CN109905251B - Network management method, apparatus, electronic device and storage medium - Google Patents

Abstract

Embodiments of the present invention provide a method, apparatus, electronic device and storage medium for implementing global network management based on SDN. The method is applied to an SDN controller, the SDN controller belongs to an SDN controller cluster, and each SDN controller in the SDN controller cluster is respectively connected to a distributed database, and is also connected to a plurality of switches respectively to form a network domain; A switch is connected to at least two SDN controllers; the network control method includes acquiring first topology information between switches in a network domain; acquiring second topology information between switches in the network domain where other SDN controllers in the SDN controller cluster are located from a distributed database ; Determine global network topology information according to the first topology information and the second topology information; and control each switch in the network domain to perform data forwarding based on the global network topology information. Therefore, the embodiment of the present invention expands the scale of the network topology, realizes the synchronous update of the global topology information, and requires less performance of the distributed database.

Description

Network management method, apparatus, electronic device and storage medium

technical field

The present invention relates to the technical field of network management, and in particular, to a network management method, apparatus, electronic device and storage medium.

Background technique

In recent years, the traditional network architecture has been insufficient to meet people's needs due to its complex management and lack of flexibility.

In order to meet people's demand for flexibility and simplicity of network management, the concept of SDN (Software Defined Network, Software Defined Network) has emerged. The core idea of the SDN concept is software programmability. Based on the concept of SDN, OpenFlow (a network protocol) network without a hierarchical network control method is often used in network applications.

Currently, in the existing OpenFlow network, only one SDN controller is usually used to perform centralized network management on all switches in the network. For example, suppose there are 1500 switches and an SDN controller in an OpenFlow network. The 1,500 switches will generate more than 100,000 data flows per second, and an SDN controller can only handle about 30,000 data flows, which makes it impossible to set up enough switches when deploying the OpenFlow network. , the global network topology scale is affected. Therefore, the existing OpenFlow network has the defect of small scale of the global network topology because an SDN controller is used to discover the global network topology to manage the switches.

SUMMARY OF THE INVENTION

The purpose of the embodiments of the present invention is to provide a network management method, apparatus, electronic device and storage medium, so as to solve the technical problem of how to expand the scale of the global network topology.

In order to achieve the above purpose, in the first aspect, the following technical solutions are provided:

A global network management method based on a software-defined network SDN, the method is applied to an SDN controller, the SDN controller belongs to an SDN controller cluster, and each SDN controller in the SDN controller cluster is respectively connected to a distributed database , and the SDN controllers are respectively connected with a plurality of interconnected switches to form a network domain;

The method includes:

Obtain the first topology information between switches in the network domain where it is located;

Acquire, from the distributed database, second topology information between switches in the network domain where other SDN controllers in the SDN controller cluster are located;

A global network topology is determined according to the first topology information and the second topology information.

Optionally, the step of acquiring the first topology information between switches in the network domain where the self is located includes:

Send topology information requests to switches in its own network domain;

Respectively receive the port information sent by each switch for the topology information request and the port information of the switch connected to it;

According to the received port information, the first topology information between switches in the network domain where the self is located is obtained.

Optionally, after the step of acquiring the first topology information between switches in the network domain where the self is located, the method includes:

Sending the first topology information to the distributed database.

Optionally, the step of acquiring the second topology information between switches in the network domain where other SDN controllers in the SDN controller cluster are located from the distributed database includes:

receiving a topology information update notification sent by the distributed database; wherein, the topology information update notification is sent by the distributed database when receiving the second topology information sent by the other SDN controllers;

Acquire second topology information between switches in the network domain where the other SDN controllers in the SDN controller cluster are located from the distributed database according to the topology information update notification.

Optionally, the method further includes:

According to the global network topology, each switch in the network domain where the self is located is controlled to perform data forwarding.

Optionally, the step of controlling each switch in the network domain where the self is located to perform data forwarding according to the global network topology includes:

A flow table is generated according to the global network topology, and the flow table is sent to each switch in the network domain where the self is located to control each switch in the network domain where the self is located to perform data forwarding.

Optionally, each switch in the network domain where the self is located includes multiple provider edge switches;

The step of generating a flow table according to the global network topology includes:

According to the global network topology, calculate the paths between the plurality of provider edge switches according to a predetermined algorithm;

A flow table containing the paths is generated.

Optionally, the step of calculating paths between the multiple provider edge switches according to a predetermined algorithm according to the global network topology includes:

receiving a data packet sent by the switch in the network domain where the self is located;

Parse the data packet to obtain the destination MAC address;

According to the global network topology and the destination MAC address, paths between the plurality of provider edge switches are calculated according to a predetermined algorithm.

Optionally, the method further includes:

receiving a network connection request sent by a switch in another network domain other than the network domain where it is located; wherein the network connection request is sent by a switch in the other network domain when the SDN controller of the other network domain fails;

According to the network connection request, a network connection is established with the switches in the other network domains.

In order to achieve the above purpose, in the second aspect, the following technical solutions are also provided:

A global network management device based on software-defined network SDN, the device is applied to an SDN controller, the SDN controller belongs to an SDN controller cluster, and each SDN controller in the SDN controller cluster is respectively connected to a distributed database , and the SDN controllers are respectively connected with a plurality of interconnected switches to form a network domain;

The device includes:

a first obtaining module, configured to obtain the first topology information between switches in the network domain where it is located;

A second obtaining module, configured to obtain, from the distributed database, second topology information between switches in the network domain where other SDN controllers in the SDN controller cluster are located;

A determining module, configured to determine a global network topology according to the first topology information and the second topology information.

Optionally, the first acquisition module includes:

a first sending unit, configured to send topology information requests to switches in the network domain where it is located;

a first receiving unit, configured to respectively receive the port information sent by each switch in response to the topology information request and the port information of the switch connected to it;

A first obtaining unit, configured to obtain the first topology information between switches in the network domain where the self is located according to the received port information.

Optionally, the device further includes:

A sending module, configured to send the first topology information to the distributed database.

Optionally, the second acquisition module includes:

A second receiving unit, configured to receive a topology information update notification sent by the distributed database; wherein, the topology information update notification is when the distributed database receives the second notification sent by the other SDN controller. Sent when topology information;

A second obtaining unit, configured to obtain the second topology information between switches in the network domain where the other SDN controllers in the SDN controller cluster are located from the distributed database according to the topology information update notification.

Optionally, the device further includes:

A control module, configured to control each switch in the network domain where the self is located to perform data forwarding according to the global network topology.

Optionally, the control module is specifically configured to generate a flow table according to the global network topology, send the flow table to each switch in the network domain where the self is located, and control the switches in the network domain where the self is located to perform data forwarding. .

Optionally, each switch in the network domain where the self is located includes multiple provider edge switches;

The control module includes:

a calculation unit, configured to calculate paths between the plurality of provider edge switches according to a predetermined algorithm according to the global network topology;

A generating unit for generating a flow table including the path.

Optionally, the computing unit includes:

a receiving subunit, configured to receive the data packet sent by the switch in the network domain where the self is located;

A parsing subunit for parsing the data packet to obtain a destination MAC address;

A calculation subunit, configured to calculate paths between the plurality of provider edge switches according to a predetermined algorithm according to the global network topology and the destination MAC address.

Optionally, the device further includes:

A receiving module, configured to receive a network connection request sent by a switch in another network domain other than the network domain where it is located; wherein, the network connection request is generated by the switch in the other network domain at the SDN controller of the other network domain Sent when there is a failure;

The establishing module is configured to establish a network connection with the switches in the other network domains according to the network connection request.

In order to achieve the above purpose, in the third aspect, the following technical solutions are also provided:

An electronic device including a processor and a memory;

the memory for storing computer programs;

The processor is configured to implement the method steps described in the first aspect when executing the program stored in the memory.

In order to achieve the above purpose, in the fourth aspect, the following technical solutions are also provided:

A computer-readable storage medium stores a computer program in the computer-readable storage medium, and when the computer program is executed by a processor, implements the method steps of the first aspect.

Embodiments of the present invention provide a method, apparatus, electronic device and storage medium for implementing global network management based on SDN. The network control method is applied to an SDN controller, the SDN controller belongs to an SDN controller cluster, and each SDN controller in the SDN controller cluster is respectively connected to a distributed database, and is also connected to a plurality of switches respectively to form a network domain ; The network control method comprises: acquiring first topology information between switches in a network domain where one is located; acquiring from a distributed database second topology information between switches in a network domain where other SDN controllers in the SDN controller cluster are located; according to the first topology information and the second topology information to determine the global network topology.

In the embodiment of the present invention, by adopting the above technical solution, the switches are controlled through the SDN controller cluster, and each SDN controller is connected to a plurality of interconnected switches in a network domain. Each SDN controller in the SDN controller cluster Not only the first topology information in the network domain where it is located, but also the second topology information in the network domain where other SDN controllers are located through the distributed database, so that each SDN controller can obtain the global network topology of the entire network. The scale of the network topology is enlarged, and the infinite expansion of the scale of the network topology can be realized. Moreover, the step of obtaining the second topology information in the network domain where other SDN controllers are located through the distributed database also realizes the synchronous update of the global topology information. In addition, in the embodiment of the present invention, the SDN controller obtains topology information from the distributed database, and does not involve related information such as path calculation, flow table delivery, etc.; The performance requirements are small, and the network performance is improved, thereby overcoming the defect of the SDN control performance bottleneck existing in the prior art.

Other features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or will be manifested by practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the description, claims and drawings.

Of course, it is not necessary for any product or method of the present invention to achieve all of the advantages described above at the same time.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to these drawings without creative efforts.

1 is a schematic diagram of a logical layered architecture of an SDN controller according to an embodiment of the present invention;

2 is a schematic flowchart of an SDN-based global network management method according to an embodiment of the present invention;

3 is a schematic diagram of a network topology structure according to an embodiment of the present invention;

FIG. 4 is a schematic flowchart of obtaining first topology information between switches in the network domain where oneself is located according to an embodiment of the present invention;

5 is a schematic flowchart of obtaining from a distributed database the second topology information between switches in the network domain where other SDN controllers in the SDN controller cluster are located according to an embodiment of the present invention;

6 is a schematic flowchart of a step of controlling each switch in the network domain where it is located to perform data forwarding according to the global network topology based on the embodiment shown in FIG. 2 according to an embodiment of the present invention;

7 is a schematic flowchart of generating a flow table according to a global network topology according to an embodiment of the present invention;

8 is a schematic flowchart of calculating paths between multiple provider edge switches according to a predetermined algorithm according to a global network topology according to an embodiment of the present invention;

9 is a schematic diagram of a process of maintaining a global network topology according to a switch role according to an embodiment of the present invention;

10 is a schematic diagram of a process of maintaining a global network topology according to a switch role according to another embodiment of the present invention;

11 is a schematic structural diagram of an SDN-based global network management apparatus according to an embodiment of the present invention;

12 is a schematic structural diagram of a first acquisition module according to an embodiment of the present invention;

13 is a schematic structural diagram of an SDN-based global network management apparatus according to another embodiment of the present invention;

14 is a schematic structural diagram of a second acquisition module according to an embodiment of the present invention;

15 is a schematic structural diagram of a control module according to an embodiment of the present invention;

16 is a schematic structural diagram of a computing unit according to an embodiment of the present invention;

FIG. 17 is a schematic structural diagram of an electronic device according to an embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

The following is a detailed description of the terms involved in this article:

A link is a connection path between any connected nodes in a network; for example, a connection path between two switches.

A path refers to a path from a source node to a destination node in a network; a path can contain one or more links; in this context, it can refer to a path between provider edge switches.

SDN: It is a network architecture, which mainly separates the control plane and data plane of network devices through the OpenFlow protocol, so as to realize the control of network traffic.

OpenFlow network: it includes a switch and a Controller (controller); wherein, the switch is preferably an OpenFlowSwitch (Open Flow Switch). OpenFlowSwitch is the core component of the entire OpenFlow network, including flow table, secure channel and OpenFlow protocol, and mainly manages the forwarding of the data layer. Among them, the secure channel is the interface connecting the switch and the controller; the OpenFlow protocol is used to describe the standard of the information used in the interaction between the controller and the switch, and the interface standard of the controller and the switch. OpenFlowSwitch has one or more FlowTable (flow table), and only forwards data packets according to the flow table. The generation, maintenance and distribution of FlowTable are implemented by Controller. Here, FlowTable does not refer to IP quintuple (IP source address, IP destination address, protocol number, source port, destination port), but covers almost all network fields of Layer 2 to Layer 7 networks. Every keyword in the FlowTable can be wildcarded. The operator of the network can decide what granularity of flow to use. For example, if the operator only needs to route data packets based on the destination IP, then only the IP destination address field in the FlowTable can be valid, and the others are all wildcards. The flow direction of data packets in traditional networks is artificially specified. Although switches and routers have control, they do not have the concept of data flow, and only perform packet-level exchanges. In OpenFlow networks, the Controller replaces routing and manages all data packets. The transmission path in the network to realize the function of the control layer.

FIG. 1 exemplarily shows a schematic diagram of a logical layered architecture of an SDN controller (also called an OpenFlow controller). The structure shown in Figure 1 is generally divided into three layers, namely the application layer, the control plane layer and the data plane layer. Among them, the control plane layer and the data plane layer are based on the same physical network. The data plane layer, as the bottom layer, mainly includes devices such as switches; the switch is preferably a physical machine that supports the OpenFlow protocol or a software-implemented virtual switch (for example, OpenFlowSwitch, OpenFlow switch), which is responsible for receiving flow table rules from the controller and forwarding them. Network traffic. The control plane layer includes an OpenFlow controller; the OpenFlow controller is used to discover the global topology of the lower-layer switches, and then issue corresponding flow table rules according to specific services and upper-layer application logic to control the switches to forward data traffic. The application layer is based on some specific business applications based on the OpenFlow controller. For example, it can include virtual networks, traffic engineering and multiple floodlight applications, which are used to abstract a logical virtual network, functional user configuration and use, thereby The user does not need to care about the structure of the specific physical network at the lower layer, and it is easy to perform networking and connection services.

The existing OpenFlow network has the defect of small scale of the global network topology because an SDN controller is usually used to discover the global network topology to manage the switches. For example, in the existing solution using one master and multiple backups, multiple controllers read and write the same database for saving relevant network topology information based on the OpenFlow protocol. In this solution, only one master controller writes to the database at the same time; the backup controller can only read network topology information from the database. Thus, network scale support is limited by the capabilities of the SDN controller. Therefore, this scheme has the defect of not supporting large-scale network topology due to only one controller at the same time.

In view of this, in order to solve the technical problem of how to expand the scale of the global network topology, an embodiment of the present invention provides a global network management method based on a software-defined network SDN, which is applied to an SDN controller. The SDN controller belongs to the SDN controller cluster, and the SDN Each SDN controller in the controller cluster is connected to a distributed database, and each SDN controller is connected to a plurality of interconnected switches to form a network domain; as shown in Figure 2, the SDN-based global network management method includes the following Steps S200 to S220. in:

S200: Acquire first topology information between switches in the network domain where the self is located.

In this step, the SDN controller may obtain the first topology information among the multiple switches in the network domain where it is located. Wherein, each SDN controller in the SDN controller cluster can only manage and control some switches in the entire network. For example, the SDN controller can be any commercial or open source controller such as a FloodLight controller (flood light controller), an OpenDayLight controller (an open source controller). Among them, the FloodLight controller has a simplified structure and adopts a modular design mode, which is easy to add and develop upper-layer virtual network applications. The SDN controller runs on a server (for example, an X86 architecture server), and performs data flow processing such as topology discovery, flow table delivery, and data packet reporting processing on the server. Each SDN controller can manage a certain number of switches through the IP addresses and port numbers of the switches.

The switch is preferably an OpenFlow switch supporting the OpenFlow protocol. The port of the switch can be used to send and receive control packets, and can also be used to send and receive data packets. The switch can maintain a flow table locally.

The first topology information may include, but is not limited to, the IP addresses and port numbers of each switch.

Table 1 exemplarily shows the first topology information. The information in Table 1 indicates that the first switch is connected to the second switch through port 1; the second switch is connected to the third switch through port 5.

Table 1

Switch that starts forwarding packets The port number connected next switch first switch number 1 second switch second switch Number 5 third switch

FIG. 3 exemplarily shows a schematic diagram of a network topology. The network topology shown in Figure 3 is a three-layer network topology of the data center. It includes a distributed database 30 , a network domain 31 and a network domain 32 . The network domain 31 includes the SDN controller 311 and the switch 3111 , the switch 3121 , the switch 3122 , the switch 3131 , and the switch 3132 . The network domain 32 includes an SDN controller 321 and a switch 3211 , a switch 3221 , a switch 3222 and a switch 3231 . Switch 3111 , switch 3211 , switch 3121 , switch 3122 , switch 3221 and switch 3222 form a full mesh (full mesh) connected network to provide non-blocking data forwarding from the access layer network equipment to the intermediate aggregation layer network. The access layer is used to provide workstation access services to the local network segment. The aggregation layer refers to the intermediary layer between the network access layer and the core layer. The core layer refers to the network backbone network layer. The SDN controller 311 and the SDN controller 321 may constitute an SDN controller cluster. The distributed database 30 can be implemented by an open source database, and the distributed database 30 can provide a distributed lock function to ensure the orderly and efficient reading and writing of data of all SDN controller nodes in the SDN controller cluster. As shown in FIG. 3 , the SDN controller 311 obtains the topology information between the switch 3111 , the switch 3131 , the switch 3132 , the switch 3131 and the switch 3132 in the network domain 31 ; the SDN controller 321 obtains the SDN controller 321 and the switch 3211 in the network domain 32 , the topology information between switch 3221, switch 3222 and switch 3231.

Specifically, in some optional embodiments, as shown in FIG. 4 , this step may include the following steps S201 to S203. in:

S201: Send topology information requests to switches in the network domain where the network domain is located.

In practical applications, the switch is configured with the IP (Internet Protocol) address of the SDN controller. The switch actively establishes a connection with the SDN controller. After the connection is established, the SDN controller sends a topology information request to the switch in its own network domain.

Following the example shown in FIG. 3 , the SDN controller 311 may send a topology information request to each switch in the network domain 31 .

S202: Receive the port information sent by each switch in response to the topology information request and the port information of the switch connected thereto respectively.

The port information may be the port number of the switch, for example, No. 2, No. 5, and so on.

In practical applications, after the switch receives the topology information request, it sends its own port information and the port information of the connected switch to the SDN controller.

Following the example shown in FIG. 3 , taking the switch 3131 in the network domain 31 as an example, the SDN controller 311 receives its own port number and the port numbers used by the switch 3121 and the switch 3122 sent by the switch 3131 .

S203: According to the received port information, obtain first topology information between switches in the network domain where the self is located.

In this step, after receiving the port information, a topology map may be drawn according to the connection relationship between the ports of each switch to form the first topology information.

Taking Table 1 as an example, the information in Table 1 indicates that the first switch is connected to the second switch through port 1; the second switch is connected to the third switch through port 5. Through the topology information, topology information between the first switch and the second switch can be obtained.

In some optional embodiments, after step S200, the SDN-based global network management method may further include:

The first topology information is sent to the distributed database.

In this step, each SDN controller can send the obtained topology information to the distributed database, so as to realize the updating of the topology information stored in the distributed database.

S210: Acquire, from the distributed database, second topology information between switches in the network domain where other SDN controllers in the SDN controller cluster are located.

For the description of the second topology information, reference may be made to the description of the first topology information in this document, and details are not repeated here.

The embodiment of the present invention not only obtains the first topology information between switches in the network domain where the self is located, but also obtains the second topology information between switches in the network domain where other SDN controllers in the SDN controller cluster are located through this step, so as to obtain the global network topology .

In some optional embodiments, as shown in FIG. 5 , step S210 may specifically include step S211 and step S212. in:

S211: Receive a topology information update notification sent by the distributed database; wherein, the topology information update notification is sent by the distributed database when it receives the second topology information sent by other SDN controllers.

In the specific implementation process, each SDN controller monitors the topology information update of the distributed database in real time. When the topology information in the distributed database is updated, the distributed database notifies each SDN controller, and then each SDN controller receives the topology information update notification sent by the distributed database.

Following the example shown in FIG. 3 , if the SDN controller 311 sends topology information to the distributed database 30 ; the distributed database 30 sends a topology information update notification to the SDN controller 321 .

S212: Acquire second topology information between switches in the network domain where other SDN controllers in the SDN controller cluster are located from the distributed database according to the topology information update notification.

As an example, after each SDN controller receives the update notification, it obtains, from the distributed database, topology information sent by other SDN controllers to the distributed database, thereby realizing synchronization of global topology information.

S220: Determine the global network topology according to the first topology information and the second topology information.

In this step, according to the obtained topology information between switches in the own network domain and the topology information between switches in the network domain where other SDN controllers are located, obtained from the distributed database synchronization, the relationship between the ports of each switch in each network domain in the entire network can be obtained. According to the connection relationship between them, a topology map can be spelled out to determine the global topology.

Taking Figure 3 as an example, switch 3111, switch 3211, switch 3121, switch 3122, switch 3221 and switch 3222 can use DC Core (Data Center Core, core switch) with 32╳40G interface; switch 3131, switch 3132 and switch 3231 can use 48╳10G+4╳40G TOR (top-of-the-cabinet switch); under this topology, using 48 DC Cores and 128 TORs can provide 6144 10G access ports with 3:1 convergence. Connect the access port to an X86 server, and the X86 server runs a Vswitch (virtual switch) and an SDN controller for forwarding. If a server with 24 cores and 128G of memory is configured, this embodiment can provide a network topology with a scale of 100,000. Compared with the prior art using one SDN controller, the scale of the global network topology is enlarged.

In the embodiment of the present invention, each SDN controller in the SDN controller cluster is used to obtain the topology information in the respective network domains, and then the topology information obtained by the other SDN controllers is obtained through the distributed database, thereby realizing the global network topology. 's discovery.

In the existing solution of using a distributed database to discover the network topology, the distributed database is used to store information such as network topology, flow table, and SDN controller status such as OpenDayLight in a unified manner, that is, all status information is stripped out and stored in a distributed database. in the database. Although this solution solves the bottleneck of scale through a distributed database, this solution stores the network topology and all state information in a unified database. Therefore, this scheme not only increases the logic complexity of the controller, but also has high performance requirements for the distributed database. For example, if the flow table information that changes in real time cannot be stored and updated in time, it will cause confusion in the network path. cause network failure.

In addition, in the existing solution that some controllers use the two-stage submission method, the controllers are divided into two layers. Among them, the controllers of the lower layer manage some OpenFlow switches respectively, the upper layer is the central controller, manages each controller in the lower layer, and receives network topology information from the lower layer controllers, thereby discovering the global topology. In this solution, the lower-level controller can process requests such as partial flow table issuance, and only requests that cannot be processed are forwarded to the upper-level central controller for processing. Therefore, when the number of controllers in the lower layer increases, the central controller will become a performance bottleneck, resulting in poor network performance.

However, in the embodiment of the present invention, a complete distributed controller solution is proposed, which also uses a unified distributed database to access state information. However, since only topology information is synchronized between the SDN controller and the distributed database, The information amount of the topology information is small and stable, and will not change, and logic such as path calculation and flow table delivery is not introduced into the distributed database; therefore, the embodiment of the present invention has small performance requirements on the distributed database, and is implemented by This also ensures good global topology synchronization real-time and also improves network performance.

In some optional embodiments, based on any of the foregoing embodiments, as shown in FIG. 6 , the SDN-based global network management method may further include:

S230: Control each switch in the network domain where it is located to perform data forwarding according to the global network topology.

According to the global network topology control, this embodiment controls each switch in its own network domain to forward the data packet, and finally forwards the data packet to the destination server.

In a specific implementation process, multiple OpenFlow switches and SDN controllers may form a data plane; then, data packets are forwarded through the data plane.

In some optional embodiments, on the basis of the above-mentioned embodiments, according to the global network topology, the step of controlling each switch in the network domain where it is located to perform data forwarding specifically includes:

The flow table is generated according to the global network topology, and the flow table is sent to each switch in the network domain where it is located to control the data forwarding of each switch in the network domain where it is located.

In this embodiment, the flow table includes multiple flow table entries; each flow table entry may include one or more matching fields, specifically, may include header fields, destination MAC (Media Access Control, Media Access Control layer) ) address, source MAC address, destination IP address, source IP address, TCP port number/UDP port number, commands, etc. Among them, the instruction is used to indicate which port to forward the packet through. Of course, the flow entry may also include a counter and the like. The counter is used to count the number of times the flow entry is hit.

As an example, in this step, when the flow table is sent to each switch in the own network domain, the flow table entries may be sent to each switch in ascending order according to the number of hops between the switch and itself on the path.

In addition, those skilled in the art should be able to understand that, in order to enable the switch to forward data packets, an initial flow table may be sent to the switch. Specifically, the flow table can be obtained by separating the control plane and the data plane. For example, an OpenFlow switch connects to the control plane based on the LLDP (Link Layer Discovery Protocol, Link Layer Discovery Protocol) and STP (Spanning Tree Protocol, Spanning Tree Protocol) protocols, that is, through the forwarding table generated by the above protocols to implement various OpenFlow control messages 's forwarding. The OpenFlow switch sends a flow table request to the SDN controller; after the SDN controller receives the flow table request, it sends the flow table entry to the OpenFlow switch through the control plane; the OpenFlow switch adds the flow table entry to its own local maintenance after receiving the flow table entry to obtain the initial flow table.

In some optional embodiments, on the basis of the above-mentioned embodiments, each switch in its own network domain includes multiple provider edge switches; as shown in FIG. 7 , the step of generating the flow table according to the global network topology includes the following step S231 and step S232. in:

S231: Calculate paths between multiple provider edge switches according to a predetermined algorithm according to the global network topology.

The predetermined algorithm may be, for example, a minimum path algorithm, an optimal path algorithm, a critical path algorithm, etc., but is by no means limited thereto.

The provider edge switch (ie, provider edge switch, PE device for short) may be a switch with a small load, for example, a switch with a single port of 10 Gb throughput. The PE device can be, for example, an ordinary switch. The PE device is connected to the server.

Corresponding to the above-mentioned provider edge switch, this paper also defines a provider switch (ie, provider switch, P device for short), which may be a switch with a large load, for example, a switch with a single port of 40Gb throughput. The P device can act as an intermediate node and is not connected to the server.

S232: Generate a flow table including paths.

In this embodiment, the path calculation and the flow table are calculated and stored by each SDN controller independently, and the requirement for the distributed database is small, which improves the network performance.

In some optional embodiments, on the basis of the foregoing embodiments, as shown in FIG. 8 , according to the global network topology, the step of calculating paths between multiple provider edge switches according to a predetermined algorithm may specifically include steps S2311 to S2311 to Step S2313. in:

S2311: Receive the data packet sent by the switch in the network domain where the self is located.

The switch sends the packet to the SDN controller when at least the following conditions occur:

Case 1: The switch receives a packet that does not match any flow entry;

When the above situation occurs, the switch sends the data packet to the SDN controller in its own network domain to obtain a matching flow table.

Case 2: The switch receives the data packet, but does not receive the flow table sent by the SDN controller.

The above situation includes the situation that the switch does not match the flow table within a predetermined time (for example, 3 minutes, 5 minutes), and deletes the unmatched flow table. When the second situation occurs, the switch sends the packet to the SDN controller to obtain a flow table that matches the packet.

S2312: Parse the data packet to obtain the destination MAC address.

S2313: Calculate paths between multiple provider edge switches according to a predetermined algorithm according to the global network topology and the destination MAC address.

The predetermined algorithm may be, for example, a minimum path algorithm, an optimal path algorithm, a critical path algorithm, etc., but is by no means limited thereto.

To facilitate network management and path calculation, the embodiments of the present invention divide switches into provider edge switches and provider switches, that is, divide switches into PE (provider edge, provider edge) roles and P (provider, provider) roles , referred to as PE equipment and P equipment, respectively. The role of the switch applies to the SDN controller and is transparent to the physical switch. The SDN controller maintains the topology within the network domain based on roles. Specifically, the P device only acts as an intermediate node in the network topology, and does not act as a source or destination node for path calculation; when the network topology is discovered, the link between the PE devices is determined to be an illegal link and is ignored. Therefore, in this step, paths between PE devices are calculated according to, for example, a minimum path algorithm, an optimal path algorithm, and a critical path algorithm.

In practical applications, the above-mentioned P roles and PE roles can maintain the corresponding relationship between switches and roles through the SwitchRoleManager (switch role manager). Users can view the role information of all switches, or set/delete the role configuration of a switch through the Restful API (Representational State Transfer API).

The process of maintaining the global network topology according to the switch role according to the embodiment of the present invention will be described in detail below with reference to FIG. 9 with a specific embodiment. In this embodiment, an access switch in a network domain is used as an example.

When a new switch in the network domain is connected and connected to the SDN controller, the SDN controller identifies the switch; determines the role of the switch according to the predetermined correspondence between the switch and the role; links the link of the switch whose role is determined Lines (also called Links), topology information is sent to a distributed database.

Specifically, as shown in FIG. 9 , the SDN controller may include a topology manager, a switch role manager, a domain topology manager, and a global topology manager.

When there is a switch connected to the network, perform the following steps:

Step a1: The topology manager sends a switch connection controller notification to the switch role manager;

Step a2: The switch role manager sets the role of the switch when the role information exists, and sends the set role information to the domain topology manager;

Step a3: The domain topology manager adds the switch to the local controller topology; the domain topology manager obtains the link related to the switch and sends it to the topology manager; adds the legal Link line to the topology, and initializes the link weight , delete the illegal Link line; send the updated topology information to the global topology manager, after the update, calculate the path, pre-delivery the flow table, and update the link weight;

Step a4: The global topology manager sends the update information of the distributed database to the domain topology manager for other SDN control to calculate paths between multiple provider edge switches according to a predetermined algorithm according to the updated global network topology information.

Similarly, when the switch is disconnected from the SDN controller in the network domain where the switch is located, the processing process is similar to that of the switch access, which is not repeated here.

The process of maintaining the global network topology according to the switch role according to the embodiment of the present invention will be described in detail below with reference to FIG. 10 with a specific embodiment. This embodiment takes the link state change as an example.

When the link status in the network topology changes, the domain topology manager is triggered to perform related processing. When a new link line is added, the local topology will be updated, and then the information will be updated to the distributed database, and the global topology will be synchronized with other SDN controllers. When the link line is disconnected, it will detect whether the link line exists in the local topology; if it exists, the operations such as path calculation and flow table delivery will be updated; then, the link line will be deleted and updated to the distributed database.

As shown in Figure 10, the topology manager sends a Link add/disconnect message to the domain topology manager; when the link is valid, the domain topology manager adds the link to the topology, initializes the link weight to 1(), and then sends the link to the The global topology manager sends an instruction to update the distributed database; if the link is illegal, the domain topology manager will mark the link as a warning and will not handle it. If the link exists in the topology, the domain topology manager deletes the link from the topology, and then sends the updated distributed database information to the global topology manager; if the link does not exist in the topology, the domain topology manager deletes the link from the alarm link Delete the link and perform operations such as related path calculation and flow table delivery. When a link line is disconnected, it will detect whether the link line exists in the local topology. If it exists, it will update the path calculation and flow table distribution and other operations, and then delete the link line and update it to the distributed database to For other SDN controllers to calculate paths between multiple provider edge switches according to the updated global network topology information according to a predetermined algorithm.

In the prior art, only one SDN controller is used to centrally manage the network. If this SDN controller fails and goes down, since there is no backup SDN controller to take over the failed SDN controller, the entire network cannot work normally. Therefore, the prior art suffers from a single point of failure.

In view of the above-mentioned defects in the prior art, in some optional embodiments, on the basis of the embodiment shown in FIG. 4 , the SDN-based global network management method further includes the following steps b1 and b2.

Step b1: receiving network connection requests sent by switches in other network domains other than the network domain where the network domain is located; wherein, the network connection requests are sent by switches in other network domains when the SDN controller of other network domains fails;

In the specific implementation process of this step, the IP addresses of at least two SDN controllers may be configured in the switch, so that the switch can receive management from the at least two SDN controllers.

For example, if an OpenFlow switch is connected to the first SDN controller and the second SDN controller, configure the IP addresses of the first SDN controller and the second SDN controller in the OpenFlow switch, and make the OpenFlow switch connect with the first SDN controller and the second SDN controller. The first SDN controller is in the same network domain. In this way, the OpenFlow switch and the second SDN controller are in different network domains. When the first SDN controller fails, the OpenFlow switch is configured with the IP address of the second SDN controller. Therefore, at this time, the OpenFlow switch can connect to the second SDN controller, that is, to the second SDN controller. Send a network connection request. The second SDN controller receives the network connection request sent by the OpenFlow switch in other network domains.

Step b2: According to the network connection request, establish network connections with switches in other network domains.

Following the above example, after receiving the network connection request, the second SDN controller establishes a network connection with the OpenFlow switch to manage the OpenFlow switch. The network connection may be, for example, a TCP (Transmission Control Protocol) connection.

In this embodiment, the switch is connected to at least two SDN controllers; therefore, when one of the SDN controllers fails and goes down and cannot work normally, the switch can network with other SDN controllers that do not fail and go down. connection to maintain normal operation. Therefore, compared with the scheme using one master and multiple backups, this embodiment overcomes the defect of a single point of failure, and the technical scheme provided by the embodiment of the present invention can make the network not limited by the performance of one SDN controller. It overcomes the defect of performance bottleneck, thereby improving the processing speed of the network and the scale of the network topology.

To sum up, in this embodiment of the present invention, by adopting any of the above technical solutions, the switches are controlled through the SDN controller cluster, and each SDN controller is connected to multiple switches in one network domain. An SDN controller not only obtains the first topology information in its own network domain, but also obtains the second topology information of the network domain where other SDN controllers are located through a distributed database, so that each SDN controller can obtain the global network of the entire network. Therefore, the scale of the network topology is expanded, and the infinite expansion of the scale of the network topology can be realized. Moreover, the step of obtaining the second topology information in the network domain where other SDN controllers are located through the distributed database also realizes the synchronous update of the global topology information. In addition, in the embodiment of the present invention, the SDN controller obtains topology information from the distributed database, and does not involve related information such as path calculation, flow table delivery, etc.; The performance requirements are small, and the network performance is improved, thereby overcoming the defect of the SDN control performance bottleneck existing in the prior art.

The existing OpenFlow network has the defect of small scale of the global network topology because an SDN controller is usually used to discover the global network topology to manage the switches. Thus, network scale support is limited by the capabilities of the SDN controller. Therefore, in order to solve the technical problem of how to expand the scale of the global network topology, an embodiment of the present invention provides a software-defined network SDN-based global network management apparatus, which can execute the above method embodiments. The device is applied to an SDN controller. The SDN controller belongs to an SDN controller cluster. Each SDN controller in the SDN controller cluster is respectively connected to a distributed database, and each SDN controller is respectively connected to a plurality of interconnected switches to form a network. domain; as shown in Figure 11, the SDN-based global network management device includes:

The first obtaining module 111 is configured to obtain the first topology information between switches in the network domain where the self is located;

The second obtaining module 112 is configured to obtain, from the distributed database, second topology information between switches in the network domain where other SDN controllers in the SDN controller cluster are located;

The determining module 113 is configured to determine the global network topology according to the first topology information and the second topology information.

In this embodiment, the switches are controlled through the SDN controller cluster, and each SDN controller is connected to multiple switches in one network domain. Each SDN controller in the SDN controller cluster not only obtains its own location through the first obtaining module 111 The first topology information in the network domain, and the second topology information of the network domain where other SDN controllers are located from the distributed database is also obtained through the second obtaining module 112, so that the global network topology of the entire network can be obtained through the determining module 113. The scale of the network topology is enlarged, and the infinite expansion of the scale of the network topology can be realized. Moreover, the step of acquiring the second topology information in the network domain where other SDN controllers are located from the distributed database by the second acquiring module 112 also realizes the synchronous update of the global topology information. In addition, in the embodiment of the present invention, the SDN controller obtains topology information from the distributed database, and does not involve related information such as path calculation, flow table delivery, etc.; The performance requirements are small, and the network performance is improved, thereby overcoming the defect of the SDN control performance bottleneck existing in the prior art.

In some optional embodiments, as shown in FIG. 12 , the first acquisition module includes:

The first sending unit 121 is configured to send topology information requests to switches in the network domain where it is located;

The first receiving unit 122 is configured to respectively receive the port information sent by each switch in response to the topology information request and the port information of the switch connected to it;

The first obtaining unit 123 is configured to obtain, according to the received port information, the first topology information between switches in the network domain where the user is located.

In some optional embodiments, as shown in FIG. 13 , the SDN-based global network management apparatus may further include:

The sending module 114 is configured to send the first topology information to the distributed database.

In some optional embodiments, as shown in FIG. 14 , the second acquisition module specifically includes:

The second receiving unit 141 is configured to receive the topology information update notification sent by the distributed database; wherein, the topology information update notification is sent by the distributed database when it receives the second topology information sent by other SDN controllers;

The second obtaining unit 142 is configured to obtain the second topology information between switches in the network domain where other SDN controllers in the SDN controller cluster are located from the distributed database according to the topology information update notification.

In some optional embodiments, the SDN-based global network management apparatus may further include:

The control module is used to control each switch in the network domain where it is located to perform data forwarding according to the global network topology.

In some optional embodiments, the control module is specifically configured to generate a flow table according to the global network topology, send the flow table to each switch in the network domain where it is located, and control each switch in the network domain where it is located to perform data forwarding.

In some optional embodiments, each switch in the network domain where it is located includes multiple provider edge switches;

As shown in Figure 15, the control module specifically includes:

a calculation unit 151, configured to calculate paths between multiple provider edge switches according to a predetermined algorithm according to the global network topology;

The generating unit 152 is configured to generate a flow table including paths.

In some optional embodiments, as shown in FIG. 16 , the computing unit specifically includes:

The receiving subunit 161 is used to receive the data packet sent by the switch in the network domain where it is located;

The parsing subunit 162 is used to parse the data packet to obtain the destination MAC address;

The calculation subunit 163 is configured to calculate paths between multiple provider edge switches according to a predetermined algorithm according to the global network topology and the destination MAC address.

In some optional embodiments, the SDN-based global network management apparatus may further include:

The receiving module is used to receive network connection requests sent by switches in other network domains other than its own network domain; wherein, the network connection requests are sent by switches in other network domains when the SDN controller in other network domains fails;

The establishment module is used for establishing network connection with switches in other network domains according to the network connection request.

For the description of the embodiment of the SDN-based global network management apparatus, reference may be made to the description of the foregoing SDN-based global network management method embodiment, which will not be repeated here.

Based on the same technical idea as the method embodiment, the embodiment of the present invention further provides an electronic device, as shown in FIG. 17 , including a processor 171 and a memory 172;

a memory 172 for storing computer programs;

The processor 171 is configured to implement the method steps described in the foregoing embodiments of the SDN-based global network management method when executing the program stored in the memory 172 .

Of course, those skilled in the art should understand that the above embodiments may also include a communication interface and a communication bus, and these obviously modified or equivalently replaced embodiments should also be included within the protection scope of the present invention.

The communication bus mentioned in the above electronic device may be a peripheral component interconnect standard (Peripheral Component Interconnect, PCI) bus or an Extended Industry Standard Architecture (Extended Industry Standard Architecture, EISA) bus or the like. The communication bus can be divided into an address bus, a data bus, a control bus, and the like. For ease of representation, only one thick line is shown in FIG. 17, but it does not mean that there is only one bus or one type of bus.

The above-mentioned communication interface is used for communication between the above-mentioned electronic device and other devices.

The above-mentioned memory 172 may include random access memory (Random Access Memory, RAM), and may also include non-volatile memory (non-volatile memory, NVM), such as at least one disk storage. Optionally, the memory may also be at least one storage device located away from the aforementioned processor.

The above-mentioned processor 171 may be a general-purpose processor, including a central processing unit (Central Processing Unit, CPU for short), a network processor (Ne twork Processor, NP), etc.; it may also be a digital signal processor (Digital Signal Processing, DSP), Application Specific Integrated Circuit (ASIC), Field-Programmable Gate Array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, and discrete hardware components.

The above electronic devices include but are not limited to smart phones, computers, personal digital assistants, wearable devices, and the like.

In this embodiment, by executing the program stored in the memory 172 by the processor 171, the switches are controlled through the SDN controller cluster, and each SDN controller is connected to multiple switches in one network domain, and the SDN controller cluster Each SDN controller in the SDN controller not only obtains the first topology information in its own network domain, but also obtains the second topology information of the network domain where other SDN controllers are located through the distributed database, so that each SDN controller can obtain the entire network. The global network topology, thus expanding the scale of the network topology, and can achieve unlimited expansion of the scale of the network topology. Moreover, the step of obtaining the second topology information in the network domain where other SDN controllers are located through the distributed database also realizes the synchronous update of the global topology information. In addition, in the embodiment of the present invention, the SDN controller obtains topology information from the distributed database, and does not involve related information such as path calculation, flow table delivery, etc.; The performance requirements are small, and the network performance is improved, thereby overcoming the defect of the SDN control performance bottleneck existing in the prior art.

Based on the same technical concept as the method embodiments, the embodiments of the present invention further provide a computer-readable storage medium. A computer program is stored in the computer-readable storage medium, and when the computer program is executed by the processor, the method steps described in the foregoing embodiments of the SDN-based global network management method are implemented.

The above-mentioned computer-readable storage medium may include, but is not limited to, random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), read only memory (ROM), programmable read only memory ( PROM), Erasable Programmable Read Only Memory (EPROM), Electrically Erasable Programmable Read Only Memory (EEPROM), Flash Memory (eg, NOR-type Flash or NAND-type Flash), Content Addressable Memory (CAM), Polymer memory (eg, ferroelectric polymer memory), phase change memory, bidirectional switching semiconductor memory, silicon-oxide-silicon nitride-silicon-oxide-silicon (SONOS) memory, Magnetic card or optical card, or any other suitable type of computer-readable storage medium.

In this embodiment, when the computer program is executed by the processor, the switches are controlled through the SDN controller cluster, and each SDN controller is connected to multiple switches in one network domain, and each SDN controller in the SDN controller cluster controls the switches. The controller not only obtains the first topology information in its own network domain, but also obtains the second topology information of the network domain where other SDN controllers are located through the distributed database, so that each SDN controller can obtain the global network topology of the entire network. This enlarges the scale of the network topology, and can realize the infinite expansion of the scale of the network topology. Moreover, the step of obtaining the second topology information in the network domain where other SDN controllers are located through the distributed database also realizes the synchronous update of the global topology information. In addition, in the embodiment of the present invention, the SDN controller obtains topology information from the distributed database, and does not involve related information such as path calculation, flow table delivery, etc.; The performance requirements are small, and the network performance is improved, thereby overcoming the defect of the SDN control performance bottleneck existing in the prior art.

It should be noted that, in this document, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any relationship between these entities or operations. any such actual relationship or sequence exists. Moreover, the terms "comprising", "comprising" or any other variation thereof are intended to encompass non-exclusive inclusion such that a process, method, article or device comprising a list of elements includes not only those elements, but also includes not explicitly listed or other elements inherent to such a process, method, article or apparatus. Without further limitation, an element qualified by the phrase "comprising a..." does not preclude the presence of additional identical elements in a process, method, article or apparatus that includes the element.

The various embodiments in this specification are described in a related manner, and each embodiment focuses on the differences from other embodiments, and the same and similar parts between the various embodiments can be referred to each other. In particular, for the apparatus embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and reference may be made to some descriptions of the method embodiments for related parts. The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims (14)

1. A global network management method based on software-defined network SDN, characterized in that the method is applied to an SDN controller, the SDN controller belongs to an SDN controller cluster, and each SDN controller in the SDN controller cluster are respectively connected with the distributed database, and the SDN controllers are respectively connected with a plurality of interconnected switches to form a network domain; The method includes: Obtain the first topology information between switches in the network domain where it is located; Acquire, from the distributed database, second topology information between switches in the network domain where other SDN controllers in the SDN controller cluster are located; determining a global network topology according to the first topology information and the second topology information; Each switch in the network domain where the self is located includes a plurality of provider edge switches; The method also includes: According to the global network topology, the paths between the plurality of provider edge switches are calculated according to a predetermined algorithm; the predetermined algorithm is used to calculate the paths between the provider edge switches; A flow table including the path is generated, and the flow table is respectively sent to each switch in the network domain where the self is located, and each switch in the network domain where the self is located is controlled to forward data. 2. The method according to claim 1, wherein the step of acquiring the first topology information between switches in the network domain where the self is located comprises: Send topology information requests to switches in its own network domain; Respectively receive the port information sent by each switch for the topology information request and the port information of the switch connected to it; According to the received port information, the first topology information between switches in the network domain where the self is located is obtained. 3. The method according to claim 1, wherein after the step of acquiring the first topology information between switches in the network domain where the self is located, the method comprises: Sending the first topology information to the distributed database. 4. The method according to claim 1, wherein the step of acquiring the second topology information between switches in the network domain where other SDN controllers in the SDN controller cluster are located from the distributed database comprises: receiving a topology information update notification sent by the distributed database; wherein, the topology information update notification is sent by the distributed database when receiving the second topology information sent by the other SDN controllers; Acquire second topology information between switches in the network domain where the other SDN controllers in the SDN controller cluster are located from the distributed database according to the topology information update notification. 5. The method according to claim 1, wherein the step of calculating the paths between the plurality of provider edge switches according to the global network topology according to a predetermined algorithm comprises: receiving a data packet sent by the switch in the network domain where the self is located; Parse the data packet to obtain the destination MAC address; According to the global network topology and the destination MAC address, paths between the plurality of provider edge switches are calculated according to a predetermined algorithm. 6. The method of claim 1, wherein the method further comprises: receiving a network connection request sent by a switch in another network domain other than the network domain where it is located; wherein the network connection request is sent by a switch in the other network domain when the SDN controller of the other network domain fails; According to the network connection request, a network connection is established with the switches in the other network domains. 7. A software-defined network SDN-based global network management device, wherein the device is applied to an SDN controller, the SDN controller belongs to an SDN controller cluster, and each SDN controller in the SDN controller cluster are respectively connected with the distributed database, and the SDN controllers are respectively connected with a plurality of interconnected switches to form a network domain; The device includes: a first obtaining module, configured to obtain the first topology information between switches in the network domain where it is located; A second obtaining module, configured to obtain, from the distributed database, second topology information between switches in the network domain where other SDN controllers in the SDN controller cluster are located; a determining module, configured to determine a global network topology according to the first topology information and the second topology information; Each switch in the network domain where the self is located includes a plurality of provider edge switches; The device also includes: a calculation unit, configured to calculate paths between the plurality of provider edge switches according to a predetermined algorithm according to the global network topology; the predetermined algorithm is used to calculate the paths between the provider edge switches; a generating unit for generating a flow table including the path; The second sending unit is configured to send the flow table to each switch in the network domain where the self is located, and control the switches in the network domain where the self is located to perform data forwarding. 8. The apparatus according to claim 7, wherein the first obtaining module comprises: a first sending unit, configured to send topology information requests to switches in the network domain where it is located; a first receiving unit, configured to respectively receive the port information sent by each switch in response to the topology information request and the port information of the switch connected to it; A first obtaining unit, configured to obtain the first topology information between switches in the network domain where the self is located according to the received port information. 9. The apparatus of claim 7, wherein the apparatus further comprises: A sending module, configured to send the first topology information to the distributed database. 10. The apparatus according to claim 7, wherein the second acquiring module comprises: A second receiving unit, configured to receive a topology information update notification sent by the distributed database; wherein, the topology information update notification is when the distributed database receives the second notification sent by the other SDN controller. Sent when topology information; A second obtaining unit, configured to obtain the second topology information between switches in the network domain where the other SDN controllers in the SDN controller cluster are located from the distributed database according to the topology information update notification. 11. The apparatus according to claim 7, wherein the computing unit comprises: a receiving subunit, configured to receive the data packet sent by the switch in the network domain where the self is located; A parsing subunit for parsing the data packet to obtain a destination MAC address; A calculation subunit, configured to calculate paths between the plurality of provider edge switches according to a predetermined algorithm according to the global network topology and the destination MAC address. 12. The apparatus of claim 7, wherein the apparatus further comprises: A receiving module, configured to receive a network connection request sent by a switch in another network domain other than the network domain where it is located; wherein, the network connection request is generated by the switch in the other network domain at the SDN controller of the other network domain Sent when there is a failure; The establishing module is configured to establish a network connection with the switches in the other network domains according to the network connection request. 13. An electronic device, comprising a processor and a memory; the memory for storing computer programs; The processor is configured to implement the method steps of any one of claims 1-6 when executing the program stored in the memory. 14. A computer-readable storage medium, wherein a computer program is stored in the computer-readable storage medium, and when the computer program is executed by a processor, the method steps of any one of claims 1-6 are implemented.

Images