CN113645312A

CN113645312A - Method and device for protecting sub-ring network link based on ERPS protocol

Info

Publication number: CN113645312A
Application number: CN202110979052.8A
Authority: CN
Inventors: 杜苏林; 杨冬
Original assignee: Fiberhome Telecommunication Technologies Co Ltd
Current assignee: Fiberhome Telecommunication Technologies Co Ltd
Priority date: 2021-08-25
Filing date: 2021-08-25
Publication date: 2021-11-12
Anticipated expiration: 2041-08-25
Also published as: CN113645312B

Abstract

The invention discloses a method and a device for protecting a sub-ring network link based on an ERPS protocol, wherein when a link where a port X is located is detected to have a fault, an SF fault message is generated, and whether switching equipment to which the port X belongs is RPL equipment is judged; if the switching equipment is not RPL equipment, the SF fault message is directly sent to the adjacent switching equipment through another port Y of the switching equipment; if the switching equipment is RPL equipment and the other port Y is a RPL link main port, switching the two port state and the ERPS protocol state of the switching equipment, and then sending the SF fault message to the adjacent switching equipment through the port Y. By the scheme, the ERPS protocol can normally run on the sub-ring network link, so that the ERPS protocol plays a complete service protection role on the sub-ring network link; meanwhile, the operation and maintenance cost is reduced.

Description

Method and device for protecting sub-ring network link based on ERPS protocol

Technical Field

The invention belongs to the technical field of link protection, and particularly relates to a method and a device for protecting a sub-ring network link based on an ERPS protocol.

Background

The ERPS (Ethernet Ring Protection Switching) is an Ethernet Ring network link layer technology with high reliability and stability. Through the ERPS protocol, when the Ethernet ring network has link failure, the communication path between each node on the ring network can be quickly recovered, and the convergence rate is high.

The ring network ERPS protocol processing means that a protocol state machine is controlled by receiving and sending ERPS protocol messages, and then the port forwarding state is controlled by the protocol state machine, so that the link service protection effect is realized. However, in some current network services, for reasons such as reducing the CPU load of some switching devices, these switching devices in the loop do not participate in the processing of the ERPS protocol, and at this time, other switching devices in the loop form a sub-ring network link, and it is necessary to complete the service protection of the sub-ring link by operating the ERPS protocol on the switching device on the sub-ring link.

In the scenario of the sub-ring network link, because the ERPS protocol packet can only run on the sub-ring network link but cannot transparently transfer the entire ring network link, when a link failure or failure recovery occurs, there is a problem that some switching devices cannot receive the ERPS protocol packet, so that the protocol state machine cannot perform port forwarding state control according to the received ERPS protocol packet, that is, the ERPS protocol cannot complete link switching by receiving the ERPS protocol packet, thereby causing the ERPS protocol to fail to perform a complete service protection function on the sub-ring link.

In view of the above, it is an urgent problem in the art to overcome the above-mentioned drawbacks of the prior art.

Disclosure of Invention

Aiming at the defects or the improvement requirements of the prior art, the invention provides a method and a device for protecting a sub-ring network link based on an ERPS protocol, and aims to perform message processing according to the role of equipment on the sub-ring network link and complete link protection switching, thereby solving the technical problem that the ERPS protocol cannot normally operate on the sub-ring network link in the traditional scheme.

To achieve the above object, according to an aspect of the present invention, there is provided a method for protecting a sub-ring network link based on an ERPS protocol, where the sub-ring network link includes a plurality of switching devices, and one of the switching devices is an RPL device; each switching device is provided with two ports, one port of the RPL device is an RPL link main port and is in a blocking state in an initial state, and the other ports are in a forwarding state in the initial state; when the ERPS protocol is run on the sub-ring network link, the sub-ring network link protection method specifically includes:

when detecting that a link of a port X is in fault, generating an SF fault message, and judging whether a switching device to which the port X belongs is an RPL device;

if the switching equipment is not RPL equipment, the SF fault message is directly sent to the adjacent switching equipment through another port Y of the switching equipment;

if the switching equipment is RPL equipment and the other port Y of the switching equipment is an RPL link main port, switching the two-port state and the ERPS protocol state of the switching equipment, and then sending the SF fault message to the adjacent switching equipment through the port Y.

Preferably, the generating an SF fault message when detecting that the link where the port X is located fails, and determining whether the switching device to which the port X belongs is an RPL device includes:

when the bottom driver detects that the link of the port X is in fault, the bottom driver informs an ERPS protocol module of the switching equipment to which the port X belongs, a protocol state machine processing module in the ERPS protocol module generates the SF fault message, and judges whether the switching equipment is RPL equipment.

Preferably, if the ERPS protocol state in the RPL device initial state is an idle state, the SF fault message is sent to an adjacent switching device through the port Y after the two port states of the switching device and the ERPS protocol state are switched, specifically:

switching the port X from an initial forwarding state to a blocking state, and switching the port Y from the initial blocking state to the forwarding state;

clearing the mac address forwarding table cached by the port X, and relearning the mac address forwarding table by the port Y according to the service flow direction;

switching the ERPS protocol state of the exchange equipment from an initial idle state to a protection state;

and switching the service flow from the original port X to the port Y according to the mac address forwarding table so as to send the SF fault message to the adjacent switching equipment through the port Y.

Preferably, the method for protecting a sub-ring network link further includes:

when the current switching equipment receives the SF fault message, a source mac address and a message receiving port number are obtained by analyzing the content of the SF fault message;

checking whether the source mac address is consistent with the mac address of the current switching equipment, if so, directly discarding the received SF fault message, and if not, continuously judging whether the current switching equipment is RPL equipment;

if the current switching equipment is not RPL equipment, forwarding the SF fault message through another port of the current switching equipment according to the analyzed port number of the received message;

and if the current switching equipment is RPL equipment, switching the state of two ports of the current switching equipment and the state of an ERPS protocol, and then forwarding the SF fault message through the other port of the current switching equipment.

Preferably, the method for protecting a sub-ring network link further includes:

when detecting that the link where the port X is located is recovered from the fault, the switching device to which the port X belongs simultaneously sends the NR fault recovery message to the port X and the port Y, and judges whether the switching device is an RPL device;

if the switching equipment is not RPL equipment, the NR fault recovery message is continuously sent;

if the switching equipment is RPL equipment, starting an RPL self-switching timing task to judge whether the current link is a sub-ring network link or not;

if not, the RPL self-switching timing task is stopped, if the link is a sub-ring network link, the RPL self-switching is carried out, so that the two port state and the ERPS protocol state of the switching equipment are switched back to the initial state, and the NR-RB message is simultaneously sent through the port X and the port Y.

Preferably, when detecting that the link where the port X is located has failed to recover, the switching device to which the port X belongs sends the NR failure recovery packet to the port X and the port Y at the same time, and determines whether the switching device is an RPL device, specifically:

when the bottom driver detects the fault recovery of the link where the port X is located, the bottom driver notifies an ERPS protocol module of the switching equipment to which the port X belongs, and a protocol state machine processing module in the ERPS protocol module sends the NR fault recovery message to the port X and the port Y at the same time, and judges whether the switching equipment is RPL equipment or not.

Preferably, the step of starting the RPL self-back-switch timing task to determine whether the current link is a sub-ring network link specifically includes:

starting the RPL self-switchback timing task to check whether the switching equipment receives the NR fault recovery message sent by the switching equipment in the self-switchback timing time;

if the switching equipment receives the NR fault recovery message sent by the switching equipment within the self-switching timing time, the switching equipment proves that the current link is not a sub-ring network link;

and if the switching equipment does not receive the NR fault recovery message sent by the switching equipment within the self-switching time, the current link is proved to be a sub-ring network link.

Preferably, within the self-cutback timing time, if the switching device receives an NR failure recovery packet or an SF failure packet sent by the remaining switching devices, the RPL self-cutback timing task is stopped, and corresponding processing is performed according to the type of the received ERPS protocol packet.

Preferably, the performing RPL self-switchback to switch the two port states and the ERPS protocol state of the switching device back to the initial state, and sending the NR-RB packet through the port X and the port Y at the same time specifically includes:

starting a WTR timer to perform RPL self-switching back so as to restore the port X from a blocking state to an initial forwarding state and restore the port Y from the forwarding state to the initial blocking state;

simultaneously sending NR-RB messages to the two ends through the port X and the port Y so as to inform other switching equipment on the sub-ring network link that the RPL link main port is recovered to be blocked;

and restoring the ERPS protocol state of the exchange equipment from the protection state to an initial idle state to complete the fault recovery processing.

According to another aspect of the present invention, an apparatus for protecting a sub-ring network link based on an ERPS protocol is provided, configured to complete the method for protecting a sub-ring network link according to the first aspect, where the apparatus includes an ERPS protocol module respectively set for each switching device, the ERPS protocol module includes a protocol state machine processing module and a protocol transceiving packet processing module, the protocol state machine processing module is configured to control a port state of each switching device in a sub-ring network link, and the protocol transceiving packet processing module is configured to implement message interaction between each switching device in the sub-ring network link;

the protocol state machine processing module and the protocol transceiving packet processing module are respectively connected with a bottom layer drive; when the bottom driver detects that a link of a port X is in fault, the bottom driver informs a protocol state machine processing module corresponding to switching equipment to which the port X belongs, the protocol state machine processing module generates an SF fault message, and judges whether the switching equipment is RPL equipment;

if the switching equipment is not RPL equipment, the protocol receiving and sending packet processing module sends the SF fault message to the adjacent switching equipment through another port Y of the switching equipment; if the switching device is an RPL device, the protocol state machine processing module switches the two port states and the ERPS protocol state of the switching device, and the protocol transmitting and receiving packet processing module transmits the SF fault message to the adjacent switching device through the port Y.

Generally, compared with the prior art, the technical scheme of the invention has the following beneficial effects: in the link protection method of the sub-ring network provided by the invention, when a link where a certain port is located has a fault, the link protection switching can be finished by processing according to the role of the current switching equipment configured by the network, directly sending an SF fault message through another port if the link is not RPL equipment, switching the state of two ports of the current switching equipment and the state of an ERPS protocol if the link is RPL equipment, and then sending the SF fault message through another port. By the scheme, the ERPS protocol can normally run on the sub-ring network link, so that the ERPS protocol plays a complete service protection role on the sub-ring network link; meanwhile, on the premise of not needing to add configuration commands and function switches, the method is compatible with the original existing network environment deployment, and the operation and maintenance cost is reduced.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments of the present invention will be briefly described below. It is obvious that the drawings described below are only some embodiments of the invention, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.

Fig. 1 is a flowchart of a process of a protocol state machine when a link failure occurs according to an embodiment of the present invention;

fig. 2 is a link networking diagram of a sub-ring network based on an ERPS protocol according to an embodiment of the present invention;

fig. 3 is a flowchart of processing a protocol transceiving message when a link failure occurs according to an embodiment of the present invention;

fig. 4 is a flowchart of processing of an RPL device when a link failure is recovered according to an embodiment of the present invention;

fig. 5 is a diagram of a sub-ring network link protection device based on an ERPS protocol according to an embodiment of the present invention;

fig. 6 is a flowchart of a processing performed by a link protection device based on a sub-ring network when a link failure occurs according to an embodiment of the present invention;

fig. 7 is a flowchart of a processing performed by a link protection device based on a sub-ring network when a link failure occurs according to an embodiment of the present invention;

fig. 8 is a flowchart of a processing performed by a link protection device based on a sub-ring network when a link failure is recovered according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other. The invention will be described in detail below with reference to the figures and examples.

Example 1

In order to solve the technical problem that the ERPS protocol cannot normally operate on the sub-ring network link, the embodiment of the invention provides a sub-ring network link protection method based on the ERPS protocol, which mainly comprises two scenes: the first is that when the link fails, the link protection switching is needed; the second is that when the link failure is recovered, the link needs to be restored to the initial state. When a link fails, the port state can be processed according to the device role configured by the network, and then an SF failure message is sent to complete the link protection switching; when the link failure is recovered, a self-switching back processing mechanism is added to restore the port state, and the recovery switching of the link is completed by combining the processing of the protocol state machine.

The sub-ring link usually includes a plurality of connected switching devices, each switching device has two ports, the state of each port is divided into a blocking state (i.e., block) and a forwarding state (i.e., unblock), and the ERPS protocol is a protection protocol applied to the link layer of the ethernet ring. The invention is to normally operate the ERPS protocol in the sub-Ring network Link, the device type of operating the ERPS protocol is divided into RPL (Ring Protection Link) device and non-RPL device, the port type of the switching device is divided into RPL Link main port (RPL owner port) and common port (common port), one of the switching devices is configured to be RPL device, one of the ports of the RPL device is configured to be RPL Link main port, the rest ports are common ports, namely only one RPL Link main port is arranged in the whole loop, so that the service Protection switching can be realized by using the RPL Link main port as a standby port in the subsequent ERPS protocol.

Each switching device in the sub-ring network link carries out communication interaction through an ERPS protocol message, wherein the ERPS protocol message is divided into SF (Signal Fail, namely Signal failure) fault message, NR (No Request, namely No Request) fault recovery message, NR-RB (No Request-RPL Block, namely No Request-environment-friendly protection link blocking) message and other types; wherein, the SF fault message indicates that the network has a fault, the NR fault recovery message indicates that the network is in a normal state, and the NR-RB message indicates that the RPL link main port is in a blocking state. In an initial state, that is, an initial stage of stable operation of the ERPS, an ERPS protocol state of the RPL device is an IDLE state (that is, an IDLE state), the RPL link main port is a blocking state, and the remaining ports are all in a forwarding state.

Based on the above configuration, the embodiment of the present invention is mainly developed around a first application scenario (i.e., link failure), and when an ERPS protocol is run on a sub-ring network link, a sub-ring network link protection method is specifically shown in fig. 1, and mainly includes the following steps:

step 101, when detecting that a link where a port X is located has a fault, generating an SF fault message, and determining whether a switching device to which the port X belongs is an RPL device.

When a link where a certain port X on a sub-ring network link is located fails, a corresponding failure can be detected through a bottom layer driver, the switching equipment to which the port X belongs is informed, and SF failure messages are generated by the switching equipment and sent to adjacent switching equipment. Because the current link is a sub-ring network link, the ERPS protocol packet cannot be transmitted through the entire ring link, and therefore before the switching device sends the SF fault packet, the protocol state machine needs to check and determine whether the switching device is an RPL device, so as to perform corresponding processing according to the role of the device in the following. If the RPL device is the RPL device, step 103 is executed, and if the RPL device is not the RPL device (i.e., the non-RPL device), step 102 is executed, which will be described later.

Step 102, if the switching device is not an RPL device, the SF fault message is directly sent to the adjacent switching device through another port Y of the switching device.

For convenience of description, the two ports of the switching device are referred to herein as port X and port Y, respectively. Therefore, when the link where the port X is located fails, if the switching device is not an RPL device, the link protection switching cannot be performed, and at this time, the switching device directly sends the SF fault message to the adjacent switching device through the configured port Y, so as to ensure that the adjacent device in the link receives the SF fault message.

Step 103, if the switching device is an RPL device and another port Y of the switching device is an RPL link master port, switching the two port state and the ERPS protocol state of the switching device, and then sending the SF fault message to an adjacent switching device through the port Y.

If the switching device is an RPL device and the port Y of the switching device is the RPL link master port configured in the foregoing, then the SF fault packet needs to be sent after the RPL device performs link protection switching, and the specific process is as follows:

switching the port X from an initial forwarding state to a blocking state, and switching the port Y from the initial blocking state to the forwarding state; clearing the mac address forwarding table cached by the port X, and relearning the mac address forwarding table by the port Y according to the service flow direction; switching the ERPS protocol state of the exchange equipment from an initial idle state to a protection state; if a WTR (Wait To Restore) timer is started, the WTR timer needs To be stopped, and the SF fault message is sent To an adjacent switching device through the port Y; and finally, switching the service flow from the original port X to the port Y according to the mac address forwarding table, so as to prevent the loss of the service flow data, thereby playing a role in link protection. The mac address forwarding table stores the mapping relationship between the source mac address and the port of the actual service, and can be used for determining the corresponding port number when forwarding the service traffic, so as to find the corresponding port.

As shown in fig. 2, in a specific embodiment, a switch and three OLT (Optical Line Terminal) devices form a ring network link, but in the entire ring network link, the switch does not configure a relevant port of the ERPS protocol and does not participate in relevant processing of the ERPS protocol message, but forms a sub-ring network link by three devices, namely, OLT1, OLT2, and OLT3, and the ERPS protocol runs in the sub-ring network link. Wherein OLT1 has P1 port and P2 port, OLT2 has P3 port and P4 port, OLT3 has P5 port and P6 port; OLT1 is configured as an RPL device, and OLT2 and OLT3 are non-RPL devices; the P1 port is the RPL link main port, and the rest ports are common ports. The OLT1 is used as an RPL device, the ERPS protocol state in its initial state is an idle state, the P1 port is used as an RPL link master port, its initial state is a blocking state, and the rest ports are all forwarding states. Based on the configuration, by operating the ERPS protocol on the sub-ring network link, when the sub-ring network link fails, the service protection function on the sub-ring network link can be achieved. The method comprises the following specific steps:

assuming that a link where the P2 port is located in fig. 2 fails, when the underlying driver detects that the link where the P2 port is located fails, the underlying driver notifies the OLT1, the OLT1 generates an SF failure message, and the protocol state machine determines whether the current OLT1 is an RPL device. If the equipment is non-RPL equipment, the SF fault message is directly sent through a P1 port; if the device is an RPL device, the SF fault message is sent through a P1 port after the link protection switching is required. According to the networking scenario in fig. 2, the OLT1 device to which the P2 port belongs is an RPL device, so when a link where the P2 port is located fails, the following link protection switching operations are performed: switching the P2 port from the forwarding state to the blocking state, and switching the P1 port from the blocking state to the forwarding state; clearing the mac address forwarding table cached by the P2 port, and relearning the mac address forwarding table by the P1 port according to the traffic flow; stopping the WTR timer if the WTR timer is started; and finally, the service flow is switched to a P1 port according to the mac address forwarding table, and an SF fault message is sent to the OLT3 equipment through the P1 port, so that the service protection switching of the link is completed.

With the method for protecting a link of a sub-ring network provided in the embodiment of the present invention, when a link of a port in a link of a sub-ring network fails, processing may be performed according to a role of a current switching device configured by a network, if the current switching device is not an RPL device, an SF failure message may be directly sent through another port, and if the current switching device is an RPL device, a state of two ports of the current switching device and an ERPS protocol state may be switched, and then an SF failure message may be sent through another port, thereby completing link protection switching. Therefore, the ERPS protocol can normally run on the sub-ring network link, so that the ERPS protocol plays a complete service protection role on the sub-ring network link; meanwhile, on the premise of not needing to add configuration commands and function switches, the method is compatible with the original existing network environment deployment, and the operation and maintenance cost is reduced.

Example 2

In the above embodiment 1, when the bottom layer driver detects a link failure, the corresponding switching device generates an SF failure message and sends the SF failure message to the adjacent switching device; on this basis, also in a link failure scenario, the embodiment of the present invention further uses the switching device that receives the SF failure message as the current switching device, and introduces the operation process after the current switching device receives the SF failure message.

With reference to fig. 3, on the basis of the foregoing embodiment 1, the method for protecting a sub-ring network link further includes:

step 201, when the current switching device receives the SF fault message, the source mac address and the message receiving port number are obtained by performing content analysis on the SF fault message. After the SF fault message is received through the message receiving port, which port the current switching device receives the SF fault message through can be determined.

Step 202, checking whether the source mac address is consistent with the mac address of the current switching device, if so, directly discarding the received SF fault message, and if not, continuously judging whether the current switching device is an RPL device;

after parsing the packet to obtain a source mac address and a packet port number, the current switching device checks whether the source mac address is consistent with the mac address of the current switching device. If the source mac address is consistent with the mac address of the current switching equipment, indicating that the current equipment receives the SF fault message sent by the current equipment, directly discarding the received SF fault message; since the current link is a sub-ring network link, the SF fault message sent by the current link cannot be received when the ERPS protocol is operated, which is mainly used in a full-ring network link scenario and is not described herein. If the mac address of the source is not consistent with the mac address of the current switching device, it indicates that the current device receives SF fault messages sent by other switching devices on the sub-ring network link, and at this time, the protocol state machine needs to further determine whether the current switching device is an RPL device, so as to perform corresponding processing according to the device role in the following. If the RPL device is the RPL device, step 204 is executed, and if the RPL device is not the RPL device, step 203 is executed, which will be described later.

Step 203, if the current switching device is not an RPL device, forwarding the SF fault message through another port of the current switching device according to the analyzed port number of the received message.

For example, assuming that two ports of the current switch device are respectively marked as a port X 'and a port Y', and the port number of the analyzed received message is X ', when the current switch device is not an RPL device, the SF fault message is directly forwarded to an adjacent switch device through the port Y', so that it is ensured that other switch devices on a sub-ring network link can receive the SF fault message.

Step 204, if the current switching device is an RPL device, after switching the two port state and the ERPS protocol state of the current switching device, forwarding the SF fault message through another port of the current switching device.

If the current switching device is an RPL device and another port Y' is the RPL link master port configured in the foregoing, at this time, the SF fault packet needs to be forwarded after performing link protection switching by using the RPL device, and the process is similar to that in embodiment 1, and specifically follows: switching the port X 'from an initial forwarding state to a blocking state, and switching the port Y' from the initial blocking state to the forwarding state; the mac address forwarding table cached by the port X 'is cleared, and the port Y' learns the mac address forwarding table again according to the service flow direction; switching the ERPS protocol state of the current exchange equipment from an initial idle state to a protection state; and finally, switching the service flow from the original port X ' to the port Y ' according to the new mac address forwarding table, and forwarding the SF fault message to the adjacent switching equipment through the port Y ', so that the link protection effect can be achieved.

Continuing to take the networking scenario shown in fig. 2 as an example, when a link where a P2 port is located fails, the SF fault message is sent from a P1 port, and a P5 port of the OLT3 receives the SF fault message; the OLT3 obtains a source mac address and a message receiving port number P5 by analyzing the message content, compares the analyzed source mac address with the mac address of the OLT3, and further determines whether the OLT3 is an RPL device if the two are inconsistent, and directly forwards the SF fault message through the P6 port to notify an adjacent switching device of the OLT3 because the OLT3 is a non-RPL device; in this way, if the adjacent exchange equipment runs the ERPS protocol, the processing is required to be carried out in the same way, and if the ERPS protocol is not run, the message processing is terminated.

By the link protection method of the sub-ring network provided by the embodiment of the invention, when a certain switching device in the link of the sub-ring network receives the SF fault message, the SF fault message can be processed according to the role of the current switching device configured by the network, if the SF fault message is not the RPL device, the SF fault message is directly forwarded through another port, if the SF fault message is the RPL device, the state of the two ports of the current switching device and the state of the ERPS protocol are switched, and then the SF fault message is sent through another port, thereby completing the link protection switching. Therefore, the ERPS protocol can normally run on the sub-ring network link, so that the ERPS protocol plays a complete service protection role on the sub-ring network link.

Example 3

On the basis of the foregoing embodiment 1 and embodiment 2, the embodiment of the present invention is further developed around a second application scenario (i.e., link failure recovery), where both the failed port and the RPL main link port need to be recovered to the initial state, and the ERPS protocol state of the RPL device also needs to be recovered to the initial state. Based on the above principle, when the ERPS protocol is run on the sub-ring network link, the method for protecting the sub-ring network link provided by the embodiment of the present invention is specifically shown in fig. 4, and mainly includes the following steps:

step 301, when detecting that the link where the port X is located has failed to recover, the switching device to which the port X belongs sends the NR failure recovery packet to both the port X and the port Y, and determines whether the switching device is an RPL device.

When the link fault of the port X on the sub-ring network link is recovered, the corresponding fault recovery can be detected through the bottom layer drive, the switching equipment to which the port X belongs is informed, and the switching equipment generates an NR fault recovery message and simultaneously sends the NR fault recovery message to two ports of the switching equipment. Since the current link is a sub-ring network link, the protocol state machine needs to check and determine whether the switching device is an RPL device first, so as to perform corresponding processing according to the role of the device in the following. If the RPL device is the RPL device, step 303 is executed, and if the RPL device is not the RPL device, step 302 is executed, which will be described later.

Step 302, if the switching device is not an RPL device, the NR failure recovery packet is continuously sent without any other processing.

Step 303, if the switching device is an RPL device, starting an RPL self-back-off timing task to determine whether the current link is a sub-ring network link. The method comprises the following specific steps:

starting the RPL self-switchback timing task, wherein the RPL self-switchback timing task is mainly used for checking an ERPS protocol message received by the switching equipment within a preset self-switchback timing time, and here, mainly checking whether the switching equipment receives the NR fault recovery message sent by the switching equipment within the self-switchback timing time. If the switching equipment receives the NR fault recovery message sent by the switching equipment within the self-switching timing time, the switching equipment proves that the current link is not a sub-ring network link but a full-ring network link. And if the switching equipment does not receive the NR fault recovery message sent by the switching equipment within the self-switching time, the current link is proved to be a sub-ring network link. The total time length of the NR fault recovery packet passing through the link of the full-ring network generally does not exceed 1 second, and therefore, in a specific embodiment, the self-switching timing time may be set to about 3 seconds.

And 304, if the link is not the sub-ring network link, stopping the RPL self-switchback timing task, if the link is the sub-ring network link, performing the RPL self-switchback so as to switch the two port states and the ERPS protocol state of the switching equipment back to the initial state, and simultaneously sending the NR-RB message through the port X and the port Y.

Within the self-switching timing time, if the switching device receives the NR failure recovery packet sent by itself, it is verified that the current link is not a sub-ring network link but a full ring network link, at this time, the RPL self-switching timing task needs to be stopped, and processing is performed according to a processing flow of receiving packets by the full ring network link, which is not described herein again. Further, within the self-cutback timing time, if the switching device receives an NR failure recovery packet or an SF failure packet sent by the other switching devices, the RPL self-cutback timing task also needs to be stopped, and corresponding processing is performed according to the type of the received ERPS protocol packet. Wherein, if an SF fault message is received, the specific processing procedure can refer to embodiment 1; if an NR fault recovery packet is received, the specific processing procedure may refer to embodiment 2.

In the self-switching time, if the switching device does not receive the NR failure recovery packet sent by itself, and it is verified that the current link is a sub-ring network link, there may also be a case that the RPL device cannot receive the NR failure recovery packet, so that the ERPS protocol state of the RPL device is always in a protection state after failure recovery, and the port X of the failure recovery is always in a blocking state. Therefore, in the embodiment of the present invention, an RPL self-switching mechanism is added to the sub-ring network link, that is, the port state and the ERPS protocol state are restored to the initial state after the link is restored, and the specific process is as follows:

when the self-switchover timing time expires, starting a WTR timer to perform RPL self-switchover so as to restore the port X from a blocking state to an initial forwarding state and restore the port Y from the forwarding state to the initial blocking state; then, the NR-RB messages are simultaneously sent to the two ends through the port X and the port Y so as to inform the rest of switching equipment on the sub-ring network link that the RPL link main port is recovered to be blocked; and at the same time, the ERPS protocol state of the exchange equipment is restored from the protection state to the initial idle state, and the fault recovery processing is completed.

Continuing with the networking scenario shown in fig. 2 as an example, when the bottom layer driver detects that the link where the P2 port is located has failed to recover, the OLT1 is notified, and the OLT1 generates an NR failure recovery message and sends the NR failure recovery message to the P1 port and the P2 port at the same time, at this time, the protocol state machine may determine whether the OLT1 device is an RPL device. If not, the NR fault recovery message is continuously sent without other processing; if the RPL equipment is the RPL equipment, the fault recovery processing is needed. Since the OLT1 is an RPL device, the OLT1 device needs to start an RPL self-switching timing task while sending an NR failure recovery message, and determines whether the current link is a sub-ring network link. Because the current link is a sub-ring network link, when the self-switching task timer expires, the WTR timer needs to be started to perform RPL self-switching processing, the P2 port is restored to an initial forwarding state, and the P1 port is restored to an initial blocking state; then, NR-RB messages are sent to the two ends simultaneously through the P1 port and the P2 port, and other switching devices on the sub-ring network link are informed that the RPL link main port is recovered to be blocked; meanwhile, the ERPS protocol state of the OLT1 device is restored to the initial idle state, thereby completing the fault recovery process.

By the link protection method for the sub-ring network provided by the embodiment of the invention, when the link failure in the sub-ring network link is recovered, the link failure can be processed according to the role of the current switching equipment configured by the network, if the link failure is not RPL equipment, the NR failure recovery message is continuously sent, if the link failure is RPL equipment and the current link is a sub-ring network link, an RPL self-switching mechanism is introduced, the two port state and the ERPS protocol state of the current switching equipment are restored to the initial state, and the NR-RB message is simultaneously sent through the two ports, so that the failure recovery processing is completed. Therefore, the ERPS protocol can normally run on the sub-ring network link, so that the ERPS protocol plays a complete service protection role on the sub-ring network link; meanwhile, on the premise of not needing to add configuration commands and function switches, the method is compatible with the original existing network environment deployment, and the operation and maintenance cost is reduced.

Example 4

On the basis of the foregoing embodiments 1 to 3, an embodiment of the present invention further provides a sub-ring network link protection device based on an ERPS protocol, which can be used to implement the sub-ring network link protection methods in embodiments 1 to 3.

With reference to fig. 5, the link protection device of the sub-ring network includes an ERPS protocol module respectively disposed corresponding to each switching device, where the ERPS protocol module mainly includes a protocol state machine processing module and a protocol transceiving packet processing module, and the protocol state machine processing module and the protocol transceiving packet processing module are respectively connected to the bottom layer driver. The protocol state machine processing module is the core of the protocol state machine and is mainly used for controlling the port state of each switching device in the sub-ring network link; the protocol receiving and sending packet processing module is mainly used for receiving and sending ERPS protocol messages so as to realize message interaction among all switching devices in the sub-ring network link; the service protection switching function of the sub-ring network link can be realized by combining the protocol state machine processing module and the protocol receiving and sending packet processing module.

The interactive content of the protocol state machine processing module and the bottom layer driver mainly comprises: when the link fails or recovers, the bottom layer driver informs the protocol state machine processing module, and the protocol state machine processing module sets the forwarding or blocking state of the port through the bottom layer driver; the interactive content of the protocol state machine processing module and the protocol transmitting and receiving packet processing module mainly comprises: when the protocol state machine changes, the sending processing and the receiving analysis inform the protocol state machine of the change; the interactive content of the protocol transmitting and receiving packet processing module and the bottom layer driver is mainly as follows: the receiving and sending of the ERPS protocol message need to be processed by the bottom layer driver.

Based on the link protection device of the sub-ring network, the embodiments of the present invention further introduce the link protection method of the sub-ring network in embodiments 1 to 3.

With reference to fig. 6, in a link failure scenario corresponding to embodiment 1, assuming that a link where a port X on a link of a sub-ring network is located fails, a method for protecting a link of a sub-ring network specifically includes:

step 401, when the bottom layer driver detects that the link where the port X is located has a fault, the bottom layer driver notifies the ERPS protocol module corresponding to the switching device to which the port X belongs.

Step 402, the corresponding protocol state machine processing module generates an SF fault message and determines whether the switching device is an RPL device. If the switching device is not an RPL device, go to step 403; if the switching device is an RPL device, steps 404 and 405 are performed.

Step 403, the protocol state machine processing module notifies the protocol transceiving packet processing module, and the protocol transceiving packet processing module sends the SF fault message to an adjacent switching device through another port Y of the switching device.

Step 404, the protocol state machine processing module switches the two port states of the switching device and the ERPS protocol state, that is, performs link protection switching, specifically: switching the port X into a blocking state, switching the port Y into a forwarding state, clearing the mac address forwarding table cached by the port X, relearning the mac address forwarding table by the port Y according to the service flow direction, and switching the ERPS protocol state of the switching equipment into a protection state.

Step 405, after the link protection switching is completed, the protocol transceiving packet processing module sends the SF fault message to the adjacent switching device through another port Y.

With reference to fig. 7, in the link failure scenario corresponding to embodiment 2, the method for protecting a link of a sub-ring network specifically includes:

step 501, when the protocol transceiving packet processing module of the current switching device receives the SF fault message, the protocol transceiving packet processing module obtains a source mac address and a message transceiving port number by analyzing message contents, and sends the source mac address and the message transceiving port number to the protocol state machine processing module of the current switching device.

Step 502, the protocol state machine processing module checks whether the source mac address is consistent with the mac address of the current switching device; if yes, go to step 503; if not, step 504 is performed.

Step 503, the protocol transmit-receive packet processing module directly discards the SF fault message without forwarding the message.

Step 504, the protocol state machine processing module continues to determine whether the current switching device is an RPL device. If the device is an RPL device, executing step 505 and then executing step 506; if not, step 506 is performed directly.

Step 505, the protocol state machine processing module performs link protection switching processing, specifically: switching the received SF fault message port X 'to a blocking state, switching the other port Y' to a forwarding state, clearing the mac address forwarding table cached by the port X ', relearning the mac address forwarding table by the port Y' according to the service flow direction, and switching the ERPS protocol state of the current switching equipment to a protection state.

Step 506, the protocol packet receiving and sending processing module forwards the SF fault message through another port of the current switching device according to the analyzed port number of the received message.

With reference to fig. 8, in the scenario of recovering from a link failure corresponding to embodiment 3, assuming that a link failure at a port X on a link of a sub-ring network is recovered, a method for protecting a link of a sub-ring network specifically includes:

step 601, when the underlying driver detects the failure recovery of the link where the port X is located, notifying an ERPS protocol module of the switching device to which the port X belongs.

Step 602, the corresponding protocol state machine processing module sends the NR fault recovery packet to the port X and the port Y at the same time.

Step 603, the protocol state machine processing module determines whether the switching device is an RPL device. If the switching device is not an RPL device, go to step 604; if the switching device is an RPL device, step 605 is performed.

Step 604, the protocol state machine processing module continuously sends the NR fault recovery packet without performing other processing.

Step 605, the protocol state machine processing module starts an RPL self-switchback timing task, and determines whether the current link is a sub-ring network link. If the protocol transceiving packet processing module receives an NR failure recovery packet sent by the device itself within the self-switching time, which proves that the current link is not the sub-ring network link, then step 606 is executed; if the protocol transceiving packet processing module does not receive the NR failure recovery packet sent by the self device within the self-switching time, it proves that the current link is the sub-ring network link, then step 607 is executed.

Step 606, the protocol state machine processing module stops the RPL self-switchback timing task and processes according to the NR fault recovery message flow.

Step 607, the protocol state machine processing module starts the WTR timer to perform RPL self-switchback when the self-switchback task timer expires, and further restores the port X to the initial forwarding state, restores the port Y to the initial blocking state, and simultaneously sends NR-RB messages to both ends through the port X and the port Y, so as to notify the remaining switching devices on the sub-ring network link that the RPL link main port has recovered blocking; at the same time, the ERPS protocol state of the exchange equipment is restored to the initial idle state, and the fault recovery processing is completed.

With the link protection device for a sub-ring network provided in the embodiment of the present invention, when a link where a port in a sub-ring network link is located fails, the protocol state machine processing module may perform processing according to a role of a current switching device configured by a network, and if the port is an RPL device, the protocol state machine processing module switches a state of two ports of the current switching device and an ERPS protocol state, thereby completing link protection switching; when the link failure in the sub-ring network link is recovered, the protocol state machine processing module can also process the role of the current switching equipment configured by the network, if the current link is the sub-ring network link, an RPL self-switching mechanism is introduced, the protocol state machine processing module restores the two port states of the current switching equipment and the ERPS protocol state to the initial state, and simultaneously sends an NR-RB message through the two ports to complete the failure recovery processing. Therefore, the ERPS protocol can normally run on the sub-ring network link, so that the ERPS protocol plays a complete service protection role on the sub-ring network link; meanwhile, on the premise of not needing to add configuration commands and function switches, the method is compatible with the original existing network environment deployment, and the operation and maintenance cost is reduced.

It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims

1. A sub-ring network link protection method based on ERPS protocol is characterized in that the sub-ring network link comprises a plurality of switching devices, and one of the switching devices is RPL device; each switching device is provided with two ports, one port of the RPL device is an RPL link main port and is in a blocking state in an initial state, and the other ports are in a forwarding state in the initial state; when the ERPS protocol is run on the sub-ring network link, the sub-ring network link protection method specifically includes:

2. The method for protecting a sub-ring network link based on an ERPS protocol according to claim 1, wherein the generating an SF failure message when detecting that a link where a port X is located fails, and determining whether a switching device to which the port X belongs is an RPL device specifically includes:

3. The method for protecting a sub-ring network link based on an ERPS protocol according to claim 1, wherein if an ERPS protocol state in the RPL device initial state is an idle state, the SF fault packet is sent to an adjacent switch device through the port Y after the two port state of the switch device and the ERPS protocol state are switched, and specifically:

4. The ERPS protocol-based sub-ring network link protection method of claim 1, wherein the sub-ring network link protection method further comprises:

5. The ERPS protocol-based sub-ring network link protection method of claim 1, wherein the sub-ring network link protection method further comprises:

6. The method for protecting a sub-ring network link based on an ERPS protocol according to claim 5, wherein when it is detected that the link where the port X is located has failed to recover, the switch device to which the port X belongs sends the NR failure recovery packet to the port X and the port Y at the same time, and determines whether the switch device is an RPL device, specifically:

7. The method for protecting a sub-ring network link based on an ERPS protocol of claim 5, wherein the task of starting the RPL self-loop-back-switch to determine whether the current link is a sub-ring network link specifically comprises:

8. The method according to claim 7, wherein in the self-switchback timing time, if the switching device receives an NR failure recovery packet or an SF failure packet sent by the remaining switching devices, the RPL self-switchback timing task is stopped, and corresponding processing is performed according to the type of the received ERPS protocol packet.

9. The method for protecting a sub-ring network link based on an ERPS protocol according to claim 5, wherein the RPL self-switchback is performed to switch the two port states of the switching device and the ERPS protocol state back to an initial state, and the NR-RB packet is sent through the port X and the port Y at the same time, specifically:

10. A sub-ring network link protection device based on an ERPS protocol is characterized by comprising an ERPS protocol module which is respectively arranged corresponding to each switching device, wherein the ERPS protocol module comprises a protocol state machine processing module and a protocol transceiving packet processing module, the protocol state machine processing module is used for controlling the port state of each switching device in a sub-ring network link, and the protocol transceiving packet processing module is used for realizing message interaction between each switching device in the sub-ring network link;