WO2018171745A1

WO2018171745A1 - Protection switching method and device for ring network

Info

Publication number: WO2018171745A1
Application number: PCT/CN2018/080311
Authority: WO
Inventors: 高菲
Original assignee: 中兴通讯股份有限公司
Priority date: 2017-03-23
Filing date: 2018-03-23
Publication date: 2018-09-27
Also published as: KR20190124314A; CN108632121A

Abstract

Disclosed are a protection switching method and device for ring network, relating to the field of communications and used for solving the problem in the prior art of not being able to realise corresponding service protection in an SD scenario such as a blockage occurring in a link, or a frame error. The method comprises: end nodes of a link respectively detecting whether signal degradation has occurred in the link; and when signal degradation has occurred in the link, the corresponding node executing a corresponding protection switching operation.

Description

Protection switching method and device for ring network

Technical field

The present disclosure relates to the field of communications technologies, and in particular, to a protection switching method and apparatus for a ring network.

Background technique

The ring network protection protocol ERPS (Ethernet Ring Protection Switching) and the switching mechanism (g.8032) in the Ethernet transmission network implement fast (<50ms) protection switching of the Ethernet ring topology service.

However, the current ERPS only implements a protection switching trigger mechanism that triggers SF (signal fail), such as port down and fiber break, and performs fast protection switching for services within 50 ms, and SD for congestion and error frames on the link. (signal degrade, signal degradation) situation can not achieve the corresponding business protection.

Summary of the invention

The technical problem to be solved by the present disclosure is to provide a protection switching method and device for a ring network, which solves the problem that the corresponding service protection cannot be realized in the prior art for the SD situation such as congestion and frame error of the link.

In one aspect, the present disclosure provides a protection switching method for a ring network, including: an end node of a link detects whether a signal degradation occurs on a link, respectively; and in a case where signal degradation occurs on the link, the corresponding node performs The corresponding protection switching operation.

Optionally, the end nodes of the link respectively detect whether the link has signal degradation includes: the end nodes of the link respectively receive a ring link state monitoring message of the link oam, where the ring link state monitoring message carries a frame event parameter; the end node determines, according to the frame event parameter, whether signal degradation occurs on the link.

Optionally, before the end node of the link based on the signal failure respectively detects whether the link has signal degradation, the method further includes: adding a processing mechanism for signal degradation in the ring network protection state machine and modifying the basis The request/status bit value of the ring-protected protocol message of the signal failure, so that the ring network protection state machine and the ring network protection protocol message are compatible with the processing of signal degradation.

Optionally, adding a processing mechanism for signal degradation in the ring network protection state machine based on the signal failure and modifying the request/status bit value of the ring network protection protocol message based on the signal failure includes: in the ring network protection request/ Adding local signal degradation local SD, local signal degradation clearing local clear SD, and ringing network automatic protection switching R-APS-SD item based on signal degradation in the status priority list; wherein the R-APS-SD item is used in the current If the end node is in the local SD state, the current end node notifies the neighboring node that the current link is in a signal degradation state by using the modified ring network protection protocol packet, and the ring network protection protocol packet corresponds to the corresponding The request/status location is a signal degradation state.

Optionally, the frame event parameter includes at least one of the following: an error symbol event parameter, an error frame event parameter, an error frame period event parameter, and an error frame second statistical event parameter.

Optionally, determining, according to the frame event parameter, whether the ring network has signal degradation includes: determining that the ring network occurs when the number of occurrences of the frame event exceeds a preset event threshold in a preset time period. The signal is degraded.

In an example, before the receiving the ring link state monitoring message of the link operation (maintenance), the method further includes: setting at least one ring on the ring network. The network protection instance receives the registration message of each ring network protection instance, and the registration message carries the corresponding ring network protection instance identifier.

Optionally, in the case that the ring network has signal degradation, the corresponding ring switching operation performed by the corresponding ring network node includes: protecting the corresponding ring network in case that the ring network has signal degradation The instance sends a signal degradation indication; according to different ring protection instances, a corresponding protection switching operation is performed.

In an example, in the case that the ring network has signal degradation, after the corresponding ring network node performs the corresponding protection switching operation, the method further includes: continuing to receive the ring network link state monitoring message from the link oam, The ring network link state monitoring message carries a frame event parameter; the ring network nodes determine a ring network signal quality indicator according to the frame event parameter; and when the ring network signal quality indicator is higher than a preset recovery threshold Then, the ring network that performs the protection switching operation is restored to the original ring network.

Optionally, detecting, by the end node of the link, whether the link has signal degradation, respectively: determining whether signal degradation occurs on the link by detecting an attenuation condition of the laser signal.

In another aspect, the present disclosure further provides a protection switching apparatus for a ring network, including: a detecting unit, configured to enable an end node of the link to detect whether a signal degradation occurs on the link, respectively; and a protection switching unit configured to be in the In the case where the link is degraded, the corresponding node performs a corresponding protection switching operation.

Optionally, the detecting unit includes: a receiving module, configured to enable an end node of the link to receive a ring link state monitoring message of the link oam, where the ring link state monitoring message carries a frame event parameter; And being configured to cause the end node to determine whether signal degradation occurs on the link according to the frame event parameter.

Optionally, the apparatus further includes a modifying unit, configured to increase a processing mechanism for signal degradation in the ring network protection state machine and modify the basis based on whether the end node of the link respectively detects whether the link has signal degradation. The request/status bit value of the ring-protected protocol message of the signal failure, so that the ring network protection state machine and the ring network protection protocol message are compatible with the processing of signal degradation.

Optionally, the modifying unit is configured to: add local signal degradation local SD, local signal degradation clear local clear SD, and ring network automatic protection switching based on signal degradation in the ring protection request/state priority list. An APS-SD entry, wherein the R-APS-SD entry is used to notify the neighboring node of the ring network protection protocol packet by using the modified ring network protection protocol packet when the current end node is in the local SD state. The current link of the node is in a signal degradation state, and the corresponding request/status position in the ring protection protocol packet is a signal degradation state.

Optionally, the determining module is configured to determine that the ring network has signal degradation when the number of occurrences of the frame event exceeds a preset event threshold in a preset time.

In an example, the apparatus further includes: a setting unit configured to set at least one ring protection instance on the ring network before receiving a ring link state monitoring message of the link oam; and a registration unit, configured to receive the The registration message of each ring network protection instance set by the setting unit, where the registration message carries the corresponding ring network protection instance identifier.

Optionally, the protection switching unit is configured to: when a signal degradation occurs in the ring network, send a signal degradation indication to the corresponding ring network protection instance; perform corresponding protection switching according to different ring network protection instances. operating.

Optionally, the device further includes a recovery unit, where the receiving module is further configured to: after the ring network performs signal degradation, the corresponding ring network node continues to receive the link after performing the corresponding protection switching operation. The ring network link state monitoring message of the oam, the ring network link state monitoring message carries a frame event parameter; the determining module is further configured to determine a ring network signal quality indicator according to the frame event parameter; the recovery unit And setting, in the case that the ring network signal quality indicator is higher than the preset recovery threshold, restoring the ring network that performs the protection switching operation to the original ring network.

The protection switching method and device for the ring network provided by the embodiment of the present disclosure, the end node of the link can detect whether the link has signal degradation; in the case that the ring network has signal degradation, the corresponding ring network node A corresponding protection switching operation can be performed to communicate and service using well-behaved nodes and links. In this way, the end node of the link can determine the signal quality on the link, whether there is signal degradation such as congestion or error frame, and perform corresponding protection switching operation in the case of signal degradation, thereby effectively improving the ring. Network link performance.

DRAWINGS

FIG. 1 is a flowchart of a protection switching method for a ring network according to an embodiment of the present disclosure;

2 is a schematic structural view of a ring network in an embodiment of the present disclosure;

3 is a schematic structural diagram of nodes in a ring network in an embodiment of the present disclosure;

4 is another schematic structural diagram of an example of ring network protection in an embodiment of the present disclosure;

FIG. 5 is a schematic diagram of protection of a link SD generation notification ring network according to an embodiment of the present disclosure;

FIG. 6 is a schematic diagram of performing protection switching after a ring network protection receiving link SD generates a message according to an embodiment of the present disclosure;

FIG. 7 is a schematic diagram of recovery of a link SD disappearing notification ring network protection according to an embodiment of the present disclosure;

FIG. 8 is a schematic structural diagram of a protection switching device for a ring network according to an embodiment of the present disclosure.

detailed description

The present disclosure will be described in detail below with reference to the accompanying drawings. It is understood that the specific embodiments described herein are merely illustrative of the disclosure and are not intended to be limiting.

As shown in FIG. 1 , an embodiment of the present disclosure provides a protection switching method for a ring network, including:

S11. The end nodes of the link respectively detect whether a signal degradation occurs on the link.

S12. In a case where signal degradation occurs on the link, the corresponding node performs a corresponding protection switching operation.

The protection switching method for the ring network provided by the embodiment of the present disclosure, the end node of the link can detect whether the link has signal degradation; in the case that the ring network has signal degradation, the corresponding ring network node can perform Corresponding protection switching operations to communicate and service using well-behaved nodes and links. In this way, the end node of the link can determine the signal quality on the link, whether there is signal degradation such as congestion or error frame, and perform corresponding protection switching operation in the case of signal degradation, thereby effectively improving the ring. Network link performance.

Optionally, in step S11, it may be detected by multiple methods whether the link has signal degradation, for example, by detecting the attenuation of the laser signal, determining whether the link has signal degradation, or by using a link oam ring. The network link state monitoring message determines whether signal degradation or the like has occurred on the link. The embodiments of the present disclosure do not limit this.

Specifically, in step S11, the end nodes of the link respectively detect whether the link has signal degradation may include:

The end nodes of the link respectively receive a ring link state monitoring message of the link oam, where the ring link state monitoring message carries a frame event parameter;

The end node determines whether the ring network has signal degradation according to the frame event parameter.

In this way, the end nodes of each link can respectively receive the ring network link state monitoring message of the link oam, and determine whether the ring network has signal degradation according to the frame event parameter carried in the ring link state monitoring message; In the event of signal degradation, the corresponding node is able to perform a corresponding protection switching operation to communicate and service using well-signaled nodes and links. In this way, since Link oam can perform link operation, monitoring and fault location in the data link layer, each link end node can determine the signal quality on the ring network according to the frame event parameters provided by link oam, and whether there is congestion, A signal degradation condition such as a wrong frame, and a corresponding protection switching operation in the case where signal degradation occurs.

In a specific implementation, a ring network can have multiple nodes, and each node can monitor the status of the node itself and the link directly connected to the node through link oam. Optionally, in step S11, the frame event parameter carried in the ring network link state monitoring message may include one or more of the following: an error symbol event parameter, an error frame event parameter, an error frame period event parameter, and an error frame second statistic. Event parameters, etc., link end nodes can achieve real-time monitoring of link performance by monitoring these frame event parameters.

Depending on the specific situation and needs, the user can select one of the above frame event parameters to reflect the link performance, and can also use a combination of multiple frame events to reflect the performance of the link. The embodiments of the present disclosure do not limit this.

For example, in one embodiment of the present disclosure, the end node of the link determines how the ring link performance is and whether signal degradation has occurred based on the error frame event parameter. Specifically, when the link oam receives the error frame (RxErroredFrame) for more than the specified error threshold (ErrThreshold) during the Window monitoring period, it determines that an error frame event (ErrFrameEvent) occurs on the link, and marks the Window as an event window. Identifies that an error frame event has occurred. which is:

In the Window monitoring time, if RxErroredFrame≧ErrThreshold,

Then ErrFrameEvent=RxErroredFrame/ErrThreshold.

Optionally, the frame event parameter carried in the message may be monitored according to the status of the ring link state to determine whether the ring network has signal degradation. The specific determination method and standard of whether the signal is degraded or not can be various, and the embodiment of the present disclosure does not limit this. For example, in an embodiment of the present disclosure, if the number of occurrences of the frame event exceeds the preset event threshold in a preset time, it may be determined that the ring network has signal degradation.

In a specific implementation, the cumulative time of the frame event parameter may be configured first, that is, the cumulative number of occurrences of the frame event in the long time range. Optionally, since the link oam performs frame event monitoring in different monitoring windows (Window), the corresponding accumulated time can be configured by configuring the number of windows (N).

Optionally, the preset event threshold EvThresholdMax can also be configured. When the cumulative number of frame events (ie, the ring network performance indicator) ErrPef is greater than the configured preset event threshold EvThresholdMax in the time period of t≦N*Window, it can be determined that the ring network has signal degradation. Still take the error frame event as an example:

ErrPef+=ErrFrameEvent during the time of t≦N*Window;

If ErrPef ≧ EvThresholdMax, the link is considered to have signal degradation.

It should be noted that the foregoing embodiment uses the frame event parameter as an error frame event parameter as an example to describe how to determine whether signal degradation occurs. However, the present disclosure is not limited thereto. Frame event parameters such as error symbol event parameters, error frame period event parameters, error frame seconds statistical event parameters, etc. can also be derived according to a similar principle, and only need to replace the corresponding parameters. For example, in another embodiment of the present disclosure, the RxErroredFrame in this embodiment is replaced with an RxErroredSymbol (representing the number of error symbols received in a certain period), and the corresponding frame event is replaced with an error symbol event. The various thresholds corresponding to different frame events may be adjusted as needed, and may be the same or different from each other. The embodiments of the present disclosure do not limit this.

Correspondingly, for the relationship between the number of occurrences of the frame event and the preset event threshold, the statistics may be separately performed according to different event types, or different types of frame events may be combined according to certain rules, for example, different types of frames are to be combined. The event is written as a logical relationship and is counted according to the logical relationship. For example, in one embodiment of the present disclosure, the ring network is most sensitive to the error frame period event ErrFramePeriodEvent, and sensitive to the error frame second accumulation event ErrFrameSecsSummaryEvent, then a logical relationship can be constructed:

ErrPef+=3ErrFramePeriodEvent+ErrFrameSecsSummaryEvent

In this way, when the ErrFrameSecsSummaryEvent occurs more frequently, the ErrPef grows faster. Once the threshold is exceeded, the loop can be protected in time.

It should be noted that, since the ring network protection also performs switching or recovery according to the generation or disappearance of the link SF, the SF (Signal Failure) or SD (Signal Degradation) ring network is required to perform switching, SF and The ring network can perform recovery when the SD disappears. The SD processing mechanism does not exist in the original ring state machine. The embodiment of the present disclosure needs to modify the ring network protection state machine to the SD processing mechanism.

Specifically, in an embodiment of the present disclosure, before the end nodes of the link respectively detect whether the link has signal degradation, the method further includes: adding a pair in the ring network protection state machine based on the signal failure. The signal degradation processing mechanism and the request/status bit value of the ring network protection protocol message based on the signal failure are modified to make the ring network protection state machine and the ring network protection protocol message compatible with the signal degradation processing.

In a specific implementation, the local signal degradation local SD, the local signal degradation clear local clear SD, and the ring network automatic protection switching R-APS-SD item based on signal degradation may be added in the ring protection request/state priority list; The R-APS-SD entry is used to notify the neighboring node that the current link is in signal degradation by using the modified ring network protection protocol packet when the current end node is in the local SD state. a state, wherein a corresponding request/status location in the ring protection protocol packet is a signal degradation state.

Optionally, the modified ring protection request/status priority may be as shown in Table 1.

Table 1

Modify the ring protection protocol packet request/status bit value as shown in Table 2. When the current end node is in the local SD state, the current end node sends the ring network protection protocol to the neighboring node by using the corresponding request/status position in the ring network protection protocol packet in Table 2 as the signal degradation state (ie, 1010). A message notifying the neighboring node that the current link is in a signal degradation state.

Table 2

Specifically, after the signal is degraded, the corresponding node may perform a specific protection switching operation, and the block at both ends of the link where the signal is degraded, and the R_SF message is concurrently sent to notify other nodes that the protection link has a problem and needs to perform protection switching. The RPL master node and the RPL pro node can change both ends of the RPL link into a forward state, changing the transmission path of the link signal.

The above embodiment illustrates the overall situation in which the protection switching is performed after the signal degradation of the ring network occurs. Further, in the physical architecture of the same ring network, multiple logically different ring network instances can be supported, and corresponding services can be implemented on the corresponding ring network instance. As shown in FIG. 2, in an embodiment of the present disclosure, in a ring network composed of four nodes A, B, C, and D, a ring network instance is established, where A is a master node and D is a neighbor node. . The link between ADs is an RPL backup link. There are two services traffic1 and traffic2 in the ring network instance. In other embodiments of the present disclosure, other ring network instances may also be established in the ring network, with other master nodes and corresponding alternate links, and embodiments of the present disclosure are not limited thereto.

For the case of establishing a ring network protection instance on the ring network, before the end node of the link receives the ring network link state monitoring message of the link oam, the protection switching method for the ring network provided by the embodiment of the disclosure may further include:

Setting at least one ring network protection instance on the ring network;

Receiving a registration message of each ring network protection instance, where the registration message carries a corresponding ring network protection instance identifier.

Optionally, the registration message of the ring protection instance may include the content as shown in Table 3.

table 3

Msg-type(1byte)Msg-type(1byte)	value(1byte)Value(1byte)
SD-process(module id＝15)SD-process(module id=15)	Erps-id(1～32)Erps-id (1~32)

As shown in Table 3, the first behavior item name and the second behavior corresponding value. The SD-process (module id=15) is the module number of the signal degradation detection process. The Erps-id (1 to 32) is the ring network protection instance number. The ring network protection instance number 1 to 32 is notified to the signal degradation detection process module number. 15 signal detection module.

Based on this, in step S13, in the case that the ring network has a signal degradation, the corresponding node performing the corresponding protection switching operation may specifically include:

Transmitting a signal degradation indication to the corresponding ring network protection instance if the ring network has signal degradation;

Perform corresponding protection switching operations based on different ring protection instances.

Optionally, the signal degradation indication sent to the corresponding ring protection instance may include content as shown in Table 4, which is used to indicate which ring instance has signal degradation. For example, if three different ring protection instances A1, A2, and A3 are set on a physical ring network, and the ring protection instances corresponding to A1 and A3 are degraded, they can be protected to the ring network instances A1 and A3 respectively. The signal degradation indication is sent, and the indication carries the ring protection instance number and the signal degradation indicator character (SD-state). Correspondingly, after receiving the signal degradation indications, the ring protection instances A1 and A3 can respectively block the two ends of the link where the signal is degraded, and the RPL primary node and the RPL pro node can change the two ends of the RPL link into a forward state. Change the transmission path of the link signal.

Table 4

Msg-type(1byte)Msg-type(1byte)	Erps-id(1byte)Erps-id(1byte)	SD-state(1byte)SD-state (1byte)
erps(module id＝12)Erps(module id=12)	1～321 to 32	1(SD)/0(SD clear)1(SD)/0(SD clear)

As shown in Table 4, the first behavior item name and the second behavior corresponding value. Erps (module id=12) is the ring protection module number, 1 to 32 is the ring protection instance number, and 1 (SD)/0 (SD clear) indicates whether signal degradation has occurred.

Further, in the case that the ring network has a signal degradation, the protection switching method for the ring network provided by the embodiment of the present disclosure further includes:

And continuing to receive a ring link status monitoring message from the link oam, where the ring link status monitoring message carries a frame event parameter;

The link end nodes determine a ring network signal quality indicator according to the frame event parameter;

When the signal quality indicator of the ring network is higher than the preset recovery threshold, the ring network that performs the protection switching operation is restored to the original ring network.

That is to say, for a ring network that has undergone protection switching, the trusted link may be a standby link or an original link. When the link that the trusted link is the original link, the signal quality on the original link can be continuously monitored. After the signal quality on the original link is restored, the ring network that performs the protection switching operation can be restored to the original ring network. Continue to use the original ring network.

Further, in the foregoing embodiment, after the protection switching or the switching recovery is performed on the ring network, the link that the SD generates or disappears may also be reported in the foregoing network, so as to comprehensively analyze and improve the overall situation of the link node and the link.

The protection switching method for the ring network provided by the present disclosure will be described in detail below through specific embodiments.

For the convenience of description, the nodes on which the protection switching method for the ring network provided by the present embodiment is based are briefly described. The node of the carrier-grade Ethernet service in this embodiment may include:

A.linkoam link monitoring unit

B. Ring network protection switching unit

C. Link performance calculation and alarm processing unit

The link performance calculation and alarm processing unit may obtain the link state information data from the linkoam link monitoring unit, and determine whether to notify the ring network protection switching unit of the message that the SD is generated or disappeared after the calculation, and then the ring network protection switching unit Perform protection switching.

The relationship between the three units: the link performance calculation and alarm processing unit and the linkoam link monitoring unit are in a one-to-one relationship. Since one or more ring protection instances can be configured on a single ring network node, and the link performance calculation and alarm processing unit requirements notify the current link SD status of the ring network instance, the link performance calculation needs to be advertised when creating the ring network instance. And the alarm processing unit "ring network instance number". The relationship between the three units corresponding to one or more ring network instances is shown in Figures 3(a) and 3(b).

Embodiment 1: SD generation trigger ring network protection switching

In this embodiment, an example of configuring a ring network protection is taken as an example, and only the generation and disappearance of the link SD are concerned. Since the generation and disappearance of SF is not the focus of this disclosure, no link is generated for all links of the default protection group.

Step S21: Create an Ethernet ring network protection group, and add the protection service to the protection group.

In the specific implementation, the four nodes in the ring topology create an Ethernet ring protection group. Configure the RPL (ring protection link) link and the RPL master node A and the RPL neighbor node D. The RPL is in the block state to prevent the network from being looped. Add the two services to be protected to the ring protection group. After the ring network is started, the master node A notifies other nodes that the RPL is blocked by sending an R_NR_RB message, and all nodes enter an idle state. The service is transmitted as shown in Figure 2. For example, the transmission path of traffic 2 is A-B-C-D.

Step S22: After the ring network protection group is created, the linkoam protocol is automatically run on the two ports of the four protection group nodes to monitor the performance of the working link, as shown in FIG. 4 .

In a specific implementation, the link event includes an error symbol event, an error frame event, an error frame period event, and an error frame second accumulation event, which can achieve the purpose of monitoring link performance in real time. Customers can choose one of them or use a variety of event combinations to reflect the performance parameters of the link based on actual conditions.

Take the error frame event as an example:

If the number of received error frames (RxErroredFrame) exceeds the specified performance threshold (Threshold) during the Window monitoring period, the link is considered to have an error frame event (ErrFrameEvent). which is:

During Window monitoring time, RxErroredFrame≧Threshold,

Then ErrFrameEvent=RxErroredFrame/Threshold.

Step S23: The link performance calculation and the alarm processing unit are started, and the number of error frame events in the link is recorded. If the performance of the link AB is detected to be lower than the set performance standard, the link AB is considered to have an SD, and the ring network protection is notified. group. As shown in Figure 5.

In a specific implementation, the startup link performance calculation and alarm processing unit needs to configure the number of window monitoring periods (N) and the event occurrence performance threshold PefThresholdMax.

Take the error frame event as an example:

When t≦N*Window time,

ErrPef+=ErrFrameEvent;

If ErrPef≧PefThresholdMax, the link is considered to have SD.

Step S24: After receiving the SD message, the ring network protection group nodes A and B perform corresponding protection switching. The block at both ends of the link of the SD will be sent, and the R_SF message will be sent to notify other nodes. If there is a problem with the protection link, protection switching needs to be performed. The RPL master node A and the RPL pro node D will change both ends of the RPL link into a forward state. After the protection switching is performed, the service is transmitted as shown in Figure 6. For example, the transmission path of traffic 2 is A-D.

Embodiment 2: SD disappears trigger ring network protection switching recovery

In this embodiment, a ring network protection instance is configured, and only the generation and disappearance of the link SD are concerned. Because the generation and disappearance of SF is not the focus of this article, no link is generated for all links in the default protection group.

Step S31: Create an Ethernet ring network protection group. Because the link A-B generates SD, it is in the protection switching state.

In the specific implementation, the block at both ends of the link of the SD will be sent, and the R_SF message will be sent to notify other nodes. If there is a problem with the protection link, protection switching needs to be performed. The RPL master node and the RPL pro node will change both ends of the RPL link into a forward state. After the protection switching is performed, the service is transmitted as shown in Figure 6 (5). For example, the transmission path of traffic 2 is A-D.

Step S32: After the ring network protection group is created, the linkoam protocol is automatically run on the east and west ports of the four protection group nodes to monitor the performance of the working link.

Take the error frame event as an example:

During Window monitoring time, RxErroredFrame≧Threshold,

Then ErrFrameEvent=RxErroredFrame/Threshold.

In step S33, the link performance calculation and the alarm processing unit are started, and the number of error frame events on the link is recorded. If the performance of the link is detected to be lower than the set performance standard, the link SD is considered to be lost, and the ring network protection group is notified. . As shown in Figure 7.

In a specific implementation, the startup link performance calculation and alarm processing unit needs to configure the number of window monitoring periods (N) and the event occurrence performance threshold ThresholdMin.

When t≧N*Window time,

ErrPef+=ErrFrameEvent;

If ErrPefPef≦ThresholdMin, the link SD is considered to have disappeared.

Step S34: After receiving the message that the SD disappears, the ring network protection group nodes A and B perform corresponding switching recovery. The RPL master node A starts the WTR (wait to restore) timer. After the WTR times out, the RPL port block is sent, the R_NR_RB message is sent, and the SD disappears port forward. After the RPL Pro Node D receives the R_NR_RB message, it will block the RPL port. After the Node B receives the R_NR_RB message, the SD disappears the port forward. After the switchover recovery is performed, the service is transmitted as shown in Figure 7.

The linkoam link performance monitoring unit includes a data acquisition module, a data calculation module, and a judgment module, wherein: the data acquisition module is configured to obtain performance data of a link in the protection link; and the data calculation module is configured to be based on the link. The performance data is used to calculate the performance of the working link; the judging module is used to judge whether the performance of the link is generated or disappeared.

The performance of the link is measured by the error symbol event as an example, and the protection switching and its recovery are described in detail.

Setting: ErrSymbolWindow=60(s),

ErrSymbolThreshold=1000, PefThresholdMax=8, PefThresholdMin=2, N=10;

Performance data collection: RxErroredSymbol;

Performance data calculation: if RxErroredSymbol≧ErrSymbolThreshold;

ErrSymbolEvent=RxErroredSymbol/ErrSymbolThreshold;

ErrPef+=ErrSymbolEvent;

Window=N*ErrSymbolWindow.

Judging performance indicators: In the Window, if ErrPef≧PefThresholdMax, it indicates that the SD is generated, notifies the ring network protection node, and performs protection switching. When the window is exceeded, if ErrPeft≦PefThresholdMin, the link SD disappears, and the ring network protection node is notified to perform the switchover recovery.

The above embodiment uses the frame event parameter as an error frame event parameter and an error symbol event parameter as an example to describe how to determine whether signal degradation occurs or whether signal degradation disappears. However, the present disclosure is not limited thereto. Frame event parameters such as error frame period event parameters and error frame seconds statistical event parameters can also be obtained according to a similar principle, and only need to replace the corresponding parameters. The various thresholds corresponding to different frame events may be adjusted as needed, and may be the same or different from each other. The embodiments of the present disclosure do not limit this.

Correspondingly, as shown in FIG. 8 , an embodiment of the present disclosure further provides a protection switching apparatus for a ring network, including:

The detecting unit 81 detects, by the end node of the link, whether the link has signal degradation, respectively;

The protection switching unit 82 is configured to perform a corresponding protection switching operation in the case that signal degradation occurs on the link.

The protection switching device for the ring network provided by the embodiment of the present disclosure, the end node of the link can detect whether the link has signal degradation; in the case that the ring network has signal degradation, the corresponding ring network node can perform corresponding Protection switching operations to communicate and service using well-behaved nodes and links. In this way, because the end node of the link can determine the signal quality on the link, whether there is signal degradation such as congestion or frame error, and corresponding protection switching operation occurs in the case of signal degradation, thereby effectively improving the signal. Ring link performance.

Optionally, the detecting unit includes:

The receiving module, the end node for the link respectively receives the ring network link state monitoring message of the link oam, where the ring network link state monitoring message carries the frame event parameter;

And a determining module, configured to determine, by the end node, whether the link has signal degradation according to the frame event parameter.

In this way, because Link oam can perform link operation, monitoring and fault location in the data link layer, each ring network node can determine the signal quality on the ring network according to the frame event parameters provided by link oam, and whether there is congestion or error. A signal such as a frame is degraded, and a corresponding protection switching operation is performed in the case where signal degradation occurs.

Optionally, the device further includes a modifying unit, configured to increase processing of signal degradation in a ring network protection state machine based on signal failure before the end nodes of the link respectively detect whether the link has signal degradation The mechanism further modifies the request/status bit value of the ring network protection protocol message based on the signal failure, so that the ring network protection state machine and the ring network protection protocol message are compatible with the signal degradation processing.

Optionally, the modifying unit may be configured to add a local signal degradation local SD, a local signal degradation clear local clear SD, and a signal degradation based loop automatic protection switching R- in the ring protection request/state priority list. An APS-SD entry, wherein the R-APS-SD-term is used to notify the current end node of the ring network protection protocol packet after the current end node is in the local SD state. The current link of the neighboring node is in a signal degradation state, and the corresponding request/status position in the ring protection protocol packet is a signal degradation state.

Optionally, the determining module is configured to determine that the ring network has signal degradation when the number of occurrences of the error frame event exceeds a preset event threshold.

Further, the protection switching apparatus for the ring network provided by the embodiment of the present disclosure may further include:

a setting unit, configured to set at least one ring protection instance on the ring network before receiving a ring link state monitoring message of the link oam;

And a registration unit, configured to receive a registration message of each ring network protection instance set by the setting unit, where the registration message carries a corresponding ring network protection instance identifier.

Optionally, the protection switching unit 82 is configured to: send a signal degradation indication to the corresponding ring network protection instance if the ring network has signal degradation; perform a corresponding protection switching operation according to different ring network protection instances. .

Further, the protection switching apparatus for the ring network provided by the embodiment of the present disclosure may further include a recovery unit, and the receiving module may be further configured to perform corresponding protection on the ring network node if the ring network has signal degradation. After the switching operation, continuing to receive the ring network link state monitoring message from the link oam, where the ring link state monitoring message carries the frame event parameter;

The determining module is further configured to determine a ring network signal quality indicator according to the frame event parameter;

The recovery unit may be configured to restore the ring network that performs the protection switching operation to the original ring network if the ring network signal quality indicator is higher than the preset recovery threshold.

Optionally, the detecting unit 81 is configured to determine whether signal degradation occurs in the link by detecting an attenuation condition of the laser signal.

It is to be understood that the term "comprises", "comprising", or any other variants thereof, is intended to encompass a non-exclusive inclusion, such that a process, method, article, or device comprising a series of elements includes those elements. It also includes other elements that are not explicitly listed, or elements that are inherent to such a process, method, article, or device. An element that is defined by the phrase "comprising a ..." does not exclude the presence of additional equivalent elements in the process, method, item, or device that comprises the element.

Through the description of the above embodiments, those skilled in the art can clearly understand that the foregoing embodiment method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be through hardware, but in many cases, the former is better. Implementation. Based on such understanding, portions of the technical solutions of the present disclosure that contribute substantially or to the prior art may be embodied in the form of a software product stored in a storage medium (eg, ROM/RAM, disk, The optical disc includes a number of instructions for causing a terminal device (which may be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to perform the methods described in various embodiments of the present disclosure.

The above is only a preferred embodiment of the present disclosure, and is not intended to limit the scope of the patents of the present disclosure, and the equivalent structure or equivalent process transformations made by the present disclosure and the contents of the drawings may be directly or indirectly applied to other related technical fields. The same is included in the scope of patent protection of the present disclosure.

Industrial applicability

The present disclosure is applicable to the field of communication technologies, and the end node of the link is used to determine the signal quality on the link, whether there is signal degradation such as congestion or frame error, and the corresponding protection switching occurs in the case of signal degradation. Operation, which effectively improves the performance of the ring link.

Claims

A protection switching method for a ring network, comprising:

The end nodes of the link respectively detect whether the link has signal degradation;

In the case where signal degradation occurs on the link, the corresponding node performs a corresponding protection switching operation.
The method according to claim 1, wherein the end nodes of the link respectively detect whether the link has signal degradation includes:

The end nodes of the link respectively receive a ring link state monitoring message of the link oam, where the ring link state monitoring message carries a frame event parameter;

The end node determines, according to the frame event parameter, whether signal degradation occurs on the link.
The method of claim 2, wherein before the end nodes of the link respectively detect whether a link has undergone signal degradation, the method further comprises:

Adding a processing mechanism for signal degradation and modifying a request/status bit value of the ring network protection protocol message based on the signal failure in the ring network protection state machine based on the signal failure, so that the ring network protection state machine and the ring The network protection protocol message is compatible with the processing of signal degradation.
The method according to claim 3, wherein the processing mechanism for adding signal degradation and modifying the request/status bit value of the ring failure protection protocol message based on the signal failure in the ring failure protection state machine based on the signal failure comprises:

Adding a local signal degradation local SD, a local signal degradation clearing local clear SD, and a signal degradation based loop automatic protection switching R-APS-SD entry in the ring protection request/state priority list; wherein the R- The APS-SD entry is used to notify the neighboring node that the current link is in a signal degradation state by using the modified ring network protection protocol packet when the current end node is in the local SD state. The corresponding request/status position in the ring network protection protocol packet is a signal degradation state.
The method of claim 2, wherein the frame event parameter comprises at least one of the following:

Error symbol event parameter, error frame event parameter, error frame period event parameter, error frame second statistical event parameter.
The method according to claim 2, wherein the determining, according to the frame event parameter, whether the ring network has undergone signal degradation comprises:

If the number of occurrences of the frame event exceeds the preset event threshold in the preset time, it is determined that the ring network has signal degradation.
The method of claim 2, wherein before the receiving the ring link state monitoring message of the link oam, the method further comprises:

Setting at least one ring network protection instance on the ring network;

Receiving a registration message of each ring network protection instance, where the registration message carries a corresponding ring network protection instance identifier.
The method according to claim 7, wherein in the case that the ring network has signal degradation, the corresponding node performs a corresponding protection switching operation including:

Transmitting a signal degradation indication to the corresponding ring network protection instance if the ring network has signal degradation;

Perform corresponding protection switching operations based on different ring protection instances.
The method according to any one of claims 2 to 8, wherein, in the case that a signal degradation occurs in the ring network, after the corresponding node performs a corresponding protection switching operation, the method further includes:

And continuing to receive a ring link status monitoring message from the link oam, where the ring link status monitoring message carries a frame event parameter;

The link end node determines a ring network signal quality indicator according to the frame event parameter;

When the signal quality indicator of the ring network is higher than the preset recovery threshold, the ring network that performs the protection switching operation is restored to the original ring network.
The method of claim 1, wherein detecting, by the end node of the link, whether the link has signal degradation, respectively comprises determining whether signal degradation occurs in the link by detecting a decay condition of the laser signal.
A protection switching device for a ring network, comprising:

a detecting unit, configured to enable an end node of the link to detect whether a signal degradation occurs on the link, respectively;

The protection switching unit is configured to cause the corresponding node to perform a corresponding protection switching operation in the event that signal degradation occurs on the link.
The apparatus according to claim 11, wherein said detecting unit comprises:

The receiving module is configured to enable the end nodes of the link to receive the ring link state monitoring message of the link oam, where the ring link state monitoring message carries the frame event parameter;

And a determining module, configured to enable the end node to determine whether signal degradation occurs on the link according to the frame event parameter.
The apparatus according to claim 12, further comprising a modifying unit configured to add a pair in the ring-based protection state machine based on the signal failure before the end nodes of the link respectively detect whether the link has signal degradation The signal degradation processing mechanism and the request/status bit value of the ring network protection protocol message based on the signal failure are modified to make the ring network protection state machine and the ring network protection protocol message compatible with the signal degradation processing.
The apparatus according to claim 13, wherein said modifying unit is arranged to add local signal degradation local SD, local signal degradation clear local clear SD, signal degradation based in said ring protection request/state priority list The ring network automatically protects the R-APS-SD entry; wherein the R-APS-SD entry is used to: when the current end node is in the local SD state, the current end node passes the modified ring The network protection protocol message notifies the neighboring node that the current link is in a signal degradation state, and the corresponding request/status position in the ring protection protocol packet is a signal degradation state.
The apparatus of claim 12, further comprising:

a setting unit, configured to set at least one ring protection instance on the ring network before receiving a ring link state monitoring message of the link oam;

The registration unit is configured to receive a registration message of each ring network protection instance set by the setting unit, where the registration message carries a corresponding ring protection instance identifier.
A computer readable storage medium storing computer executable instructions that, when executed, implement the protection switching method for a ring network according to any one of claims 1-10.