CN1984039A - Fast re-routing method for shared multi-port transmitting link - Google Patents

Abstract

The present invention is applicable to the field of communication transmission, and discloses a fast rerouting method when multiple ports share a transmission link. The method includes: bundling multiple ports sharing the same transmission link in a terminal to form a bundled port; Select an active port among the bundled ports to send and receive messages; perform fault detection on the transmission link; select a backup port to send and receive messages when a link failure is detected. The invention can solve the problem of backup protection when there is only one transmission ring network between two communication devices, and satisfies the real-time service requirements of users.

Description

A fast rerouting method when multiple ports share the transmission link

technical field

The invention relates to the field of communication transmission, in particular to a method for realizing fast rerouting when a plurality of ports share a transmission link.

Background technique

With the development of network technology, users have increasingly higher requirements for network reliability. Current networking solutions generally provide multi-link protection. When a link fails, fast rerouting technology is used to implement service switching to ensure Continuity of User Communications.

BFD (Bidirectional Forwarding Detection) is a mechanism used to detect the availability of a forwarding path between a pair of forwarding engines, which provides a low-overhead, short detection period (less than 50ms) failure between two adjacent systems Detection mechanism, including detection of interface, data link and forwarding engine itself.

FIG. 1 shows a fast rerouting protection scheme for independent backup links in the prior art.

In Fig. 1, there are two communication links between R1 as the sending end and the destination network, from R1 to the destination network through R2 and from R1 to the destination network through R3. Select one of the links (such as R1-R2-destination network in the figure) to be the active link for message transmission:

Step 11 shows that the active link fails, and packet transmission is interrupted;

Shown in step 12 is to utilize the fast rerouting technology to carry out fast switching, and the backup link (R1-R3-purpose network) enters the working state;

Step 13 shows that the failure of the active link is recovered, and the active link is reselected for packet transmission.

The advantage of this solution is that the detection method is simple, and fast service switching can be realized at any time, which meets the real-time service needs of users; the disadvantage is that the cost of renting multiple transmission links is too high in the case of long transmission paths Economic requirements.

Fig. 2 shows a networking solution using a transmission ring network in the prior art.

The terminal devices R1 and R2 are respectively connected to the transmission ring network through the transmission device. There are still backup links Port1 and Port2 between the terminal device and the transmission device, but only one transmission ring network is leased between the two transmission devices to send messages. In this way, there are no two independent links between the terminal devices R1 and R2, and the message sent from any port of R1 will be transmitted to the terminal device R2 through Port1 and Port2 through the transmission device B at the same time.

The advantage of this solution is that when the traffic is transmitted, the protection mechanism of the transmission ring network itself is used, so that only one transmission ring can be rented to realize the barrier-free transmission of the message, which saves costs; the disadvantage is that the terminal equipment must pass The transmission device is connected to the transmission ring network. Although there is a backup link between the terminal device and the transmission device, it cannot solve the link negotiation problem at the receiving end.

Contents of the invention

The purpose of the present invention is to solve the problem of backup protection when the message is transmitted through the transmission ring network in the prior art, realize fast rerouting and fast switching when the link fails, meet the real-time business needs of the user, and save the operating cost of the service provider at the same time .

In order to achieve the purpose of the invention, the present invention provides a fast rerouting method when a plurality of ports share a transmission link, said method comprising the following steps:

Bind multiple ports sharing the same transmission link to a terminal device to form a bundled port;

Select an active port to send and receive messages among the bundled ports of the terminal device;

Fault detection on the transmission link;

When a link failure is detected, a standby port is selected for sending and receiving packets.

In addition, the terminal in the present invention includes a sending terminal and a receiving terminal.

The method of the present invention further includes: the bundled port provides a logical bundled interface to the upper layer protocol, and an IP address and a routing protocol are configured on the bundled interface, thereby avoiding the upper layer protocol (such as a routing protocol) etc. A state change occurred.

The main port described in the method of the present invention can be manually set, and can also be configured through an algorithm, and the information for setting the main port is configured on the corresponding binding interface.

The method of the present invention further includes: the default message is transmitted from the main port.

After the fault detection is carried out to the link in the method of the present invention, if:

If the active link is not faulty, the active port continues to transmit packets;

If the active link fails, the traffic will be switched to the standby link for transmission by fast rerouting method.

In the method of the present invention, the active link is the link between the active port and the transmission device.

In addition, in the method of the present invention, if all port links fail, the transmitted message can be discarded or processed by any port.

The method of the present invention further includes, after the failure of the main port link is restored, the following method can be used to re-transmit and send messages:

switch traffic to the original primary port; or

Use the selected backup port as the new active port to continue sending and receiving packets until the next link failure, and the restored original active port exists as the backup port.

Another feature of the method is that the link detection and message sending and receiving are performed synchronously, and the detection mechanism detects the ports according to a certain period, and configures the fault information on the ports corresponding to the links.

The method further includes realizing that only one of the multiple ports of the bundled port is in a communication state at any time through link negotiation; and the time for traffic switching should be after the link negotiation is completed.

It can be seen from the above-mentioned technical solution provided by the present invention that the present invention implements a fast rerouting implementation method when multiple ports share a transmission link, effectively improves the reliability of information transmission, and satisfies the real-time service requirements of users.

Description of drawings

Fig. 1 is the fast rerouting implementation scheme of the independent backup link in the prior art;

Fig. 2 is a networking scheme using a single transmission ring network in the prior art;

FIG. 3 is an improved technical solution proposed for the prior art in an embodiment of the present invention;

Fig. 4 is a flow chart of the present invention to realize the fast rerouting protection when the transmission link is shared through the detection mechanism.

Detailed ways

The core idea of the present invention is: under the condition that only one transmission ring network is used for message transmission, multiple ports and backup links are set between the terminal equipment and the transmission equipment connected to it, and the multiple ports are bundled to form a Bind ports and share a transmission link. Perform link detection on multiple link configuration detection mechanisms between the terminal device and the transmission device, and use fast rerouting technology to perform port switching when a link failure occurs, so as to meet the real-time business needs of users and save service providers for the purpose of operating costs.

In order to make the purpose, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

Figure 3 shows a schematic diagram of the networking scheme of an embodiment of the technical method provided by the present invention, that is, absorbing the reasonable components in the prior art 1, setting up a backup link between the transmission device and the terminal device, and configuring the BFD protocol for linking Road detection:

The sending terminal R1 selects Port1 as the primary link for packet transmission, and configures the BFD protocol to perform link detection between the sending terminal R1 and the transmission device A;

The BFD protocol detects that the Port1 link is faulty, and uses the fast rerouting technology to switch to the Port2 link to send packets;

The communication capability of the Port1 link is restored, and the transmission is switched to the Port1 link again.

After the message arrives at the receiving terminal transmission device B through the transmission ring network, the message is sent out from the links corresponding to Port3 and Port4 at the same time;

The message arrives at the receiving terminal R2, and R2 receives the message from the configured primary port Port3 by default;

BFD detects that the active port Port3 is faulty, and selects the standby port Port4 to receive packets.

In order not to lose user data packets during port switching, set a storage module at the entrance of multiple ports on the receiving end, and set the buffering time to be greater than or equal to the time when BFD detects a fault and completes the switching.

Fig. 4 is the detailed flowchart of the fast rerouting protection when the present invention realizes shared transmission link through detection mechanism, and the steps described in Fig. 4 can all be realized on the network described in Fig. 3, specifically comprise the following steps:

Step 401, the message sent by the sending end R1 arrives at the logical binding interface of the binding port;

Step 402, the binding interface selects the primary sending port according to the pre-set primary port selection rules;

Step 403, according to the detection result information configured on the active port, it is judged whether the link of the active port fails, if there is no fault, execute step 404, if there is a fault, go to step 405;

Step 404, the main port is used to send messages;

Step 405 reselects a port as the active port;

Step 406, judging whether the newly selected primary port link fails, if no failure occurs, execute step 404, if a fault occurs, execute step 407;

Step 407, judging whether all port links have failed, if there is a link that does not fail, execute step 405, if all port links fail, then execute step 408;

Step 408, discarding the message being sent, or selecting the port where the current message is located, or selecting any port to send the message;

Step 409, the successfully sent message reaches the binding interface of the receiving end through the transmission ring network;

Step 410, the binding interface selects the main receiving port according to the pre-set main port selection rule;

Step 411, judging whether the main receiving port link is faulty, if faulty, then execute step 413, if no fault occurs, then execute step 412;

Step 412, the main receiving port receives the message;

Step 413, reselecting the main receiving port;

Step 414, judging whether the newly selected active receiving port link is faulty, if a fault occurs, execute step 415, and if no fault occurs, execute step 412;

Step 415, judging whether all the receiving port links fail, if all the port links fail, then execute step 416, if any port link does not fail, then execute step 413;

Step 416, discarding the message arriving at the receiving port or selecting the current port or any port to receive the message. .

In the above process, before the message starts to be transmitted, multiple ports should be bundled at the sending end and the receiving end to form a bundled port, provide a logical bundled interface for the upper layer protocol, and configure the IP address and routing protocol, so as to avoid The state of the upper layer protocol changes when the port is switched. Similarly, certain rules should be established for the selection of the primary port before packet transmission to avoid confusion during packet transmission. This configuration can be done manually or by using a certain algorithm. Port information is configured on the corresponding bonded interface.

While sending and receiving messages, the detection mechanism configured between the terminal device and the transmission device periodically detects the link without interruption, and configures the fault information on the port corresponding to the link.

It should be noted that although the present invention only enumerates the situation where two ports share the same transmission link, this is only for the convenience of explaining the problem, and all other situations in which a plurality of ports share the same transmission link all belong to the concept scope of the present invention . In the case of multiple links coexisting, the detection mechanism may discard the message or select a port for transmission only when all the backup links are detected and all backup links fail. Here, two Cases:

After detecting that all ports are faulty, immediately discard the message or select any port to transmit the message; or

After all links are detected to be faulty, go back and re-detect the active link. Only when the active link is still faulty in the secondary detection, the packet is discarded or a port is randomly selected to transmit the packet.

Another purpose of the present invention is to avoid transmission confusion between multiple ports of the sending end or the receiving end, so it is necessary to limit the multiple ports of the bundled port to be determined only by a certain protocol at any time. Packet transmission, while other ports are in waiting or idle state.

In the present invention, it should also be explained that, in order to prevent the loss of data packets, the link switching should be performed after the corresponding link negotiation is completed.

The above-mentioned use of BFD for session link detection is only a preferred embodiment of the present invention, and is not used to limit the scope of the present invention. All methods that can realize link detection belong to the idea of the present invention. Any modifications, substitutions and improvements equivalent in spirit and principle shall be included within the protection scope of the present invention.

Claims (13)

1. A fast rerouting method when a plurality of ports share a transmission link, wherein the method comprises: Bind multiple ports sharing the same transmission link to a terminal device to form a bundled port; Select an active port to send and receive messages among the bundled ports of the terminal device; Fault detection on the transmission link; If the link of the active port fails, select the standby port to send and receive packets. 2. The method according to claim 1, wherein the terminal comprises a sending terminal and a receiving terminal. 3. The method according to claim 1, wherein the binding port provides a logical binding interface to the upper layer protocol. 4. The method according to claim 3, wherein an IP address and a routing protocol are configured on the binding interface. 5. The method according to claim 1, wherein the main port can be manually set, or can be configured through an algorithm, and the information for setting the main port is configured on the corresponding binding interface. 6. The method according to claim 1, characterized in that, by default, packets are transmitted through the primary port. 7. The method according to claim 1, characterized in that, after fault detection is performed on the transmission link, if: If the active link is not faulty, the active port continues to send and receive packets; If the active link fails, the traffic will be switched to the standby link for transmission. 8. The method according to claim 7, wherein the link detection and message sending and receiving are carried out synchronously, and the detection mechanism detects the link according to a certain period, and configures the fault information on the port corresponding to the link superior. 9. The method according to claim 7, wherein the active link is a link between the active port and the transmission device. 10. The method according to claim 7, characterized in that, if all port links fail, the transmitted message can be discarded or processed by any port. 11. The method according to claim 1, further comprising: after the link failure of the active port is restored, the following method can be used to re-determine the active port: switch traffic to the original primary port; or Use the selected backup port as the new active port to continue sending and receiving packets until the next link failure, and the restored original active port exists as the backup port. 12. The method according to claim 7 or 10, characterized in that the time for traffic switching should be after the link negotiation is completed. 13. The method according to any one of claims 6, 7, 8 or 10, characterized in that only one of the multiple ports of the bundled port is in a communication state at any time.

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