CN111835843A

CN111835843A - Cloud system based on SDN (software defined network) Internet of vehicles

Info

Publication number: CN111835843A
Application number: CN202010631277.XA
Authority: CN
Inventors: 刘星宇; 杨雪芹; 潘若禹
Original assignee: Xian University of Posts and Telecommunications
Current assignee: Xian University of Posts and Telecommunications
Priority date: 2020-07-03
Filing date: 2020-07-03
Publication date: 2020-10-27

Abstract

The embodiment of the invention discloses a cloud system based on SDN (software defined networking), which comprises: the system comprises a global SDN control module, a local SDN controller module, a cloud center module, a fog server module, a middleware module and a bottom node module; the global SDN control module is used for managing service arrangement of a local SDN controller; the local area SDN controller module is used for distributing local network resources and controlling service requirements of all RSUs and terminal vehicles in the local area; the cloud center module is used for being responsible for overall resource management of the Internet of vehicles, including resource storage allocation, network management, security authentication and virtual management, and users can enjoy flexible and convenient services as required; the fog server module is used for being responsible for data processing and analysis of a local area; the middleware module is configured to connect the global SDN control module, the local SDN controller module, and the bottom node module.

Description

Cloud system based on SDN (software defined network) Internet of vehicles

Technical Field

The embodiment of the invention relates to the field of radio frequency integrated circuits, in particular to a cloud system based on SDN (software defined networking).

Background

With the continuous perfection of the architecture of the internet of vehicles and the continuous development of communication technology, people put forward higher requirements on vehicle application, and the network topology of the internet of vehicles is fast to update, the communication modes are diverse, the heterogeneity is converged, the interfaces are not uniform and standard, the utilization rate of network resources such as equipment and frequency spectrum is low, the flow is unbalanced, delay caused by high mobility and unreliable connection are caused, and the requirements form great challenges for the existing architecture and Quality of service (QoS).

However, when the vehicle is in a high-speed moving state or the number of vehicle nodes is too large, devices in many networks need to be configured separately, and the configuration speed often cannot keep up with the speed of the network change, thereby affecting the smoothness of the service, which may cause the situations of packet loss and network congestion, and affect the service experience of the user.

Disclosure of Invention

The embodiment of the invention provides a cloud system based on an SDN (software defined network), which can solve the problems of packet loss and network congestion.

In order to solve the technical problem, the embodiment of the invention adopts the following technical scheme:

in a first aspect of embodiments of the present invention, a hierarchical control software-based SDN cloud system for defining an SDN cloud is provided, where the SDN cloud system includes: the system comprises a global SDN control module, a local SDN controller module, a cloud center module, a fog server module, a middleware module and a bottom node module; the global SDN control module is used for managing service arrangement of a local SDN controller; the local area SDN controller module is used for distributing local network resources and controlling the service requirements of all RSUs and terminal vehicles in the local area; the cloud center module is used for being responsible for overall resource management of the Internet of vehicles, including resource storage allocation, network management, security authentication and virtual management, and a user can enjoy flexible and convenient services as required; the fog server module is used for processing and analyzing data of a local area; and the middleware module is used for connecting the global SDN control module, the local SDN controller module and the bottom node module.

In the embodiment of the application, the method and the device are suitable for mobile equipment networks moving at high speed, such as the Internet of vehicles and unmanned aerial vehicles. Under the deployment environment of cloud and SDN, the network is managed and controlled from a global and local two-stage view by utilizing the flexibility of SDN centralized management, so that the increase of global time delay caused by the rapid movement of vehicles can be reduced, and the stability and the connectivity of the network can be ensured; the cloud and fog two-stage resource management is also divided on the resource management layer, the cloud and fog two-stage resource management is respectively responsible for global and local resource management, local computing resources can be effectively utilized, global network burden is relieved, time delay is reduced, meanwhile, load forwarding and transferring can be carried out among the fog service nodes, pressure of a data center is relieved for a cloud center, and therefore quality of communication is guaranteed to the greatest extent.

Drawings

FIG. 1 is a diagram of a prior art cloud system of a vehicle networking;

FIG. 2 is a diagram of a Software Defined Networking (SDN) based cloud system architecture of the present invention;

fig. 3 is a functional diagram of a two-level SDN controlled vehicle networking cloud system of the present invention;

fig. 4 is a service supplementary unit module newly added to the LSDN of the present invention;

FIG. 5 is a middleware unit module of the present invention;

FIG. 6 is a GSDN new global policy auxiliary unit module according to the present invention;

FIG. 7 is a principal process of a vehicle node requesting service of the present invention;

fig. 8 is a task migration state transition diagram of the LSDN of the present invention.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The terms "first" and "second," and the like, in the description and in the claims of the embodiments of the present application are used for distinguishing between different objects and not for describing a particular order of the objects. For example, the first and second coupling lines, etc. are used to distinguish between different media files, rather than to describe a particular order of the media files.

In the description of the embodiments of the present application, the meaning of "a plurality" means two or more unless otherwise specified. For example, a plurality of elements refers to two elements or more.

The term "and/or" herein is an association relationship describing an associated object, and means that there may be three relationships, for example, a display panel and/or a backlight, which may mean: there are three cases of a display panel alone, a display panel and a backlight at the same time, and a backlight alone. The symbol "/" herein denotes a relationship in which the associated object is or, for example, input/output denotes input or output.

In the embodiments of the present application, words such as "exemplary" or "for example" are used to mean serving as an example, instance, or illustration. Any embodiment or design described herein as "exemplary" or "e.g.," is not necessarily to be construed as preferred or advantageous over other embodiments or designs. Rather, use of the word "exemplary" or "such as" is intended to present concepts related in a concrete fashion.

Currently, in the related art, the internet of vehicles cloud system mainly has the following 4 problems.

Problem 1, poor flexibility. The existing internet of vehicles generally adopts the existing IP network architecture, which causes great trouble to the mobility support of the network. Because the IP network is based on the forwarding of the destination address, when the vehicle moves at a high speed and the network topology changes frequently, many devices in the network need to be configured separately, and the configuration speed often cannot keep up with the network change speed, thereby affecting the smoothness of the service, which causes great troubles.

Problem 2, scalability is poor. The development of the internet of vehicles still lacks a uniform standard, and because different manufacturers and the consistency of vehicle-mounted software and hardware are lacked, the adopted processors, operating systems, sensing equipment and the like are all different, a certain gap exists in communication between vehicles, and even a piece of equipment is only suitable for one vehicle type. Maintenance of equipment often requires designated personnel as well. Especially, when new equipment or a communication protocol is added, the whole vehicle model and the whole set of equipment are required to be updated, and the wide-range deployment of the vehicle networking is seriously hindered.

Problem 3, quality of service is to be improved. With the progress of society, the scale of the internet of vehicles is continuously enlarged, the number of vehicles as nodes is also increased sharply, and the existing application service mode is challenged greatly. The increase of the nodes brings more data processing amount, for example, the environmental factors of node collection increase, the real-time requirement of the user on the vehicle-mounted service is higher, and the like, and the existing network architecture is faced with the situation that packet loss and network congestion often occur, which affects the service experience of the user.

Problem 4, isomerism problem. Compared with other types of wireless sensor networks, the current situation that multiple communication modes coexist in the internet of vehicles also increases the problem of heterogeneity, and each communication mode needs different network resources such as interfaces, equipment and frequency spectrums, which greatly challenges the existing network architecture. The existing network structure has certain defects in the aspects of meeting large-batch management, high-quality service, real-time application and the like, has various problems such as flexibility, expandability, mobility support, safety and the like, cannot adapt to the rapid development of the internet of vehicles, and is necessary to a new network structure and a new network technology suitable for dynamic network topology change.

In order to solve the problems in the related art, in the embodiment of the application, a Software Defined Network (SDN) is introduced into an internet of vehicles for management and control, and the management is further subdivided into two levels of control management, wherein a first level global SDN controller (GSDN) is placed on the top layer of the network, and the position of a second level local SDN controller (LSDN) is sunk to the lower layer, so that the global delay can be reduced; then, the resource management in the internet of vehicles is correspondingly divided into two stages, the first stage is a cloud center, the second stage is a fog server, the fog server is adopted instead of a cloud server with higher cost as a roadside cloud of the edge equipment, and the problems of resource waste and communication bottleneck caused by lack of a management mechanism in the existing internet of vehicles can be solved; and finally, interacting with a cloud center through a global SDN controller (GSDN), and interacting with a fog server through a local SDN controller (LSDN) to jointly fulfill the requirements of network control and resource management of the Internet of vehicles.

The specific scheme is that the whole car networking service area is also divided into two levels: the device comprises 1 global area and a plurality of local areas. The global area is responsible for management and control and resource scheduling of the whole internet of vehicles and interaction with the cloud center, the local area is responsible for management and control and resource scheduling of local vehicle users and interaction with local fog service nodes, and SDN controllers are configured in the global area and the local area. Software and hardware resources of road side infrastructures (RSUs, mobile vehicles, base stations and fog nodes) in the internet of vehicles can be virtualized into a resource pool through the NFV technology, so that a local SDN controller can centrally control local resources and can coordinate and distribute the local resources to other required vehicle nodes through the local fog computing technology to complete tasks; the global SDN controller manages coordination and control of resources among the local areas, coordination of a control layer is completed through reasonable service arrangement and network management among the local controllers, and a large amount of calculation and storage are handed to the cloud center of the global resource manager for management. The efficiency of the whole car networking is higher through two-stage management and control and two-stage resource management.

The Software Definition (SDN) vehicle networking Cloud system based on hierarchical control mainly comprises a global SDN controller module (GSDN), a local SDN controller module (LSDN), a Cloud center module, a Fog server module, a middleware module and a bottom node layer module 6 large module. The global controller module GSDN allocates network resources from a global view by utilizing the characteristic of centralized control of an SDN architecture, and leads the global; simultaneously the GSDN manages all local SDN controller (e.g., LSDN1 and LSDN2 in fig. 2) service orchestration; a local area SDN controller module (LSDN) also utilizes the characteristic of centralized control of an SDN architecture to allocate local network resources from a local view and control the service requirements of all RSUs and terminal vehicles in the area; the Cloud center module is responsible for overall resource management of the Internet of vehicles, and comprises resource storage allocation, network management, security authentication and virtual management, so that a user can enjoy flexible and convenient services according to requirements, and the optimization of service quality and energy efficiency is realized from a system level and an equipment level respectively; the Fog server module is used as a local data center and an edge computing point and is responsible for data processing and analysis of a local area, so that local computing resources are effectively utilized, and the burden of a global network is relieved; the middleware module completes interaction of the GSDN and the LSDN and arrangement management of each local fog server node, so that the purpose of load balancing is achieved, and the quality of service is expected to be guaranteed to the maximum extent.

In the Software Definition (SDN) vehicle networking cloud system based on hierarchical control, a global controller module GSDN has the following functions, and specific services of an application layer can be customized through programming; directly or indirectly wirelessly accessing each local controller module LSDN; managing the latest global view of the whole network topology and the service flow; and converting the network policy into a flow table rule in a specific switch according to the applied network policy, and issuing a flow table to the LSDN and the like. The GSDN can provide different network views for different application programs and customized different network states through the functions, and the mode is favorable for service expansion and service deployment of the whole Internet of vehicles.

In the Software Defined Network (SDN) cloud system based on hierarchical control, a local area SDN controller module LSDN has the following functions of controlling the topology of a local area and the latest view of service flow; providing a flow table rule for a switch in a service control module; interaction with the roadside equipment RSU and the vehicle on the bottom layer is undertaken; the method comprises the steps of (1) bearing resources of Fog mist server nodes for management and coordination; various ways to connect to a global controller (GSDN); sharing a data model between local controllers LSDN through intercommunication of an SDN east-west interface; the development and the deployment of local services are facilitated.

In the Software Definition (SDN) vehicle networking Cloud system based on hierarchical control, a Cloud center module consists of a high-performance server cluster and is a Cloud data center and a Cloud control center; the system can store and analyze a large amount of data collected by various terminal devices; and comprehensive and high-quality service can be provided for users through the deployment of the control center. The method is mainly used for improving the service quality and the computing capacity of the Internet of vehicles and is responsible for processing the requirements on resources.

According to the Software Defined Network (SDN) cloud system based on hierarchical control, the Fog server module comprises a personal computer, a mobile device, a lightweight server and the like, and can periodically collect the use conditions of computing resources of devices such as RSUs, vehicles and base stations in a region. When a service request enters the local network, the data volume required to be processed by each device and the data volume transmitted to the cloud end can be determined according to available resources, so that the local resource management function is realized.

According to the Software Definition (SDN) internet of vehicles cloud system based on hierarchical control, a bottom node layer module comprises roadside infrastructure (node units, communication base stations, cameras and the like), a vehicle cloud and devices such as mobile phones and computers of users. The existing isolated vehicles are divided into different regional collections in a bottom node according to a certain principle (within a certain radius range, within a certain block and the like) to form a vehicle cloud, vehicles in the same collection are communicated with one another through the vehicles to form an Adhoc network, computing resources, storage resources and spectrum resources are shared, and efficiency is improved.

The embodiment of the application provides an SDN-based cloud system of the Internet of vehicles, and in the cloud and SDN deployment environment, the flexibility of SDN centralized management is utilized to manage and control the network from a global and local two-stage view, so that the increase of global time delay caused by the rapid movement of vehicles can be reduced, and the stability and the connectivity of the network can be ensured; the cloud and fog two-stage resource management is also divided on the resource management layer, the cloud and fog two-stage resource management is respectively responsible for global and local resource management, local computing resources can be effectively utilized, global network burden is relieved, time delay is reduced, meanwhile, load forwarding and transferring can be carried out among the fog service nodes, pressure of a data center is relieved for a cloud center, and therefore quality of communication is guaranteed to the greatest extent.

The SDN-based car networking cloud system provided by the embodiment of the present application is described in detail below with reference to the accompanying drawings through specific embodiments and application scenarios thereof.

Fig. 1 is a structure diagram of an existing internet of vehicles cloud system, in which a general internet of vehicles cloud system is divided into three clouds, including a central cloud, a roadside access cloud, and a vehicle cloud from top to bottom, the central cloud is a large-scale cloud data center, the roadside access cloud is generally composed of a plurality of RSUs or base station devices, and is often set as a fog service node, and the vehicle cloud is a mobile phone, a computer, a vehicle-mounted device, and the like of a user to form an Adhoc network.

Fig. 2 is a structure diagram of a hierarchical Software Definition (SDN) -based cloud system of an internet of vehicles according to the present invention, in the existing cloud system of an internet of vehicles of fig. 1, two levels of SDN controllers are used to complete a control function of the entire internet of vehicles, a first level of SDN controller GSDN is deployed at a network top layer to control a global policy, and interacts with a cloud center of global resources to manage and control the global resources; the second level controller LSDN is deployed at various local centers, often administrative areas of the actual car networking, or divided according to the network fragmentation of the middleware, instead of on each RSU, each LSDN controlling multiple RSUs. Under the control of a two-level hierarchical SDN, each task of a vehicle node is not required to be uploaded to a first-level controller GSDN, but control management service is carried out through a second-level LSDN closest to the vehicle node, the control mode can reduce time delay and relieve the pressure of the first-level main controller, in addition, each local LSDN interacts with a respective Fog server to carry out calculation and storage of local resources, and the interaction between the GSDN and each LSDN is completed through a middleware.

Fig. 3 is a logic function diagram of a two-stage SDN-controlled vehicle networking cloud system of the present invention, which mainly includes three functional components, namely an LSDN, a middleware, and a GSDN, and these modules cooperate to complete the work.

In the LSDN module, all local devices (a drive test unit RSU, a base station, a vehicle, a mobile phone, a computer and the like) are virtualized into resources in a local network element unit, classified management is carried out through a local resource management unit, meanwhile, the use condition of the local resources is inquired in a Fog server node through a Fog interaction unit, the result is returned to a local service auxiliary unit, then the LSDN local service auxiliary unit is used for inquiring whether the local virtual resources can provide required service for the local vehicle, if yes, the network element devices (the RSU and the base station) providing service are arranged for the local service auxiliary unit through the local service arrangement management unit, and then a local centralized control unit sends a data processing task to the RSU or the vehicle to be served; otherwise, if the real-time position changes occur due to the movement of the vehicle, the service arrangement management is changed according to the GPS information of the vehicle, meanwhile, the state of the corresponding local resource management unit (comprising the Fog server node RSU and the base station) is modified, and the result is uploaded to the Fog server node.

In the GSDN module, a data collection unit collects network fragments of the middleware and virtual resource use conditions of the LSDN, service arrangement and updating are carried out in a service arrangement unit according to global load in a global resource management module, then a global strategy auxiliary unit inquires the global resource use conditions in a cloud center through cloud interaction, meanwhile, a strategy database similar to a secondary flow table is established by combining the conditions of the global service arrangement unit in the GSDN, the strategy database is issued to the middleware, and meanwhile, the real-time resource use conditions of the middleware and the LSDN are updated in the global resource management unit and are uploaded to the cloud center.

The middleware module has the main functions of completing the management and arrangement of virtual LSDN and Fog service nodes and the division (network fragmentation) of actual LSDN (administrative region), and completing the interaction of GSDN and LSDN and the real-time data update.

Fig. 4 details the main operation of the newly added local service supplementary module in the LSDN module. The local service auxiliary module is used for inquiring whether virtual resources in a local area (same LSDN) meet the service requirement of a local vehicle node. It is mainly divided into 5 units: the system comprises a resource manager, a task manager, a local centralized control unit, a fog node interaction unit and a safety unit.

The resource controller includes a local resource collector, a local resource database, and a local resource manager. The resource controller firstly collects the state information (including positioning, speed, direction, service type and the like) of the local vehicle and the current RSU1 through the local resource collector, meanwhile, the data is transmitted to the local resource database, filtering, storing and analyzing are carried out in the database, whether the local resource is lack of resources or not is reported to the local resource manager, the local resource manager records the current RSU1 resource lack state of the current vehicle and the service type to be processed, and the result is transmitted to the task manager module;

the task manager includes a traffic collector of LSDNs, a control module, and a set of RSUs that can provide services. If the task manager receives the current RSU1 resource shortage sent by the resource control unit, the service collector starts to search the available RSU states (position, CPU, transmission rate, free memory and the like) around the vehicle node, then sends the result to the control module, the control module selects and provides the RSU and LSDN for service, caches the RSU and LSDN which can be served, and sends the information to the local centralized control unit; the local centralized control unit selects a proper RSU2, then the RSU2 replaces the vehicle to carry out communication, the communication is finished, the communication result is returned to the vehicle node of the mobile vehicle needing service, and the used RSU2 is released; in the process, the interaction with the fog server is performed for 2 times, the resource shortage state of the current RSU1 is transmitted to the fog server in a local resource database of the resource manager for the first time, the state of the selected serviceable RSU2 is uploaded to the fog server for the second time, the RSU2 service is completed, and the state of the RSU2 in the fog server is also updated in real time after the resources are released. Simultaneously interacting with the middleware; the security unit is used to secure the communication between the RSU node and the vehicle device.

Fig. 5 is a middleware module, which includes a virtualized LSDN, an LSDN/fog management unit, a network fragment detection unit, and an LSDN arrangement unit. The network fragmentation detection unit collects LSDNs where vehicle clouds actually exist and the use conditions of the LSDNs, or each LSDN reports the use conditions of the LSDNs, and the use conditions of the LSDNs are monitored in real time; the LSDN served by the vehicle can be changed due to the rapid movement of the vehicle or conflict with the LSDN arranged by the GSDN, the LSDN arranging unit in the middleware rearranges the using condition of the LSDN according to the actual condition or algorithm, so that the LSDN served by the vehicle is changed and migrated, the LSDN is selected for serving according to the arranging result of the LSDN, and the interaction with the GSDN and the LSDN is completed at the same time.

Fig. 6 is a detailed diagram of a global policy assistance unit module in the GSDN module, which is mainly used when a mobile vehicle moves fast and provides service resources to migrate from LSDN1 to LSDN2, and the global policy assistance unit adjusts the service resources in real time according to the usage of each local LSDN collected by the GSDN data collection unit module, in combination with the usage of global resources in a cloud center, and also considering the situation of global service pre-arrangement in the GSDN. The global policy auxiliary unit module is divided into 4 units: the system comprises a global resource manager, a task control manager, a cloud center interaction unit and a security unit.

The global resource manager comprises a global resource collector, a global resource database and a global resource manager. The global resource manager unit firstly collects all virtual resource information stored from each fog server through a global resource collector, transmits the data to a global resource database, compares, filters and analyzes the state use information data of the network fragment (region fragment) and the LSDN of the middleware collected by the data collection unit of the GSDN in the database, removes redundancy, sends the results (to-be-selected LSDN and RSU) to a control module in the task manager, and simultaneously stores the results in the global resource manager;

the task control unit comprises a service arranging unit, a control module and a flow table unit. If the task control unit receives the information sent by the resource management unit, the service arrangement plan can be changed in real time according to the global resource load condition inquired from the cloud center, then the result is sent to the control module, a reasonable flow table rule is established by the control module, then network division and LSDN arrangement are adjusted according to the global task load, and the network division and LSDN arrangement are updated to the cloud center for storage, and then the information is sent to the middleware module;

fig. 7 shows the main processes of requesting a service when a position change occurs in a mobile vehicle:

the first step is as follows: under the condition that the vehicle nodes can provide resources in the same local LSDN, namely the vehicle nodes originally provide services through the RSU1 under the LSDN1, the RSU providing the services is changed into the RSU2 under the same LSDN1 due to the movement of the vehicle, and at the moment, a resource allocation request is sent to the local LSDN1, and the local LSDN1 controller provides quick service allocation capable of replacing the RSU2 of the vehicle for the vehicle nodes according to the flow table strategy. If the local LSDN1 lacks resources, it is first determined whether to upload the task to the primary controller GSDN, and if it needs to migrate from the current LSDN1 to another new LSDN, the service assistance module starts to find the appropriate LSDN around to prepare for service, and sends the result to the middleware.

The second step is that: the middleware firstly inquires the use state of the old LSDN from a fog server of the LSDN module, inquires the state and the idle condition of the new LSDN which can be served from the GSDN and the cloud center, comprehensively compares the states to obtain the optimal new LSDN, then waits for the selected new LSDN to carry out task migration, and records the state of the current new LSDN in the resource management of the LSDN module and the GSDN module.

The third step: the new LSDN gives a response, and simultaneously the RSU resource under the new LSDN which the vehicle node can migrate to is determined and informed by the new LSDN, and the service state of the LSDN is marked in the management module.

The fourth step: the vehicle checks whether a migration decision is made to the RSU of the new LSDN and, if a migration decision is made, sends a migration request and establishes a connection.

The fifth step: the vehicle confirms the migration.

And a sixth step: the vehicle node sends the task to the selected RSU while the task migration flag is performed at the middleware module of the LSDN.

The seventh step: and starting to execute the task by the new LSDN module, and returning a task result to the vehicle node.

Eighth step: when the task is finished, the service connection between the vehicle and the RSU served by the vehicle is disconnected, the resource of the RSU is released, and the RSU returns to the service arrangement to wait for the next service.

Here, if it is required that a vehicle node can migrate a task to multiple LSDNs around it, once migration of RSUs under the same LSDN occurs, the result is uploaded to a fog server of the same LSDN and stored; if the migration task occurs under different LSDNs, not only the LSDN state of the cloud center needs to be updated, but also the RSU states of 2 LSDNs need to be updated.

Fig. 8 details the LSDN task migration state transition diagram. The local LSDN can provide service for local vehicles at the beginning, the migration to the new LSDN is not needed, and the migration task is in a closing state; if the local LSDN is lack of resources, the LSDN task migration is in a preparation state, the LSDN reports to the middleware to start searching other LSDNs which can serve the LSDN, a proper LSDN is found and connected successfully, the migration state is started, and then the task is migrated to a new LSDN; if the connection is unsuccessful, returning to a migration ready state; if no task is migrated, the migration is in a suspended state; when a new task exists, the migration returns to the starting state; when the LSDN connection is disconnected, then the migration returns to the ready state; when the resources local to the vehicle node are restored, then the migration returns to the off state.

The invention has the following advantages:

the flexibility is good: the SDN two-stage control is adopted, the control plane and the data plane are decoupled, all the physical equipment is virtualized, the physical equipment does not need to be configured independently, and the network management is controlled by software, so that the network can react to various states quickly, and the task of processing the vehicle nodes can be processed better and faster.

The expansibility is good: if a plurality of vehicle nodes, RSUs, base stations and other devices are added, the original relation among resources does not need to be changed, the devices are virtualized into resources in a resource pool, and management and resource allocation of the network are controlled by software, so that the network expansibility is greatly improved for the whole network.

The time delay is low: the function of the local controller is moved down, meanwhile, the fog service nodes on the edge are used in a fusion mode, so that if the vehicle nodes move in the local area, the vehicle nodes do not need to be uploaded to a high-level controller, the cost of the transmission process is reduced, the time delay is reduced, and the resource utilization rate is increased.

The resource utilization rate is high: all the software and hardware devices are virtualized into resources in the resource pool, and tasks among the resources can be mutually migrated, so that load balance is achieved, and the utilization rate of all the resources is improved.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A layered control software-based SDN (software defined networking) cloud system, the SDN cloud system comprising: the system comprises a global SDN control module, a local SDN controller module, a cloud center module, a fog server module, a middleware module and a bottom node module;

the global SDN control module is used for managing service arrangement of a local SDN controller; the local area SDN controller module is used for distributing local network resources and controlling service requirements of all RSUs and terminal vehicles in the local area; the cloud center module is used for being responsible for overall resource management of the Internet of vehicles, including resource storage allocation, network management, security authentication and virtual management, and users can enjoy flexible and convenient services as required; the fog server module is used for being responsible for data processing and analysis of a local area; the middleware module is configured to connect the global SDN control module, the local SDN controller module, and the bottom node module.

2. The SDN internet of vehicles cloud system of claim 1, wherein the bottom node layer modules comprise node units, communication base stations, cameras, vehicle clouds and terminal devices; the bottom node layer module is used for dividing a vehicle group into different region sets according to a certain principle to form a vehicle cloud, vehicles in the same set form an Adhoc network through vehicle-to-vehicle communication, and computing resources, storage resources and spectrum resources are shared.

3. The SDN internet cloud system of claim 1 or 2, wherein the local SDN controller module is configured to query local resource usage by the fog server module and return the result to the local SDN controller module, and then query whether the local vehicle can be provided with the required service with the local SDN controller module.

4. The SDN internet of vehicles cloud system of claim 3, wherein the local SDN controller module is specifically configured to, if the local SDN controller module can provide a required service for a local vehicle, arrange a network element device providing the service for the local vehicle through the local service orchestration management unit, and then the local centralized control unit sends a data processing task to the RSU or the vehicle to be served.

5. The SDN internet of vehicles cloud system of claim 3, wherein the local SDN controller module is specifically configured to, if the local SDN controller module is unable to provide required services for the local vehicle, change service orchestration management according to GPS information of the vehicle if a real-time location change occurs due to movement of the vehicle, while modifying a state of the corresponding local SDN controller module, and uploading the result to the fog server node.

6. The SDN internet of vehicles cloud system of claim 1, wherein the global SDN control module is configured to collect network fragmentation of middleware and local SDN controller module usage, update service orchestration according to global load in the global SDN control module, and then use resource usage of the global SDN control module in a cloud center module.

7. The SDN-based cloud system of claim 6, wherein the global SDN control module is further configured to build a policy database similar to a secondary flow table in combination with a situation of a global service orchestration unit in the global SDN control module, issue the policy database to middleware, and update real-time resource usage of the policy database in the global SDN control module and upload the real-time resource usage to the cloud center module.