CN110875880B

CN110875880B - Data transmission method, related equipment, system and computer storage medium

Info

Publication number: CN110875880B
Application number: CN201810998866.4A
Authority: CN
Inventors: 孙春霞; 张耀坤
Original assignee: Beijing Huawei Digital Technologies Co Ltd
Current assignee: Beijing Huawei Digital Technologies Co Ltd
Priority date: 2018-08-29
Filing date: 2018-08-29
Publication date: 2022-03-25
Anticipated expiration: 2038-08-29
Also published as: CN110875880A

Abstract

The application discloses a data transmission method, related equipment, a system and a computer storage medium, relates to the technical field of communication, and can prevent E-Trunk from mistakenly switching double masters, avoid the problem that CE receives double data due to the double masters, and improve the reliability of data transmission in equipment link aggregation. Wherein, the method comprises the following steps: the first PE equipment determines that the first single board fails, whether the first single board is the single board where the BFD state machine is located is judged, if yes, whether the first PE equipment contains the second single board which does not fail is judged, if yes, the first PE equipment sends a BFD message to the second PE equipment through the second single board, and the BFD message is used for indicating that the second PE equipment does not carry out backup upgrading. And the second PE equipment receives the BFD message sent by the first PE equipment by adopting the second single board without performing backup upgrading.

Description

Data transmission method, related equipment, system and computer storage medium

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a data transmission method, a related device, a system, and a computer storage medium.

Background

With the wide application of Ethernet technology in the field of metropolitan area networks and wide area networks, operators have made higher and higher requirements on bandwidth and reliability of backbone links using Ethernet (Ethernet) technology. In conventional techniques, it is common to replace high-rate interface boards, or devices that support high-rate interface boards, to increase bandwidth. However, such solutions require a high outlay and are not flexible enough. The link aggregation technology can achieve the purpose of increasing the link bandwidth by binding a plurality of physical interfaces into one logical interface without replacing equipment. If the link aggregation adopts a mechanism of backup links, the reliability of the links between the devices can be effectively improved.

The link aggregation technology can aggregate a plurality of physical ports into a port aggregation (Trunk) port to increase the bandwidth, and can also detect limited faults such as disconnection of member links in the same Trunk. But the common link aggregation technology cannot detect the failures such as link layer failure, link misconnection and the like. After the technology of Link Aggregation Control Protocol (LACP) appears, the fault tolerance of Trunk is improved, and the high reliability of the member links in Trunk is ensured.

An Enhanced link aggregation (E-Trunk) control protocol is expanded based on LACP, and link aggregation among multiple devices can be realized, so that link reliability is improved from a single-board level to a device level. The E-Trunk control protocol is mainly applied to link protection between a Provider Edge (PE) device and a PE device and protection of node failure of the PE device when a Customer Edge (CE) device is dually accessed to a virtual private local area network service (VPLS), a Virtual Leased Line (VLL), an edge-to-edge pseudowire emulation (PWE 3) network. Before E-Trunk is not used, a CE device can only be connected to one PE over a single one of Ethernet aggregation (Eth-Trunk) links. If the Eth-Trunk fails or the PE fails, the CE will not be able to continue communicating with the PE. After using the E-Trunk, the CE may be dually homed to two PEs, where one PE serves as a primary device and the other PE serves as a secondary device, thereby implementing inter-device protection.

Two PE devices that a CE device has dual homing access will generate two primary devices simultaneously used to receive data when negotiation is unsuccessful. For example, to ensure fast switching of the E-Trunk, Bidirectional Forwarding Detection (BFD) is deployed for the primary device and the standby device, and the BFD detects a Trunk interface or a Trunk member port on the primary device, and the standby device can quickly sense through the BFD when a link failure from the primary device to the CE occurs. After the BFD session is established, the BFD message can be periodically and quickly sent, if the BFD message is not received in the detection time, the bidirectional forwarding path is considered to have a fault, and E-Trunk switching can be triggered.

When there is more than one Trunk member port on each PE and there are multiple single boards on the main device, the Trunk member ports may be located on different single boards, and when performing BFD detection on the PE, a BFD state machine needs to be operated, and the BFD detection implements various processing functions based on the state machine, and the BFD state machine also needs to be located on one single board. There are thus situations where: the single board where the Trunk member interface for receiving and sending the BFD message is located is not the same as the single board running the BFD state machine. When the BFD state machine single board on the main equipment fails and the standby equipment cannot receive the BFD message, the fault of PE1 is judged, and the E-Trunk processing module on PE2 is linked to operate the E-Trunk master. But actually, at this time, besides the failed board, other E-Trunk interfaces on other boards that have not failed may be used to continue to receive and send BFD messages if the E-Trunk interfaces survive, and there is no Trunk Down (session tear Down). Under the condition, after the PE2E-Trunk is upgraded, the multicast message is immediately forwarded to the CE, and the CE sends the multicast message to the terminal, so that the terminal receives two multicast streams of PE1 and PE2, which causes video screen splash.

Disclosure of Invention

Embodiments of the present invention provide a data transmission method, a related device, a system, and a computer storage medium, which can prevent an E-Trunk from mistakenly switching two masters, avoid a problem that a CE receives duplicate data due to the two masters, and improve reliability of data transmission in device link aggregation.

In a first aspect, an embodiment of the present invention provides a data transmission method, which is applied to a first PE device side, and the method includes: if the first single board of the first PE device fails, the first PE device determines whether the first single board is the single board where the BFD state machine is located. If the first single board is the single board where the BFD state machine is located, and the first PE device includes a second single board which does not have a fault, the first PE device sends a BFD message to the second PE device by using the second single board, wherein the BFD message is used for indicating that the second PE device does not perform backup upgrading.

If the single board with the failure of the first PE device is a single board on which the BFD state machine operates and the first PE device further includes other second single boards without failures, the first PE device may switch the BFD state machine to the second single board and send a BFD packet to the second PE device by using the second single board, thereby notifying the second PE device not to perform a backup up main process, thereby avoiding a problem of dual main devices due to the fact that the second PE device mistakenly assumes that the first PE device has a failure to perform backup up main, avoiding a problem of receiving duplicate data by the CE, and improving reliability of data transmission in device link aggregation.

In one possible design, the method further includes: if the first board is the board where the BFD state machine is located, and the first PE device includes the second board that has not failed, the first PE device forwards the received service data to the CE device.

By implementing the embodiment of the present invention, if the first PE device includes a second single board that has not failed in addition to the failed single board, the first PE device forwards data to the CE device by using the second single board that has not failed, so that the communication link with the CE device can be quickly recovered, and the reliability of data transmission in the device link aggregation is improved.

In a second aspect, an embodiment of the present invention provides a data transmission method, which is applied to a second PE device side, and the method includes: and the second PE equipment determines that the first PE equipment has single-board failure. And the second PE equipment receives the BFD message sent by the first PE equipment by adopting the single board without the fault. And if the second PE equipment carries out backup upgrading, the second PE equipment is switched back to the backup equipment by the main equipment according to the BFD message. And if the second PE equipment does not carry out backup upgrading, the second PE equipment determines that the second PE equipment is the backup equipment according to the BFD message.

When the method described in the second aspect is implemented, after the second PE device learns that the first board of the first PE device fails, the standby main process is executed, and if the first PE device further includes other second boards that do not fail, the second PE device receives a BFD message sent by the first PE device by using the boards that do not fail, and the second PE device learns that the boards that do not fail still exist in the first PE device according to the BFD message, and returns the second PE device to the standby device, thereby avoiding a problem of dual main devices caused by the fact that the second PE device mistakenly performs the standby main for the failure of the first PE device, avoiding a problem that the CE receives dual data, and improving reliability of data transmission in device link aggregation.

In one possible design, the switching, by the second PE device, from the master device to the standby device according to the BFD packet includes: the second PE device stops forwarding the received service data to the CE device.

By implementing the embodiment of the invention, the problem of double main equipment caused by the fact that the second PE equipment mistakenly takes the first PE equipment fault as the backup master can be avoided, the problem that the CE receives double data is avoided, and the reliability of data transmission in equipment link aggregation is improved.

In a third aspect, an embodiment of the present invention provides a PE device, where the PE device is a first PE device, and the first PE device includes a module or a unit configured to execute the data transmission method described in the first aspect.

In a fourth aspect, an embodiment of the present invention provides a PE device, where the PE device is a second PE device, and the second PE device includes a module or a unit configured to execute the data transmission method described in the second aspect.

In a fifth aspect, an embodiment of the present invention provides another PE device, where the PE device is a first PE device, and the first PE device includes a processor, a transceiver, and a memory. The processor is configured to call the data transmission program code stored in the memory to execute the data transmission method provided in the first aspect.

In a sixth aspect, an embodiment of the present invention provides another PE device, where the PE device is a second PE device, and the second PE device includes a processor, a transceiver, and a memory. The processor is used for calling the data transmission program code stored in the memory to execute the data transmission method provided by the second aspect.

In a seventh aspect, an embodiment of the present invention provides a communication system, including: a first PE device, a second PE device, and a CE device. Wherein: the first PE device is the first PE device in the third aspect or the fifth aspect, and the second PE device is the second PE device in the fourth aspect or the sixth aspect.

In an eighth aspect, an embodiment of the present invention provides a computer storage medium for storing computer software program instructions for a first PE device according to the first aspect, where the program instructions, when executed by the first PE device, cause the first PE device to perform the method according to the first aspect.

In a ninth aspect, an embodiment of the present invention provides a computer storage medium for storing computer software program instructions for a second PE device according to the second aspect, where the program instructions, when executed by the second PE device, cause the second PE device to perform the method according to the second aspect.

In a tenth aspect, an embodiment of the present invention provides a computer program, which includes computer software program instructions, which, when executed by the first PE device, cause the first PE device to perform the method according to the first aspect.

In an eleventh aspect, embodiments of the present invention provide another computer program, which includes computer software program instructions, which, when executed by the second PE device, cause the second PE device to perform the method according to the second aspect.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments or the background art of the present application, the drawings required to be used in the embodiments or the background art of the present application will be described below.

Fig. 1 is an architecture diagram of a communication system provided by an embodiment of the present invention;

FIG. 2 is a hardware diagram of a provider edge device according to an embodiment of the present invention;

fig. 3 is a schematic flowchart of a data transmission method according to an embodiment of the present invention;

fig. 4 is a block diagram of a provider edge device according to an embodiment of the present invention;

fig. 5 is a block diagram of another provider edge device according to an embodiment of the present invention.

Detailed Description

The terminology used in the description of the embodiments section of the present application is for the purpose of describing particular embodiments of the present application only and is not intended to be limiting of the present application.

Fig. 1 is a diagram illustrating an architecture of a communication system according to an embodiment of the present invention. As shown in fig. 1, the communication system 100 includes: CE device 101, first PE device 102, second PE device 103, and third PE device 104.

One side of the first PE device 102 and one side of the second PE device 103 are connected to the CE device 101, respectively, and the other side is connected to the third PE device 104. The CE device 101 has dual homing access to a first PE device 102 and a second PE device 103. The first PE device 102 and the second PE device 103, acting as a master-slave, forward data received from other forwarding devices (e.g., the third PE device 104) to the CE device 101, and forward data of the CE device 101 to other forwarding devices (e.g., the third PE device 104).

The first PE device 102 and the second PE device 103 deploy an E-Trunk control protocol, and the E-Trunk aggregation group includes a plurality of links from the first PE device 102 to the CE device 101 and a plurality of links from the second PE device 103 to the CE device 101. Normally, the downstream data is forwarded to the first PE device 102 and the second PE device 103, and since the second PE device 103 is not a master device, the second PE device 103 blocks the data locally and does not forward the data to the CE device 101.

When a link or node of the first PE device 102 fails, an interface between the first PE device 102 and the CE device 101 is disconnected (Down), the second PE device 103 is upgraded to a master device, the bottom blocking state is triggered to be opened, and the data packet sent by the third PE device 104 to the CE device 101 is forwarded to the CE device 101.

In order to ensure fast switching of Trunk, BFD is deployed between the first PE device 102 and the second PE device 103 and the CE device 101, and the BFD detects a Trunk interface or a Trunk member interface on the primary device, and when a link failure occurs between the first PE device 102 and the CE device 101, the second PE device 103 of the backup device can quickly sense through the BFD. For example, BFD establishes a session at first PE device 102 and second PE device 103 to detect a bidirectional forwarding path between first PE device 102 and second PE device 103 to serve upper layer applications. After the BFD session is established, the BFD packet may be periodically and quickly sent, and if the second PE device 103 serving as the standby device does not receive the BFD packet sent by the first PE device 102 serving as the main device within the detection time (for example, 10s), it is considered that the bidirectional forwarding path has a failure, and may trigger the E-Trunk switching, and the second PE device 103 is upgraded to the main device.

When there is more than one Trunk member port on each PE device and there are multiple single boards on the PE device, the Trunk member ports may be located on different single boards. When the BFD detection is executed on the PE equipment, a BFD state machine needs to be operated, the BFD detection realizes various processing functions based on the state machine, and the BFD state machine is also positioned on a single board. There are thus situations where: the single board where the Trunk member interface for receiving and sending the BFD packet is located is not the same single board as the single board running the BFD state machine, and for convenience of description, this case is named as a case where BFD runs on a cross-board Trunk in the embodiment of the present invention. For example, first PE device 102 includes 3 boards, which are board 1, board 2, and board 3, where the BFD state machine is located on board 1, and when board 1 fails (for example, board is reset or unit cannot work normally), board 1 cannot send a BFD packet, and since it takes a certain time (longer than time (for example, 10s) for second PE device to detect the BFD packet) for migrating the BFD state machine to another board that has not failed, second PE device 103 cannot receive the BFD sent by first PE device 102 within the detection time, second PE device 103 may determine that first PE device 102 fails, and second PE device 103 may execute a backup main process. After the second PE device 103 is upgraded to the master device, the second PE device 103 forwards the data packet sent by the third PE device 104 to the CE device 101, and the CE device 101 sends the data packet to the terminal. In fact, except for the failed single board 1, the first PE device 102 has other non-failed single boards 2 and 3 alive, where the single board 2 or the single board 3 may be configured to continue to receive the BFD packet, the first PE device 102 does not have Trunk Down, and the first PE device 102 may also use the non-failed single board to forward data to the CE device 101. The first PE device 102 also serves as a master device, and forwards the data packet sent by the third PE device 104 to the CE device 101, and the CE device 101 sends the data packet to the terminal. Thus, a terminal, such as a set-top-box (STB), is caused to receive two multicast streams for first PE device 102 and second PE device 103, thereby causing a video to be filmed. During this time, both first PE device 102 and second PE device 103 consider themselves to be the master of the E-Trunk. The dual master process continues until BFD renegotiates, at which stage the STB always takes the screen. The local spot test will screen up 30s +.

Or, if a single board running the BFD state machine on the second PE device 103 fails, the E-Trunk processing module of the second PE device 103 may also sense the Down of BFD, and further think that the Down is on the first PE device 102, and further link with the second PE device 103 to promote, which may also cause the terminal, e.g., a set-top box, to receive two multicast streams of the first PE device 102 and the second PE device 103, thereby causing a video screen splash.

Therefore, the problem that the BFD runs on the single board Trunk and the multicast service issues two multicast streams for a long time due to the BFD missing Down needs to be solved. Here, BFD false Down means: in addition to the failed board, other boards that have not failed on the first PE device 102 serving as the main device may operate the BFD state machine, receive and transmit BFD messages, and forward data, in this case, the first PE device 102 does not have Trunk Down, but the second PE device 103 may misunderstand that the first PE device 102 has failed because it does not receive the BFD message sent by the failed board by the first PE device 102 within the detection time.

In this application, the first PE device 102 needs to identify BFD false Down, the local end does not perform primary-backup switching due to BFD false Down, and notifies the second PE device 103 to restore the standby state after misjudging that the first PE device 102 has failed to perform primary-backup switching. Therefore, the video screen splash problem caused by the fact that the terminal receives two multicast streams due to the fact that the double main devices transmit data to the CE device 101 is avoided. As will be explained in detail in the following examples.

Referring to fig. 2, which is a schematic diagram of a hardware structure of a device according to an embodiment of the present invention, as shown in fig. 2, a Provider Edge (PE) device 200 includes a main control board 201, an interface board 202, and a switch network board 203.

The main control board 201 is used to complete functions of system management, device maintenance, protocol processing, etc., and controls data movement inside the provider edge device 200. In practical applications, the main control board 201 may be a Central Processing Unit (CPU), a general purpose processor, a Digital Signal Processor (DSP), an application-specific integrated circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, a transistor logic device, a hardware component, or any combination thereof. Which may implement or perform the various illustrative logical blocks, modules, and circuits described in connection with the disclosure. A processor may also be a combination of computing functions, e.g., comprising one or more microprocessors, a DSP and a microprocessor, or the like.

The switch board 203 is used to complete data exchange between the interface boards 202, i.e. the switch board 203 is used to exchange data inside the provider edge 200.

The interface board 202 is used to provide various traffic interfaces (e.g., an interface for E-Trunk) and to implement fast forwarding of data packets, i.e., for communication from other devices. For example, the interface board 202 is used to receive data transmitted by other devices and transmit data to other devices. The interface board 202 is also referred to as a board, a line card, or a service board, and the interface board 202 may be a board for operating a BFD state machine, a board for receiving and transmitting BFD messages, or a board for forwarding data.

In this embodiment, the provider edge device 200 may further include a memory, which may be used to store an implementation program of the data transmission method provided by the embodiment of the present invention on the provider edge device 200 side. For the implementation of the data transmission method provided in the embodiment of the present invention, please refer to the following method embodiments.

The main control board 201 may be used to read and execute computer readable instructions. Specifically, the main control board 201 may be configured to call a program stored in the memory, for example, an implementation program of the data transmission method provided in the embodiment of the present invention on the provider edge device 200 side, and execute instructions included in the program to implement the method related to the subsequent embodiment.

It should be noted that the provider edge device 200 shown in fig. 2 is only one implementation manner of the embodiment of the present application, and in practical applications, the provider edge device 200 may further include more or less components, which is not limited herein.

The structures of the first PE device 102, the second PE device 103, and the third PE device 104 shown in fig. 1 may all adopt the provider edge device 200 structure shown in fig. 2.

Based on the foregoing embodiments corresponding to the communication system 100 and the provider edge device 200, an embodiment of the present invention provides a data transmission method. Referring to fig. 3, a schematic flow chart of a data transmission method provided in an embodiment of the present invention is shown, where the data transmission method includes, but is not limited to, the following steps:

s301, the first PE device determines that the first single board fails.

S302, the second PE device determines that the first PE device has a single board fault.

And S303, the first PE device judges whether the first single board is the single board where the BFD state machine is located, if so, the step S304 is executed.

S304, the first PE device determines whether there is a second board that has not failed, and if yes, executes step S305.

S305, the first PE device sends a BFD message to the second PE device by the second single board, the second PE device receives the BFD message sent by the first PE device by the second single board without fault, and the BFD message is used for indicating that the second PE device does not carry out backup upgrading.

And S306, if the second PE device is subjected to backup upgrading, the second PE device is switched back to the backup device by the main device according to the BFD message.

And S307, if the second PE does not perform backup upgrading, the second PE equipment determines that the second PE equipment is the backup equipment according to the BFD message.

The execution sequence of steps S301 and S302 is not limited.

In this embodiment of the present invention, the first PE device may have multiple boards, and the second PE device may also have multiple boards. The BFD state machine of the first PE device operates on a board of the first PE device, and the BFD state machine of the second PE device operates on a board of the second PE device. The first PE device sends a BFD message to the second PE device by using a single board, and if the second PE device does not receive the BFD message sent by the first PE device within a detection time (e.g., 10 seconds), the second PE device determines that the first PE device has a failure, and starts a backup main process.

The first PE device may perform self-checking, that is, the first PE device may detect that a single board of itself fails, and may accurately determine which single board fails. When the first PE device determines that the first board has a failure, the first PE device determines whether the first board is a board running the BFD state machine, if so, the first PE device further identifies whether other second boards that have no failure are included, and if so, the first PE device is only the first board that has a failure, and not all boards have a failure, so the first PE device has no failure. In order to avoid upgrading the second PE device from the standby device to the main device, the first PE device needs to notify the second PE not to perform the standby upgrading main process. Specifically, the first PE device migrates the BFD state machine to the second board without failure, and after the BFD state machine successfully establishes a session (session), the first PE device sends a BFD message (e.g., an admin-down message) to the second PE device by using the second board without failure, so as to indicate that the second PE device does not perform backup upgrade. After receiving the BFD message sent by the first PE device using the second board that has not failed, the second PE device determines that the first PE device is only one board that has failed and that all boards have not failed, and returns the second PE device to the standby device. For example, if the second PE device is upgraded to the primary device at this time, the second PE device is switched from the primary device to the standby device again, and continues to block the data locally and does not continue to forward the data to the CE device. And if the second PE equipment is executing the standby upgrading main process at the moment, the second PE equipment cancels the upgrading to the main equipment. And if the second PE device does not start the standby main process at the moment, the second PE device does not perform the standby main process.

For example, the first PE device includes 3 boards, which are board 1, board 2, and board 3. The single board 1 runs a BFD state machine, and when the single board 1 fails, the second PE device does not receive a BFD message sent by the first PE device within a detection time (for example, 10s), and then the second PE device determines that the first PE device fails, and starts a backup upgrade main process. After determining that the single board 1 has a failure, the first PE device determines whether the single board 2 and the single board 3 have no failure, and if the single board 2 has no failure, the first PE device uses the single board 2 to operate the BFD state machine, and continues to use the single board 2 to send a BFD message (e.g., an admin-down message) to the second PE device after the BFD state machine establishes a session, so as to notify the second PE device not to perform the standby main process. And after receiving the admin-down message sent by the first PE device by adopting the single board 2, the second PE device returns back to the standby device.

If the first PE device identifies that the first PE device has other non-failed boards besides the failed board, the first PE device forwards data to the CE device by using the non-failed board, thereby ensuring continuity of communication and improving reliability of data transmission in link aggregation of the device.

And if the second PE equipment receives the BFD message sent by the first PE equipment by adopting the single board which is not failed, returning back to the standby equipment, continuously blocking the data locally and not continuously forwarding the data to the CE equipment, and avoiding the phenomenon of screen splash at the terminal caused by the fact that the CE receives the duplicate data.

To sum up, if the board where the first PE device fails is a board where the BFD state machine operates, and the first PE device further includes other second boards that do not fail, the first PE device may switch the BFD state machine to the second board, and send the BFD packet to the second PE device by using the second board, thereby notifying the second PE device not to perform the backup up main process, thereby avoiding a problem of dual main devices caused by the fact that the second PE device performs the backup up main for the failure of the first PE device by mistake, avoiding a problem of causing the CE to receive duplicate data, and improving reliability of data transmission in device link aggregation.

Fig. 4 is a block diagram of a provider edge device according to an embodiment of the present invention. As shown in fig. 4, the first provider edge device 40 includes: a judging unit 401 and a transmitting unit 402.

In this embodiment of the present invention, the determining unit 401 is configured to determine, if a first board of the first PE device fails, whether the first board is a board where a bidirectional forwarding detection BFD state machine is located;

a sending unit 402, configured to send a BFD packet to a second PE device by using the second board if the first board is the board where the BFD state machine is located and the first PE device includes a second board that does not have a fault, where the BFD packet is used to indicate that the second PE device does not perform backup.

In the present embodiment, the first provider edge device 40 is presented in the form of a functional unit. As used herein, a "unit" may refer to an ASIC, a processor and memory that execute one or more software or firmware programs, an integrated logic circuit, and/or other devices that may provide the described functionality. The first provider edge device 40 may take the form shown in fig. 2. The determining unit 401 may be implemented by the main control board 201 in fig. 2, and the sending unit 402 may be implemented by the interface board 202 in fig. 2.

Optionally, the sending unit 402 is further configured to forward the received service data to the customer edge CE device if the first board is the board where the BFD state machine is located and the first PE device includes the second board that has not failed.

It should be noted that, for the functions of each functional module in the first provider edge device 40 described in the embodiment of the present invention, reference may be made to the related description of the corresponding first PE device in the embodiment shown in fig. 3, which is not described herein again.

Fig. 5 is a schematic structural diagram of another provider edge device according to an embodiment of the present invention. As shown in fig. 5, the second provider edge device 50 includes: a determining unit 501, a receiving unit 502 and a fallback unit 503.

In this embodiment of the present invention, the determining unit 501 is configured to determine that a single board fault occurs in the first PE device;

a receiving unit 502, configured to receive a bidirectional forwarding detection BFD message sent by the first PE device by using a single board that has not failed;

a fallback unit 503, configured to switch, according to the BFD packet, the main device to a backup device if the second PE device has already performed backup upgrade;

the fallback unit 503 is further configured to determine, according to the BFD packet, that the second PE device is a standby device if the second PE device has not already been subjected to a standby service.

In the present embodiment, the second provider edge device 50 is presented in the form of a functional unit. As used herein, a "unit" may refer to an ASIC, a processor and memory that execute one or more software or firmware programs, an integrated logic circuit, and/or other devices that may provide the described functionality. The second provider edge device 50 may take the form shown in fig. 2. The determining unit 501 may be implemented by the main control board 201 in fig. 2, the receiving unit 502 may be implemented by the interface board 202 in fig. 2, and the rollback unit 503 may be implemented by the main control board 201 in fig. 2.

Optionally, the fallback unit 503 is configured to switch, according to the BFD packet, the master device to the standby device, and includes:

and stopping forwarding the received service data to the customer edge CE equipment.

It should be noted that, for the functions of each functional module in the second provider edge device 50 described in the embodiment of the present invention, reference may be made to the related description corresponding to the second PE device 50 in the embodiment shown in fig. 3, which is not described herein again.

The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied in hardware or may be embodied in a processor executing software program instructions. The software program instructions may consist of corresponding software modules that may be stored in RAM, flash memory, ROM, Erasable Programmable Read Only Memory (EPROM), Electrically Erasable Programmable Read Only Memory (EEPROM), registers, a hard disk, a removable hard disk, a compact disc read only memory (CD-ROM), or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. Of course, the storage medium may also be integral to the processor. The processor and the storage medium may reside in an ASIC. In addition, the ASIC may be located in a transceiver or a relay device. Of course, the processor and the storage medium may reside as discrete components in the first PE device or the second PE device.

Those skilled in the art will recognize that, in one or more of the examples described above, the functions described in connection with the embodiments of the invention may be implemented in hardware, software, firmware, or any combination thereof. When implemented in software, the functions may be stored on or transmitted over as one or more program instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a general purpose or special purpose computer.

The above embodiments are only intended to be illustrative of the embodiments of the present invention, and should not be construed as limiting the scope of the embodiments of the present invention, and any modifications, equivalent substitutions, improvements and the like made on the basis of the technical solutions of the embodiments of the present invention should be included in the scope of the embodiments of the present invention.

Claims

1. A method of data transmission, comprising:

if a first single board of first provider edge PE equipment fails, the first PE equipment judges whether the first single board is the single board where a Bidirectional Forwarding Detection (BFD) state machine is located;

if the first board is the board where the BFD state machine is located, and the first PE device includes the second board that has not failed, the first PE device migrates the BFD state machine to the second board, and the first PE device sends a BFD message to the second PE device by using the second board, where the BFD message is used to indicate that the second PE device does not perform backup upgrade.

2. The method of claim 1, further comprising:

if the first board is the board where the BFD state machine is located, and the first PE device includes the second board that has not failed, the first PE device forwards the received service data to the customer edge CE device.

3. A method of data transmission, comprising:

the second provider edge PE equipment determines that the first PE equipment has single board failure;

the second PE equipment receives a Bidirectional Forwarding Detection (BFD) message sent by the first PE equipment by adopting a single board which does not have a fault; the single board which does not have the fault comprises a BFD state machine which is transferred from the single board which has the fault;

if the second PE equipment is subjected to backup upgrading, the second PE equipment is switched back to the backup equipment by the main equipment according to the BFD message;

and if the second PE equipment does not carry out backup upgrading, the second PE equipment determines that the second PE equipment is the backup equipment according to the BFD message.

4. The method according to claim 3, wherein the second PE device is switched back to the standby device by the master device according to the BFD message, and the method comprises the following steps:

and the second PE equipment stops forwarding the received service data to the customer edge CE equipment.

5. A provider edge, PE, device, wherein the PE device is a first PE device, the first PE device comprising:

a determining unit, configured to determine, if a first board of the first PE device fails, whether the first board is a board where a bidirectional forwarding detection BFD state machine is located;

a sending unit, configured to migrate the BFD state machine to the second board if the first board is a board where the BFD state machine is located and the first PE device includes a second board that does not have a fault, and send a BFD packet to the second PE device by using the second board, where the BFD packet is used to indicate that the second PE device does not perform backup upgrade.

6. The PE device of claim 5, wherein the sending unit is further configured to forward the received service data to a customer edge CE device if the first board is a board where the BFD state machine is located and the first PE device includes a second board that does not have a failure.

7. A provider edge, PE, device, wherein the PE device is a second PE device, the second PE device comprising:

a determining unit, configured to determine that a single board fault occurs in the first PE device;

a receiving unit, configured to receive a bidirectional forwarding detection BFD packet sent by the first PE device by using a single board that has not failed; the single board which does not have the fault comprises a BFD state machine which is transferred from the single board which has the fault;

the rollback unit is used for switching the main equipment to the standby equipment according to the BFD message if the second PE equipment carries out standby upgrading;

and the rollback unit is further configured to determine that the second PE device is a standby device according to the BFD packet if the second PE device has not already been subjected to a standby master.

8. The PE device of claim 7, wherein the fallback unit is configured to switch back to the standby device from the primary device according to the BFD packet, and includes:

9. A communication system comprising a first provider edge PE device, a second PE device and a customer edge CE device, wherein the first PE device is the first PE device of claim 5 or 6 and the second PE device is the second PE device of claim 7 or 8.

10. A computer storage medium storing computer software program instructions which, when executed by a first provider edge, PE, device, cause the first PE device to perform the data transmission method of claim 1 or 2; alternatively, the program instructions, when executed by a second PE device, cause the second PE device to perform the data transmission method of claim 3 or 4.