CN100421387C - A business flow protection method - Google Patents

Abstract

The invention discloses a service flow protection method. The forward path between two nodes transmitting the service flow adopts a 1:1 protection group, and a reverse path protection group is set between the two nodes transmitting the service flow. The method comprises the following steps: A, the service flow outlet node judges whether the forward path has a defect according to the connectivity detection result, if there is a defect in the forward path, then executes the protection switching of the node, and the service flow outlet node generates a BDI message , and send the BDI message to the service flow ingress node through the set reverse path protection group; B. The service flow ingress node performs protection switching of the node after receiving the BDI message. The service flow protection method proposed by the invention achieves the purpose of simultaneously protecting the service flow and the BDI message.

Description

A business flow protection method

technical field

The invention relates to a service flow protection technology, in particular to a service flow and protocol message protection method on a Multi-Protocol Label Switching (MPLS, Multi-Protocol Label Switching) network.

Background technique

Currently, on the label switching path (LSP, Label Switching Path) in the MPLS network, the operation and maintenance (OAM, Operations and Maintenance) and protection switching (PS, Protection Switching) protocols are usually run to perform LSP connectivity detection, fault transmission and protection switching. In order to realize the protection of business flow.

FIG. 1 is a structural diagram of an MPLS network device running OAM and PS protocols. The MPLS network device running OAM and PS protocols consists of a management plane 101 , a control plane 102 and a data plane 103 . Among them, the control plane 102 mainly completes call control, connection control, and protocol processing such as routing and signaling required to support these connections; the management plane 101, as a supplement to the control plane 102, completes the maintenance of the entire system and is responsible for all inter-plane communication Coordinate and cooperate to be able to configure and manage end-to-end connectivity. The MPLS OAM module 111 and the MPLS PS module 112 located at the control plane 102 run on the MPLS layer, and the MPLS OAM module 111 is used to detect the state of a specific LSP. When a defect is detected, an alarm will be reported and the MPLS PS module 112 will be notified. Perform protection switching.

In an MPLS network, the principle of running OAM and PS protocols on the forward path using a 1:1 protection group for service flow protection is: the ingress of the forward path periodically generates connectivity packets and passes through the forward path Send it to the egress end of the forward path; the egress end of the forward path periodically detects and reads the connectivity message, and judges whether a defect occurs on the forward path according to the defect standard stipulated in the protocol. If there is a defect on the forward path, the exit end of the forward path performs forward path protection switching, and generates a backward defect indication (BDI, Backward Defect Indication) message, and transmits the BDI message to the entrance of the forward path through the reverse path port; the ingress port of the forward path detects and reads the BDI message and performs forward path protection switching. In this application, the forward direction refers to the flow direction of the service flow, and the reverse direction refers to the flow direction opposite to the direction of the service flow. The forward path adopts a 1:1 protection group, including the forward main path and the forward backup path.

Fig. 2 is a structural diagram of a service flow protection system in the prior art. In Figure 2, the forward service flow flows from service node A as the entry port to service node B as the exit port. There are two forward paths connected between service node A and service node B, and these two forward paths form a 1:1 protection group , including: the forward primary path as the forward working path, represented by a thick solid line in Figure 2; the forward backup path as a forward protection path, represented by a thin solid line in Figure 2, under normal circumstances, the business flow Transmitted from the forward primary path. In Fig. 2, the reverse BDI message flows from service node B to service node A, and only a single reverse path is connected between service node A and service node B.

A service flow protection system in the prior art includes: a service node A protection system 201 and a service node B protection system 202 . The service node A protection system 201 includes: an OAM_A module 213 and a PS_A module 214, the OAM_A module 213 is used to generate and send a connectivity message, detect and process a BDI message, and notify the PS_A module 214 to perform protection switching; the PS_A module 214 is used to perform Forward path protection switching at service node A, saving the working state information of the forward path. The service node B protection system 202 includes: an OAM_B module 225 and a PS_B module 226, the OAM_B module 225 is used to generate and send a BDI message, detect and process a connectivity message, and notify the PS_B module 226 to perform protection switching; the PS_B module 226 is used to perform Forward path protection switching at the service node B, saving the working state information of the forward path.

FIG. 3 is a flow chart of a service flow protection method in the prior art. The service flow protection method in the prior art includes the following steps:

Steps 301-303: the service flow is transmitted from the forward primary path; the OAM_A module 213 generates a connectivity packet and sends the connectivity packet on the forward primary path; the OAM_B module 225 detects the connectivity packet, if detected Connectivity message, then execute step 304, if not detect the connectivity message, then execute step 305 and subsequent steps thereof;

Step 304: The OAM_B module 225 reads the connectivity message and compares it with the defect standard to determine whether there is a defect in the forward active path. If the defect standard is met, it means that the forward active path has a defect, then execute step 305 and its subsequent steps steps, otherwise end the process;

Steps 305-307: OAM_B module 225 notifies PS_B module 226 to switch the service flow to the forward backup path; OAM_B module 225 generates a BDI message, encapsulates the reverse path label before the BDI message and sends it on the reverse path; OAM_A Module 213 detects a BDI message, if a BDI message is detected, step 308 and its subsequent steps are performed, if a BDI message is not detected, the process ends;

Steps 308-311: OAM_A module 213 reads the path label before the BDI message; OAM_A module 213 reads the BDI message; OAM_A module 213 notifies PS_A module 214 to switch the service flow to the forward standby path; Transmitting to the backup path, end this process.

In practical application, the service flow protection method of the prior art is adopted. In the service flow protection system, only the forward path adopts the protection group. When the forward working path fails, the service flow export port performs forward path protection switching to switch the service flow. to the forward protection path, and transmit BDI packets through the single-path reverse path to notify the service flow ingress to switch paths. However, since the reverse path has no protection group, once the reverse path fails, the service flow ingress will If the BDI message cannot be detected, the forward path protection switching cannot be performed to switch the service flow to the forward protection path, and the state of the service flow at the ingress port and the egress port are inconsistent, resulting in interruption of the service flow.

Contents of the invention

In view of this, the main purpose of the present invention is to provide a service flow protection method capable of simultaneously protecting service flows and BDI messages.

In order to achieve the above object, the present invention provides a service flow protection method. The forward path between two nodes transmitting service flows adopts a 1:1 protection group, and a reverse path is set between the two nodes transmitting service flows. To a path protection group, the reverse path protection group is a 1+1 protection group, including a reverse working path and a reverse protection path, the method includes the following steps:

A. The service outflow egress node judges whether there is a defect in the forward path according to the connectivity detection result. If there is a defect in the forward path, it executes the protection switching of the node, and the service outflow egress node generates a BDI message, before the BDI message Encapsulating the reverse working path label and sending the BDI message on the reverse working path, encapsulating the reverse protection path label before the BDI message and sending the BDI message on the reverse protection path;

B. The service flow ingress node detects the BDI message. If a BDI message is detected, step C is performed. If no BDI message is detected, the process ends;

C. The service flow entrance reads the path label of a currently detected BDI message, learns the stolen path of the BDI message, and queries the working status of the reverse path protection group to learn the current reverse working path;

D. The service flow entry-end node judges whether the BDI message described in step C is from the reverse working path, if it is from the reverse working path, then execute step F, if not from the reverse working path, then execute step E;

E. The service flow entry-end node discards the BDI message described in step C; the service flow entry-end node reads the path label before another BDI message, and reads another BDI message, and executes step G;

F. The service flow entrance reads the BDI message described in step C, and executes step G;

G. After receiving the BDI message, the ingress and end nodes of the service flow perform protection switching of the node.

Wherein, the service flow outlet node described in step A judges whether there is a defect in the forward path according to the connectivity detection result, specifically includes:

A11. The service flow ingress node generates a connectivity message and sends the connectivity message on the forward working path;

A12. The service flow egress node detects the connectivity message. If the connectivity message is detected, step A13 is performed. If the connectivity message is not detected, the forward path has a defect;

A13. The service outflow egress node reads the connectivity message and compares it with the defect standard. If the defect standard is met, there is a defect in the forward path; otherwise, there is no defect in the forward path.

A service flow protection method, the forward path between two nodes transmitting and stealing a service flow adopts a 1:1 protection group, and a reverse path protection group is set between the two nodes transmitting the service flow, and the reverse path The path protection group is a 1:1 protection group, including a reverse working path and a reverse protection path, and the method includes the following steps:

A. The service flow egress node judges whether the forward path is defective according to the connectivity detection result. If there is a defect in the forward path, the protection switching of the node is executed, and the service flow exit node generates a BDI message and queries the reverse path. The working status of the protection group, knowing the current reverse working path, encapsulating the reverse working path label before the BDI message and sending the BDI message on the reverse working path;

B. The service flow entry-end node detects the BDI message, and if the BDI message is detected, step C is performed; if the BDI message is not detected, the process is ended;

C. The service flow entry-end node reads the path label of the detected BDI message, and reads the BDI message;

D. After receiving the BDI message, the ingress node of the service flow performs protection switching of the node.

The business outflow egress node in step A determines whether there is a defect in the forward path according to the connectivity detection result, specifically including:

A11. The service flow ingress node generates a connectivity message and sends the connectivity message on the forward working path;

A12. The service flow egress node detects the connectivity message. If the connectivity message is detected, step A13 is performed. If the connectivity message is not detected, the forward path has a defect;

A13. The service outflow egress node reads the connectivity message and compares it with the defect standard. If the defect standard is met, there is a defect in the forward path; otherwise, there is no defect in the forward path.

In the service flow protection method proposed by the present invention, both the forward path and the reverse path in the service flow protection system adopt protection groups. On the forward protection path, the BDI message is transmitted through the reverse path to notify the service flow ingress to switch paths. Since the protection group is set on the reverse path, once the reverse working path fails, the BDI message can still be protected from the reverse path. The ingress port of the service flow can still detect and receive BDI packets, and it can also perform forward path protection switching to switch the service flow to the forward protection path, so that the state of the ingress end of the service flow is consistent with that of the egress end, and the service The flow is uploaded through the forward protection path, achieving the purpose of simultaneously protecting the service flow and the BDI message.

Description of drawings

Fig. 1 is the structure diagram of the MPLS network equipment of operation OAM and PS agreement;

FIG. 2 is a structural diagram of a service flow protection system in the prior art;

FIG. 3 is a flowchart of a service flow protection method in the prior art;

FIG. 4 is a structural diagram of a service flow protection system according to Embodiment 1 of the present invention;

FIG. 5 is a flowchart of a service flow protection method according to Embodiment 1 of the present invention;

FIG. 6 is a structural diagram of a service flow protection system according to Embodiment 2 of the present invention;

FIG. 7 is a flowchart of a service flow protection method according to Embodiment 2 of the present invention.

Detailed ways

The core idea of the present invention is: by setting a protection group for the reverse path in the service flow protection system, the forward service flow and the reverse BDI message are simultaneously protected. Here, the set protection group may be a 1+1 protection group or a 1:1 protection group.

In order to make the object, technical solution and advantages of the present invention clearer, the following examples are given and the present invention is further described in detail with reference to the accompanying drawings.

Embodiment one:

Figure 4 is a structural diagram of the service flow protection system in Embodiment 1 of the present invention. There are two reverse paths connected between service node A and service node B in this embodiment, and these two reverse paths form a 1+1 protection group , including: a reverse primary path as a reverse working path, represented by a thick solid line in FIG. 4 ; and a reverse backup path as a reverse protection path, represented by a thin solid line in FIG. 4 . Normally, BDI packets are transmitted over the reverse primary path and the reverse backup path at the same time.

The service flow protection system in this embodiment includes: a service node A protection system 201 and a service node B protection system 202, where service node A is a service flow entry port, and service node B is a service flow exit port. The service node A protection system includes: OAM_A module 213, PS_A module 214 and PS_A_R module 414, PS_A_R module 414 is used to perform reverse path protection switching at service node A and save the working state information of the reverse path; OAM_A module 213 also uses To query the PS_A_R module 414 for the working state information of the reverse path. The service node B protection system includes: OAM_B module 225 and PS_B module 226 .

FIG. 5 is a flowchart of a service flow protection method in Embodiment 1 of the present invention. The service flow protection method in this embodiment includes the following steps:

Steps 501-503: the service flow is transmitted from the forward primary path; the OAM_A module 213 generates a connectivity packet and sends the connectivity packet on the forward primary path; the OAM_B module 225 detects the connectivity packet, such as detecting To the connectivity message, then perform step 504, as not detect the connectivity message, then perform step 505 and its subsequent steps;

Step 504: The OAM_B module 225 reads the connectivity message and compares it with the defect standard to determine whether the forward active path is defective. If the forward active path is defective, execute step 505 and its subsequent steps, otherwise end this chapter. process;

Steps 505-507: the OAM_B module 225 notifies the PS_B module 226 to switch the service flow to the forward backup path; the OAM_B module 225 generates a BDI message, encapsulates the reverse active path label before the BDI message, and sends the label on the reverse active path Send the BDI message on the Internet, encapsulate the reverse backup path label before the BDI message and send the BDI message on the reverse backup path; the OAM_A module 213 detects the BDI message, and if a BDI message is detected, then execute step 508 And its subsequent steps, if no BDI message is detected, then end this process;

Steps 508-509: the OAM_A module 213 reads the path label of a BDI message to know its transmission path; the OAM_A module 213 inquires the PS_A_R module 414 about the working status of the reverse path, and judges the reverse path according to the corresponding relationship between the transmission path and the working state. Whether the BDI message is from the reverse working path, if the BDI message is from the reverse working path, then perform step 513, if the BDI message is not from the reverse working path, then perform step 510 and its subsequent steps;

Steps 510-512: the OAM_A module 213 discards the BDI message; the OAM_A module 213 reads the path label before another BDI message, reads another BDI message, and executes step 514 and its subsequent steps;

Step 513: OAM_A module 213 reads the BDI message, and executes step 514 and its subsequent steps;

Steps 514-515: the OAM_A module 213 notifies the PS_A module 214 to switch the service flow to the forward standby path; the service flow is transmitted on the forward standby path, and this process ends.

Since the reverse path adopts a 1+1 protection group, the OAM_B module 225 sends a BDI message on the reverse working path and the reverse protection path at the same time, then in the step 507, the OAM_A module 213 may simultaneously detect two To the BDI message of the working path and the reverse protection path, then perform steps 508 and 509 to read the path label of one of the BDI messages first, and judge whether the read BDI message comes from the reverse working path, such as the BDI If the message is from the reverse working path, execute step 513 to read the BDI message; if the BDI message does not come from the reverse working path, then perform steps 510 to 512 to discard the BDI message and read another BDI message. The other BDI message read at this time is a message from the reverse working path.

In the step 508, after the OAM_A module 213 reads the path label of one of the BDI messages, it can also directly execute the step 513 to read the BDI message.

Embodiment two:

Fig. 6 is the structural diagram of the service flow protection system of the second embodiment of the present invention. There are two reverse paths connected between the service node A and the service node B in this embodiment, and these two reverse paths form a 1:1 protection group , including: a reverse primary path as a reverse working path, represented by a thick solid line in FIG. 6 ; and a reverse backup path as a reverse protection path, represented by a thin solid line in FIG. 6 . Normally, BDI packets are transmitted on the reverse primary path.

The service flow protection system in this embodiment includes: a service node A protection system 201 and a service node B protection system 202, where service node A is a service flow entry port, and service node B is a service flow exit port. Service node A protection system includes: OAM_A module 213, PS_A module 214 and PS_A_R module 414; service node B protection system includes: OAM_B module 225, PS_B module 226 and PS_B_R module 626, PS_B_R module 626 is used to execute the anti- switch to path protection and save the working state information of the reverse path; the OAM_B module 225 is also used to query the PS_B_R module 626 for the working state information of the reverse path.

FIG. 7 is a flowchart of a service flow protection method in Embodiment 2 of the present invention. The service flow protection method in this embodiment includes the following steps:

Steps 701-703: the service flow is transmitted from the forward primary path; the OAM_A module 213 generates a connectivity packet and sends the connectivity packet on the forward primary path; the OAM_B module 225 detects the connectivity packet, such as detecting If the connectivity message is detected, step 704 is performed, and if the connectivity message is not detected, step 705 and subsequent steps thereof are performed;

Step 704: The OAM_B module 225 reads the connectivity message and compares it with the defect standard to determine whether the forward active path is defective. If the forward active path is defective, execute step 705 and its subsequent steps, otherwise end this chapter. process;

Steps 705-706: the OAM_B module 225 notifies the PS_B module 226 to switch the service flow to the forward backup path; the OAM_B module 225 generates a BDI message, and queries the PS_B_R module 626 about the working status of the reverse path to determine whether the reverse primary path is For the reverse working path, if the reverse active path is the reverse working path, then perform step 707; if the reverse active path is not the reverse working path, then perform step 708;

Step 707: The OAM_B module 225 encapsulates the reverse active path label before the BDI message and sends the BDI message on the reverse active path, and executes step 709;

Step 708: The OAM_B module 225 encapsulates the reverse backup path label before the BDI message and sends the BDI message on the reverse backup path, and executes step 709;

Step 709: OAM_A module 213 detects the BDI message, if a BDI message is detected, then execute step 710 and its subsequent steps, if no BDI message is detected, then end this process;

Steps 710-713: OAM_A module 213 reads the path label before the BDI message; OAM_A module 213 reads the BDI message; OAM_A module 213 notifies PS_A module 214 to switch the service flow to the forward standby path; Transmitting to the backup path, end this process.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention.

Claims (4)

1. A service flow protection method, the forward path between two nodes of the transmission service flow adopts a 1:1 protection group, and it is characterized in that reverse path protection is set between the two nodes of the transmission service flow group, the reverse path protection group is a 1+1 protection group, including a reverse working path and a reverse protection path, the method includes the following steps: A. The service outflow egress node judges whether there is a defect in the forward path according to the connectivity detection result. If there is a defect in the forward path, it executes the protection switching of the node, and the service outflow egress node generates a BDI message, before the BDI message Encapsulating the reverse working path label and sending the BDI message on the reverse working path, encapsulating the reverse protection path label before the BDI message and sending the BDI message on the reverse protection path; B. The service flow ingress node detects the BDI message. If a BDI message is detected, step C is performed. If no BDI message is detected, the process ends; C. The service flow entrance reads the path label of a currently detected BDI message, learns the stolen path of the BDI message, and queries the working status of the reverse path protection group to learn the current reverse working path; D. The service flow entry-end node judges whether the BDI message described in step C is from the reverse working path, if it is from the reverse working path, then execute step F, if not from the reverse working path, then execute step E; E. The service flow entry-end node discards the BDI message described in step C; the service flow entry-end node reads the path label before another BDI message, and reads another BDI message, and executes step G; F. The service flow entrance reads the BDI message described in step C, and executes step G; G. After receiving the BDI message, the ingress and end nodes of the service flow perform protection switching of the node. 2. The business flow protection method according to claim 1, wherein the business flow egress node in step A judges whether there is a defect in the forward path according to the connectivity detection result, specifically comprising: A11. The service flow ingress node generates a connectivity message and sends the connectivity message on the forward working path; A12. The service flow egress node detects the connectivity message. If the connectivity message is detected, step A13 is performed. If the connectivity message is not detected, the forward path has a defect; A13. The service outflow egress node reads the connectivity message and compares it with the defect standard. If the defect standard is met, there is a defect in the forward path; otherwise, there is no defect in the forward path. 3. A service flow protection method, the forward path between the two nodes of the stolen service flow adopts a 1:1 protection group, and it is characterized in that a reverse path is set between the two nodes of the transmission service flow A protection group, the reverse path protection group is a 1:1 protection group, including a reverse working path and a reverse protection path, and the method includes the following steps: A. The service flow egress node judges whether the forward path is defective according to the connectivity detection result. If there is a defect in the forward path, the protection switching of the node is executed, and the service flow exit node generates a BDI message and queries the reverse path. The working status of the protection group, knowing the current reverse working path, encapsulating the reverse working path label before the BDI message and sending the BDI message on the reverse working path; B. The service flow entry-end node detects the BDI message, and if the BDI message is detected, step C is performed; if the BDI message is not detected, the process is ended; C. The service flow entry-end node reads the path label of the detected BDI message, and reads the BDI message; D. After receiving the BDI message, the ingress node of the service flow performs protection switching of the node. 4. The business flow protection method according to claim 3, wherein the business flow egress node in step A judges whether there is a defect in the forward path according to the connectivity detection result, specifically comprising: A11. The service flow ingress node generates a connectivity message and sends the connectivity message on the forward working path; A12. The service flow egress node detects the connectivity message. If the connectivity message is detected, step A13 is performed. If the connectivity message is not detected, the forward path has a defect; A13. The service outflow egress node reads the connectivity message and compares it with the defect standard. If the defect standard is met, there is a defect in the forward path; otherwise, there is no defect in the forward path.

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