CN101686419A - Method of notifying rerouting, node devices and a ring network - Google Patents

Abstract

The invention relates to a method for notifying rerouting, a node device and a ring network. The method for notifying rerouting includes: the boundary node of the optical channel data unit ODUk ring receives an ODUk ring channel alarm, and judges whether the service of the ODUk ring is interrupted according to the ODUk ring channel alarm; if the judgment result is yes, the ODUk ring's The border node notifies its peer node to trigger rerouting when said traffic is interrupted due to a fault within the ring. The node device includes a functional module for executing the above method. The ring network includes the border node of the ODUk ring and the peer node of the border node. In the embodiment of the present invention, after the border node judges that the service of the ODUk ring is interrupted, it notifies its peer node to trigger rerouting when the service is interrupted due to a fault in the ring, which can ensure that the peer node only fails in the ODUk ring where the service is interrupted. Download rerouting to reduce the processing load of nodes, save the time required for business recovery, and improve rerouting efficiency.

Description

Notification method of rerouting, node equipment and ring network

technical field

The invention relates to a wavelength division multiplexing (Wavelength Division Multiplexing, WDM) network technology, in particular to a method for notifying rerouting, node equipment and a ring network.

Background technique

In a WDM network, if a link is interrupted, many services will be interrupted, resulting in the loss of a large amount of data, resulting in significant losses. To this end, ODU1 or ODU2-level overhead byte optical channel data unit (Optical Channel Transport Unit, ODUk) ring protection is created in the WDM network. When the working channel is interrupted, the service will be switched to the protection channel, so that the service can be quickly recover. ODUk ring protection is a channel-level protection mode. This channel-level protection mode in a WDM network is the same as the Multiplexer Section Protection (MSP) mode applied in a Synchronous Digital Hierarchy (SDH) network similar.

In the process of configuring the ODUk ring, the protection group of the ODUk ring must be configured first. As shown in Figure 1, the ring nodes A, B, C, D, E, and F of the ODUk ring protection group are between every two ring nodes. There are two links, namely the working link 1 and the backup link 2 in opposite directions. When the working link 1 is interrupted, the service will be switched from the working channel to the protection channel. The ODUk ring can only be The ring node is switched, and the other ring nodes cannot be switched. If the working link between node A and node B in Figure 1 is interrupted, the service segment cannot be transmitted on the working channel A→B→C, and the channel switching will be performed at the inbound node A and the outbound node C, and the switched service The section will take the protection channel A→F→E→D→C, and the business of service section 1 will not be affected.

Automatically Switched Optical Network (ASON) is a new generation of optical transport network based on WDM network combined with automatic control technology. On the basis of automatic discovery, an end-to-end automatic connection is established through signaling processing and interaction.

ASON has the functions of automatic discovery, automatic service establishment and service restoration. Among them, the automatic discovery function uses Link Management Protocol (Link Management Protocol, LMP) to discover and verify links between two network devices, and uses routing protocols to flood the discovered links in the entire network, so that Each device can know the network topology information; the automatic service establishment function uses automatic control technology, the user only needs to select the source node and destination node related information of the service, and then a service can be automatically established, and the route of the service is optimal; The recovery function is to automatically detect the failure of the service when the service is interrupted, and at the same time automatically establish a new path to restore the interrupted service.

In the event of a network failure such as link interruption or node failure, the ASON control plane will issue an ODUk ring channel alarm, and the network topology information will be updated at the same time. Therefore, in the prior art, the ASON network judges whether the service is interrupted based on the network topology information . If the service is interrupted, the control plane can dynamically re-route according to the network topology information, that is, perform a routing algorithm based on the network topology information, establish a new optical connection and restore the service.

In the process of realizing the present invention, the inventor found that the prior art has at least the following defects: when the above-mentioned link resources change, it is necessary to update the network topology information, that is, the information of the network map, and the information of updating the network map must rely on the routing of the control channel The protocol floods information, and the flooding efficiency of routing information is much lower than that of channel alarms. Therefore, the efficiency of judging ODUk ring failure and rerouting is relatively low, resulting in a relatively long time for service recovery.

Contents of the invention

Embodiments of the present invention provide a method for notifying rerouting, a node device and a ring network to solve the problem of quickly and accurately judging the failure of the ODUk ring and triggering rerouting when a fault occurs in the ODUk ring and causes service interruption.

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

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

If the judgment result is yes, the border node of the ODUk ring notifies its peer node to trigger rerouting when the service is interrupted due to a fault in the ring.

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

A receiving module, configured to receive ODUk ring channel alarms;

A judging module, configured to judge whether the service of the ODUk ring is interrupted according to the ODUk ring channel alarm;

The notification module is configured to notify the peer node of the current node to trigger rerouting when the service is interrupted due to a failure in the ring when the service of the ODUk ring is interrupted.

The embodiment of the present invention also provides a ring network, including a border node of the ODUk ring and a peer node of the border node, wherein the border node of the ODUk ring is used 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 of the border node of the ODUk ring is notified to trigger rerouting when the service is interrupted due to a fault in the ring; The peer node is configured to trigger rerouting when the service is interrupted due to a failure in the ring.

In the above technical solution, after the border node of the ODUk ring judges that the service of the ODUk ring is interrupted, it notifies its peer node to trigger rerouting when the service is interrupted due to a fault in the ring, which can ensure that the peer node is only caused by a fault in the ODUk ring. Rerouting in the case of business interruption, to reduce the processing load of nodes, save the time required for business recovery, and improve rerouting efficiency.

Description of drawings

FIG. 1 is a schematic structural diagram of an ODUk ring protection service in the prior art;

FIG. 2 is a flow chart of Embodiment 1 of the method for notifying rerouting in the present invention;

FIG. 3 is a flow chart of Embodiment 2 of the method for notifying rerouting in the present invention;

FIG. 4 is a schematic diagram of a network structure applied in an embodiment of a method for notifying rerouting in the present invention;

FIG. 5 is a flow chart of Embodiment 3 of the method for notifying rerouting in the present invention;

FIG. 6 is a schematic structural diagram of an embodiment of a node device notifying rerouting in the present invention.

Detailed ways

The technical solutions of the present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

FIG. 2 is a flow chart of Embodiment 1 of the method for notifying rerouting in the present invention. As shown in Figure 2, the rerouting methods may include:

Step 201, the border node of the ODUk ring receives the ODUk ring channel alarm, and judges 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, an ODUk ring channel alarm is issued, and the border node of the ODUk ring initiates to judge whether the service of the ODUk ring is interrupted according to the ODUk ring channel alarm. The border node of the ODUk ring can be the outbound node of the ODUk ring, or It is the ring-entry node of the ODUk ring.

When an ODUk ring channel alarm occurs on the working channel, the boundary node of the ODUk ring will determine whether the service is interrupted, including the following situations:

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, and receives the ODUk message sent by the link on the protection channel after a predetermined time If the ring channel alarms, it is judged that the service of the ODUk ring is interrupted. In practical applications, the link on the working channel is interrupted, and an ODUk ring channel alarm is issued. At this time, the service on the working channel cannot be transmitted, and the boundary node of the ODUk ring switches the service to the protection channel through channel switching to continue transmission. The transmission 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 interruption exceeds the predetermined time. Since the service may be unstable for a certain period of time when the service is just switched from the working channel to the protection channel, set a predetermined time first. If the link on the protection channel sends an ODUk ring channel alarm within the predetermined time, it may It is caused by the instability at the time of the switchover. 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 a predetermined time, it means that the service is interrupted. For example, if the scheduled time is set to 600ms, the link on the protection channel will send an ODUk ring channel alarm within 600ms after the link on the working channel is interrupted and the ODUk ring channel alarm is issued, which may be caused by instability at the time of switching. At this time, it is considered that the service can be transmitted on the protection channel; if an ODUk ring channel alarm occurs on the link on the protection channel after 600 ms, it means that 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, and cannot successfully switch the service to the protection channel, and then judges that the service of the ODUk ring is interrupted.

Step 202, if the border node of the ODUk ring determines that the service of the ODUk ring is interrupted, the border node notifies its peer node to trigger rerouting 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 ring is interrupted, it notifies its peer node whether it has received an alarm outside the ring. If it does not receive an alarm outside the ring, it means that the service is interrupted due to an internal fault, and the peer node triggers rerouting.

When the border node of the ODUk ring determines that the service of the ODUk ring is not interrupted, it may not perform any operation.

For a network that transmits services, nodes are divided into source nodes, destination nodes, and boundary nodes of the ODUk ring. The source node of a service refers to the boundary node where the service enters the network, and the destination node of the service refers to the boundary where the service leaves the network. Node, the boundary node of the ODUk ring can be an in-ring node or an out-ring node. The in-ring node refers to the first node through which the service enters the ODUk ring, and the out-ring node refers to the last node through which the service leaves the ODUk ring.

In this embodiment, when it is judged according to the ODUk ring channel alarm that the boundary node of the ODUk ring where the service is interrupted is the ring-entry node of the ODUk ring, the peer node of the ring-entry node is the ring-out node of the ODUk ring; When the channel alarm determines that the boundary node of the ODUk ring where the service is interrupted is the outbound node of the ODUk ring, the peer node of the outbound node is the inbound node of the ODUk ring.

In the network where the service is transmitted, when the service of the ODUk ring is interrupted, after the border node judges that the service of the ODUK ring is interrupted, it will notify its peer node to trigger rerouting when the service is interrupted due to a fault in the ring, which can ensure that the peer node A node reroutes only when the service is interrupted due to a fault in the ODUk ring where it is located, so as to reduce the processing load of the node, save the time required for service recovery, and improve the rerouting efficiency.

Fig. 3 is the flow chart of embodiment 2 of the method for notifying rerouting of the present invention, in this embodiment, when the node that judges whether the service is interrupted according to the ODUk ring channel alarm is the ring-out node of the ODUk ring, the opposite end of the ring-out node The node is the ingress node of the ODUk ring. As shown in Figure 3, the rerouting methods include:

Step 301, when the link is interrupted, the link will send an ODUk ring channel alarm, and the outgoing node of the ODUk ring receives the ODUk ring channel alarm;

Step 302, according to the ODUk ring channel alarm, the outbound node judges whether the service of the ODUk ring where it is located is interrupted;

If the outbound node judges that the business is not interrupted, it does not need to perform any operation;

Step 303, if it is determined that the service is interrupted, the outbound node notifies its peer node, that is, the inbound node of the ODUk ring, to trigger rerouting when the service is not interrupted due to an out-of-ring fault;

Since the ring-out node and the ring-in node are relative, there may be multiple ODUk rings in a network, and the ring-in node of an ODUk ring may be the ring-in node or the output link of an adjacent ODUk ring other than 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 inbound node of the ODUk ring, to determine whether an out-of-ring alarm is received.

Step 304. The ring-entry node judges whether the service is interrupted due to an out-of-ring fault by judging whether it receives an out-of-ring alarm. If the in-ring node does not receive an out-of-ring alarm, it means that the in-ring node and the out-ring node are in the same location If a fault in the ODUk ring causes service interruption, the ring-entry node triggers rerouting.

The out-of-ring alarm is the ODUk ring channel alarm sent by the link outside the ODUk ring where the ring-in node and the out-ring node are located. If the ring-in node receives an out-of-ring alarm, it cannot be determined that the fault in the ODUk ring caused the service failure. Interruption, so the inbound node does not trigger rerouting. If the ring-entry node does not receive an alarm outside the ring, it can be determined that the service interruption is caused by the fault in the ODUk ring, and the ring-entry node triggers rerouting.

When rerouting, the source node selects an available link to restore the service.

In this embodiment, the service interruption of the ODUk ring where the ODUk ring is located is judged at the ring-out node of the ODUk ring. If the peer node of the ring-out node does not receive an alarm outside the ring, it can quickly determine the fault of the ODUk ring and trigger rerouting, ensuring The ring-entry node of the ODUk ring only reroutes when the service is interrupted due to a fault in the ODUk ring, which reduces the processing load of the node, saves the time required for service recovery, and improves the efficiency of rerouting.

Figure 4 is a schematic diagram of the network structure applied in the embodiment of the method for notifying rerouting in the present invention, as shown in Figure 4, in the network for transmitting services, including: optical fibers, nodes, etc., the services start from user R1 and arrive at user R2, where the node 01 and node 03 are the source node and destination node of the service in the network respectively; the service can start from user R1, pass through the ODUk ring where node 01, node 04 and node 02 are located, and then reach user R2 through node 03, then node 01 is the ring-entry node of the service on the ODUk ring, and node 02 is the ring-out node of the service on the ODUk ring; similarly, the service can start from user R1, pass through node 01, and then pass through the node where node 02, node 04 and node 03 are located When the ODUk ring reaches user R2, node 02 is the ring-entry node of the ODUk ring where the services of node 02, node 04, and node 03 are located, and node 03 is the ring-out node of the service on the ODUk ring.

FIG. 5 is a flow chart of Embodiment 3 of the method for notifying rerouting in the present invention. In this embodiment, the node that judges whether the service is interrupted according to the ODUk ring channel alarm is the ring-entry node of the ODUk ring, and the peer node of the ring-entry node is the ring-out node of the ODUk ring, as shown in Figures 4 and 5. Specifically include:

Step 501, when the link is interrupted, the link will send an ODUk ring channel alarm, and the ring-entry node 01 of the ODUk ring receives the ODUk ring channel alarm;

Step 502: According to the ODUk ring channel alarm, the in-ring node 01 of the ODUk ring judges whether the service on the ODUk ring where the in-ring node 01 and its corresponding out-ring node 02 are located is interrupted.

If the ring-entry node 01 determines that the service is not interrupted, no operation may be performed.

When an ODUk ring channel alarm occurs on the working channel, inbound node 01 will determine that the service is interrupted, including the following situations:

In one case, the ingress node 01 switches the service to the protection channel after receiving the ODUk ring alarm from the link on the working channel, and receives the ODUk ring alarm from the link on the protection channel after a predetermined time. channel alarm, it is determined that the service on the ODUk ring is interrupted. In practical applications, the link on the working channel is interrupted, and an ODUk ring channel alarm is issued. 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 channel switching to continue transmission. The service generally takes 500ms Transmission can be resumed on the protection channel within 10 minutes. If the link of the protection channel is also interrupted and an ODUk ring channel alarm is issued, services cannot be transmitted on the protection channel. Since the service may be unstable for a certain period of time when the service is just switched from the working channel to the protection channel, set a predetermined time first. If the link on the protection channel sends an ODUk ring channel alarm within the predetermined time, it may It is caused by the instability just after the switchover, and it is considered that the service can be transmitted on the protection channel at this time; if the ODUk ring channel alarm occurs on the link on the protection channel after a predetermined time, it means that the service is interrupted. For example, if the scheduled time is set to 600ms, the link on the protection channel will send an ODUk ring channel alarm within 600ms after the link on the working channel is interrupted and the ODUk ring channel alarm is issued, which may be caused by instability at the time of switching. At this time, it is considered that the service can be transmitted on the protection channel; if an ODUk ring channel alarm occurs on the link on the protection channel after 600 ms, it means that the service is interrupted.

In another case, if the ingress node 01 receives an ODUk ring channel alarm from the link on the working channel and cannot successfully switch services to the protection channel, it determines that the ODUk ring service is interrupted.

Step 503, if it is determined that the service is interrupted, the ring-in node 01 of the ODUk ring notifies its peer node, that is, the ring-out node 02, to trigger rerouting when the service is not interrupted due to an out-of-ring fault.

If it is determined that the service is interrupted due to an out-of-ring fault, no operation is required.

Step 504, the ring-out node 02 judges whether it is interrupted due to an out-of-ring fault by judging whether it receives an out-of-ring alarm. If the out-ring node 02 does not receive an out-of-ring alarm, it means that the service interruption is caused by a fault in the ODUk ring, then Outbound node 02 triggers rerouting.

The outgoing node 02 of the ODUk ring determines whether the service interruption is caused by a fault in the ODUk ring according to whether it receives an external alarm. It is caused by a fault, so the outbound node 02 does not trigger rerouting. If the ring-out node 02 does not receive an alarm outside the ring, it means that the service interruption is caused by a fault in the ODUk ring, so the ring-out node 02 triggers rerouting.

When rerouting, the source node selects an available link to restore the service.

In this embodiment, the service interruption of the ODUk ring is judged by the ring-entry node of the ODUk ring, and the service interruption of the ODUk ring is determined by the ring-out node by judging whether an alarm outside the ring is received, which can quickly determine the fault of the ODUk ring and Triggering rerouting avoids unnecessary triggering of rerouting when no fault occurs in the ODUk ring, reduces the processing load of nodes, saves the time required to judge whether to trigger rerouting, and improves the accuracy and reliability of rerouting. efficiency.

FIG. 6 is a schematic structural diagram of an embodiment of a node device notifying rerouting in the present invention. As shown in FIG. 6 , the rerouting node device 6 includes a receiving module 61 , a judgment module 62 , and a notification module 63 . The receiving module 61 is used to receive the ODUk ring channel alarm; the judging module 62 is used to judge whether the service of the ODUk ring is interrupted according to the ODUk ring channel alarm, and the notification module 63 is used to notify the opposite end of the node when the service of the ODUk ring is interrupted Nodes trigger rerouting when services are interrupted due to faults within the ring.

The rerouting node device triggers rerouting according to the service interruption of the ODUk ring and the alarm outside the ring. The business is restored in time, which enhances the stability of the network transmission business.

A ring network comprising an ODUk ring, including a border node of the ODUk ring and a peer node of the border node, wherein:

The border node of the ODUk ring is used to receive the alarm of the ODUk ring channel, and judge whether the service of the ODUk ring is interrupted according to the alarm of the ODUk ring channel; In case of interruption, trigger rerouting;

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

The peer node is specifically used to determine that the service is interrupted due to an intra-ring failure and trigger rerouting without receiving an out-of-ring alarm.

When the border node of the ODUk ring is the ring-entry node of the ODUk ring, the peer node is the ring-out node of the ODUk ring; or, when the border node of the ODUk ring is the ring-out node of the ODUk ring, the peer node is the ring-entry node of the ODUk ring point.

In this embodiment, after the border node of the ODUk ring judges that the service of the ODUk ring is interrupted, it notifies its peer node to trigger rerouting when the service is interrupted due to a fault in the ring, which can ensure that the peer node is only caused by a fault in the ODUk ring. Rerouting in the case of business interruption, to reduce the processing load of nodes, save the time required for business recovery, and improve rerouting efficiency.

Those of ordinary skill in the art can understand that all or part of the steps for realizing the above-mentioned method embodiments can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, the It includes the steps of the above method embodiments; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk and other various media that can store program codes.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be Modifications are made to the technical solutions described in the foregoing embodiments, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims (10)

1. A method for notifying rerouting, comprising: The boundary node of the optical channel data unit ODUk ring receives the ODUk ring channel alarm, and judges whether the service of the ODUk ring is interrupted according to the ODUk ring channel alarm; If the judgment result is yes, the border node of the ODUk ring notifies its peer node to trigger rerouting when the service is interrupted due to a fault in the ring. 2. The method for notifying rerouting according to claim 1, characterized in that: The boundary node of the ODUk ring is a ring-entry node of the ODUK ring, and the peer node of the ring-entry node is a ring-out node of the ODUk ring; Alternatively, the boundary node of the ODUk ring is a ring-out node of the ODUk ring, and the peer node of the ring-out node is a ring-in node of the ODUk ring. 3. The method for notifying rerouting according to claim 1 or 2, wherein the border node of the ODUk ring notifies its peer node to trigger rerouting when the service is interrupted due to a fault in the ring, including: The boundary node of the ODUk ring notifies its peer node to determine whether the service is interrupted due to an internal fault, and triggers rerouting when the service is interrupted due to an internal fault. 4. The method for notifying rerouting according to claim 3, wherein the border node of the ODUk ring notifies its peer node to determine whether the service is interrupted due to a fault in the ring, including: The boundary node of the ODUk ring notifies its peer node that it has determined that the service is interrupted due to an internal fault without receiving an external alarm. 5. The method for notifying rerouting according to claim 1 or 2, wherein judging whether the service of the ODUk ring is interrupted according to the ODUk ring channel alarm includes: The border node of the ODUk ring receives the ODUk ring channel alarm sent by the link on the working channel and 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, It is then determined that the service of the ODUk ring is interrupted; Or, 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, then judges that the service of the ODUk ring is interrupted. 6. The method for notifying rerouting according to claim 1, further comprising: After the peer node receives the notification, if the service is interrupted due to a failure in the ring, rerouting is triggered. 7. A node device, comprising: A receiving module, configured to receive ODUk ring channel alarms; A judging module, configured to judge whether the service of the ODUk ring is interrupted according to the ODUk ring channel alarm; The notification module is configured to notify the peer node of the current node to trigger rerouting when the service is interrupted due to a failure in the ring when the service of the ODUk ring is interrupted. 8. The node device according to claim 7, wherein the notification module is specifically used for: If the service of the ODUk ring is interrupted, notify the peer node of the local node to determine whether the service is interrupted due to an internal fault, and trigger rerouting when the service is interrupted due to an internal fault. 9. A ring network, comprising a border node of an ODUk ring and a peer node of the border node, characterized in that: The border node of the ODUk ring is used to receive an ODUk ring channel alarm, and judge 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, notify the peer node in the When the above-mentioned services are interrupted due to a failure in the ring, rerouting is triggered; After the peer node receives the notification, if the service is interrupted due to a failure in the ring, rerouting is triggered. 10. The ring network according to claim 9, characterized in that: The boundary node of the ODUk ring is the ring-entry node of the ODUk ring, and the opposite end node of the ring-entry node of the ODUK ring is the ring-out node of the ODUk ring; Alternatively, the boundary node of the ODUk ring is the ring-out node of the ODUk ring, and the peer node of the ring-out node of the ODUk ring is the ring-in node of the ODUk ring.

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