WO2017107482A1

WO2017107482A1 - Network protection method and device

Info

Publication number: WO2017107482A1
Application number: PCT/CN2016/091577
Authority: WO
Inventors: 郑钢涛; 万全高; 李海; 申倩倩; 温广娟
Original assignee: 华为技术有限公司
Priority date: 2015-12-26
Filing date: 2016-07-25
Publication date: 2017-06-29
Also published as: CN106921568B; CN106921568A

Abstract

Disclosed is a network protection method, comprising: after a bidirectional signal fail (SF) occurs on a working path for communication between a first node and a second node adjacent to the first node in a ring network, and causes the service traffic transmission path to be switched from the working path to a protection path, if an SF or a signal degrade (SD) occurs between a third node and a fourth node adjacent to the third node on the working path, and if the first node does not receive from the working path a ring-network automatic protection switching (APS) message sent by the second node when the SF occurring in the direction from the second node to the first node is eliminated, determining that the SF occurring in the direction from the first node to the second node is not eliminated, and keeping service traffic being transmitted by means of the protection path. The solution of the present application effectively reduces occurrence of the problem of service interruption caused by asynchronous elimination of a bidirectional SF occurring between certain nodes after a multipoint link fail in a service transmission path, and improves the reliability of service transmission.

Description

Network protection method and device

The present application claims priority to Chinese Patent Application No. 20151099281, filed on Dec. 26, 2015, the entire disclosure of which is incorporated herein by reference. .

Technical field

The present invention relates to the field of communications technologies, and in particular, to a network protection method and apparatus.

Background technique

In the Packet Transport Network (PTN), the current network protection switching mechanism for major applications includes automatic protection switching (APS) and linear APS, and both protection switching mechanisms are used. There is a common problem. When there is a two-way signal failure in the network service transmission path (English: signal fail, SF) and the fault elimination is not synchronized, that is, only one-way SF is eliminated, the service is interrupted, and the service is the longest. The interruption time can reach 5 seconds.

Summary of the invention

The present application provides a network protection method and apparatus to reduce the service interruption problem caused by the non-synchronization of the two-way signal failure in the service transmission path of the network system.

In a first aspect, the application provides a network protection method, where the method includes:

When a working path of communication between the first node of the ring network and the second node adjacent to the first node occurs a bidirectional signal failure SF, causing the transmission path of the service traffic to be switched from the working path to the protection path, if On the working path, a third node to a fourth node adjacent to the third node generates SF or signal degradation SD, and on the working path, from the second node to the first node When the SF is removed, the first node does not receive the ring network automatic protection switching APS packet sent by the second node from the working path, and determines that the first node to the working path The SF in the direction of the second node is not eliminated, and the service traffic is kept transmitted through the protection path;

The service traffic is transmitted through the first node, the second node, the third node, and the fourth node on the working path.

According to the above technical solution, when the SF of the second path to the first node is eliminated in the working path, and the first node does not receive the ring network APS message sent by the second node from the working path, the default is The SF in the working path from the first node to the second node direction is not eliminated. The state machine of the first node is prevented from responding to the high priority switching request sent by the fourth node while waiting for the recovery time period, thereby avoiding using the working path of the possible SF for the service transmission path. The service interruption problem caused by the unsynchronized two-way SF elimination in the network transmission is effectively reduced, and the reliability of the network service transmission is improved.

Further, optionally, the maintaining the service traffic is transmitted by using the protection path, where: when the first node does not receive the APS packet sent by the second node from the working path, The state machine switching state of the first node remains unchanged.

The state machine switching state of the first node remains unchanged, that is, the first node does not respond to the switching request sent by the fourth node, and the switching request sent by the fourth node has a higher priority than the first node. The state priority of the node.

Since the first node does not respond to the high-priority switching request sent by the fourth node, the state machine of the first node can continue to wait for the recovery of the WTR state, and therefore, the transmission path of the service is not switched to the work that may still have a signal failure. The path reduces the problem of service interruption and improves the stability of service transmission.

In a second aspect, the present application provides another network protection method, where the method includes:

When the working path communicated between the first node and the second node adjacent to the first node generates a bidirectional signal degradation SD, a bidirectional signal failure occurs in a protection path between the first node and the second node. SF, when traffic is transmitted on the working path; if the SF on the protection path from the second node to the first node is eliminated, and the first node is not received from the protection path The linear automatic protection switching APS packet sent by the second node determines that the SF in the direction of the first node to the second node in the protection path is not eliminated, and the service traffic is kept through the Work path transfer.

According to the above technical solution, when the working path has a bidirectional SD and the protection path unidirectional SF is eliminated, and the first node does not receive the APS packet sent by the second node, the SF of the first path in the other direction is defaulted. Not eliminated, keeping the traffic flowing through the working path. Thereby, the protection path that may still exist SF is avoided for the service transmission path. It effectively reduces the problem of service interruption caused by inconsistent two-way SF in the network transmission, and improves the reliability of network service transmission.

When the first node receives the APS packet sent by the second node from the protection path, the first node performs protection switching according to the indication of the APS packet.

In a third aspect, the present application provides a network protection device, where the device includes: a detecting unit and a service protection unit, where

When a working path of communication between the first node of the ring network and the second node adjacent to the first node occurs a bidirectional signal failure SF, causing the transmission path of the service traffic to be switched from the working path to the protection path, if On the working path, the third node to the fourth node adjacent to the third node generates SF or signal degradation SD, and the detecting unit determines that the second node to the first node on the working path If the SF is removed from the direction, the service protection unit determines that the first node does not receive the ring network automatic protection switching APS packet sent by the second node from the working path, and the service protection unit determines that On the working path, the SF in the direction from the first node to the second node is not eliminated, and the service traffic is kept transmitted through the protection path;

Optionally, the device is located on the first node side.

Optionally, the service protection unit is further configured to: when the first node receives the APS packet sent by the second node from the working path, instruct the first node to follow the APS The indication of the packet is protected and switched.

Further optionally, the service protection unit is further configured to: when the first node does not work from the Receiving, by the second node, the APS packet sent by the second node, indicating that the first node does not respond to the switching request sent by the fourth node, and the switching request sent by the fourth node has a higher priority The state priority of the first node.

This solution has the same technical effect as the solution of the first aspect.

In a fourth aspect, the application further provides a network protection device, where the device includes a detecting unit and a service protection unit, where

When the working path communicated between the first node and the second node adjacent to the first node generates a bidirectional signal degradation SD, a bidirectional signal failure occurs in a protection path between the first node and the second node. SF, when the service traffic is transmitted in the working path, if the detecting unit determines that the SF is removed from the second node to the first node in the protection path, and the service protection unit determines If the first node does not receive the linear automatic protection switching APS packet sent by the second node from the protection path, the service protection unit determines the first node to the second in the protection path. The SF in the node direction is not eliminated, and the traffic is kept transmitted through the working path.

Optionally, the device is located on the first node side.

Optionally, the service protection unit is further configured to: when the first node receives the APS packet sent by the second node from the protection path, instruct the first node to follow the APS The indication of the packet is protected and switched.

This solution has the same technical effect as the solution of the second aspect.

In a fifth aspect, the application provides a network protection device, where the device includes a memory and a processor;

The memory is configured to store information including a program, an instruction or a code; the processor is configured to execute a program, an instruction or a code in the memory, and the method of the first aspect or the second aspect is completed.

Optionally, the memory communicates with the processor through a bus;

Optionally, the processor communicates with an adjacent node device through a network interface.

In a sixth aspect, the application further provides a communication system, including a first node, a second node, and a network protection device, where the network protection device is the network protection device of the third aspect or the fourth aspect The network protection device described. The communication system can perform the method of the first aspect or the second aspect.

In accordance with any of the first to sixth aspects, the first node, the second node, the third node, and the fourth node may be routers, switches, firewalls, packet switched network devices, and the like.

DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings to be used in the embodiments will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without paying any creative work.

1A, FIG. 1B, and FIG. 1C are schematic diagrams of an APS scenario according to an embodiment of a network protection method provided by the present application;

2 is a schematic diagram of an implementation method involved in an embodiment of a network protection method provided by the present application;

3 is a flowchart of a method involved in an embodiment of a network protection method provided by the present application;

FIG. 4 is a schematic diagram of an application scenario involved in another embodiment of a network protection method according to the present invention;

FIG. 5 is a schematic diagram of an implementation method according to another embodiment of a network protection method provided by the present application;

FIG. 6 is a flowchart of a method involved in another embodiment of a network protection method according to the present application;

FIG. 7 is a schematic diagram of a network protection device according to an embodiment of the present application;

FIG. 8 is a schematic diagram of a network protection device according to another embodiment of the present application.

detailed description

The application scenarios described in the embodiments of the present application are for the purpose of more clearly explaining the technical solutions of the embodiments of the present application, and do not constitute a limitation of the technical solutions provided by the embodiments of the present application. Those skilled in the art may understand that with the evolution of the network architecture and The technical solutions provided by the embodiments of the present application are equally applicable to similar technical problems.

In the present application, "communication" and "transmission" are often used interchangeably. This application sometimes uses "local node" and "peer node" to refer to "first node" and "second node", specifically, The execution body of the method step is called "the local node", and the node that communicates with the execution subject is called the "peer node". These are all understood by those skilled in the art. The nodes involved in the present application may include switches, routers, firewalls, packet transport network devices, and the like. For convenience of description, the devices mentioned above are collectively referred to as nodes in the present application.

The working path described in this application refers to the path for service traffic transmission that is set by default in the normal state. The protection path refers to the path for service traffic transmission instead of the working path when the working path cannot transmit service traffic. The working path or the protection path involved in the present application may be a physical layer optical fiber, or may be any one or more of a logical layer of a pseudowire or a tunnel. For convenience of description, the present application is collectively referred to as a working path or a protection path.

The transmission link described in the present application includes a link for traffic transmission in a working path, and a link for transmission of service traffic in the protection path. It should be noted that the transmission link of the working path and the protection path are two different links, for example, two different optical fibers.

In the embodiment of the present application, the working path from the transmitting end of the local node to the receiving end of the opposite end node, and the working path of the transmitting end of the opposite end node to the receiving end of the local end node may be physically the same link. (for example, the same fiber, etc.), or two different links (for example, two different fibers). Those skilled in the art can understand that the working paths in two directions may be the same link or different links. The protection path setting is the same as the working path, and will not be described again.

In the present application, the identification of the transmission link is carried out with Arabic numerals, which is used only for the illustrative representation of the location of the transmission link including the working path and the protection path between the node devices. Those skilled in the art can know the specific link used by the service traffic through the specific description in the embodiment.

The "ring protection protocol" mentioned in this application may be any version of ITU-T G.8132, and the "linear protection protocol" may be any version of ITU-T G.8031. The linear APS protocol described in this application may be a linear APS protocol as described in any version of ITU-T G.8031.

Example 1

1A, 1B, and 1C are schematic diagrams of an application scenario involved in an embodiment of a network protection method for a ring network APS provided by the present application. As shown in FIG. 1A, a base station 1 is connected to a section on a ring network. Point 1, Node 2, Node 3, Node 4, Node 5, Node 6 and Radio Network Controller RNC1 communicate. Wherein: node 1 and node 2 communicate via transmission link 1; node 2 and node 3 communicate via transmission link 2; node 3 and node 4 communicate via transmission link 3; node 4 and node 5 Communication is carried out through the transmission link 4; the node 5 and the node 6 communicate via the transmission link 5; the node 6 and the node 1 communicate via the transmission link 6.

The traffic flows through the base station 1 to the upper ring node 2 of the ring network, and the ring network includes node 1, node 2, node 3, node 4, node 5, node 6, and a transmission link between the nodes, and the ring network is deployed. There is ring network protection. The ring network is deployed with a working path and a protection path. Take FIG. 1A as an example. The service traffic sent by the base station 1 is ringed from the node 2 and the slave node 5 is looped. For the service traffic, the working path in the counterclockwise direction is set by default on the ring network. The normal working path for the traffic transmission, the clockwise protection path is to provide transmission protection for the service traffic when the working path fails. When traffic is looped from node 2 and slave 5 is down, in normal working state, the transmission path of service traffic is node 2 -> node 1 -> node 6 -> node 5, that is, the service traffic works on the ring network. The path is Node 2 -> Node 1 -> Node 6 -> Node 5, and the protection path of the service traffic on the ring network is Node 2 -> Node 3 -> Node 4 -> Node 5.

When the node or the transmission link of the upper ring node and the lower ring node fails, the transmission path of the service traffic on the ring network is switched, that is, the transmission path of the service traffic is switched from the working path to the working path. Protection path. For example, if node 1 fails or a link barrier occurs between the transmission link between node 2 and node 1, the transmission path of the service traffic is switched, and the working path is switched to the protection path, that is, the transmission path of the service traffic on the ring. It is node 2 -> node 3 -> node 4 -> node 5.

FIG. 1B is a schematic diagram of an APS scenario when a multi-point link failure occurs in a ring network of the embodiment of the present application, and a bidirectional SF occurs between one node; FIG. 1C shows a ring network SF shown in FIG. 1B. Schematic diagram of the APS scene when it is eliminated. The above link failures include bidirectional SF, one-way SF, two-way signal degradation (English: signal degrade, SD) and one-way SD between nodes. In the scenario shown in FIG. 1B and FIG. 1C, it is assumed that the protection path does not fail, and the base station 1 transmits to the RNC1. The business traffic is illustrated as an example. Referring to FIG. 1B, the ring network includes node 1, node 2, node 3, node 4, node 5, and node 6, each of which will be clockwise (hereinafter referred to as "E direction") and counterclockwise (hereinafter referred to as The message is sent in both directions in the "W direction". Therefore, if the packet is transmitted along the transmission link in the W direction, node 1, node 2, node 3, node 4, node 5, and node 6 on the transmission path are respectively marked. 1_W, 2_W, 3_W, 4_W, 5_W, 6_W; if the message is transmitted along the transmission link in the E direction, node 1, node 2, node 3, node 4, node 5, and node 6 on the transmission path are respectively marked. It is 1_E, 2_E, 3_E, 4_E, 5_E, 6_E.

The service traffic reaches the node 2 of the ring network through the base station 1. The service traffic is set to the upper ring of the node 2_W, and the ring is disconnected by the node 5_E. The ring network is set to counterclockwise direction for its normal working direction by default, and the clockwise direction is the protection working direction. Therefore, when the service traffic reaches the ring network node 2_W, under normal working conditions, in the counterclockwise direction, the slave node 2_W rings, and the slave node 5_E rings, that is, the service traffic on the ring network is the node 2 -> Node 1 -> Node 6 -> Node 5. When a multipoint link failure occurs on the ring, for example, a bidirectional SF occurs between the working path between the node 2_W and the node 1_E, and a working path between the node 6_W and the node 5_E appears SF or SD. The SF is generated by the working path between the node 2_W and the node 1_E, and the SF is generated by the node 6_W to the node 5_E. According to the ring network protection protocol, the node 1_E, the node 2-W, the nodes 5_E, and 6_W all enter the SF reversal state SWITCH_SF. All other nodes on the ring enter the SF through state PASS_SF. At this time, the transmission path of the service traffic is switched from the counterclockwise working path to the clockwise protection path, and the service traffic is transmitted from the node 2_W to the ring, along the clockwise protection path, and from the node 5_E to the RNC1. Therefore, although a multipoint link failure occurs in the normal working path, the transmission of traffic is still not interrupted.

As shown in FIG. 1C, when the SF of the node 6_W to the node 5_E direction has not been eliminated, and the SF of the node 1_E to the node 2_W direction is eliminated, the local end of the node 2_W detects that the traffic reception direction SF is eliminated, and the state opportunity of the local end of the node 2_W changes first. Is the SWITCH_WTR state. The normal transmission period of the APS packet is 5 seconds. Although the SF of the node 2_W traffic receiving direction is eliminated, the peer node 1_E needs to wait for 5 seconds before sending the APS packet to the 2_W. During this 5 second send cycle, the festival The point 2_W cannot receive the APS packet sent by the peer node 1_E, so it is impossible to determine whether the SF in the receiving direction of the peer node 1_E is eliminated. Since the SF still exists in the direction of the node 6_W to the node 5_E at this time, according to the ring network protection protocol, the node 2_W receives the APS message that the node 5_E sends in the counterclockwise direction to the node 2_W indicating that the SF is in the direction of the node 6_W to the node 5_E. The priority request of the APS packet identifying the SF is higher than the priority of the node 2_W request to resume (WTR). Therefore, according to the ring protection protocol, the state opportunity of the node 2_W enters the PASS_SF by the SWITCH_WTR. Node 2 will be switched back to the working path by the protection path. When the traffic is sent from the node 2_W, the traffic will be transmitted along the default counterclockwise working path. However, since the working path of the node 2_W to the node 1_E is still SF, the traffic is traffic. Unable to transmit, the SF in the direction of the node 2_W to the node 1_E is also eliminated, or wait until the node 2_W receives the APS packet sent by the node 1_E and re-enters the SF reversal state, and the working path is switched to the protection path. The transmission of service traffic can be restored, and the APS packet transmission period is 5 seconds. Therefore, in this process, the maximum service interruption time is 5 seconds.

For the working path between the node 2_W and the node 1_E, a bidirectional SF occurs, a node 6_W to the node 5_E generates an SD scenario, a working path between the node 2_W and the node 1_E generates a bidirectional SF, and a scenario where the node 6_W to the node 5_E generates an SF is similar. . For the same parts of the two scenes, we will not go into details. The following focuses on the different aspects of the two scenarios. When the SD in the direction of the node 6_W to the node 5_E has not been eliminated, and the SF in the direction of the node 1_E to the node 2_W is eliminated, if the node 2_W does not receive the APS packet sent by the peer node 1_E from the working path, according to the ring network protection protocol, the node 2_W The received APS message sent by the node 5_E in the counterclockwise direction to the node 2_W indicating the occurrence of SD in the direction of the node 6_W to the node 5_E. The priority request of the APS packet identifying the SD is higher than the priority of the node 2_W requesting the WTR. Therefore, according to the ring protection protocol, the state opportunity of the node 2_W enters the PASS_SD by the SWITCH_WTR. Node 2 will be switched back to the working path by the protection path. When the traffic is sent from the node 2_W, the traffic will be transmitted along the default counterclockwise working path. However, since the working path of the node 2_W to the node 1_E is still SF, the traffic is traffic. Unable to transfer.

The network protection method will be described in detail below with reference to FIGS. 2 and 3. In this embodiment, the network protection method is applied to the node 2 shown in FIG. 2, and the SF is generated by the node 6_W to the node 5_E.

S301, a working path of communication between the first node and the adjacent second node occurs in a bidirectional SF, and after the transmission path of the service traffic is switched from the working path to the protection path, if the working path is on the third node to The fourth node adjacent to the third node generates an SF, and the SF of the second node to the first node is eliminated, determining whether the first node receives the ring network automatic protection switching APS sent by the second node. Message.

If the first node receives the APS packet sent by the second node, the state machine of the first node determines whether to switch according to the APS packet request.

The first node may be any node on the ring for transmitting current service traffic, and the current service traffic is in the normal working path, and after being transmitted to the second node after passing through the first node. In this embodiment, node 2 is used as the first node, node 1 is used as the second node, node 6 is used as the third node, and node 5 is used as the fourth node for illustration.

Normally, the traffic from the base station 1 to the upper ring node 2_W, in the default counterclockwise working direction, sequentially arrives at the RNC 1 via the node 1, the node 6, and the lower ring node 5_E. The detecting unit detects that the working path between the node 1_E and the node 2_W has a bidirectional SF, and the working path occurrence SF of the node 6_W to the node 5_E. In the embodiment of the present application, the detecting unit is located in each node device, and the function of the detecting unit can be implemented through an Operation, Administration, and Maintenance (OAM) unit. The OAM mechanism tests the message through the timing interaction between the nodes. To report the link status between nodes. After detecting that the working path between the node 1_E and the node 2_W occurs in the bidirectional SF and the working path in the direction of the node 6_W to the node 5_E occurs SF, the node 2_W enters the SWITCH_SF state, and the service traffic transmission path that reaches the 5_E via the node 2_W is reversed. The working path of the hour hand is switched to the clockwise protection path, and the traffic flow is transmitted from the node 2_W to the ring in a clockwise direction, and the slave node 5_E is looped. When the SF cancellation in the direction of the node 1 to the node 2 is detected, the node 2_W is changed from the SWICH_SF state to waiting for the recovery of the reverse state. SWITCH_WTR. The node 2_W determines whether the APS packet sent by the node 1_E is received from the working path, and the APS packet is used to indicate whether the node 2_W performs protection switching.

In this embodiment, when the node 2_W receives the APS message including the SF switching request sent by the node 1_E, indicating that the working path of the node 2_W to the node 1_E still has the SF, the node 2_W enters the SWITCH_SF state by the SWITCH_WTR state, and the service The traffic remains in the protection path. The traffic is looped on the node 2_W, and is transmitted along the clockwise protection path to the node 5_E, and the node 5_E is looped.

When the node 2_W receives the APS message of the non-switching request sent by the node 1_E, it indicates that the working path SF in the direction of the node 2_W to the node 1_E has been eliminated. If the SF still exists in the node 6_W to the node 5_E, according to the ring network protection protocol, The node 2_W enters the PASS_SF state from the SWITCH_WTR state, and the transmission path of the service traffic is switched back from the protection path to the working path. The traffic is transmitted from the node 2_W to the ring and along the counterclockwise working path to the node 6_W. After the service traffic reaches the node 6_W, the service traffic cannot be transmitted through the working path of the node 6_W to the node 5_E due to the SF in the direction of the node 6_W to the node 5_E. According to the ring network protection protocol, the node 6_W switches to the protection path to transmit the current service traffic. That is, in the clockwise direction, the node 1, the node 2, the node 3, and the node 4 are successively passed to the node 5_E, and the slave node 5_E is looped. That is, when the two-way SF between the node 2_W and the node 1_E is eliminated, and the node 6_W to the node 5_E still have the SF, the transmission path of the traffic in the ring network is: node 2 -> node 1 -> node 6 -> node 1—>Node 2—>Node 3—>Node 4—>Node 5. Until the working path SF between the node 6_W and the node 5_E is eliminated, the service traffic is switched back to the normal working path, and the slave node 2_W is ringed, the node 1 and the node 6 are looped at the node 5_E.

S302: If the first node does not receive the APS packet sent by the second node from the working path, the first node determines that the SF in the direction from the first node to the second node is not Eliminate and keep the currently transmitted traffic flowing on the protection path.

In this embodiment, when the node 2_W does not receive the APS packet sent from the neighboring node 1_E, it is considered that the SF still exists in the direction of the node 2_W to the node 1_E, and the node 2_W remains in the node 2_W. In the SWITCH_WTR state, the non-responding node 5_E sends the APS message switching request of the SF in the counterclockwise direction to the node 2_W indicating that the node 6_W to the node 5_E, that is, the inbound state machine of the node 2_W does not respond to the other state machine. A switching request with a higher priority than the current state. At this time, the traffic is still transmitted on the protection path. That is, when the traffic is looped from the node 2_W, it still goes clockwise, passes through node 3 and node 4, and is disconnected by node 5_E. The traffic path in the ring network is consistent with the transmission path of the traffic in the network when the two-way SF occurs between the previous node 2_W and the node 1_E, that is, the service traffic continues to be transmitted on the protection path.

In summary, the network protection method provided in this embodiment has a multi-point link failure in the ring network, and a bidirectional SF occurs between one of the nodes, and another link between the nodes on the ring still has a link failure. When the SF unidirectional cancellation occurs in the bidirectional SF, it is first determined whether the SF cancellation node receives the APS packet sent by the peer node, and if the node does not receive the APS packet, the node is considered to be The SF in the direction of the end node is not eliminated, and the transmission path of the currently transmitted service traffic in the network is consistent with the transmission path of the service traffic in the network when the bidirectional SF occurs. Therefore, the service traffic is effectively reduced in the network transmission, and in the case of a multi-point link failure in the ring network, the service interruption problem caused by the unsynchronized bidirectional SF elimination between one of the nodes improves the reliability of the network service transmission. .

Example 2:

Referring to FIG. 4, it is a schematic diagram of an application scenario of an embodiment of a network protection method for a linear APS provided by the present invention. The first node A and the second node B are node devices in a service traffic transmission path, and the base station passes the first node. A and the second Node B communicate with the RNC. The communication path between the first node A and the second node B includes a working path (solid line as shown in FIG. 4) and a protection path (dashed line as shown in FIG. 4), and the working path and the protection path are Two different links. The link is a logical link or a physical link. When the working path of communication between the first node A and the second node B has a bidirectional SD, and the protection path of communication between the first node A and the second node B has a bidirectional SF, the service traffic sent by the base station passes through the first node. A is transmitted to the second node B, due to The protection path is a bidirectional SF, and the traffic is transmitted by the first node A to the second node B via the working path. Although there is a two-way SD in the working path, the service can still pass and is not completely interrupted; when the second node B to the first node A in the protection path is unidirectionally SF eliminated, the second node B keeps the traffic in the working path, and the second A node A switches traffic to the protection path and chooses to send traffic from the protection path. However, the SF of the protection path direction of the first node A to the second node B is not eliminated at this time, and therefore, a service interruption occurs at this time.

The linear APS protocol defines two protection mechanisms: 1+1 protection switching and 1:1 protection switching. In the 1+1 protection switching mechanism, the transmitting end simultaneously transmits the service in the working path and the protection path, and the receiving end selects one path in the working path and the protection path to receive the service. In the 1:1 protection switching mechanism, the sender and the receiver transmit the primary service on the working path. The protection path does not transmit services or only transmits some low-priority service traffic. When the working path fails, the sender sends the service. The end and the receiving end switch to the protection path to transmit the main service. In the embodiment of the present application, the APS may be a 1+1 protection switching mechanism or a 1:1 protection switching mechanism.

A one-way protection switching mechanism and a two-way protection switching mechanism are also defined in the linear APS protocol. Taking the application scenario shown in FIG. 4 as an example, if the working path of the first node A to the receiving end of the second node B fails, in the one-way protection switching mechanism, only the direction of the failure occurs. The service traffic is switched to the protection path for transmission, and the service transmission between the sender of the second node B and the receiver of the first node A still keeps the working path from being switched. In the bidirectional protection switching mechanism, traffic transmissions in both directions are switched to the protection path. The linear APS mechanism of the embodiment of the present application is a bidirectional protection switching mechanism.

The network protection method provided by the present application is described in detail below with reference to FIG. 5 and FIG. 6.

This embodiment is exemplified by applying the network protection method to the node device shown in FIG. 5. When the working path of communication between the first node A and the second node B (solid line as shown in FIG. 5) occurs in a bidirectional SD, and the protection path (dashed line as shown in FIG. 5) generates a bidirectional SF, according to the linear APS protocol The first node A and the second node B maintain the transmission path of the traffic flow on the working path. after that,

S601. If the working path of the communication between the first node and the second node is not eliminated, And the unidirectional SF cancellation occurs in the protection path of the communication between the first node and the second node, determining whether the first node receives the linear automatic protection switching APS packet sent by the second node.

If the first node receives the APS packet sent by the second node, the first node determines whether to perform the switching according to the APS packet.

In this embodiment, the first node may be any node on the network for transmitting service traffic, and the service traffic sent by the base station reaches the second node B through the first node A. Normally, when the service traffic reaches the first node A from the base station, the service path is selected to be transmitted by the working path. When the working path between the first node A and the second node B appears bidirectional SD, and the protection path is normal, the traffic is switched from the working path to the protection path for transmission. In the process of the service traffic transmission, the detecting unit detects the link state between the first node A and the second node B, and the detecting unit may be an OAM unit located in each node device, and the OAM mechanism tests the message through the timing interaction between the nodes. To report the link status between nodes. When the detecting unit detects that the working path between the first node A and the second node B still has a bidirectional SD, the protection path generates a bidirectional SF, and at this time, the first node A and the second node B are switched by the protection path to Working path; in this state, the second node B enters the SF_P(0,0) state, the second node B switches to the working path; and the first node A also enters the SF_P(0,0) state, the first node A is also Switch to the working path. SF_P(0,0) indicates the protection path SF, and the service traffic is switched to the working path transmission.

When the SF of the protection path is removed in the direction from the second node B to the first node A, the first node A receives the APS packet including the SF switching request sent by the second node B, indicating that the first node A to the second node The protection path of Node B still exists SF. The second node B continues to remain in the SF_P(0,0) state, the state is unchanged, remains in the working path, and sends the SF_P(0,0) message to the first node A every 5 seconds. The first node A receives the SF_P(0,0) request message sent by the second node B, and according to the linear APS protocol, the first node A enters NR_W(0, 0) and remains in the working path. NR_W(0,0) indicates that the working path has no switching request, and the traffic is transmitted on the working path.

S602: If the first node does not receive the APS packet sent by the second node from the protection path, the first node determines the SF in the direction of the first node to the second node in the protection path. Unremoved, continue to maintain the traffic traffic currently transmitted on the working path.

In this embodiment, although the SF cancellation in the receiving direction of the first node A, before the first node A does not receive the APS packet sent by the second node B, the switching request of the second node B is still SF_P (0). , 0). The second node B continues to remain in the SF_P(0,0) state, the state remains unchanged, remains in the working path, and the SF_P(0,0) message is sent to the first node A for a period of 5 seconds, during which the first node A default peer request is SF_P(0,0), and the local end enters NR_W(0,0) to keep the current traffic on the working path.

When the bidirectional SF of the protection path between the first node A and the second node B is eliminated, and the second node B does not receive the APS message sent by the first node A from the protection path, the second node B The state machine switches to the NR_W(0,0) state, the second node B remains in the working path, and the second node B sends the APS message including the NR_W(0,0) request to the first node A; the first node A receives the first The AES packet sent by the two-node B includes the NR_W (0, 0) request, the state machine of the first node A enters the SD_W (1, 1) state, and the SD_W (1, 1) state indicates that the working path exists SD, and the service traffic is Protection path transmission. The first node A switches back to the protection path and sends an APS message including the SD_W (1, 1) request to the second node B. The second node B receives the APS packet sent by the first node A and includes the SD_W (1, 1) request, the state machine of the second node B enters the SD_W (1, 1) state, and the second node B switches back to the protection path. . The first node A receives the APS packet including the SD_W (1, 1) request sent by the second node B when the state machine of the first node A is in the SD_W (1, 1) state, and the state machine of the first node A The state is unchanged, and the first node A remains in the protection path, thereby ensuring normal transmission of traffic.

When the bidirectional SD of the working path between the first node A and the second node B is eliminated, the first node A and the second node B cut back the transmission path of the traffic flow to the working path.

In summary, the present embodiment provides a network protection method for a linear APS. After a bidirectional SD occurs in a working path between a first node of the network and an adjacent second node, the transmission path of the service traffic is switched to the protection path, and the protection is performed. A bidirectional SF occurs in the path, the traffic is switched to the working path, and then the one-way SF in the bidirectional SF of the protection path is eliminated, and the first node is not on the protection path. When receiving the APS packet sent by the adjacent second node, determining that the SF on the protection path in the direction from the first node to the second node is not eliminated, and continuing to transmit the service traffic on the working path without switching to the one-way SF. Eliminated protection path. With the method of the embodiment of the present application, when the two-way SF fault elimination of the service transmission path is not synchronized, the service interruption can be reduced, and the reliability of the service transmission can be improved.

It can be understood by those skilled in the art that all or part of the steps of implementing the above method embodiments may be completed by hardware related to program instructions, and the foregoing program may be stored in a computer readable storage medium, and when executed, the program includes The steps of the foregoing method embodiments, and the foregoing storage medium includes: a read-only memory ROM, a random access memory RAM, a magnetic disk, or an optical disk, and the like, which can store program codes.

Example 3:

In order to perform the network protection method in the foregoing embodiment, the embodiment of the present invention provides a network protection device, where the network protection device may be located on the first node side or the second node side in Embodiment 1, or the network protection device may It is located on the first node or the second node in Embodiment 1. Referring to FIG. 7, the network protection device includes: a detecting unit and a service protection unit, where

The detecting unit is configured to determine whether a communication failure occurs between the first node and the adjacent second node;

The detecting unit may be an OAM unit located in the node device, and the OAM reports the link status between the nodes by using a timed interaction test message between the nodes to detect whether the link is faulty. When the OAM unit detects the bidirectional SF, the unidirectional SF, the unidirectional SD, and the bidirectional SD between the nodes, the fault type is notified to the faulty node, and the service protection unit performs the transmission of the service traffic according to the detection result of the detecting unit. protection. When the detecting unit detects that the transmission path between the first node and the adjacent second node generates a bidirectional SF, the transmission path of the service traffic is switched from the first path to the second path to ensure normal transmission of service traffic. .

The service protection unit is configured to perform service protection according to the detection result of the detecting unit;

In the ring network APS scenario, when a two-way SF occurs between the first node and the second node adjacent to the first node, the traffic path of the service traffic is switched from the working path to the protection path, if The third node generates SF or SD to a fourth node adjacent to the third node, and the detecting unit determines SF elimination on the working path from the second node to the first node direction, where The service protection unit determines that the first node does not receive the ring network APS message sent by the second node from the working path, and the service protection unit determines that the first node is on the working path. The SF to the second node direction is not eliminated, and the service traffic is maintained to be transmitted through the protection path;

Optionally, the service protection unit is further configured to: when the first node receives the APS packet sent by the second node, instruct the first node to perform protection switching according to the request of the APS packet.

Further, optionally, the service protection unit is further configured to: when the first node does not receive the APS packet sent by the second node from the working path, indicating that the first node does not respond to the The switching request sent by the fourth node is performed, and the switching request sent by the fourth node has a higher priority than the first node.

In the linear APS scenario, the working path of communication between the first node and the adjacent second node generates a bidirectional SD, the protection path generates a bidirectional SF, and the service traffic is transmitted during the working path; if the detecting unit determines that the protection is in the protection The SF in the path from the second node to the first node is eliminated, and the service protection unit determines that the first node does not receive the linear automatic protection sent by the second node from the protection path. If the APS packet is switched, the service protection unit determines that the SF in the direction from the first node to the second node is not eliminated, and the service traffic is transmitted through the working path.

The service protection unit or the detecting unit may be implemented by a circuit, or may be implemented by hardware related to program instructions, and the hardware may be variously known to those skilled in the art. The device, for example, can be a network processor (English: Network Processor, NP), a central processing unit (English: Central Processing Unit, CPU), and the like.

Example 4:

FIG. 8 is a diagram showing another network protection device according to an embodiment of the present invention, where the network protection device is located on the first node side of Embodiment 1, or the network protection device is located on the first node side of Embodiment 2, or The network protection device is located at the first node of Embodiment 1, or the network protection device is located at the first node side of Embodiment 2.

As shown in FIG. 8, the network protection device includes a memory 101 and a processor 102. The memory 101 and the processor 102 can communicate over a bus 103; the processor 102 can also communicate with neighboring node devices over a network interface.

The memory 101 is configured to store a program, an instruction, or a code;

The processor 102 is configured to execute a program, an instruction, or a code in the memory 102, complete the operations of S301 to S303 in the first embodiment, or complete the operations of S601 to S602 in the second embodiment.

The memory may be, but not limited to, a random access memory (RAM), a read only memory (ROM), an erasable programmable read only memory (EPROM), a compact disk read only memory (CD-ROM), a hard disk, or a magnetic disk. And other media that can store program instruction code.

The processor may be one or more CPUs. In the case of one CPU, the CPU may be a single core CPU or a multi-core CPU.

The present invention further provides a communication system including a first node, a second node, and a network protection device, and the network protection device may be the network protection device shown in Embodiment 3 or Embodiment 4. The network protection device is configured to perform the network protection method according to

Embodiment

1 or 2 of the present application.

The various parts of the specification are described in a progressive manner, and the same or similar parts between the various embodiments may be referred to each other, and each embodiment focuses on differences from other embodiments. In particular, for device and system embodiments, the description is relatively simple as it is substantially similar to the method embodiment, and the relevant portions can be found in the description of the method embodiments.

Finally, it should be noted that the above description is only a preferred embodiment of the technical solution of the present invention. It is not intended to limit the scope of the invention. It will be apparent that those skilled in the art can make various modifications and variations to the present invention without departing from the scope of the invention. All such modifications, equivalents, improvements, etc., are intended to be included within the scope of the present invention.

Claims

A network protection method, comprising:

When a working path of communication between the first node of the ring network and the second node adjacent to the first node occurs a bidirectional signal failure SF, causing the transmission path of the service traffic to be switched from the working path to the protection path, if On the working path, a third node to a fourth node adjacent to the third node generates SF or signal degradation SD, and on the working path, from the second node to the first node When the SF is removed, the first node does not receive the ring network automatic protection switching APS packet sent by the second node from the working path, and determines that the first node to the working path The SF in the direction of the second node is not eliminated, and the service traffic is kept transmitted through the protection path;

The service traffic is transmitted through the first node, the second node, the third node, and the fourth node on the working path.
The method according to claim 1, wherein said maintaining said traffic flow through said protection path comprises: transmitting, at said first node, said second node not received from said working path When the APS packet is sent, the state machine switching state of the first node remains unchanged.
The method according to claim 2, wherein the state machine switching state of the first node remains unchanged, including: the first node does not respond to the switching request sent by the fourth node, and the fourth The switching request sent by the node has a higher priority than the state priority of the first node.
A network protection method, the method comprising:

When the working path communicated between the first node and the second node adjacent to the first node generates a bidirectional signal degradation SD, a bidirectional signal failure occurs in a protection path between the first node and the second node. SF, when traffic is transmitted on the working path; if the SF on the protection path from the second node to the first node is eliminated, and the first node is not received from the protection path The linear automatic protection switching APS packet sent by the second node determines that the SF in the protection path and the direction from the first node to the second node is not eliminated, and the SF is maintained. The traffic is transmitted through the working path.
The method according to claim 4, further comprising: when the first node receives the APS message sent by the second node from the protection path, the first node follows The indication of the APS packet performs protection switching.
A network protection device, comprising: a detecting unit and a service protection unit, wherein

When a working path of communication between the first node of the ring network and the second node adjacent to the first node occurs a bidirectional signal failure SF, causing the transmission path of the service traffic to be switched from the working path to the protection path, if On the working path, the third node to the fourth node adjacent to the third node generates SF or signal degradation SD, and the detecting unit determines that the working path is the second node to the first SF elimination in a node direction, the service protection unit determines that the first node does not receive the ring network automatic protection switching APS message sent by the second node from the working path, and the service protection unit determines The SF of the working path, the direction from the first node to the second node is not eliminated, and the service traffic is kept transmitted through the protection path;

The service traffic is transmitted through the first node, the second node, the third node, and the fourth node on the working path.
The apparatus of claim 6 wherein said apparatus is located on said first node side.
The device according to claim 6 or 7, wherein the service protection unit is further configured to: when the first node receives the APS packet sent by the second node from the working path And instructing the first node to perform protection switching according to the indication of the APS packet.
The device according to any one of claims 6-8, wherein the service protection unit is further configured to: when the first node does not receive the location sent by the second node from the working path When the APS packet is described, the first node is instructed not to respond to the switching request sent by the fourth node, and the switching request sent by the fourth node has a higher priority than the first node.
A network protection device, comprising: a detection unit and a service protection unit, in,

When the working path communicated between the first node and the second node adjacent to the first node generates a bidirectional signal degradation SD, a bidirectional signal failure occurs in a protection path between the first node and the second node. SF, when the service traffic is transmitted in the working path, if the detecting unit determines that the SF is removed from the second node to the first node in the protection path, and the service protection unit determines If the first node does not receive the linear automatic protection switching APS packet sent by the second node from the protection path, the service protection unit determines the first node to the second in the protection path. The SF in the node direction is not eliminated, and the traffic is kept transmitted through the working path.
The apparatus according to claim 10, wherein said apparatus is located on said first node side.
The device according to claim 10 or 11, wherein the service protection unit is further configured to: when the first node receives the APS message sent by the second node from the protection path Instructing the first node to perform protection switching according to the indication of the APS packet.
A communication system comprising a first node, a second node, and the network protection device of any of claims 6-12.