vehicles i and i′, v i cosθ i With v i′ cosθ i′ denote the horizontal speeds of vehicles i and i′, v i sinθ i With v i′ sinθ i′ denote the vertical speeds of vehicles i and i′, respectively, and r denotes the effective communication range of the vehicle;

[0092] 3. Node selection probability ρ of vehicle i i

[0093] The calculation method is shown in formula (3):

[0094]

[0095] In formula (3), β i represents the shared weight factor, The remaining available computing resources for vehicle i The ratio of the total computing resources of vehicle i represents the normalized remaining available computing resources of vehicle i;

[0096] 4. Vehicle i is mission vehicle i * Allocated task computing resources

[0097] The calculation method is shown in formula (4):

[0098]

[0099] 5. Task offloading completion delay t

[0100] The calculation method is shown in formula (5):

[0101] t=t tra +t com (5)

[0102] In formula (5), t tra represents the total delay of task transmission, t com It represents the total delay of task calculation, and the calculation method is shown in formula (6):

[0103]

[0104] 6. Fitness Q of SFC deployment decision {A, B, C}

[0105] The calculation method is shown in formula (7):

[0106]

[0107] In formula (7), and They represent the normalized computing resources and normalized bandwidth resources required for task offloading, represents the normalized task offloading completion delay, 0≤α1≤1, 0≤α2≤1, 0≤α3≤1;

[0108] 7. Normalized computing resources required for task offloading

[0109] The calculation method is shown in formula (8):

[0110]

[0111] In formula (8), represents the total computing resources of vehicle i;

[0112] 8. Normalized computing resources required for task offloading

[0113] The calculation method is shown in formula (9):

[0114]

[0115] In formula (9), E represents the set of all physical links in the vehicle network;

[0116] 9. Normalized task offloading completion delay

[0117] The calculation method is shown in formula (10):

[0118]

[0119] 10. Sub-algorithm 1: Construct and update SFC mapping decision

[0120] 1) Initialize the temporary set I′=I, Temporary variable τ=i * , counting variables k=0, l=0;

[0121] 2) Let k = k + 1. If k ≤ |F|, jump to step 3). Otherwise, jump to step 7.

[0122] 3) Add the vehicles with SFC k-th VNF type instance and the idle vehicles that are not instantiated in set I′ to set I″, if Jump to step 4), otherwise, jump to step 8);

[0123] 4) For each vehicle i in the set I″, calculate the minimum cost path from vehicle node τ to i And remove the nodes that do not have the minimum cost path from the set I″;

[0124] 5) If Update the node mapping probability ρ of each vehicle i in the set I″ i , and according to the probability distribution {ρ i | i∈I″ Randomly select vehicle i from I″ and jump to step 6); otherwise, jump to step 8);

[0125] 6) Add vehicle i as the kth VNF mapping node to the node mapping decision A, and add the path Add the vehicle i as the lth virtual link to the link mapping decision B, set τ = i, l = l + 1, delete vehicle i from the set I′, and jump to step 2);

[0126] 7) Output SFC mapping decision {A, B};

[0127] 8) The algorithm ends.

[0128] 11. Sub-algorithm 2: Construct and update SFC resource allocation decision

[0129] 11) According to the node mapping decision A, the SFC mapping nodes are sequentially added to the temporary ordered set I′. According to the link mapping decision B, the bandwidth b required by the virtual link is added to the SFC resource allocation decision C, and the total task transmission delay t on the offload path is obtained. tra , where t tra is the cumulative transmission delay of task data through each physical link on the offloading path, and the counting variable k is set to 0;

[0130] 12) Allocate the basic computing resources c0 required for VNF instantiation to each vehicle i in the set I′ that does not have a corresponding VNF instance, and update the remaining available computing resources

[0131] 13) Let k = k + 1. If k ≤ |I′|, jump to step 14). Otherwise, jump to step 15).

[0132] 14) According to the remaining computing resources of the k-th vehicle i in the set I′ Given the task data volume d and task complexity ω, calculate the task computing resources required by the k-th VNF on vehicle i Skip to step 13);

[0133] 15) According to Calculate the task offloading completion delay t. If t>T, jump to step 16). Otherwise, jump to step 17.

[0134] 16) Calculate the remaining resources based on the vehicle The value of will sort the elements in the set I′ in descending order. If the remaining available computing resources of the first car i in the set I′ make Jump to step 15), otherwise, jump to step 18);

[0135] 17) Output SFC resource allocation decision C;

[0136] 18) The algorithm ends.

[0137] A method for offloading network tasks of vehicles in complex road conditions based on SFC, the specific implementation method of which includes the following steps:

[0138] Step 1: According to vehicle i * The task offloading request is proposed to initialize the optimal deployment fitness Q of the service function chain SFC * =0, counting variable h=0;

[0139] Step 2: Let h = h + 1. If h ≤ H, where H represents the maximum number of SFCs required to search for task offloading in the entire vehicle set I, jump to step 3. Otherwise, jump to step 6.

[0140] Step 3: Based on the ordered set F of virtual network functions (VNFs) required for task offloading, call sub-algorithm 1 to build and update the node and link mapping decision {A, B} of the SFC. If successful, jump to step 4; otherwise, jump to step 2.

[0141] Step 4: Based on the SFC mapping decision {A, B}, call sub-algorithm 2 to construct and update the resource allocation decision C. If successful, jump to step 5; otherwise, jump to step 2.

[0142] Step 5: Based on the SFC deployment decision {A, B, C}, calculate the corresponding deployment fitness Q. If Q * ≤Q, let Q * =Q, optimal SFC deployment decision {A * ,B * ,C *}={A,B,C}, jump to step 2, otherwise, jump to step 2;

[0143] Step 6: Output the optimal SFC deployment strategy * ,B * ,C *};

[0144] Step 7: The algorithm ends.

[0145] The systems, devices, modules, or units described in the above embodiments may be implemented by computer chips or entities, or by products having certain functions. A typical implementation device is a computer. Specifically, the computer may be, for example, a personal computer, a laptop computer, a cellular phone, a camera phone, a smartphone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or a combination of any of these devices.

[0146] Computer-readable media includes permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. The information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer-readable media does not include transitory computer-readable media (transitory media), such as modulated data signals and carrier waves.

[0147] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0148] The above embodiments should be understood as merely illustrating the present invention and not as limiting the scope of protection of the present invention. After reading the contents of the present invention, technicians may make various changes or modifications to the present invention, and these equivalent changes and modifications also fall within the scope defined by the claims of the present invention.

Claims

1. A method for offloading network tasks of vehicles in complex road conditions based on SFC, characterized in that: The following steps are involved:

101. According to vehicle i * The task offloading request is proposed to initialize the optimal deployment fitness Q of the service function chain SFC * =0, counting variable h=0; 102. Let h = h + 1. If h ≤ H, where H represents the maximum number of SFCs required to search for task offloading in the entire vehicle set I, jump to step 103. Otherwise, jump to step 106.

103. Build and update the node and link mapping decision {A, B} of the SFC based on the ordered set F of virtual network functions (VNFs) required for task offloading. If successful, jump to step 104; otherwise, jump to step 102.

104. Build and update resource allocation decision C based on the SFC mapping decision {A, B}. If successful, jump to step 105; otherwise, jump to step 102.

105. According to the SFC deployment decision {A, B, C}, calculate the corresponding deployment fitness Q. If Q * ≤Q, let Q * =Q, optimal SFC deployment decision {A * ,B * ,C * }={A,B,C}, jump to step 102, otherwise, jump to step 102; 106. Output the optimal SFC deployment strategy {A * ,B * ,C * }; 107. End; The step 103 constructs and updates the node and link mapping decision {A, B} of the SFC, specifically including the following steps: 1) Initialize the temporary set I′=I, Temporary variable τ=i * , counting variables k=0, l=0; 2) Let k = k + 1. If k ≤ |F|, jump to step 3). Otherwise, jump to step 7. 3) Add the vehicles with SFC k-th VNF type instance and the idle vehicles that are not instantiated in set I′ to set I″, if Jump to step 4), otherwise, jump to step 8); 4) For each vehicle i in the set I″, calculate the minimum cost path from vehicle node τ to i And remove the nodes that do not have the minimum cost path from the set I″; 5) If Update the node mapping probability ρ of each vehicle i in the set I″ i , and according to the probability distribution {ρ i | i∈I″ Randomly select vehicle i from I″ and jump to step 6); otherwise, jump to step 8); 6) Add vehicle i as the kth VNF mapping node to the node mapping decision A, and add the path Add the vehicle i as the lth virtual link to the link mapping decision B, set τ = i, l = l + 1, delete vehicle i from the set I′, and jump to step 2); 7) Output SFC mapping decision {A, B}; 8) The algorithm ends; The method for constructing and updating the resource allocation decision C in step 104 includes the following steps: 11) According to the node mapping decision A, the SFC mapping nodes are sequentially added to the temporary ordered set I′. According to the link mapping decision B, the bandwidth b required by the virtual link is added to the SFC resource allocation decision C, and the total task transmission delay t on the offload path is obtained. tra , where t tra is the cumulative transmission delay of task data through each physical link on the offloading path, and the counting variable k is set to 0; 12) Allocate the basic computing resources c0 required for VNF instantiation to each vehicle i in the set I′ that does not have a corresponding VNF instance, and update the remaining available computing resources 13) Let k = k + 1. If k ≤ |I′|, jump to step 14). Otherwise, jump to step 15). 14) Based on the remaining available computing resources of the k-th vehicle i in the set I′ Given the task data volume d and task complexity ω, calculate the task computing resources required by the k-th VNF on vehicle i Skip to step 13); 15) According to Calculate the task offloading completion delay t. If t>T, jump to step 16). Otherwise, jump to step 17. 16) Based on the remaining available computing resources of the vehicle The value of sorting the elements in set I′ in descending order, if the remaining available computing resources of the first car i in set I′ make Jump to step 15), otherwise, jump to step 18); 17) Output SFC resource allocation decision C; 18) The algorithm ends; The calculation method of the fitness Q of the SFC deployment decision {A, B, C} in step 105 is shown in formula (7): In formula (7), and They represent the normalized computing resources and normalized bandwidth resources required for task offloading, represents the normalized task offloading completion delay, 0≤α1≤1, 0≤α2≤1, 0≤α3≤1, where, The calculation method is shown in formulas (8), (9), and (10): In formula (8), represents the total computing resources of vehicle i. In formula (9), E represents the set of all physical links in the vehicle network.

2. The SFC-based complex road condition vehicle network task offloading method according to claim 1 is characterized in that: In step 4), the minimum cost path from vehicle node τ to i is calculated The methods specifically include: According to the cost w of each physical link e in the vehicle network e The calculation method is shown in formula (1). The minimum cost path algorithm is used to calculate the minimum cost path from vehicle node τ to i. In formula (1), represents the remaining available bandwidth resources of physical link e, b e represents the total bandwidth resource of the physical link e, b represents the task transmission bandwidth, T represents the task tolerance delay, t i,i′ represents the duration of the communication link between vehicle i and vehicle i′, t i,i′ The value of is calculated by formula (2): In formula (2), r represents the effective communication range of the vehicle, x i with y i , x i′ with y i′ Represent the position coordinates of vehicles i and i′, v i With v i′ denote the speeds of vehicles i and i′, θ i and θ i′ Denote the driving direction angles of vehicles i and i′, v i cosθ i With v i′ cosθ i′ denote the horizontal speeds of vehicles i and i′, v i sinθ i With v i′ sinθ i′ are the vertical velocities of vehicles i and i′ respectively.

3. The SFC-based complex road condition vehicle network task offloading method according to claim 1 is characterized in that: The node mapping probability ρ of each vehicle i in step 5) i The calculation method is shown in formula (3): In formula (3), β i represents the shared weight factor, is the remaining available computing resources of vehicle i The ratio of the total computing resources of vehicle i represents the normalized remaining available computing resources of vehicle i.

4. The SFC-based complex road condition vehicle network task offloading method according to claim 1 is characterized in that: The task computing resources required by the k-th VNF on vehicle i in step 14) The calculation method is shown in formula (4): d and ω represent the task data volume and task complexity respectively.

5. The SFC-based complex road condition vehicle network task offloading method according to claim 1 is characterized in that: The calculation method of the task offloading completion delay t in step 15) is shown in formula (5): t=t tra +t com (5) In formula (5), t tra represents the total delay of task transmission, t com It represents the total delay of task calculation, and the calculation method is shown in formula (6): d and ω represent the task data volume and task complexity respectively.

6. An electronic device, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory and executable on the processor. When the processor executes the program, the method for unloading complex road condition vehicle network tasks based on SFC as claimed in any one of claims 1 to 5 is implemented.

7. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the SFC-based complex road condition vehicle network task unloading method as claimed in any one of claims 1 to 5 is implemented.

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