WO2020119644A1

WO2020119644A1 - Forwarding entry generation method, apparatus, and device

Info

Publication number: WO2020119644A1
Application number: PCT/CN2019/124063
Authority: WO
Inventors: 赵科强
Original assignee: 华为技术有限公司
Priority date: 2018-12-10
Filing date: 2019-12-09
Publication date: 2020-06-18
Also published as: CN109617803B; CN109617803A

Abstract

Embodiments of the present application provide a forwarding entry generation method, apparatus, and device for reducing traffic interruption duration and service loss. The forwarding entry generation method comprises: a first node establishing a tunnel to a second node, the first node being a source node of a main path, and the second node being in a network topology from the source node to a destination node of the main path and being a Q node belonging to a Q space, wherein the tunnel does not pass through the main path; and the first node generating a forwarding entry of the first node, the forwarding entry of the first node comprising an outbound interface, and the outbound interface being a tunnel interface of the tunnel, wherein the forwarding entry of the first node is used to forward a packet to the second node when the main path is faulty.

Description

Method, device and equipment for generating forwarding entry

This application requires the priority of the Chinese patent application submitted to the State Intellectual Property Office of China on December 10, 2018, application number 201811504018.X, the application name is "a method, device and equipment for generating forwarding entries", all of its content Incorporated by reference in this application.

Technical field

The present application relates to the field of network communications, and in particular, to a forwarding entry generation method, device, and equipment.

Background technique

When the link or node in the network fails, the packets that pass through these failed nodes to the destination node may be discarded or form a loopback. In this way, transient traffic interruption or traffic loopback will inevitably occur in the network until the network re-converges Calculate the new path. Usually, such an interruption will last for a few seconds or so.

With the expansion of the network scale and the emergence of new applications, some applications are very sensitive to the interruption of traffic, such as real-time services such as IP phones, streaming media, online games and remote video conferencing. In this way, when the node fails, the rapid recovery of traffic becomes particularly important.

In order to reduce the interruption time of traffic in the network, fast reroute (FRR) technology came into being. This technology can calculate one or more backup paths in advance for the main path. When the link or node on the main path fails, the traffic can be quickly switched to the backup path, thereby improving the reliability of the network.

The core step of fast rerouting is to calculate the loop-free backup next hop (LFA) to the destination node for the source node of the main path. If the loop-free backup next hop cannot be calculated, the source node reaches the destination The node's remote loop-free backup next-hop (remote loop free alternative, R-LFA). Then, the backup path is calculated according to the next hop of the source node's ring-free backup or the next hop of the remote ring-free backup.

However, in some scenarios, the next hop of the remote loopless backup of the source node cannot be calculated, and the backup path cannot be calculated. The path from the source node to the destination node can only be re-converged after the failure of the main path in the traditional way , So it will cause traffic interruption and business loss

Summary of the invention

Embodiments of the present application provide a forwarding entry generation method, device, and equipment, which are used to reduce the time of traffic interruption and reduce the loss of services.

In a first aspect, an embodiment of the present application provides a forwarding entry generation method, which can be applied to a first node, and the first node is a source node of a main path. The method includes the following steps: First, the first node establishes a tunnel to the second node. The second node is a Q node that belongs to Q-space in the network topology from the source node to the destination node of the main path. For example, the second node may be the Q node closest or farthest from the first node in Q space. The tunnel does not go through the main path. The type of tunnel is, for example, a resource reservation protocol-resource engineering (reservation protocol-traffic engineering, RSVP-TE) tunnel. Second, the first node generates a forwarding entry of the first node. The forwarding entry of the first node includes an outgoing interface, and the outgoing interface is a tunnel interface of the tunnel. The forwarding entry of the first node is used to send a The node forwards the message. The message may be an internet protocol (IP) message or a multi-protocol label switching (MPLS) message, etc. In the embodiment of the present application, the first node establishes a tunnel to the second node as the Q node, and generates a forwarding entry of the first node according to the tunnel interface of the tunnel, so that the first node can be in the case of a failure of the main path. Switch the traffic to the backup path in time, that is, the first node can timely send the packet to the second node through the tunnel corresponding to the tunnel interface, and the second node sends the packet to the destination node. Compared with the existing solution where the PQ node cannot be calculated, the path from the source node to the destination node can only be re-converged after the failure of the main path, so as to perform packet forwarding, the embodiment of the present application can effectively shorten the traffic switching The time required to reduce business losses. If the first node automatically calculates the Q node as the second node, it can also reduce manual workload and improve the efficiency of generating the forwarding entry of the first node.

In the embodiment of the present application, the forwarding entry of the first node may be a routing entry for forwarding IP packets or a label forwarding entry for forwarding MPLS packets.

If the forwarding entry of the first node is a routing entry, the forwarding entry of the first node also includes a next-hop address, and the next-hop address is an Internet protocol IP address of the second node obtained in advance. The next hop address is the IP address of the second node acquired in advance. The IP address of the second node is used by the first node to look up the address resolution protocol (ARP) table, obtain the media access control (MAC) address, and encapsulate the MAC address in the Ethernet header of the packet .

If the forwarding entry of the first node is a label forwarding entry, the label forwarding entry also includes an output label, and the output label includes a first label and a second label, and the first label is a label from the first node to the second node A distribution protocol (label, distribution, LDP) label, and the second label is a multi-protocol label switching MPLS traffic engineering (TE) label for the tunnel.

In order to obtain the first label, the method further includes: the first node establishing a remote LDP session with the second node to receive the first label sent by the second node.

Optionally, the method further includes: when the main path fails, the first node sends a message to the second node through the tunnel, the inner layer of the message encapsulates the first label, and the outer layer of the message encapsulates the second label.

In a second aspect, an embodiment of the present application also provides a forwarding entry generation device, which is applied to a first node, and the first node is a source node of a primary path. The device includes: a tunnel establishment unit, configured to establish a path to the second node The second node is the Q node in the Q space in the network topology from the source node to the destination node of the main path. The tunnel does not pass through the main path; the entry generation unit is used to generate the forwarding entry of the first node. The forwarding entry of a node includes the outgoing interface, and the outgoing interface is the tunnel interface of the tunnel. The forwarding entry of the first node is used to forward the message to the second node when the main path fails.

Optionally, the forwarding entry of the first node is a routing entry or a label forwarding entry.

Optionally, if the forwarding entry of the first node is a routing entry, the forwarding entry of the first node also includes a next-hop address, and the next-hop address is an Internet protocol IP address of the second node obtained in advance.

Optionally, if the forwarding entry of the first node is a label forwarding entry, the label forwarding entry also includes an output label, and the output label includes a first label and a second label. The first label is from the first node to the first The two-node label distribution protocol LDP label, the second label is the tunnel's multi-protocol label switching traffic engineering MPLS TE label.

Optionally, the device further includes: a session establishment unit, configured to establish a remote LDP session with the second node to receive the first label sent by the second node.

Optionally, the device further includes: a message sending unit, configured to send a message to the second node through the tunnel when the main path fails, the inner layer of the message encapsulates the first label, and the outer layer of the message encapsulates the second label .

Optionally, the second node is the Q node that is closest to or farthest from the first node in Q space.

Optionally, the tunnel is a resource reservation protocol-traffic engineering RSVP-TE tunnel.

Optionally, the message is an IP message or an MPLS message.

In a third aspect, an embodiment of the present application further provides a forwarding entry generation device, where the device is a first node, and the first node includes a storage unit, a processing unit, and a communication unit,

Storage unit for storing instructions;

The processing unit is configured to execute instructions in the memory and execute the foregoing forwarding entry generation method;

The communication unit is used to communicate with the second node.

According to a fourth aspect, an embodiment of the present application further provides a computer-readable storage medium, including instructions that, when run on a computer, cause the computer to execute the foregoing forwarding entry generation method.

BRIEF DESCRIPTION

FIG. 1 is a schematic diagram of a networking provided by an embodiment of this application;

2 is a schematic flowchart of a method for generating a forwarding entry provided by an embodiment of this application;

3 is a schematic diagram of packet forwarding corresponding to the example shown in FIG. 1 provided by an embodiment of the present application;

4 is a structural block diagram of a forwarding entry generation device provided by an embodiment of the present application;

FIG. 5 is a hardware architecture diagram of a forwarding entry generation device provided by an embodiment of the present application.

detailed description

As mentioned above, the core step of fast rerouting technology is to calculate the next hop of the loop-free backup to the destination node or the next hop of the remote loop-free backup for the source node of the main path.

In the embodiment of the present application, the main path is usually one path, and the backup path may have one or more paths. The main path and the backup path are two or more paths starting from the source node. It should be noted that, in the embodiment of the present application, the source node refers to the starting node where the main path and the backup path intersect, and it may or may not be the initial node for packet forwarding. For the source node, the main path and the backup path correspond to different outgoing interfaces. The destination node is the end node where the main path and the backup path intersect. It may or may not be the end node for packet forwarding. Usually there are two forwarding entries in the source node. The forwarding entry corresponding to the main path is used to forward the message to the next hop node of the main path, and the forwarding entry corresponding to the standby path is used to the next hop of the standby path. The node forwards the message. When the main path is normal, the source node uses the forwarding entry corresponding to the main path to forward the message; when the main path fails, the source node uses the forwarding entry corresponding to the standby path to forward the message.

To calculate the backup path, you can first calculate the LFA from the source node to the destination node. The conditions that LFA needs to meet are: cost(N→D)<cost(N→S)+cost(S→D), where S is the source node, D is the destination node, and N is the LFA of the source node, cost(N →D) refers to the link cost of the shortest path from N to D, cost(N→S) refers to the link cost of the shortest path from N to S, and cost(S→D) refers to the shortest path from S to D Link cost.

For example, see Figure 1, which is a schematic diagram of networking. In this network, it includes source node S, destination node D, node A directly connected to source node S and node B directly connected to destination node, where source node S is directly connected to destination node D, node A and node B is directly connected. The main path is the path from the source node S to the destination node D.

The link cost between source node S and destination node D is 10, the link cost between source node S and node A is 10, the link cost between node A and node B is 100, and node B and destination node The link overhead between D is 10. Therefore, the shortest path from the neighbor node A of the source node S to the destination node D is: node A→source node S→destination node D, cost(A→D)=cost(A→S)+cost(S→D)= 20. And cost(A→S)=10,

cost(S→D)=10, so cost(A→D)=cost(A→S)+cost(S→D), the condition of LFA is not satisfied, which means that node A cannot be the LFA of source node S.

If LFA cannot be calculated, R-LFA can be calculated. The method of calculating R-LFA is to calculate the PQ nodes of the network topology from the source node to the destination node. The so-called PQ node refers to a node that belongs to both P space (P-space) and Q space. P-space refers to the set of shortest path trees with the source node as the root node, and all slave root nodes reachable without going through the main path. The Q space refers to the set of reverse shortest path trees with the destination node as the root node, and all slave nodes reachable without going through the main path.

Taking Figure 1 as an example, the P node belonging to the P space includes node A, and the Q node belonging to the Q space includes node B. There is no intersection between the P space and the Q space, so the PQ node cannot be obtained, that is, the R-LFA cannot be calculated.

In this case, the prior art can only follow the traditional way, when the main path from the source node S to the destination node D fails, the path from the source node to the destination node is re-converged to pass the recalculated path Forward the message. This process takes a long time and may cause traffic interruption and business loss.

In order to solve the above technical problems, the embodiments of the present application provide a forwarding entry generation method, device, and equipment, which can still quickly switch to a standby path for packet forwarding when PQ nodes are not calculated, reducing traffic interruption And the purpose of reducing business losses.

The technical solution of the present application will be described in detail below with reference to the drawings.

Referring to FIG. 2, this figure is a schematic flowchart of a method for generating a forwarding entry provided by an embodiment of the present application. The method may be applied to a first node, and the first node may be a source node of a main path, that is, a source of a backup path node. The first node may be a device such as a router, a switch, or a software defined network (SDN) controller.

The forwarding table entry generation method includes the following steps:

S101: The first node establishes a tunnel to the second node.

In the embodiment of the present application, the second node is a Q node belonging to the Q space in the network topology from the source node to the destination node of the main path. Taking Figure 1 as an example, the Q node is Node B. Since the Q node to the destination node does not pass through the main path, the Q node is used as the first node's acyclic backup next hop node, which can ensure that after the main path fails, the source node can report through the backup path through the Q node to the destination node. Forwarding of text.

In practical applications, the Q node may be automatically calculated by the first node, or may be designated. If the Q space includes multiple Q nodes, one Q node can be selected from the multiple Q nodes as the second node. For example, the node closest to the first node or the node farthest from the first node may be selected as the second node from the plurality of Q nodes. Specifically, the first node may calculate the distance between the multiple Q nodes and the first node, and then determine the node that is closest to or farthest from the first node according to the distance between the multiple Q nodes and the first node. The second node. Of course, the selection of the second node may also be based on other rules, which are not specifically limited in the embodiments of the present application.

In the embodiment of the present application, the second node may be a device such as a router, a switch, or a software defined network (software defined network, SDN) controller.

According to the definition of Q space, the second node is a non-neighbor node of the first node, so in order for the second node to be the next hop of the first node's acyclic backup, the first node needs to establish a tunnel to the second node , And the tunnel does not go through the main path, otherwise the backup path will not work when the main path fails. Specifically, the first node excludes the establishment of a tunnel between the protected link and the protected node, the protected link is the outgoing interface of the primary path from the first node to the destination node, and the protected node is the primary path of the primary path from the first node to the destination node Next hop. Taking FIG. 1 as an example, the protected link is the link between the source node S and the destination node D, and the protected node is the destination node D. The source node S establishes a tunnel to node B, which does not go directly through the main path from source node S to node D.

The tunnel may be an RSVP-TE tunnel or other types of tunnels, which are not specifically limited in the embodiments of the present application.

Taking the tunnel as an RSVP-TE tunnel as an example, the process of establishing a tunnel may be that the first node sends a tunnel establishment request to the second node, and the second node sends the tunnel's MPLS TE label to the first node according to the tunnel establishment request. After receiving the MPLS TE label, the first node generates a tunnel interface. The tunnel interface is a logical interface, and it has a mapping relationship with the physical interface. When forwarding a packet, first encapsulate the MPLS TE label on the outer layer of the packet, and then forward the packet through the physical interface corresponding to the tunnel interface.

S102: The first node generates a forwarding entry of the first node. The forwarding entry of the first node includes an outgoing interface, and the outgoing interface is a tunnel interface of a tunnel.

After generating the tunnel, the first node locally generates the forwarding entry of the first node, and the forwarding entry of the first node is a forwarding entry corresponding to the standby path. The forwarding entry of the first node includes the outgoing interface, and the outgoing interface is the tunnel interface of the tunnel. The forwarding entry of the first node is used to forward the message to the second node when the main path fails, that is, when the first node forwards the message, the message is forwarded to the second node according to the tunnel corresponding to the tunnel interface.

In the embodiment of the present application, the forwarding entry of the first node may be a routing entry for forwarding IP packets, or a label forwarding entry for forwarding MPLS packets.

If the forwarding entry of the first node is a routing entry for forwarding IP, the forwarding entry of the first node may further include a next-hop address, and the next-hop address is the IP address of the second node obtained in advance. The IP address of the second node is used by the first node to look up the address resolution protocol (ARP) table, obtain the media access control (MAC) address, and encapsulate the MAC address in the Ethernet header of the packet .

If the second node is calculated by the first node, then the first node needs to obtain the IP addresses of all nodes and the neighbor information of each node in the network topology from the source node to the destination node before calculating the Q space. The IP address of the second node. If the second node is designated in advance, the first node may obtain the IP address of the second node before generating the routing table entry of the first node. As to how to obtain the IP address of the second node belongs to information known to those skilled in the art, it will not be repeated here.

In addition to the next hop address and the outgoing interface, if the routing entry of the first node may also include the destination IP address, the destination address is the IP address of the destination node. After the main path fails, the first node finds the routing table entry corresponding to the standby path according to the IP address of the destination node carried in the packet, and obtains the outgoing interface in the routing table entry, that is, the tunnel interface. Then send the message to the second node through the tunnel corresponding to the tunnel interface.

When sending a message to the second node, the first node may encapsulate the MPLS TE label of the tunnel on the outer layer of the message. After receiving the message, the second node pops up the outer encapsulated label, and then processes the message.

If the forwarding entry of the first node is a label forwarding entry for forwarding MPLS packets, the forwarding entry of the first node may include the outgoing label in addition to the outgoing interface. In the embodiment of the present application, the outgoing label in the label forwarding entry of the first node may include a first label and a second label. The first label is the LDP label from the first node to the second node, and the second label is the MPLS TE label of the tunnel.

Among them, the first label can be obtained as follows: the first node establishes a remote LDP session with the second node to receive the first label sent by the second node, that is, the LDP label, and the LDP label is used for the second node pair The message is forwarded. That is, after the first node and the second node establish a remote LDP session, the second node can send the first label to the first node. The process of establishing a session may be that the first node sends the first hello message to the second node through the tunnel. After receiving the first hello message, the second node sends the second hello message to the first node. The second node establishes a remote LDP session.

When the first node sends an MPLS packet to the second node through the tunnel, the inner layer of the packet can encapsulate the first label, and the outer layer of the packet can encapsulate the second label. Then, after receiving the message, the second node pops up the outer second label to obtain the first label, and forwards the message according to the first label.

It should be noted that if the tunnel passes other nodes than the first node and the second node, the MPLS TE label sent by the second node to the first node is usually different from the MPLS TE label actually received by the first node because Other nodes need to exchange labels. For example, assuming that the tunnel passes through the third node, the second node sends the MPLS TE label 1 to the third node. After receiving the MPLS TE label 1, the third node performs label exchange, and exchanges it for MPLS TE label 2, and then sends the first node The node sends the MPLS TE label 2. Therefore, the MPLS TE label received by the first node is MPLS TE label 2, not MPLS TE label 1. Similarly, when forwarding the message, the outer label carried in the message sent by the first node is MPLS TE label 2, and after the third node receives the MPLS TE label 2, the label is exchanged for the message, that is, in the message Replace the outer label of MPLS with TE label 1, and then send the message carrying MPLS TE label 1 to the second node. After receiving the message carrying the outer MPLS TE label 1, the second node pops up the outer MPLS TE label 1, and then forwards the message according to the inner label.

In addition to the outgoing interface and the outgoing label, there may be an incoming label in the label forwarding entry of the first node. When the main path fails, the first node can search for the label forwarding entry of the backup path corresponding to the label in the received packet, obtain the corresponding outgoing interface and outgoing label, and remove the packet from the outgoing interface. That is, the tunnel interface is forwarded.

In the embodiment of the present application, the first node establishes a tunnel to the second node that is the Q node, and generates a forwarding entry of the first node according to the tunnel interface of the tunnel, so that the first node can be in the case of a failure of the main path. Switch the traffic to the backup path in time, that is, the first node can timely send the packet to the second node through the tunnel corresponding to the tunnel interface, and the second node sends the packet to the destination node. Compared with the existing solution where the PQ node cannot be calculated, the path from the source node to the destination node can only be re-converged after the failure of the main path to calculate the packet forwarding, the embodiments of the present application can effectively shorten the traffic switching The time required to reduce business losses. If the first node automatically calculates the Q node as the second node, it can also reduce manual workload and improve the efficiency of generating the forwarding entry of the first node.

The above are the technical solutions provided by the embodiments of the present application from the perspective of the first node, and the following is the perspective of the second node.

After receiving the tunnel establishment request sent by the first node and generating the MPLS TE label of the tunnel, the second node may send the MPLS TE label of the tunnel to the first node.

Optionally, after the first node establishes a remote LDP session with the second node, the second node generates a first label and sends it to the first node. The first label is an LDP label from the first node to the second node. After generating the first label, the second node may generate the forwarding entry of the second node.

Similar to the first node, the forwarding entry of the second node may also be a routing entry for forwarding IP packets, or a label forwarding entry for forwarding MPLS packets.

If the forwarding entry of the second node is a routing entry, the routing entry of the second node may include at least the destination IP address, the next hop address, and the outgoing interface. The destination IP address in the routing table entry of the second node is the IP address of the destination node. The next hop address in the second node routing table entry is the IP address of the next hop node in the shortest path from the second node to the destination node. The outgoing interface in the routing entry of the second node is an interface that can forward the packet to the next hop of the second node.

After receiving the IP packet forwarded by the first node through the tunnel, the second node searches for the corresponding routing entry according to the destination IP address carried in the IP packet, and obtains the corresponding next hop address and outgoing address in the routing entry Interface, and forward the packet to the next-hop node of the second node according to the next-hop address and the outgoing interface.

When the first node encapsulates the MPLS TE label of the tunnel in the outer layer of the packet, after the second node receives the packet, the outer encapsulated label is popped up, and then according to the destination IP address carried in the packet and the second node Routing table entry forwards the message

If the forwarding entry of the second node is a label forwarding entry, the label forwarding entry of the second node may include at least an incoming label, an outgoing label, and an outgoing interface. The incoming label is the first label, the outgoing label is the LDP label from the second node to the next hop node, and the outgoing interface is the interface that can forward the packet to the next hop of the second node.

After receiving the MPLS packet forwarded by the first node through the tunnel, the second node pops up the outer label of the MPLS packet, that is, the second label. According to the inner label in the MPLS packet, that is, the first label, the label forwarding entry whose second label is the second label is searched, and the outgoing label and the outgoing interface in the label forwarding entry are obtained. The second node replaces the outgoing label in the label forwarding entry with the inner label in the packet, and forwards the packet to the next hop node of the second node according to the outgoing interface in the label forwarding entry.

The technical solution of the present application will be described in detail in conjunction with the application scenario shown in FIG. 1 below.

Refer to FIG. 3, which is a schematic diagram of packet forwarding corresponding to the example shown in FIG. Since node B is a Q node, a tunnel can be established from source node S to node B. The intermediate node of the tunnel is node A, that is, the tunnel passes node A. When establishing a tunnel, the source node S sends a tunnel establishment request to the node A, and the destination address of the tunnel establishment request is the IP address of the node B. After receiving the tunnel establishment request, the node A forwards the tunnel establishment request to the node B. Node B generates the MPLS TE label of the tunnel, that is, 46002, and carries the label in the reply message to node A. After receiving the response message, node A performs label exchange, that is, the MPLS TE label of the tunnel 46002 in the response message is exchanged to the MPLS TE label 46001 of the tunnel, and forwards the response message carrying the MPLS TE label 46001 of the tunnel Give source node S. At the same time, the node A stores the mapping relationship of the MPLS TE label 46002 of the destination node D tunnel.

The source node S can establish a remote LDP session with the node B. After establishing the remote LDP session, the node B sends the source node S the LDP label from the source node S to the node B, that is, 56231.

After establishing the tunnel, the source node S generates a label forwarding entry of the source node S. The label forwarding entry of the source node S includes an outgoing interface and an outgoing label. The outgoing interface is a tunnel interface established by the source node S to the tunnel of node B. The output label includes a first label 56231 and a second label 46001. Node B generates a label forwarding entry for node B. The label forwarding entry for node B includes an incoming label, an outgoing label, and an outgoing interface. The incoming label of the node B label forwarding entry is 56231, the outgoing label is the LDP label from node B to the destination node D, namely 56232; the outgoing interface is the interface connecting the node B and the destination node D.

When the main path from the source node S to the destination node D fails, the source node S finds the corresponding outgoing label and outgoing interface according to searching the local label forwarding entry. The source node S encapsulates the LDP label 56231 in the inner layer of the packet, and the outer layer encapsulates the MPLS TE label 46001 in the tunnel, and sends the encapsulated packet out through the tunnel interface. The physical interface corresponding to the tunnel interface is the source node S and the node A physical interface connected.

After receiving the message, Node A performs label exchange on the outer label of the message, that is, replaces the outer label of the message with the tunnel's MPLS TE label 46002. Then node A sends the message carrying the tunnel's MPLS TE label 46002 to node B.

After receiving the packet, Node B pops up the outer label 46002 of the packet, obtains the inner label 56231, and finds the label forwarding entry with the label 56231. The label forwarding entry includes the outgoing label 56232 and the outgoing interface . Node B then replaces the incoming label of the message with 56232, and sends the message out through the interface connecting node B and destination node D, so that destination node D can receive the message.

In the above solution, the source node S establishes a tunnel to the node B, and generates a label forwarding entry of the source node S according to the tunnel interface of the tunnel, that is, a label forwarding entry corresponding to the backup path. When the main path fails, the source node S can forward the packet in time according to the label forwarding entry corresponding to the backup path, reducing the time of traffic interruption and the probability of service damage.

Referring to FIG. 4, this figure is a structural block diagram of a forwarding entry generation device provided by an embodiment of the present application.

The forwarding entry generation device provided in the embodiment of the present application is applied to a first node, and the first node can implement the function of the first node in the embodiment shown in FIG. 2. The first node is the source node of the main path. The first node includes: a tunnel establishment unit 401 and an entry generation unit 402. The tunnel establishment unit 401 is used to execute S101 in the embodiment shown in FIG. 2, and the entry generation unit 402 is used to execute S102 in the embodiment shown in FIG. 2. specific,

The tunnel establishment unit 401 is used to establish a tunnel to a second node. The second node is a Q node belonging to the Q space in the network topology from the source node to the destination node of the main path, and the tunnel does not pass through the main path.

The entry generation unit 402 is used to generate a forwarding entry of the first node. The forwarding entry of the first node includes an outgoing interface, and the outgoing interface is a tunnel interface of the tunnel. The forwarding entry of the first node is used when the primary path fails Forward the message to the second node.

Optionally, the message is an IP message or an MPLS message.

Referring to FIG. 5, an embodiment of the present application further provides a forwarding entry generating device 500. The device is a first node, and the device 500 can implement the function of the first node in the embodiment shown in FIG. 2. The device 500 includes a storage unit 501, a processing unit 502, and a communication unit 503,

Storage unit 501 for storing instructions;

The processing unit 502 is configured to execute the instructions in the storage unit 501 and execute the foregoing forwarding entry generation method applied to the first node in the embodiment shown in FIG. 2;

The communication unit 503 is used to communicate with the second node.

The storage unit 501, the processing unit 502 and the communication unit 503 are connected to each other through a bus 504; the bus 504 may be a peripheral component interconnection (PCI) bus or an extended industry standard architecture (extended industry standard architecture, EISA) Bus etc. The bus can be divided into address bus, data bus, control bus and so on. For ease of representation, only a thick line is used in FIG. 5, but it does not mean that there is only one bus or one type of bus.

The storage unit 501 may be a random-access memory (RAM), flash memory, flash, read-only memory (ROM), erasable programmable read-only memory (erasable programmable read only memory), EPROM), electrically erasable programmable read only memory (electrically erasable programmable read only memory (EEPROM), register (register), hard disk, removable hard disk, CD-ROM or any other form of storage medium known to those skilled in the art.

The processing unit 502 may be, for example, a central processing unit (CPU), a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), or field programmable Gate array (field programmable gate array, FPGA) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. It can implement or execute various exemplary logical blocks, modules, and circuits described in conjunction with the disclosure of the present application. The processor may also be a combination of computing functions, for example, including one or more microprocessor combinations, DSP and microprocessor combinations, and so on.

The communication unit 503 may be, for example, an interface card or the like, and may be an Ethernet interface or an asynchronous transfer mode (Asynchronous Transfer Mode, ATM) interface.

An embodiment of the present application also provides a computer-readable storage medium, including instructions that, when run on a computer, cause the computer to execute the foregoing forwarding entry generation method.

An embodiment of the present application further provides a forwarding entry generation system, which includes the first node and the second node provided in the embodiment shown in FIG. 2.

The terms "first", "second", "third", "fourth", etc. (if any) in the description and claims of this application and the above drawings are used to distinguish similar objects without using To describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments described herein can be implemented in an order other than what is illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, processes, methods, systems, products or devices that contain a series of steps or units need not be limited to those clearly listed Those steps or units, but may include other steps or units not explicitly listed or inherent to these processes, methods, products, or equipment.

Those skilled in the art can clearly understand that for the convenience and conciseness of the description, the specific working process of the system, device and unit described above can refer to the corresponding process in the foregoing method embodiments, which will not be repeated here.

In the several embodiments provided in this application, it should be understood that the disclosed system, device, and method may be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a division of logical functions. In actual implementation, there may be other divisions, for example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored, or not implemented. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection may be indirect coupling or communication connection through some interfaces, devices or units, and may be in electrical, mechanical or other forms.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units may be integrated into one unit. The above integrated unit may be implemented in the form of hardware or software functional unit.

If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application essentially or part of the contribution to the existing technology or all or part of the technical solution can be embodied in the form of a software product, the computer software product is stored in a storage medium , Including several instructions to enable a computer device (which may be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods described in the embodiments of the present application. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk and other media that can store program code .

Those skilled in the art should realize that in one or more of the above examples, the functions described in the present invention may be implemented by hardware, software, firmware, or any combination thereof. When implemented in software, these functions can be stored in a computer-readable medium or transmitted as one or more instructions or code on a computer-readable medium. Computer-readable media includes computer storage media and communication media, where communication media includes any medium that facilitates transfer of a computer program from one place to another. The storage medium may be any available medium that can be accessed by a general-purpose or special-purpose computer.

The specific embodiments described above further describe the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific embodiments of the present invention.

As mentioned above, the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, persons of ordinary skill in the art should understand that they can still The technical solutions described in the embodiments are modified, or some of the technical features are equivalently replaced; and these modifications or replacements do not deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

A forwarding entry generation method, characterized in that the method includes:

The first node establishes a tunnel to a second node, the first node is the source node of the main path, and the second node is the Q space in the network topology from the source node to the destination node of the main path Q node, the tunnel does not pass through the main path;

The first node generates a forwarding entry of the first node, the forwarding entry of the first node includes an outgoing interface, the outgoing interface is a tunnel interface of the tunnel, and the forwarding entry of the first node It is used to forward a message to the second node when the main path fails.
The method according to claim 1, wherein the forwarding entry of the first node is a routing entry or a label forwarding entry.
The method according to claim 2, wherein if the forwarding entry of the first node is the routing entry, then the forwarding entry of the first node further includes a next hop address, the The next hop address is an Internet protocol IP address of the second node that is obtained in advance.
The method according to claim 2, wherein if the forwarding entry of the first node is the label forwarding entry, the label forwarding entry further includes an outgoing label, and the outgoing label includes a A label and a second label, the first label is a label distribution protocol LDP label from the first node to the second node, the second label is a multi-protocol label switching traffic engineering MPLS TE of the tunnel label.
The method according to claim 4, wherein the method further comprises:

The first node establishes a remote LDP session with the second node to receive the first label sent by the second node.
The method according to claim 4 or 5, wherein the method further comprises:

When the main path fails, the first node sends the message to the second node through the tunnel, the inner layer of the message encapsulates the first label, and the outer layer of the message encapsulates the Describe the second label.
The method according to any one of claims 1-6, wherein the second node is a Q node in the Q space that is closest or farthest from the first node.
The method according to any one of claims 1-7, wherein the tunnel is a resource reservation protocol-traffic engineering RSVP-TE tunnel.
The method according to any one of claims 1-8, wherein the message is an IP message or an MPLS message.
A forwarding entry generation device is characterized by being applied to a first node, where the first node is a source node of a main path, and the device includes:

A tunnel establishment unit is used to establish a tunnel to a second node, which is a Q node belonging to the Q space in the network topology from the source node to the destination node of the main path, and the tunnel does not pass through The main path;

An entry generating unit is used to generate a forwarding entry of the first node, the forwarding entry of the first node includes an outgoing interface, the outgoing interface is a tunnel interface of the tunnel, and the forwarding of the first node The published item is used to forward a message to the second node when the main path fails.
The apparatus according to claim 10, wherein the forwarding entry of the first node is a routing entry or a label forwarding entry.
The apparatus according to claim 11, wherein if the forwarding entry of the first node is the routing entry, the forwarding entry of the first node further includes a next hop address, the The next hop address is an Internet protocol IP address of the second node that is obtained in advance.
The apparatus according to claim 11, wherein if the forwarding entry of the first node is the label forwarding entry, the label forwarding entry further includes an outgoing label, and the outgoing label includes a A label and a second label, the first label is a label distribution protocol LDP label from the first node to the second node, and the second label is a multi-protocol label switching traffic engineering MPLS TE of the tunnel label.
The device according to claim 13, wherein the device further comprises:

The session establishment unit is configured to establish a remote LDP session with the second node to receive the first label sent by the second node.
The device according to claim 13 or 14, wherein the device further comprises:

The message sending unit is configured to send the message to the second node through the tunnel when the main path fails, the inner layer of the message encapsulates the first label, and the outer layer of the message The second label is encapsulated.
The apparatus according to any one of claims 10-15, wherein the second node is a Q node that is closest to or farthest from the first node in the Q space.
The apparatus according to any one of claims 10 to 16, wherein the tunnel is a resource reservation protocol-traffic engineering RSVP-TE tunnel.
The device according to any one of claims 10-17, wherein the message is an IP message or an MPLS message.
A forwarding entry generation device, characterized in that the device is a first node, and the first node includes a storage unit, a processing unit, and a communication unit,

The storage unit is used to store instructions;

The processing unit is configured to execute the instruction in the memory and execute the method according to any one of claims 1-9;

The communication unit is used to communicate with the second node.
A computer-readable storage medium including instructions which, when run on a computer, cause the computer to perform the method of any one of claims 1-9 above.