CN109617778B

CN109617778B - Method, device and system for realizing cross-domain two-layer network service

Info

Publication number: CN109617778B
Application number: CN201811395151.6A
Authority: CN
Inventors: 熊志伟; 陈晓晨; 周明宇
Original assignee: Xi'an Baicaibang Network Technology Co ltd
Current assignee: Xi'an Baicaibang Network Technology Co ltd
Priority date: 2018-11-22
Filing date: 2018-11-22
Publication date: 2021-05-18
Anticipated expiration: 2038-11-22
Also published as: CN109617778A

Abstract

The embodiment of the invention provides a method, a device and a system for realizing cross-domain two-layer network service, wherein the method comprises the following steps: the method comprises the steps that a centralized controller obtains link state information of a plurality of tunnel servers, wherein the tunnel servers are distributed and deployed in a plurality of local area networks, and each tunnel server is connected with a local gateway of the corresponding local area network; the centralized controller determines transmission path information of a message to be transmitted according to the link state information of the tunnel servers; and the centralized controller sends the transmission path information of the message to be transmitted to the local gateway of the corresponding local area network, so that the local gateway sends the message to be transmitted to the tunnel server of the local area network receiving the message to be transmitted according to the transmission path information determined by the centralized controller. According to the method and the system, the optimal path can be automatically selected to transmit the message by adopting the plurality of tunnel servers and the local gateways which are distributed and deployed in the plurality of local area networks, so that the network quality is improved, and the user experience is enhanced.

Description

Method, device and system for realizing cross-domain two-layer network service

Technical Field

The present invention relates to the field of communications, and in particular, to a method, an apparatus, and a system for implementing a cross-domain two-layer network service.

Background

A large enterprise and a medium enterprise usually have a plurality of cross-regional office centers, and these cross-regional office centers generally need to be able to access each other like a local area network, that is, there is a cross-regional large two-tier networking requirement.

In order to implement large two-layer networking, a network element is usually added at a network exit of each office center, a tunnel is established between the network element and network element devices at network exits of other office centers, and two-layer messages (i.e., data frames of a data link layer) in an enterprise are transmitted on the tunnel. For example, when an enterprise uses LTE mobile technology for networking, the network element device may be a CPE (Customer Premise Equipment). Fig. 1 shows a conventional implementation method of L2 service (i.e. data link layer service), as shown in fig. 1, there is usually a centralized LNS (L2TP Network Server, Network Server using two-layer channel protocol), one end of the LNS is connected to the local area Network of the enterprise headquarters, and the other end is connected to the CPEs of the respective office centers of the enterprise.

An IP tunnel is established between the CPE and the LNS of each office center, when the PC1 under the enterprise branch 1 needs to communicate with the PC5 under the enterprise branch 2, the packet needs to pass through the CPE in the enterprise branch 1 first, and is encapsulated by the CPE into a tunnel packet to be transmitted to the LNS, the LNS decapsulates the tunnel packet and forwards the tunnel packet to the Intranet (i.e., Intranet) of the headquarters, and after the Intranet exchange finds that the packet needs to be forwarded to the PC5 of the enterprise branch 2, the packet is sent to the LNS, the LNS tunnel-encapsulates the packet, the opposite tunnel end is the CPE of the enterprise branch 2, and the CPE of the enterprise branch 2 receives the tunnel packet and decapsulates the tunnel packet and sends the tunnel packet to the corresponding PC 5.

It should be noted that the LNS is used as a tunnel server, and is configured to receive a tunnel packet from a mobile network side (i.e., each enterprise branch), decapsulate the tunnel packet and forward the decapsulated tunnel packet to a local area network of an enterprise headquarters, and receive a packet from the local area network of the enterprise headquarters, perform tunnel encapsulation, and forward the encapsulated packet to the other end (CPE) of the tunnel.

It can be seen that the centralized deployment method has the following disadvantages: (1) the load of the centralized LNS is heavy, all tunnel messages need to be processed, including encapsulation and decapsulation of the tunnel messages, wherein, the two-layer messages from the local area network of the headquarter of the enterprise are in a broadcast type, and the LNS encapsulates the messages into the tunnel messages and forwards the tunnel messages to the CPE of all enterprise branches; (2) failure of the centrally deployed LNS can result in disruption of all L2 network traffic; (3) the centralized forwarding has a large number of detours, which aggravates the network load and increases the network transmission delay.

Disclosure of Invention

In view of this, embodiments of the present invention provide a method, an apparatus, and a system for implementing a cross-domain two-layer network service, so as to improve network reliability and transmission efficiency, reduce network transmission delay, and thereby improve user experience.

In a first aspect, an embodiment of the present invention provides a method for implementing a cross-domain two-layer network service, where the method includes:

the method comprises the steps that a centralized controller obtains link state information of a plurality of tunnel servers, wherein the tunnel servers are distributed in a plurality of local area networks and used for establishing tunnels between any two local area networks, and each tunnel server is connected with a local gateway of the corresponding local area network;

the centralized controller determines transmission path information of a message to be transmitted according to link state information of the tunnel servers, wherein the message to be transmitted is a message transmitted from any one of the local area networks to other local area networks, and the transmission path information at least comprises: receiving address information of a tunnel server of a local area network of a message to be transmitted;

and the centralized controller sends the transmission path information of the message to be transmitted to the local gateway of the corresponding local area network, wherein the local gateway of the corresponding local area network sends the message to be transmitted to the tunnel server of the local area network receiving the message to be transmitted according to the transmission path information determined by the centralized controller.

In a second aspect, an embodiment of the present invention provides a system for implementing a cross-domain two-layer network service, including:

the tunnel servers are distributed in the local area networks and used for establishing tunnels between any two local area networks;

the local gateways are distributed in the local area networks and are connected with the tunnel servers of the corresponding local area networks;

the centralized controller is respectively connected with the local gateways and the tunnel servers and is used for acquiring link state information of the tunnel servers, determining transmission path information of a message to be transmitted according to the link state information of the tunnel servers and sending the transmission path information of the message to be transmitted to the local gateways of corresponding local area networks, wherein the message to be transmitted is a message transmitted from any one of the local area networks to other local area networks, and the transmission path information at least comprises: receiving address information of a tunnel server of a local area network of a message to be transmitted;

and the local gateway of the corresponding local area network sends the message to be transmitted to the tunnel server of the local area network receiving the message to be transmitted according to the transmission path information determined by the centralized controller.

In a second aspect, an embodiment of the present invention provides an apparatus for implementing a cross-domain two-layer network service, including:

the system comprises a link state information acquisition module, a link state information acquisition module and a link state information acquisition module, wherein the link state information acquisition module is used for acquiring link state information of a plurality of tunnel servers, the tunnel servers are distributed and deployed in a plurality of local area networks and are used for establishing tunnels between any two local area networks, and each tunnel server is connected with a local gateway of the corresponding local area network;

a transmission path determining module, configured to determine transmission path information of a to-be-transmitted message according to link state information of multiple tunnel servers, where the to-be-transmitted message is a message transmitted from any one of multiple local area networks to another local area network, and the transmission path information at least includes: receiving address information of a tunnel server of a local area network of a message to be transmitted;

a message transmission module, configured to send transmission path information of a message to be transmitted to a local gateway of a corresponding local area network, where the local gateway of the corresponding local area network sends the message to be transmitted to a tunnel server of the local area network that receives the message to be transmitted according to the determined transmission path information

In a third aspect, an embodiment of the present invention provides an electronic device, which includes a processor and a memory, where the memory is configured to store one or more computer instructions, and when the one or more computer instructions are executed by the processor, the method for implementing a cross-domain two-layer network service in the first aspect is implemented. The electronic device may also include a communication interface for communicating with other devices or a communication network.

An embodiment of the present invention provides a computer storage medium, configured to store a computer program, where the computer program, when executed, implements the implementation method of the cross-domain two-layer network service in the first aspect.

The method for implementing a cross-domain two-layer network service provided in the embodiments of the present invention employs a distributed deployment manner to deploy a plurality of tunnel servers and local gateways in a plurality of local area networks that need to implement cross-domain communication, and a centralized controller connected to the local gateway of each local area network detects link state information of the tunnel server of the corresponding local area network through the local gateway of each local area network, or is connected to the tunnel server of each local area network, directly obtains link state information of itself reported by the tunnel server of each local area network, and then determines transmission path information of a packet to be transmitted according to the obtained link state information of the tunnel server of each local area network. It is easy to note that the acquired link state information of each tunnel server includes, but is not limited to, location information, capacity information, operation state, delay information, link bandwidth, and load information of each tunnel server. When the transmission path is determined according to the link state information of each tunnel server, different parameter weights can be selected according to actual conditions to calculate and obtain the most suitable transmission path for transmitting the message to be transmitted.

When any local area network in a plurality of local area networks which need to be connected across domains needs to send a message to another local area network, a path request can be sent to the centralized controller to obtain a transmission path which is most suitable for transmitting the message, and then the message is transmitted by the most suitable transmission path.

Compared with the traditional centralized deployment mode of the tunnel servers, the distributed deployment mode of the tunnel servers can dynamically adjust the transmission path, and the risk that all network services are interrupted due to the failure of the centralized deployment tunnel servers is avoided. The centralized forwarding is not needed, detours are reduced, the network transmission delay is reduced, the network quality is greatly improved, and the user experience is enhanced.

It should be noted that the tunnel Server mentioned in this application may be an L2TP Network Server (L2TP Network Server, LNS); the local Gateway may be a Packet Data Gateway PGW (PDN Gateway) of an epc (evolved Packet core), or a collocated sgw (serving Gateway) and PGW, where the PGW is an egress Gateway of a mobile Network, and is close to an eNodeB side when being deployed in a distributed manner, or is collocated with the eNodeB, and may forward L3(layer 3, i.e., Network layer) Data packets of a client device (Customer Equipment, CPE) to the Internet, or forward L2(layer 2, i.e., Data link layer) tunnel packets to the LNS, where the local Gateway is close to a wireless side (eNodeB), and is referred to as lgw (local Gateway) hereinafter.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and those skilled in the art can also obtain other drawings according to the drawings without creative efforts.

Fig. 1 is a schematic diagram of a conventional L2 service implementation principle;

fig. 2 is a schematic diagram of a system for implementing a cross-domain two-layer network service according to an embodiment of the present invention;

fig. 3 is a flowchart of a method for implementing a cross-domain two-layer network service according to an embodiment of the present invention;

fig. 4 is a flowchart of an implementation method of an optional cross-domain two-layer network service according to an embodiment of the present invention;

fig. 5 is a flowchart of an implementation method of an optional cross-domain two-layer network service according to an embodiment of the present invention;

fig. 6 is a flowchart of an implementation method of an optional cross-domain two-layer network service according to an embodiment of the present invention;

fig. 7 is a schematic diagram of an implementation apparatus for a cross-domain two-layer network service according to an embodiment of the present invention;

fig. 8 is a schematic structural diagram of an electronic device corresponding to the implementation apparatus of the cross-domain two-layer network service provided in the embodiment shown in fig. 7.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, 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 terminology used in the embodiments of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in the examples of the present invention and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, and "a" and "an" generally include at least two, but do not exclude at least one, unless the context clearly dictates otherwise.

It should be understood that the term "and/or" as used herein is merely one type of association that describes an associated object, meaning that three relationships may exist, e.g., a and/or B may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

The words "if", as used herein, may be interpreted as "at … …" or "at … …" or "in response to a determination" or "in response to a detection", depending on the context. Similarly, the phrases "if determined" or "if detected (a stated condition or event)" may be interpreted as "when determined" or "in response to a determination" or "when detected (a stated condition or event)" or "in response to a detection (a stated condition or event)", depending on the context.

It is also noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a good or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such good or system. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a commodity or system that includes the element.

In addition, the sequence of steps in each method embodiment described below is only an example and is not strictly limited.

Before introducing the implementation method of the cross-domain two-layer network service provided by the embodiment of the present invention, some concepts related in subsequent embodiments and basic principles of implementation of the cross-domain two-layer network service are explained.

Tunneling is a way of transmitting data between networks by using the infrastructure of the internet. The data tunnelled may be data frames or data packets of different protocols. Tunneling is based on layer 2 or layer 3 tunneling protocols, respectively, wherein the layer 2tunneling protocol corresponds to the data link layer of the OSI model, using frames as data exchange units, PPTP (point-to-point tunneling protocol), L2TP (layer 2tunneling protocol), and L2F (layer 2 forwarding protocol) all belong to the layer 2tunneling protocol; the layer 3 tunneling protocol corresponds to a network layer of the OSI model, uses packets as data exchange units, and both of the ipip (ip over ip) and IPSec tunneling modes belong to the layer 3 tunneling protocol.

L2TP, collectively referred to as Layer 2Tunneling Protocol, is a data link Layer Protocol. The data is encapsulated using a PPP (Point to Point Protocol), and an additional header is added for transmission of the data over the internet.

LNS, which is called L2TP Network Server, i.e. L2TP Network Server, is a device on the PPP end system for processing the L2TP protocol Server end part, is located at one side of the L2TP tunnel, is a peer device of LAC (L2TP Access Concentrator ), and is a logical termination terminal of the PPP session tunneled by the LAC. And the LAC encapsulates the message received by the remote system into a tunnel message and then sends the tunnel message to the LNS, and the LNS decapsulates the received tunnel message and then sends the decapsulated tunnel message to the remote system.

The large two-layer network technology is a technology for realizing interconnection and intercommunication of two-layer networks by using a tunnel technology. The large two-layer network technology mentioned in the application refers to a two-layer network expansion technology which uses an IP network internet technology to realize spanning three-layer networks. For example, as shown in fig. 1, the CPE1 and the CPE2 passing through the enterprise branch 1 and the enterprise branch 2 respectively establish a tunnel with an LNS of an enterprise headquarters local area network (i.e., an intranet shown in fig. 1), the PC1 under the enterprise branch 1 encapsulates the packet into a tunnel packet, the tunnel packet is sent to the LNS through the tunnel between the CPE1 and the LNS, the LNS decapsulates the received tunnel packet, forwards the tunnel packet to the local area network of the enterprise headquarters, and encapsulates the tunnel packet through the LNS and sends the encapsulated packet to the CPE2 of the enterprise branch 2 when the packet is found to be sent to the PC5 under the enterprise branch 2, so that the CPE2 of the enterprise branch 2 sends the decapsulated packet to the PC 5.

In addition, in the centralized forwarding mode, a large number of detours exist in the transmission process, the network load is increased, and the bandwidth of a backbone network and the network transmission delay are increased.

In order to solve the above problems, in the present application, an SDWAN technology (Software-defined Wide Area Network) is applied to an L2 service scenario of a mobile Network, and a plurality of LNSs and local gateways LGWs deployed in a distributed manner in a plurality of local Area networks are adopted, so that automatic routing can be implemented, an optimal path is selected to transmit a packet, Network quality can be greatly improved, and user experience can be greatly enhanced.

Fig. 2 is a schematic diagram of a system for implementing a cross-domain two-layer network service according to an embodiment of the present invention, and as shown in fig. 2, the system may include: a plurality of tunnel servers (such as LNS1, LNS2 and LNS3 shown in fig. 1) distributed and deployed in a plurality of local area networks, and configured to establish a tunnel between any two local area networks; a plurality of local gateways (LGW 1, LGW2, LGW3, and LGW4 shown in fig. 1) distributed and deployed in a plurality of local area networks, connected to tunnel servers of the respective local area networks; the centralized controller is respectively connected with the local gateways and the tunnel server and is used for acquiring link state information of the LNSs, determining transmission path information of a message to be transmitted according to the link state information of the LNSs, and sending the transmission path information of the message to be transmitted to the LGW of the corresponding local area network, wherein the message to be transmitted is a message transmitted from any one of the local area networks to other local area networks, and the transmission path information at least comprises: receiving address information of a tunnel server of a local area network of a message to be transmitted; and the local gateway of the corresponding local area network sends the message to be transmitted to the tunnel server of the local area network receiving the message to be transmitted according to the transmission path information determined by the centralized controller.

It should be noted that, according to the service requirement of the enterprise L2, an LNS may be deployed at each enterprise branch, and each LNS is connected to the Intranet. Optionally, the LNS is co-located with the LGW. The LNSs share a virtual LNS IP for the Customer Premise Equipment (CPE) to establish an L2 tunnel.

And the centralized Controller is used for managing a global network topology and controlling each LGW, indicating that the LGW detects the path condition of each LNS in real time (including one or more of the following information, time delay to each LNS, load of each LNS and bandwidth to each LNS), calculating to obtain an optimal path from each LGW to each LNS after the information is collected by the Controller, informing each LGW of the optimal paths, and forwarding to a final LNS on the path according to a transmission path (for example, LGW1< - > LGW2< - > LGW4< - > LNS3) when the LGW receives a tunnel message of a virtual LNS IP, wherein the LNS forwards the tunnel message to an Intranet after the tunnel message is processed correctly.

In the application scenario, the present application provides an embodiment of a method for implementing a cross-domain two-layer network service, which may be applied to, but is not limited to, the system shown in fig. 2. Fig. 3 is a flowchart of a method for implementing a cross-domain two-layer network service according to an embodiment of the present invention, and as shown in fig. 3, the method includes the following steps:

step S301, the centralized controller obtains link state information of a plurality of tunnel servers, where the plurality of tunnel servers are deployed in a plurality of local area networks in a distributed manner, and are used to establish a tunnel between any two local area networks, and each tunnel server is connected to a local gateway of a corresponding local area network.

Specifically, the centralized controller is connected to a local gateway of each local area network, and the local gateway of each local area network is connected to a tunnel server of the local area network, so that as a first optional implementation manner, after the LGW of each local area network is deployed, the centralized controller may detect, by using the LGW of each local area network, link state information of an LNS of a corresponding local area network, so as to determine transmission path information of a packet to be transmitted according to the link state information of each LNS, where it needs to be noted that the link state information that needs to be obtained may include, but is not limited to, at least one of the following: position information, capacity information, running state, delay information, link bandwidth and load information of each tunnel server.

In a first optional implementation manner, when the centralized controller obtains the link state information of the LNS of the corresponding local area network through the LGW of each local area network, the centralized controller only needs to connect to the LGW of each local area network, and specifically, the step S301 may include the following steps: the method comprises the steps that a centralized controller sends a path detection request to a local gateway of each local area network, wherein the path detection request is used for indicating the local gateway of each local area network to detect link state information of a corresponding tunnel server, and the path detection request at least comprises network addresses of a plurality of tunnel servers to be detected; and the centralized controller receives the link state information of the tunnel server detected by the local gateway of each local area network according to the path detection request.

Optionally, the path detection request may further include a detection period, so as to achieve an objective that the LGW periodically and actively reports the link state information of the LNS of the corresponding local area network to the centralized controller. Specifically, the local gateway of each local area network sends a path detection request to the corresponding tunnel server according to a detection period so as to acquire link state information of the corresponding tunnel server; and periodically reporting the link state information of the corresponding tunnel server to the centralized controller.

It should be noted that, in the first embodiment, since the centralized controller is connected to only the LGW of each local area network, before the centralized controller obtains the link state information of the multiple tunnel servers, the centralized controller may further configure network topology information, and/or determine the network topology information according to the state information of the local gateway of each local area network, where the network topology information includes at least one of the following information of the local gateway of each local area network: location information, capacity information.

It is easy to note that since the LGW can only obtain the state information of the operation state, delay, link bandwidth, etc. of the LNS, some state information for calculating the transmission path (e.g., information of capacity, load, location, etc. of the LNS) may not be obtained. Therefore, as a second optional implementation manner, the centralized controller may also be directly connected to the LNS of each local area network, and directly acquire the status information of each LNS from the open interface of each LNS.

In a second optional implementation manner, the centralized controller is connected to the local gateway and the tunnel server of each local area network, respectively, so that the centralized controller receives the link state information of itself reported by the tunnel server of each local area network. Specifically, when the centralized controller receives the link state information of its own reported by the tunnel server of each local area network, the centralized controller may send a service request to the tunnel server of each local area network, and receive the link state information of its own returned by the tunnel server of each local area network according to the service request. The service request is used for indicating a tunnel server of each local area network to report the link state information of the service request;

optionally, the service request may include a reporting period, where the receiving, by the centralized controller, of the tunnel server in each local area network returns link state information of the centralized controller according to the service request includes: and the tunnel server of each local area network reports the self link state information to the centralized controller periodically according to the reporting period.

It should be noted that, in the second embodiment, the centralized controller is not only connected to the local gateway of each local area network, but also connected to the tunnel server of each local area network, so that before the centralized controller obtains the link state information of the plurality of tunnel servers, the centralized controller may further determine the network topology information according to the own state information actively reported by the local gateway of each local area network and the own state information reported by the tunnel server of each local area network, where the network topology information includes at least one of the following information of the local gateway and the tunnel server of each local area network: location information, capacity information.

Step S302, the centralized controller determines transmission path information of a message to be transmitted according to link state information of a plurality of tunnel servers, wherein the message to be transmitted is a message transmitted from any one of a plurality of local area networks to other local area networks, and the transmission path information at least comprises: and receiving the address information of the tunnel server of the local area network of the message to be transmitted.

Specifically, the centralized controller may automatically determine transmission path information of a packet to be transmitted after obtaining link state information of each tunnel server, or may determine transmission path information of a packet to be transmitted according to the obtained link state information of each tunnel server under the condition of a path request sent by a local gateway of each local area network, where the path request is a request sent to the centralized controller by the local gateway of each local area network when receiving a tunnel packet sent by client equipment of a corresponding local area network, and the tunnel packet is a tunnel packet generated by encapsulating the client equipment of the corresponding local area network with a virtual network address to be transmitted.

Step S303, the centralized controller sends the transmission path information of the to-be-transmitted message to the local gateway of the corresponding local area network, where the local gateway of the corresponding local area network sends the to-be-transmitted message to the tunnel server of the local area network that receives the to-be-transmitted message according to the transmission path information determined by the centralized controller.

Specifically, after the transmission path information of the packet to be transmitted is determined, that is, the real LNS IP address of the packet to be transmitted is determined, the destination address of the corresponding tunnel packet may be modified into the real LNS IP and forwarded to the LNS.

Optionally, the transmission path information determined by the centralized controller may be a path string, that is, it indicates that other LGWs need to be passed before the optimal LNS, and therefore, the transmission path information determined by the centralized controller may further include address information of one or more local gateways through which a message to be transmitted passes in the transmission process.

In an optional implementation manner, when the centralized controller sends the transmission path information of the packet to be transmitted to the local gateway of the corresponding local area network, the method may include the following steps: the centralized controller sends the transmission path information of the message to be transmitted to each local gateway through which the message to be transmitted passes in the transmission process; and based on the transmission path information of the message to be transmitted, each local gateway which the message to be transmitted passes through in the transmission process carries out secondary packaging on the received message by adopting the address of the local gateway or the tunnel server of the next transmission node, and transmits the message to the local gateway or the tunnel server of the next transmission node.

In another optional implementation manner, when the centralized controller sends the transmission path information of the packet to be transmitted to the local gateway of the corresponding local area network, the method may include the following steps: the centralized controller sends the transmission path information of the message to be transmitted to a first local gateway through which the message to be transmitted passes in the transmission process; and modifying the destination address of the message into the address of the local gateway or the tunnel server of the next transmission node based on the transmission path information of the message to be transmitted and each local gateway through which the message to be transmitted passes in the transmission process, and transmitting the address to the local gateway or the tunnel server of the next transmission node.

In the following, for better understanding of the present invention, fig. 4, fig. 5 and fig. 6 show alternative embodiments according to the implementation scheme of the cross-domain two-layer network service provided by the present application.

Fig. 4 shows a specific flow of a scheme for notifying establishment of an LNS tunnel by multiple APNs and EPC, as shown in fig. 4, including the following steps:

and step S400, topology reporting. After the LGWs are deployed, each LGW actively sends a message to the centralized controller to inform the centralized controller of its own state information, which may include one or more of the following: functional characteristics, traffic capacity, location information. Step S400 is optional.

Step S401, topology management. That is, at the initial time of the system, the centralized controller configures the network topology, or implements automatic topology discovery through step S400.

Step S402, the centralized controller sends a path probe request to each LGW. The path detection request may be used to indicate that the LGW periodically detects a path state of each LNS, and optionally, the path detection request may carry multiple LNS IPs to be detected, and optionally, may also carry information such as a detection period duration.

In step S403, path detection is performed. After receiving a path detection request from the centralized controller, the LGW of each local area network regularly sends the path detection request to the LNS according to a detection period, and obtains link state information of the LNS, where the obtained information includes one or more of the following information: whether the LNS is operating normally, time delay, link bandwidth, LNS capacity, and LNS location.

Step S404, the LGW of each local area network reports the detection result of the detection path to the centralized controller. The reporting mode may be periodic reporting, or real-time reporting based on a path detection request of the centralized controller.

In step S405, the centralized controller returns the determined transmission path information to each LGW. Wherein each LGW may be actively pushed through step S405 a. It is also possible to return transmission path information to each LGW in the case of receiving a path request through step S405b1 and step S405b 2. Specifically, after receiving an L2 tunnel message sent by the CPE to the virtual LNS IP, the LGW of each local area network sends a path request to the centralized controller, and the centralized controller obtains the LNS of the optimal path through calculation and returns the real IP of the selected LNS to the LGW. Specifically, the path detection result information reported by the LGW before the calculation is considered, that is, the information such as the running state, delay, capacity, bandwidth, and location of the LNS is considered.

It is easy to note that the two manners may be optional, where in step S405, after obtaining the reported path detection result of the LGW, the centralized controller calculates the currently most suitable LNS for each LGW and actively informs the calculated LNS to each LGW; and step S405b1 and step S405b2 are passive, and when the LGW receives the request, the most suitable LNS is selected to notify the LGW.

And finally, after the LGW obtains the selected real LNS IP, modifying the tunnel message purpose into the real LNS IP and forwarding the real LNS IP to the LNS.

It should be noted that in the embodiment shown in fig. 4, the centralized controller only controls the LGW, and in the embodiment shown in fig. 5, the centralized controller can control both the LGW and the LNS. And the LNS open interface of each local area network is sent to the centralized controller, and the related information is directly reported to the centralized controller. Specifically, the method comprises the following steps:

and step S500, topology reporting. After the LGW and the LNS are deployed, the LGW actively connects to the centralized controller to report its own status information through step S500a, and the LNS actively connects to the centralized controller to report its own status information through step S500b, where the reported information includes one or more of the following: capability information (LGW versus LNS), capacity information, location information.

Step S501, the centralized controller manages information reported by the LGW and the LNS, and generates a logical topology network map for management.

Step S502, the centralized controller sends a path probe request to each LGW. The path detection request may be used to indicate that the LGW periodically detects the path status of each LNS, may be sent periodically by the centralized controller, and may also inform the LGW for one period to allow the LGW to periodically detect.

In step S503, a path is detected. The LGW of each local area network sends a detection message to the LNS so as to obtain the state and time delay information of the LNS. Alternatively, probing may be initiated periodically on an active basis.

In step S504, the LGW periodically transmits the path detection result to the centralized controller. The information in the probing results includes, but is not limited to, one or more of status, latency, and bandwidth of the respective LNSs.

Step S505 and S506, similar to step S502, the centralized controller may periodically send a service request to each LNS to query information such as service status, load, and the like of each LNS; the LNS may also be instructed to report these information periodically on its own initiative.

Step S507 is the same as step S405 shown in fig. 4. The transmission path information that the centralized controller can determine is actively pushed to each LGW through step S507 a. It is also possible to return transmission path information to each LGW in the case of receiving a path request through step S507b1 and step S507b 2. After receiving an L2 tunnel message sent to the virtual LNS IP by a CPE, an LGW of each local area network sends a path request to the centralized controller, the centralized controller selects an optimal LNS by calculating the optimal path, and returns the real IP of the selected LNS to the LGW. Specifically, the path detection result information reported by the LGW before the calculation may be considered, that is, the information such as the operating state, delay, capacity, bandwidth, and location of the LNS may be considered.

It is easy to note that the two manners may be optional, where in step S507a, after the central controller obtains the reported path detection result of the LGWs, it calculates the currently most suitable LNS for each LGW and actively informs each LGW of the calculated currently most suitable LNS; steps S507b1 and S507b2 are passive, and when a request from the LGW is received, the most suitable LNS is selected and notified to the LGW.

In the same embodiment as the first embodiment, after obtaining the selected true LNS IP, the LGW modifies the tunnel packet destination to the true LNS IP and forwards the modified true LNS IP to the LNS.

Fig. 6 shows an embodiment, which is similar to fig. 4 and 5, and is different from that a path string is calculated by the centralized controller, and indicates that another LGW needs to be passed before the optimal LNS, where the specific flow includes the following steps:

the content executed by the steps S600a, S600b, S601, S602, S603, S604, S605, S606 is the same as that described in steps S500a, S500b, S501, S502, S503, S504, S505, S506 shown in fig. 5.

Step S607, after receiving the path request, the centralized controller obtains a path string to the final LNS according to an algorithm. Taking the path string LGW1< - > LGW3< - > LNS3 shown in fig. 2 as an example, there can be two processing manners:

first, the centralized controller informs each LGW packet processing rule on the path, as in the above figures, LGW1 and LGW3 need to be informed. The LGW1 encapsulates the tunnel packet again by one layer and forwards the tunnel packet to LGW3, and then LGW3 decapsulates the tunnel packet according to the rule indicated by the centralized controller and forwards the tunnel packet to LNS3, that is, the destination IP of the modified tunnel packet is the actual IP of LNS 3.

Secondly, the centralized controller only informs the LGW1 of the path string and the processing rule, that is, the step of step S607b2 shown in fig. 6 is optional, when the LGW1 receives a packet, the destination address of the tunnel packet is modified to be the address of the LGW3 and the path string is carried in each tunnel packet, and after the LGW on the path receives the packet, the modified destination address of the path string is obtained as the next hop in the path string. And so ultimately to LNS 3.

Fig. 7 is a schematic structural diagram of an apparatus for implementing a cross-domain two-layer network service according to an embodiment of the present invention, as shown in fig. 7, the apparatus includes: a link state information obtaining module 11, a transmission path determining module 12, and a message transmission module 13.

A link status information obtaining module 11, configured to obtain link status information of multiple tunnel servers, where the multiple tunnel servers are deployed in multiple local area networks in a distributed manner, and are used to establish a tunnel between any two local area networks, and each tunnel server is connected to a local gateway of a corresponding local area network;

a transmission path determining module 12, configured to determine transmission path information of a to-be-transmitted message according to link state information of multiple tunnel servers, where the to-be-transmitted message is a message transmitted from any one of multiple local area networks to another local area network, and the transmission path information at least includes: receiving address information of a tunnel server of a local area network of a message to be transmitted;

and the message transmission module 13 is configured to send transmission path information of the message to be transmitted to a local gateway of a corresponding local area network, where the local gateway of the corresponding local area network sends the message to be transmitted to a tunnel server of the local area network that receives the message to be transmitted according to the determined transmission path information.

Optionally, the link state information obtaining module 11 is further configured to send a path detection request to a local gateway of each local area network, where the path detection request is used to instruct the local gateway of each local area network to detect link state information of a corresponding tunnel server, where the path detection request at least includes network addresses of a plurality of tunnel servers to be detected; receiving link state information of the tunnel server detected by the local gateway of each local area network according to the path detection request, wherein the link state information comprises at least one of the following: position information, capacity information, running state, delay information, link bandwidth and load information of each tunnel server.

Optionally, the path detection request further includes a detection period, and the local gateway of each local area network sends the path detection request to the corresponding tunnel server according to the detection period, so as to obtain link state information of the corresponding tunnel server; and the local gateway of each local area network reports the link state information of the corresponding tunnel server to the centralized controller periodically.

Optionally, the apparatus may further include: the network topology determining module is configured to configure network topology information and/or determine the network topology information according to state information of the local gateway of each local area network, where the network topology information includes at least one of the following information of the local gateway of each local area network: location information, capacity information.

Optionally, the link status information obtaining module 11 is further configured to receive link status information of itself reported by a tunnel server of each local area network.

Optionally, the link state information obtaining module 11 is further configured to send a service request to a tunnel server of each local area network, where the service request is used to instruct the tunnel server of each local area network to report link state information of itself; and receiving the link state information returned by the tunnel server of each local area network according to the service request.

Optionally, the service request includes a reporting period, and the tunnel server of each local area network periodically reports its own link state information to the centralized controller according to the reporting period.

Optionally, the network topology determining module is further configured to determine, by the centralized controller, network topology information according to the state information of the local gateway of each local area network that is actively reported by the local gateway of each local area network and the state information of the tunnel server of each local area network, where the network topology information includes at least one of the following information of the local gateway of each local area network and the tunnel server: location information, capacity information.

Optionally, the message transmission module 13 is further configured to determine transmission path information of a message to be transmitted according to link state information of multiple tunnel servers when receiving a path request sent by each local gateway, where the path request is a request sent to the centralized controller by each local gateway of the local area network when receiving a tunnel message sent by a client device of the corresponding local area network, and the tunnel message is a tunnel message generated by encapsulating, by the client device of the corresponding local area network, the message to be transmitted by using a virtual network address.

Optionally, the transmission path information includes address information of one or more local gateways through which the to-be-transmitted message passes in the transmission process, and the message transmission module 13 is further configured to send, by the centralized controller, the transmission path information of the to-be-transmitted message to each local gateway through which the to-be-transmitted message passes in the transmission process; and based on the transmission path information of the message to be transmitted, each local gateway which the message to be transmitted passes through in the transmission process carries out secondary packaging on the received message by adopting the address of the local gateway or the tunnel server of the next transmission node, and transmits the message to the local gateway or the tunnel server of the next transmission node.

Optionally, the message transmission module 13 is further configured to send transmission path information of the message to be transmitted to a first local gateway through which the message to be transmitted passes in a transmission process; and modifying the destination address of the message into the address of the local gateway or the tunnel server of the next transmission node based on the transmission path information of the message to be transmitted and each local gateway through which the message to be transmitted passes in the transmission process, and transmitting the address to the local gateway or the tunnel server of the next transmission node.

The apparatus shown in fig. 7 can perform the method of the embodiment shown in fig. 3-6, and the detailed description of this embodiment can refer to the related description of the embodiment shown in fig. 3-6. The implementation process and technical effect of the technical solution refer to the descriptions in the embodiments shown in fig. 3 to fig. 6, and are not described herein again.

While the internal functions and structures of the implementation apparatus for cross-domain two-layer network services are described above, in one possible design, the structure of the implementation apparatus for cross-domain two-layer network services may be implemented as an electronic device, for example, a server device for managing network services, as shown in fig. 8, the electronic device may include: a processor 21 and a memory 22. Wherein the memory 22 is used for storing a program that supports an electronic device to execute the implementation method of the cross-domain two-layer network service provided in the embodiments shown in fig. 3 to fig. 6, and the processor 21 is configured to execute the program stored in the memory 22.

The program comprises one or more computer instructions which, when executed by the processor 21, are capable of performing the steps of:

acquiring link state information of a plurality of tunnel servers, wherein the tunnel servers are distributed in a plurality of local area networks and used for establishing tunnels between any two local area networks, and each tunnel server is connected with a local gateway of the corresponding local area network;

determining transmission path information of a message to be transmitted according to link state information of a plurality of tunnel servers, wherein the message to be transmitted is a message transmitted from any one of a plurality of local area networks to other local area networks, and the transmission path information at least comprises: receiving address information of a tunnel server of a local area network of a message to be transmitted;

and transmitting the transmission path information of the message to be transmitted to the local gateway of the corresponding local area network, wherein the local gateway of the corresponding local area network transmits the message to be transmitted to the tunnel server of the local area network receiving the message to be transmitted according to the determined transmission path information.

Optionally, the processor 21 is further configured to perform all or part of the steps in the embodiments shown in fig. 3 to 6.

The electronic device may further include a communication interface 23 for communicating with other devices or a communication network.

In addition, the embodiment of the present invention provides a computer storage medium for storing computer software instructions for an electronic device, which includes a program for executing the method for implementing the cross-domain two-layer network service in the method embodiments shown in fig. 3 to fig. 6.

The above-described embodiments of the apparatus are merely illustrative, and the units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.

Through the above description of the embodiments, those skilled in the art will clearly understand that each embodiment can be implemented by adding a necessary general hardware platform, and of course, can also be implemented by a combination of hardware and software. With this understanding in mind, the above-described aspects and portions of the present technology which contribute substantially or in part to the prior art may be embodied in the form of a computer program product, which may be embodied on one or more computer-usable storage media having computer-usable program code embodied therein, including without limitation disk storage, CD-ROM, optical storage, and the like.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable cross-domain, two-layer network service implementing device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable cross-domain, two-layer network service implementing device, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable cross-domain two-layer network service implementing device to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

In a typical configuration, a computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

The memory may include forms of volatile memory in a computer readable medium, Random Access Memory (RAM) and/or non-volatile memory, such as Read Only Memory (ROM) or flash memory (flash RAM). Memory is an example of a computer-readable medium.

Computer-readable media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), Read Only Memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, compact disc read only memory (CD-ROM), Digital Versatile Discs (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information that can be accessed by a computing device. As defined herein, a computer readable medium does not include a transitory computer readable medium such as a modulated data signal and a carrier wave.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

The application discloses A1, a method for realizing cross-domain two-layer network service, including:

the centralized controller determines transmission path information of a message to be transmitted according to the link state information of the tunnel servers, wherein the message to be transmitted is a message transmitted from any one of the local area networks to other local area networks, and the transmission path information at least includes: receiving address information of a tunnel server of the local area network of the message to be transmitted;

and the centralized controller sends the transmission path information of the message to be transmitted to a local gateway of a corresponding local area network, wherein the local gateway of the corresponding local area network sends the message to be transmitted to a tunnel server of the local area network receiving the message to be transmitted according to the transmission path information determined by the centralized controller.

A2, according to the method described in a1, the centralized controller is connected to the local gateway of each lan, wherein the acquiring, by the centralized controller, link state information of a plurality of tunnel servers includes:

the centralized controller sends a path detection request to a local gateway of each local area network, where the path detection request is used to instruct the local gateway of each local area network to detect link state information of a corresponding tunnel server, where the path detection request at least includes network addresses of a plurality of tunnel servers to be detected;

the centralized controller receives link state information of the tunnel server detected by the local gateway of each local area network according to the path detection request, wherein the link state information includes at least one of the following: position information, capacity information, running state, delay information, link bandwidth and load information of each tunnel server.

A3, according to the method in a2, the path probing request further includes a probing period, where the receiving, by the centralized controller, link state information of a tunnel server that is probed by a local gateway of each local area network according to the path probing request includes:

the local gateway of each local area network sends a path detection request to the corresponding tunnel server according to the detection period so as to acquire the link state information of the corresponding tunnel server;

and the local gateway of each local area network reports the link state information of the corresponding tunnel server to the centralized controller periodically.

A4, before the centralized controller acquires the link state information of the plurality of tunnel servers according to the method of A2, the method further includes:

the centralized controller configures network topology information, and/or determines the network topology information according to self state information actively reported by the local gateway of each local area network, wherein the network topology information includes at least one of the following information of the local gateway of each local area network: location information, capacity information.

A5, according to the method described in a1, the centralized controller is connected to the local gateway and the tunnel server of each lan, respectively, wherein the acquiring, by the centralized controller, link state information of a plurality of tunnel servers includes:

and the centralized controller receives the self link state information reported by the tunnel server of each local area network.

A6, according to the method in a5, the receiving, by the centralized controller, link state information of the centralized controller, which is reported by the tunnel server of each local area network, includes:

the centralized controller sends a service request to the tunnel server of each local area network, wherein the service request is used for indicating the tunnel server of each local area network to report the link state information of the tunnel server;

and the centralized controller receives the link state information returned by the tunnel server of each local area network according to the service request.

A7, according to the method described in a6, the service request includes a reporting period, where the receiving, by the centralized controller, of the link state information of each tunnel server of each local area network according to the service request includes:

and the tunnel server of each local area network reports the link state information of the tunnel server to the centralized controller periodically according to the reporting period.

A8, before the centralized controller acquires the link state information of the plurality of tunnel servers according to the method of A5, the method further includes:

the centralized controller determines network topology information according to the self state information actively reported by the local gateway of each local area network and the self state information reported by the tunnel server of each local area network, wherein the network topology information includes at least one of the following information of the local gateway and the tunnel server of each local area network: location information, capacity information.

A9, according to the method described in any one of a1 to A8, where the determining, by the centralized controller, transmission path information of a packet to be transmitted according to the link state information of the plurality of tunnel servers includes:

and the centralized controller determines transmission path information of a message to be transmitted according to link state information of the tunnel servers under the condition that a path request sent by each local gateway is received, wherein the path request is a request sent to the centralized controller by each local gateway of the local area network under the condition that the local gateway of the local area network receives a tunnel message sent by client equipment of the corresponding local area network, and the tunnel message is a tunnel message generated by the client equipment of the corresponding local area network by encapsulating the message to be transmitted by adopting a virtual network address.

A10, according to the method described in a9, the transmission path information includes address information of one or more local gateways through which the packet to be transmitted passes in the transmission process, where the sending, by the centralized controller, the transmission path information of the packet to be transmitted to the local gateways of the corresponding local area networks includes:

the centralized controller sends the transmission path information of the message to be transmitted to each local gateway through which the message to be transmitted passes in the transmission process;

and based on the transmission path information of the message to be transmitted, each local gateway which the message to be transmitted passes through in the transmission process carries out secondary packaging on the received message by adopting the address of the local gateway or the tunnel server of the next transmission node, and transmits the message to the local gateway or the tunnel server of the next transmission node.

A11, according to the method described in a9, the transmission path information includes address information of one or more local gateways through which the packet to be transmitted passes in the transmission process, where the sending, by the centralized controller, the transmission path information of the packet to be transmitted to the local gateways of the corresponding local area networks includes:

the centralized controller sends the transmission path information of the message to be transmitted to a first local gateway through which the message to be transmitted passes in the transmission process;

and modifying the destination address of the message into the address of the local gateway or the tunnel server of the next transmission node based on the transmission path information of the message to be transmitted and each local gateway through which the message to be transmitted passes in the transmission process, and transmitting the address to the local gateway or the tunnel server of the next transmission node.

The application discloses B12, a realization system of cross-domain two-layer network service, includes:

the centralized controller is respectively connected with the local gateways and the tunnel servers, and is configured to acquire link state information of the tunnel servers, determine transmission path information of a to-be-transmitted message according to the link state information of the tunnel servers, and send the transmission path information of the to-be-transmitted message to the local gateways of corresponding local area networks, where the to-be-transmitted message is a message transmitted from any one of the local area networks to other local area networks, and the transmission path information at least includes: receiving address information of a tunnel server of the local area network of the message to be transmitted;

and the local gateway of the corresponding local area network sends the message to be transmitted to a tunnel server of the local area network receiving the message to be transmitted according to the transmission path information determined by the centralized controller.

The application discloses C13, a realization device of cross-domain two-layer network service includes:

a transmission path determining module, configured to determine transmission path information of a to-be-transmitted packet according to link state information of the tunnel servers, where the to-be-transmitted packet is a packet transmitted from any one of the local area networks to another local area network, and the transmission path information at least includes: receiving address information of a tunnel server of the local area network of the message to be transmitted;

and the message transmission module is used for transmitting the transmission path information of the message to be transmitted to a local gateway of a corresponding local area network, wherein the local gateway of the corresponding local area network transmits the message to be transmitted to a tunnel server of the local area network for receiving the message to be transmitted according to the determined transmission path information.

The application discloses D14, an electronic equipment includes: a memory, a processor; wherein the content of the first and second substances,

the memory is configured to store one or more computer instructions that, when executed by the processor, implement a method of implementing a cross-domain two-layer network service as recited in any one of a 1-a 11.

Claims

1. A method for realizing cross-domain two-layer network service is characterized by comprising the following steps:

the method comprises the steps that a centralized controller obtains link state information of a plurality of tunnel servers, wherein the tunnel servers are distributed in a plurality of local area networks and used for establishing tunnels between any two local area networks, and each tunnel server is connected with a local gateway of the corresponding local area network; wherein the tunnel server comprises an LNS;

the centralized controller determines transmission path information of a message to be transmitted according to the link state information of the tunnel servers, wherein the message to be transmitted is a message transmitted from any one of the local area networks to other local area networks, and the transmission path information at least includes: receiving address information of a tunnel server of the local area network of the message to be transmitted; the message to be transmitted comprises an L2 layer message;

and the centralized controller sends the transmission path information of the message to be transmitted to a local gateway of a corresponding local area network, wherein the local gateway of the corresponding local area network sends the L2 tunnel message to a tunnel server of the local area network receiving the L2 tunnel message according to the transmission path information determined by the centralized controller.

2. The method of claim 1, wherein a centralized controller is connected to the local gateway of each lan, and wherein the acquiring, by the centralized controller, the link state information of the plurality of tunnel servers comprises:

3. The method according to claim 2, wherein the path probing request further includes a probing period, and wherein the receiving, by the centralized controller, link state information of the tunnel server that is detected by the local gateway of each local area network according to the path probing request includes:

4. The method of claim 2, wherein before the centralized controller obtains the link state information of the plurality of tunnel servers, the method further comprises:

5. The method of claim 1, wherein the centralized controller is connected to the local gateway and the tunnel server of each local area network, respectively, and wherein the acquiring, by the centralized controller, the link state information of the plurality of tunnel servers comprises:

6. The method according to claim 5, wherein the receiving, by the centralized controller, the own link state information reported by the tunnel server of each local area network includes:

7. The method of claim 6, wherein the service request includes a reporting period, and wherein the receiving, by the centralized controller, the link state information of the tunnel server of each local area network that returns to the centralized controller according to the service request includes:

8. The method of claim 5, wherein before the centralized controller obtains the link state information of the plurality of tunnel servers, the method further comprises:

9. The method according to any one of claims 1 to 8, wherein the determining, by the centralized controller, transmission path information of the packet to be transmitted according to the link state information of the plurality of tunnel servers includes:

10. The method according to claim 9, wherein the transmission path information includes address information of one or more local gateways through which the packet to be transmitted passes in a transmission process, and wherein the sending, by the centralized controller, the transmission path information of the packet to be transmitted to the local gateways of the corresponding local area networks includes:

11. The method according to claim 9, wherein the transmission path information includes address information of one or more local gateways through which the packet to be transmitted passes in a transmission process, and wherein the sending, by the centralized controller, the transmission path information of the packet to be transmitted to the local gateways of the corresponding local area networks includes:

12. A system for implementing cross-domain two-layer network service is characterized by comprising:

the tunnel servers are distributed in the local area networks and used for establishing tunnels between any two local area networks; wherein the tunnel server comprises an LNS;

the centralized controller is respectively connected with the local gateways and the tunnel servers, and is configured to acquire link state information of the tunnel servers, determine transmission path information of a to-be-transmitted message according to the link state information of the tunnel servers, and send the transmission path information of the to-be-transmitted message to the local gateways of corresponding local area networks, where the to-be-transmitted message is a message transmitted from any one of the local area networks to other local area networks, and the transmission path information at least includes: receiving address information of a tunnel server of the local area network of the message to be transmitted; the message to be transmitted comprises an L2 layer message;

and the local gateway of the corresponding local area network sends the L2 tunnel message to the tunnel server of the local area network receiving the L2 tunnel message according to the transmission path information determined by the centralized controller.

13. An apparatus for implementing a cross-domain two-layer network service, comprising:

the system comprises a link state information acquisition module, a link state information acquisition module and a link state information acquisition module, wherein the link state information acquisition module is used for acquiring link state information of a plurality of tunnel servers, the tunnel servers are distributed and deployed in a plurality of local area networks and are used for establishing tunnels between any two local area networks, and each tunnel server is connected with a local gateway of the corresponding local area network; wherein the tunnel server comprises an LNS;

a transmission path determining module, configured to determine transmission path information of a to-be-transmitted packet according to link state information of the tunnel servers, where the to-be-transmitted packet is a packet transmitted from any one of the local area networks to another local area network, and the transmission path information at least includes: receiving address information of a tunnel server of the local area network of the message to be transmitted; the message to be transmitted comprises an L2 layer message;

and the message transmission module is used for sending the transmission path information of the message to be transmitted to a local gateway of a corresponding local area network, wherein the local gateway of the corresponding local area network sends the L2 tunnel message to a tunnel server of the local area network receiving the L2 tunnel message according to the determined transmission path information.

14. An electronic device, comprising: a memory, a processor; wherein the content of the first and second substances,

the memory is configured to store one or more computer instructions that, when executed by the processor, implement the method of implementing a cross-domain two-layer network service of any of claims 1-11.