WO2010037305A1

WO2010037305A1 - Method, node device and ring network for notifying re-routing

Info

Publication number: WO2010037305A1
Application number: PCT/CN2009/073830
Authority: WO
Inventors: 王彧; 杨榆; 饶宝全; 任彦琦; 谭文剑; 黄蕾
Original assignee: 华为技术有限公司
Priority date: 2008-09-28
Filing date: 2009-09-09
Publication date: 2010-04-08
Also published as: CN101686419A

Abstract

A method, node device and ring network for notifying re-routing are provided in the present invention. The method for notifying re-routing includes that: the boundary node of the optical channel data unit receives the ODUk ring channel alarm, and judges whether the interruption occurs in the service of the ODUk ring in accordance with the ODUk ring channel alarm; if the result of the judgment is yes, the boundary node on the ODUk ring notifies the opposite node of the boundary node to trigger re-routing when the service is interrupted because of the fault in the ring. The node device includes the function modules for performing the above method. The ring network includes the boundary node on the ODUk ring and the opposite node of the boundary node. In the embodiment of the present invention, after judging the interruption occurs in the service of the ODUk ring, the boundary node notifies its opposite node to trigger re-routing when the service is interrupted because of the fault in the ring, which can ensure that the opposite node performs re-routing only when the service is interrupted because of the fault in the ODUk ring, so as to reduce the processing load to the node, save the time required by service recovery and improve the re-routing efficiency.

Description

Method for notifying rerouting, node device and ring network

This application claims priority to Chinese Patent Application No. 200810223804.2, entitled "Method for Notifying Rerouting, Node Equipment and Ring Network", filed on September 28, 2008, the entire contents of which are incorporated by reference. In this application. Technical field

The present invention relates to a Wavelength Division Multiplexing (WDM) network technology, and in particular, to a method, a node device, and a ring network for notification rerouting. Background technique

In a WDM network, if a link interruption occurs, more services are interrupted, resulting in a large amount of data loss, resulting in significant losses. For this reason, the optical channel transport unit (ODUk) ring protection of the 0DU1 or 0DU2 level is created in the WDM network. When the working channel is interrupted, the service is switched to the protection channel to enable the service. Ability to recover quickly. The ODUk ring protection is a channel-level protection mode. The channel-level protection mode in this WDM network is the multiplex section protection applied in the Synchronous Digital Hierarchy (SDH) network (Multiplexer Section Protection, below). The model for abbreviations: MSP) is similar.

In the process of configuring the ODUk ring, the protection group of the ODUk ring is configured first. Figure 1 is a schematic diagram of the structure of the ODUk ring protection service of the prior art. As shown in Figure 1, the ring nodes A, B, and C of the protection group of the ODUk ring are shown in Figure 1. , D, E, F, there are two links between each two ring nodes, which are the opposite working link 1 and the standby link 2. When the working link 1 is interrupted, the service is switched from the working channel to On the protection channel, the ODUk ring can only be switched on the ingress or outbound nodes. The other ring nodes cannot be switched. If the working link 1 between node A and node B is interrupted in Figure 1, the service segment cannot be transmitted on the working channel A→B→C, and the channel switching will be performed at the ringing node A and the outgoing node C. The service segment will take the protection channel A→F→E→D→C, and the service of the service segment will not be affected. Automat ica l ly Swi tched Opt ica l Network (hereinafter referred to as ASON) is a new generation optical transport network based on WDM network combined with automatic control technology, which can automatically complete the network exchange connection function automatically. That is, on the basis of automatic discovery of network resources and topology resource structures, an end-to-end automatic connection is established through signaling processing and interaction.

AS0N has automatic discovery, automatic service establishment, and business recovery. The automatic discovery function uses a Link Management Protocol (LMP) to discover and verify links between two network devices, and uses a routing protocol to flood the discovered links throughout the network. Each device in the network can learn the network topology information. The automatic service establishment function utilizes the automatic control technology. The user only needs to select the source node and the destination node related information of the service, and can automatically establish a service, and the route of the service is the most Excellent; The service recovery function is to automatically detect the failure of the service when the service is interrupted, and automatically establish a new path to recover the interrupted service.

The AS0N control plane sends an ODUk ring channel alarm and the network topology information is updated when the network is faulty, such as a link failure or a node failure. Therefore, in the prior art, the AS0N network determines whether the service is based on the network topology information. Was interrupted. If the service is interrupted, the control plane can dynamically reroute according to the network topology information, that is, the routing algorithm is based on the network topology information, establishing a new optical connection and restoring the service.

In the process of implementing the present invention, the inventor has found that at least the following defects exist in the prior art: Since the link resource needs to update the network topology information, that is, the information of the network map, the information of the updated network map must rely on the control channel. The routing protocol floods the information. The flooding efficiency of the routing information is much lower than that of the channel alarm. Therefore, the efficiency of the ODUk ring failure and rerouting is relatively low, resulting in a long service recovery time. Summary of the invention

The embodiment of the present invention provides a method for notifying a rerouting, a node device, and a ring network, so as to quickly and accurately determine the fault of the ODUk ring when the service is interrupted due to a fault in the ODUk ring. Sending routing problems.

The embodiment of the invention provides a method for notifying rerouting, including:

The edge node of the optical channel data unit ring receives the ODUk ring channel alarm, and determines whether the service of the ODUk ring is interrupted according to the ODUk ring channel alarm;

If the result of the determination is yes, the border node of the ODUk ring notifies the opposite node of the border node to trigger re-routing when the service is interrupted due to an intra-ring failure.

The embodiment of the invention further provides a node device, including:

a receiving module, configured to receive an ODUk ring channel alarm;

a determining module, configured to determine, according to the ODUk ring channel alarm, whether the service of the ODUk ring is interrupted;

The notification module is configured to: when the service of the ODUk ring is interrupted, notify the peer node of the local node to trigger re-routing when the service is interrupted due to an intra-ring failure.

The embodiment of the present invention further provides a ring network, including a border node of the ODUk ring and a peer node of the border node, where the border node of the ODUk ring is configured to receive an ODUk ring channel alarm, according to the ODUk ring. The channel alarm determines whether the service of the ODUk ring is interrupted; if the service of the ODUk ring is interrupted, the peer node is notified to trigger rerouting if the service is interrupted due to an intra-ring failure; the peer node After receiving the notification, if the service is interrupted due to a fault in the ring, rerouting is triggered.

In the foregoing technical solution, after the border node of the ODUk ring determines that the service of the ODUk ring is interrupted, the peer node is notified to trigger the re-routing when the service is interrupted due to the fault in the ring, which can ensure that the peer node only fails in the ODUk ring. Rerouting in case of service interruption, to reduce the processing load of the node, save the time required for service recovery, and improve the rerouting efficiency. DRAWINGS

1 is a schematic structural diagram of a prior art ODUk ring protection service;

2 is a flowchart of Embodiment 1 of a method for notifying rerouting according to the present invention; 3 is a flowchart of Embodiment 2 of a method for notifying rerouting according to the present invention;

4 is a schematic diagram of a network structure applied to an embodiment of a method for notifying rerouting according to the present invention; FIG. 5 is a flowchart of Embodiment 3 of a method for notifying rerouting according to the present invention;

FIG. 6 is a schematic structural diagram of an embodiment of a node device for notifying rerouting according to the present invention. detailed description

The technical solution of the present invention will be further described in detail below through the accompanying drawings and embodiments. 2 is a flowchart of Embodiment 1 of a method for notifying rerouting according to the present invention. As shown in FIG. 2, the method for rerouting may include:

Step 201: The border node of the ODUk ring receives the ODUk ring channel alarm, and determines whether the service of the ODUk ring is interrupted according to the ODUk ring channel alarm.

When the link of the ODUk ring is interrupted, the ODUk ring channel alarm is generated. The border node of the ODUk ring determines whether the service of the ODUk ring is interrupted according to the ODUk ring channel alarm. The boundary node of the ODUk ring may be the outgoing node of the ODUk ring, or It is the entry node of the ODUk ring.

In the case that an ODUk ring channel alarm occurs on the working channel, the border node of the ODUk ring determines whether the service is interrupted, including the following:

In one case, the border node of the ODUk ring receives the ODUk ring channel alarm sent by the link on the working channel, and then switches the service to the protection channel. After a predetermined time, it receives the ODUk sent by the link on the protection channel. If the ring channel alarms, the service interruption of the ODUk ring is determined. In the actual application, the link on the working channel is interrupted, and the ODUk ring channel alarm is issued. At this time, the service on the working channel cannot be transmitted. The border node of the ODUk ring switches the service to the protection channel through the channel switching to continue the transmission. The transfer can be resumed on the protection channel within 500ms. If the link of the protection channel is also interrupted and an ODUk ring channel alarm is issued, the service cannot be transmitted on the protection channel, and the service is interrupted for more than a predetermined time. Since the service may be unstable within a certain period of time when the service is switched from the working channel to the protection channel, first set a predetermined time. If the link on the protection channel issues an ODUk ring channel alarm within the predetermined time, it may be It is caused by instability at the time of switching, At this point, it is considered that the service can be transmitted on the protection channel. If the ODUk ring channel alarm occurs on the link on the protection channel after a predetermined time, the service is interrupted. For example, if the predetermined time is set to 600ms, the link on the protection channel sends an ODUk ring channel alarm within 600ms after the link on the working channel is interrupted and the ODUk ring channel alarm is issued. This may be caused by the instability when the switching occurs. At this time, it is considered that the service can be transmitted on the protection channel; if the ODUk ring channel alarm occurs on the link on the protection channel after 600ms, the service is interrupted.

In another case, the border node of the ODUk ring receives the ODUk ring channel alarm sent by the link on the working channel. If the service cannot be successfully switched to the protection channel, the service interruption of the ODUk ring is determined.

Step 202: If the border node of the ODUk ring determines that the service of the ODUk ring is interrupted, the border node notifies the peer node of the border node to trigger a heavy path when the service is interrupted due to a fault in the ring.

After the border node of the ODUk ring determines that the service of the ODUk is interrupted, it notifies its peer node whether it receives an outbound alarm. If no outbound alarm is received, the service is interrupted due to a fault in the ring, and the peer node triggers rerouting.

When the border node of the ODUk ring determines that the ODUk ring service is not interrupted, no operation can be performed.

For the network that transmits the service, the node is divided into the source node, the destination node, and the boundary node of the ODUk ring. The source node of the service refers to the boundary node where the service enters the network, and the destination node of the service refers to the boundary of the service leaving the network. A node, an edge node of an ODUk ring may be an ingress node or an outbound node, and an ingress ring node refers to the first node through which the service enters the ODUk ring, and the outbound ring node refers to the last node through which the service leaves the ODUk ring.

In this embodiment, when the boundary node of the ODUk ring of the service interruption is the ring-entry node of the ODUk ring according to the ODUk ring channel alarm, the peer node of the ring-entry node is the ring-out node of the ODUk ring; When the boundary node of the ODUk ring of the service interruption is the outbound node of the ODUk ring, the peer node of the outbound node is the ringing node of the ODUk ring. In the case of the network in which the ODUk ring is interrupted, the border node determines that the service of the ODUk ring is interrupted, and then informs the peer node that the re-routing is triggered when the service is interrupted due to the fault in the ring. The node reroutes only when the fault occurs in the ODUk ring, causing the service to be interrupted, which reduces the processing load of the node, saves the time required for service recovery, and improves the rerouting efficiency.

3 is a flowchart of Embodiment 2 of the method for informing re-routing according to the present invention. In this embodiment, when the node that is interrupted by the ODUk ring channel alarm is determined to be the egress ring node of the ODUk ring, the opposite end of the egress ring node The node is the ingress node of the ODUk ring. As shown in Figure 3, the rerouting method includes: Step 301: When the link is interrupted, the link sends an ODUk ring channel alarm, and the ODUk ring outbound node receives the ODUk ring channel alarm.

Step 302: According to the ODUk ring channel alarm, the looping node determines whether the service of the ODUk ring is interrupted.

If the looping node determines that the service is not interrupted, no operation may be performed;

Step 303: If it is determined that the service is interrupted, the looping node notifies the peer node of the border node that the ringing node of the ODUk ring triggers rerouting when the service is not interrupted due to an out-of-loop fault;

Since both the outgoing node and the incoming node are opposite, there may be multiple ODUk rings in one network. The ringing node of an ODUk ring may be the incoming node or the outbound link of the adjacent ODUk ring outside the ODUk ring. point. In the case of a service interruption, the outbound node of the ODUk ring needs to notify the peer node of the ODUk ring, that is, the ringing node of the ODUk ring, to determine whether an outbound alarm is received.

Step 304: The ringing node determines whether the service is interrupted by the out-of-loop fault by determining whether the ring-out alarm is received. If the ring-entry node does not receive the ring-out alarm, it indicates that the ring-in node and the ring-out node are co-located. The fault in the ODUk ring causes service interruption, and the ring-in node triggers re-routing.

The out-of-loop alarm is the ODUk ring channel alarm sent by the link other than the ODUk ring where the ring-in node and the ring-out node are located together. If the ring-entry node receives the ring-out alarm, it cannot be determined that the service is caused by the fault in the ODUk ring. Interrupted, so the ingress node does not trigger rerouting. If the ringing node does not receive the outbound alarm, it can be determined that the service is interrupted by the fault in the ODUk ring, and the ringing node triggers the rerouting.

When rerouting, the source node selects an available link to recover the service. In this embodiment, the service of the ODUk ring of the ODUk ring is interrupted. If the peer node of the egress ring node does not receive the ring-out alarm, the ODUk ring fault can be quickly determined and the re-routing is triggered. The ring-entry node of the ODUk ring reroutes only when the fault occurs in the ODUk ring, which reduces the processing load of the node, saves the time required for service recovery, and improves the efficiency of re-routing.

4 is a schematic diagram of a network structure applied to an embodiment of a method for notifying rerouting according to the present invention. As shown in FIG. 4, in a network for transmitting a service, including: an optical fiber, a node, and the like, the service starts from the user R1 and reaches the user R2, where the node 01 and node 03 are the source node and the destination node of the service in the network respectively; the service can start from the user R1, pass the ODUk ring where the node 01, the node 04 and the node 02 are located, and then reach the user R2 through the node 03, then the node 01 For the service at the ring-entry node of the ODUk ring, node 02 is the outgoing node of the service in the ODUk ring; for the same reason, the service can start from the user R1, pass through the node 01, and then pass through the node 02, the node 04, and the node 03. The ODUk ring reaches the user R2, and the node 02 is the ringing node of the ODUk ring where the service is located at the node 02, the node 04, and the node 03, and the node 03 is the outgoing node of the service in the ODUk ring.

FIG. 5 is a flowchart of Embodiment 3 of a method for notifying rerouting according to the present invention. In this embodiment, according to

The ODUk ring channel alarm is used to determine whether the service is interrupted by the ODUk ring. The peer node of the ODUk ring is the egress ring node of the ODUk ring. As shown in Figure 4 and Figure 5, the following includes:

Step 501: When the link is interrupted, the link will send an ODUk ring channel alarm, and the ODUk ring entry point 01 receives the ODUk ring channel alarm;

Step 502: According to the ODUk ring channel alarm, the ringing node 01 of the ODUk ring determines whether the service on the ODUk ring where the ringing node 01 and its corresponding outgoing node 02 are located is interrupted.

If the ringing node 01 determines that the service is not interrupted, no operation can be performed.

In the case of an ODUk ring channel alarm in the working channel, the ringing node 01 will determine the service interruption, including the following:

In one case, the ring-in node 01 receives the ODUk ring channel alarm sent by the link on the working channel, and then switches the service to the protection channel, and receives the chain on the protection channel after a predetermined time. The ODUk ring channel alarm sent by the road determines the service interruption on the ODUk ring. In the actual application, the link on the working channel is interrupted, and the ODUk ring channel alarm is generated. At this time, the service on the working channel cannot be transmitted. The ring-in node 01 switches the service to the protection channel through the channel switching to continue the transmission. The service is generally 500 ms. The transfer can be resumed on the protection channel. If the link of the protection channel is also interrupted and an ODUk ring channel alarm is issued, the service cannot be transmitted on the protection channel. Since the service may be unstable within a certain period of time when the service is switched from the working channel to the protection channel, first set a predetermined time. If the link on the protection channel issues an ODUk ring channel alarm within the predetermined time, it may be It is caused by the instability when switching occurs. At this time, it is considered that the service can be transmitted on the protection channel; for example, the predetermined time is set to 600ms, within 600ms after the link on the working channel is interrupted and the ODUk ring channel alarm is issued. The ODUk ring channel alarm is generated on the link on the protection channel. This may be caused by the instability when the switchover occurs. In this case, the service can be transmitted on the protection channel. If the link on the protection channel is ODUk ring after 600ms. Channel alarm, indicating service interruption.

In another case, if the ring-in node 01 receives the ODUk ring channel alarm sent by the link on the working channel, and cannot successfully switch the service to the protection channel, the service interruption of the ODUk ring is determined.

Step 503: If it is determined that the service is interrupted, the ringing node 01 of the ODUk ring notifies the peer node of the border node that the outbound node 02 triggers rerouting when the service is not interrupted due to an out-of-loop fault; if it is determined that the service is due to the ring When an external fault is interrupted, no action is required.

Step 504: The loop-out node 02 determines whether an out-of-loop alarm is received to determine whether it is interrupted due to an out-of-loop fault. If the loop-out node 02 does not receive an out-of-loop alarm, indicating that the service interruption is caused by a fault in the ODUk ring, The outgoing node 02 triggers rerouting.

The loop-out node 02 of the ODUk ring determines whether the service interruption is caused by the fault in the ODUk ring. If the loop-out node 02 receives the ring-out alarm, it indicates that the service interruption is not determined by the ODUk. Caused by a fault in the ring, the outgoing node 02 does not trigger rerouting. If the outbound ring node 02 does not receive an outbound alarm, the service interruption is caused by the fault in the ODUk ring, so the outgoing node 02 triggers rerouting. When rerouting, the source node selects an available link to recover the service.

In this embodiment, the ODUk ring service interruption is determined by the ring-entry node of the ODUk ring, and the egress ring node determines whether the service interruption is caused by the ODUk ring failure by determining whether the ring-out alarm is received, and can quickly determine the ODUk ring failure. Triggering re-routing avoids unnecessary triggering of re-routing in the case of no failure in the ODUk ring, which reduces the processing load of the node, saves the time required to determine whether to trigger re-routing, and improves the accuracy of re-routing. effectiveness.

FIG. 6 is a schematic structural diagram of an embodiment of a node device for notifying rerouting according to the present invention. As shown in FIG. 6, the rerouting node device 6 includes a receiving module 61, a determining module 62, and a notifying module 63. The receiving module 61 is configured to receive the ODUk ring channel alarm; the determining module 62 is configured to determine whether the service of the ODUk ring is interrupted according to the ODUk ring channel alarm, and the notification module 63 is configured to notify the opposite end of the node when the service of the ODUk ring is interrupted. The node triggers rerouting when the service is interrupted due to a fault in the ring.

The rerouting node device triggers the rerouting according to the service interruption and the out-of-loop alarm of the ODUk ring, and can quickly and accurately determine the fault in the ODUk ring that causes the service interruption, improve the efficiency and timeliness of triggering the rerouting, and make the interrupted The business is restored in time, which enhances the stability of the network transmission service.

A ring network including an ODUk ring, including a boundary node of an ODUk ring and a peer node of the boundary node, where:

The border node of the ODUk ring is configured to receive the ODUk ring channel alarm, and determine whether the service of the ODUk ring is interrupted according to the ODUk ring channel alarm. If the service of the ODUk ring is interrupted, the border node of the ODUk ring notifies the peer node that the service is in the ring due to the service failure. In case of interruption, trigger re-routing;

The peer node is used to trigger rerouting if the service is interrupted due to a fault in the ring.

The peer node is specifically configured to: when the out-of-loop alarm is not received, determine that the service is interrupted due to a fault in the ring and triggers re-routing.

When the boundary node of the ODUk ring is the ring-in node of the ODUk ring, the peer node is the ring-out node of the ODUk ring. Alternatively, when the boundary node of the ODUk ring is the outgoing node of the ODUk ring, the peer node is the entry point of the ODUk ring. point.

In this embodiment, after the boundary node of the ODUk ring determines that the service of the ODUk ring is interrupted, The end node triggers the re-routing when the service is interrupted due to the fault in the ring. It can ensure that the peer node reroutes only when the fault occurs in the ODUk ring, which reduces the processing load of the node and saves the time required for service recovery. , improve rerouting efficiency.

A person skilled in the art can understand that all or part of the steps of implementing the above method embodiments may be completed by using hardware related to program instructions, and the foregoing program may be stored in a computer readable storage medium, and the program is executed when executed. The steps of the foregoing method embodiments are included; and the foregoing storage medium includes: a medium that can store program codes, such as a ROM, a RAM, a magnetic disk, or an optical disk.

It should be noted that the above embodiments are only for explaining the technical solutions of the present invention, and are not intended to be limiting; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art that: The technical solutions described in the foregoing embodiments are modified, or some of the technical features are equivalently replaced; and the modifications or substitutions do not deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

Rights request

A method for notifying rerouting, comprising:

The method for informing the re-routing according to claim 1, wherein: the boundary node of the ODUk ring is an ingress ring node of the ODUK ring, and the peer node of the ring-entry node is the ODUk ring. Outgoing node

Or the boundary node of the ODUk ring is an outgoing node of the ODUk ring, and the opposite node of the outgoing node is an ingress node of the ODUk ring.

The method for notifying rerouting according to claim 1 or 2, wherein the border node of the ODUk ring notifies the opposite node of the border node to trigger rerouting when the service is interrupted due to an intra-ring failure. Includes:

The border node of the ODUk ring notifies the peer node of the border node whether the service is interrupted due to an intra-ring failure, and triggers re-routing when the service is interrupted due to an intra-ring failure.

The method for notifying the re-routing according to claim 3, wherein the border node of the ODUk ring notifies the peer node of the border node whether the service is interrupted due to an intra-ring fault, including:

The border node of the ODUk ring notifies the peer node of the border node that, if the out-of-loop alarm is not received, it is determined that the service is interrupted due to an intra-ring failure.

The method for informing the re-routing according to claim 1 or 2, wherein determining whether the service of the ODUk ring is interrupted according to the ODUk ring channel alarm includes:

After receiving the ODUk ring channel alarm sent by the link on the working channel, the border node of the ODUk ring switches the service to the protection channel, and receives the ODUk ring channel alarm sent by the link on the protection channel after a predetermined time. Determining that the service of the ODUk ring is interrupted; Alternatively, the border node of the ODUk ring receives the ODUk ring channel alarm sent by the link on the working channel, and fails to successfully switch the service to the protection channel, and then determines that the service of the ODUk ring is interrupted.

6. The method of notifying rerouting according to claim 1, wherein the method further comprises:

After receiving the notification, the peer node triggers rerouting if the service is interrupted due to an intra-ring failure.

7. A node device, comprising:

a receiving module, configured to receive an ODUk ring channel alarm;

a determining module, configured to determine, according to the ODUk ring channel alarm, whether the service of the ODUk ring is interrupted, and a notification module, configured to notify the peer node of the local node in the service when the service of the ODUk ring is interrupted Rerouting is triggered when interrupted due to an in-loop failure.

The node device according to claim 7, wherein the tt module is configured to: if the service of the ODUk ring is interrupted, notify the opposite node of the node to determine whether the service is due to an intra-ring failure. Interrupt, and triggers rerouting when the service is interrupted due to an in-loop failure.

9. A ring network comprising a boundary node of an ODUk ring and a peer node of the boundary node, wherein:

The border node of the ODUk ring is configured to receive an ODUk ring channel alarm, and determine, according to the ODUk ring channel alarm, whether the service of the ODUk ring is interrupted; if the service of the ODUk ring is interrupted, notify the peer node to If the service is interrupted due to a fault in the ring, the re-routing is triggered; after receiving the notification, the peer node triggers re-routing if the service is interrupted due to an intra-ring failure.

10. The ring network of claim 9 wherein:

The boundary node of the ODUk ring is the ringing node of the ODUk ring, and the peer node of the ingress link of the 0DUK ring is the outgoing node of the ODUk ring;

Or the border node of the ODUk ring is an outgoing node of the ODUk ring, and the peer node of the outgoing node of the ODUk ring is an ingress node of the ODUk ring.