A path protection method based on hierarchical controller

Abstract

The present invention belongs to the field of network technology and security. In order to solve the technical problems that the existing technology cannot protect all nodes and links in the path, and when there is a cross failure in the primary and backup paths, it is necessary to wait for the controller to sense the topology change and recalculate and send the path before the service can be restored, and the convergence time is long, a protection scheme for the service path is proposed, which can theoretically cover all single nodes and links in the service path. In the scenario of the primary and backup paths crossing non-adjacent nodes, the backup path can be quickly switched to. The three parts of time for reporting topo changes to the controller, the controller calculating the path, and the path re-issuing are saved.

Description

Technical Field

[0001] The present invention relates to the field of network technology and security, and in particular to a path protection method based on a hierarchical controller. Background Art

[0002] In the SR technology theory system, the main methods for protecting nodes and links are LFA, RLFA and TI-LFA. LFA and RLFA are limited by the topology and network configuration and cannot guarantee 100% protection; TI-LFA can theoretically guarantee 100% protection by combining node labels and adjacency labels (see Figure 1 , Figure 2 ). However, the node label path used by TI-LFA follows the route change, that is, the traffic direction changes with route optimization and route convergence, which is inconsistent with the controller's strong control idea. Therefore, this solution is usually not used when the SDN controller processes the protection path.

[0003] In the field of SDN, we can look at existing solutions, such as "A link protection method and local repair node based on SR-TE tunnel" (CN201910392885.7), "Extended BGP protection for SR path entry protection" (CN202080041907.6), "PACKET ROUTING BASED ON COMMON NODE PROTECTION" (US16575945), etc. To summarize their ideas, the controller is responsible for calculating the primary and backup non-shared or partially shared paths according to the constraints, and establishing the primary and backup LSPs. According to business needs, the controller can also calculate the escape path that ignores the constraints. When the primary path fails, the traffic switches to the backup path. When the backup path also fails, it switches to the escape path. According to user planning, SRLG (shared risk link group) can also be set to avoid risk points when calculating the path. However, these path calculation implementations can only play a partial protection effect. In some special scenarios, such as when the primary and backup path nodes cross-fail, the traffic cannot be bypassed, resulting in business interruption.

[0004] From the above analysis, we can see that the current node and link protection ideas have the following problems: when there are cross-fault points in the primary, backup and escape paths, the service will be interrupted even if there is an end-to-end path that meets the constraints. That is, the existing method cannot protect all nodes and links in the path. When there are cross-faults in the primary, backup and escape paths, the service can only be restored after the controller senses the topology changes and recalculates and sends down the path, which takes a long time to converge. Summary of the invention

[0005] In view of this, the present invention provides a method and system for protecting a service path.

[0006] In a first aspect, the present invention provides a path protection method based on a hierarchical controller, the method comprising the following steps:

[0007] S1, hierarchical management topology, the controller adopts a hierarchical structure. The inter-domain controller collects all topologies and abstracts the intra-domain topology; the intra-domain controller collects and manages all topologies within the domain.

[0008] S2, recursively calculate the path node by node, the controller calculates the main service path according to the constraints, and then calculates the protection path from the service starting point to the previous node of the service end point; the protection path calculation principle is to calculate from the protection point to the end point to meet the constraints and not share the path with the protected node or path.

[0009] Preferably, step S2 includes the following sub-steps:

[0010] S21, inter-domain abstract path calculation, the inter-domain controller calculates the path from the starting point to the inter-domain node, the inter-domain path, and the path from the inter-domain node to the end point based on the abstract topology, and performs inter-domain recursive path calculation node by node;

[0011] S22, service segmentation: the inter-domain controller splits the calculated path by domain, and divides the path into several parts: from the starting point to the inter-domain node, between the inter-domain nodes, and from the inter-domain node to the end point.

[0012] S23, detailed intra-domain path calculation. The intra-domain controller generates non-cross-domain start and end points based on the path information split by the inter-domain controller or the non-cross-domain business scenario, calculates the path from the start point to the end point based on the constraints, and recursively calculates the protection path from the business start point to the previous node of the end point.

[0013] In a second aspect, the present invention further provides a path protection system based on a hierarchical controller, comprising a controller and a forwarding device, wherein the controller comprises a controller and a forwarding device, and is characterized in that:

[0014] The controller includes a domain controller and an inter-domain controller;

[0015] The forwarding device is dual-standard connected to the domain controller and the inter-domain controller;

[0016] The domain controller and inter-domain controller establish control channels with all forwarding devices for issuing path configuration and hosting services;

[0017] The inter-domain controller establishes an interactive channel with the domain controller for transmitting service and cross-path calculation information.

[0018] The protection scheme for the service path provided by the present invention can theoretically cover all single nodes and links in the service path. In the scenario where the primary and backup paths cross and non-adjacent nodes fail, the backup path can be quickly switched to. This saves the time of reporting topo changes to the controller, calculating the path by the controller, and re-issuing the path. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the description of the present invention or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 Node / link protection path;

[0021] Figure 2 Original topology;

[0022] Figure 3 Inter-domain path calculation topology;

[0023] Figure 4 The inter-domain controller calculates the path;

[0024] Figure 5 Splitting of inter-domain controller services;

[0025] Figure 6 Start node cross calculation;

[0026] Figure 7 Inter-domain node cross-path calculation;

[0027] Figure 8 Calculate the route at the end point intersection;

[0028] Fig. 9 Path to be spliced;

[0029] Fig.10 splicing path;

[0030] Fig.11 Single-node single-path failure;

[0031] Fig.12 Node link cross failure;

[0032] Fig.13 Component deployment scheme. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings, and "multiple" generally includes at least two.

[0035] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0036] As used herein, the words "if" and "if" may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0037] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a product or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such a product or system. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the product or system including these elements.

[0038] In addition, the step sequence in the following method embodiments is only an example and not a strict limitation.

[0039] Embodiment 1

[0040] The present invention provides a path protection method based on a hierarchical controller, the method comprising the following steps:

[0041] S1, hierarchical management topology, the controller adopts a hierarchical structure. The inter-domain controller collects all topologies and abstracts the intra-domain topology; the intra-domain controller collects and manages all topologies within the domain.

[0042] In the specific implementation, the controller adopts a hierarchical structure. The inter-domain controller collects all topologies and abstracts the intra-domain topology after collection, that is, the path from the intra-domain node to the inter-domain node is selected according to the TE attribute (such as bandwidth) (for example, N optimal paths are retained), and other reachable paths are ignored. When the bandwidth occupancy rate of the optimal path reaches M, the abstraction is performed again (the N and M values ​​can be set according to business needs). This ensures that the inter-domain controller retains a smaller amount of high-quality topology information. The intra-domain controller collects and manages the entire topology within the domain.

[0043] S2, recursively calculate the path node by node, the controller calculates the main service path according to the constraints, and then calculates the protection path from the service starting point to the previous node of the service end point; the protection path calculation principle is to calculate from the protection point to the end point to meet the constraints and not share the path with the protected node or path.

[0044] In the specific implementation, the controller calculates the main service path according to the constraints, and then calculates the protection path from the service starting point to the node before the service end point. The principle of main path calculation is to calculate the nodes and paths that meet the constraints from the starting point to the end point; the principle of protection path calculation is to calculate from the protection point to the end point to meet the constraints and not share the path with the protected node or path. Figure 1 Node / link protection path; when a node fails, the backup path can be switched. This method can quickly recover when multiple nodes on the primary and backup paths fail.

[0045] In a specific implementation, the step S2 includes the following sub-steps:

[0046] S21, inter-domain abstract path calculation, the inter-domain controller calculates the path from the start point to the inter-domain node, the inter-domain path, and the inter-domain node to the end point based on the abstract topology, and performs inter-domain recursive path calculation node by node.

[0047] In the specific implementation, when calculating the path, the inter-domain controller first calculates the path from the start point to the inter-domain node, the inter-domain path, and the inter-domain node to the end point according to the abstract topology. And perform inter-domain recursive path calculation according to the description of node-by-node recursive path calculation in S2. After this calculation, the inter-domain nodes and protection paths traversed between the service start point and the end point are determined.

[0048] For example, Figure 2 In the original topology, the cross-domain path starts at C1 and ends at C2, and the path spans two domains. After topology abstraction, the path calculation topology obtained by the inter-domain controller only contains the start and end nodes and inter-domain nodes, ignoring other irrelevant nodes in the domain, such as the attached Figure 3The inter-domain path calculation topology is shown in the figure. The path from the P node to the ASBR node is obtained by the inter-domain controller in an abstract manner according to the constraints (such as bandwidth). When calculating the path, the inter-domain controller does not need to know the specific path from the P node to the ASBR node and the nodes traversed. It only needs to confirm that there is a path from the P node to the ASBR that meets the constraints based on the constraint information of the abstract topology (such as bandwidth). The inter-domain controller path calculation result is shown in the attached figure. Figure 4 The inter-domain controller calculates paths.

[0049] S22, service segmentation, the inter-domain controller splits the calculated path by domain, and splits the path into several parts: from the starting point to the inter-domain node, between the inter-domain nodes, and from the inter-domain node to the end point.

[0050] In the specific implementation, after the inter-domain abstract path calculation, the domains that the service traverses have been determined. The inter-domain controller splits the calculated path by domain, splitting the path into several parts: the starting point to the inter-domain node, between the inter-domain nodes, and from the inter-domain node to the end point, and distributes them as the starting point and the end point to the intra-domain controller for detailed path calculation. Of course, if the service belongs to only one domain, the path calculation of the service is completed by the corresponding intra-domain controller alone. Please see the attached Figure 5 Inter-domain controller service splitting.

[0051] S23, detailed intra-domain path calculation. The intra-domain controller generates non-cross-domain start and end points based on the path information split by the inter-domain controller or the non-cross-domain business scenario, calculates the path from the start point to the end point based on the constraints, and recursively calculates the protection path from the business start point to the previous node of the end point.

[0052] The specific calculation method is:

[0053] S231, split the path into a section from the starting node to the cross-domain node, and respectively calculate the path from the starting node to the cross-domain primary and standby nodes (if the cross-domain node is a single node, calculate the path from the starting node to the cross-domain single node) and the protection path from the node included in the path to the cross-domain standby primary node (if the cross-domain node is a single node, calculate the protection path from the node included in the path to the cross-domain single node), that is, cross-path calculation, see Attachment Figure 6 The starting node cross-path calculation. In the figure, the domain controller calculates the path from C1 to ASBR1 and the path from C1 to ASBR2, and calculates the path from P1 to ASBR2 contained in the path from C1 to ASBR1 and the path from P2 to ASBR1 contained in the path from C1 to ASBR2.

[0054] S232: Take the inter-domain node to the inter-domain node as a section, and calculate the cross paths between the inter-domain nodes respectively. If the inter-domain node is a single node, calculate the path between the single nodes including the protection path from the node to the cross-domain single node.

[0055] Please see attached Figure 7Inter-domain node cross-path calculation. In the figure, the intra-domain controller calculates the path from ASBR1 to ASBR3 and the path from ASBR2 to ASBR4. It also calculates the path from node P3 to ASBR4 included in the path from ASBR1 to ASBR3 and the path from node P4 to ASBR3 included in the path from ASBR2 to ASBR4. A path may contain multiple inter-domain node-to-inter-domain node paths, and the paths can be calculated separately according to the above method.

[0056] S233: Take the path from the inter-domain node to the end point as a section, and respectively calculate the protection path from the node to the end point included in the path from the inter-domain to the end point and the path from the inter-domain node to the end point.

[0057] In the specific implementation, if the inter-domain node is a single node, the path from the single node to the end point and the protection path from the path containing the node to the end point are calculated. Figure 8 End point cross-path calculation. As shown in the figure, calculate the paths from ASBR5 to C2 and ASBR6 to C2 respectively; calculate the protection path from ASBR5 to C2 and the protection path from ASBR6 to C2; calculate the protection path from P5 to C2 included in the main path from ASBR5 to C2 and the protection path from P6 to C2 included in the main path from ASBR6 to C2.

[0058] S24, path splicing. After calculating the intra-domain path, the intra-domain controller reports the calculation result to the inter-domain controller. The inter-domain controller obtains the path to be spliced. The inter-domain controller splices the intra-domain controller calculation result with the inter-domain calculation result. Fig. 9 Path to be spliced.

[0059] The path from the starting point to the inter-domain node is replaced with the cross-path calculation result of the controller within the domain; the path from the inter-domain node to the inter-domain node is replaced with the cross-path calculation result of the controller within the domain; the path from the inter-domain node to the end point is replaced with the cross-path calculation result of the node within the domain; the cross-domain controller retains the cross-domain path calculation result. Fig.10 Stitching paths.

[0060] At this point, the controller has completed path calculation.

[0061] After the controller sends the calculation result to the forwarder, the traffic is forwarded normally. When the link where the path is located fails, the node directly connected to the link senses it and switches the path. Through the swap operation, the label is exchanged to the backup path of the node. Fig.11 In the case of a single-node single-path failure, the P1 node senses the failure of the ASBR1 and the link between P1 and ASBR1, and performs a path switching operation, swapping the label stack, and switching to the backup path of P1.

[0062] When multiple nodes or links fail, the node only detects the next hop failure and switches the path. Fig.12As shown in the case of a node link cross failure, the P1 node senses the P1 to ASBR1 link failure, exchanges labels, and switches the path to P1->ASBR2->P4->ASBR4->ASBR6->P6->C2. After the path is switched, the traffic reaches ASBR2. ASBR2 senses the P4 node failure, exchanges labels, and switches the path to ASBR2->P3->ASBR3->ASBR5->P5->C2. The message is forwarded along the way, the label is popped, and the traffic is directed to C2.

[0063] Compared with existing methods, this method can provide protection for all nodes and links in the path. It can complete the rapid switching and recovery of the service path when there are faulty nodes or links in both the primary and backup paths, but the fault points or links are not adjacent, saving the service recovery time of the controller sensing the fault, calculating the path, and re-updating the path.

[0064] Embodiment 2

[0065] The present invention also provides a path protection system based on a hierarchical controller, which is used to implement the path protection method described in other embodiments of the present invention. The path protection system includes a controller and a forwarding device. The controller includes a domain controller and an inter-domain controller.

[0066] Wherein, the forwarding device is dual-standard connected to the domain controller and the inter-domain controller;

[0067] The domain controller and inter-domain controller establish control channels with all forwarding devices for issuing path configuration and hosting services;

[0068] The inter-domain controller establishes an interactive channel with the domain controller for transmitting service and cross-path calculation information.

[0069] The controller module consists of a topology processing module, a topology abstraction module, a path calculation module, a southbound protocol stack module, a storage module, and a path splitting module. The topology abstraction module and the path splitting module are unique to the inter-domain controller, and the other four modules are shared by the inter-domain controller and the intra-domain controller.

[0070] The southbound protocol module consists of two parts. The first part is the routing protocol, which is used to collect topology information. It can be BGP or IGP (ISI, OSPF, etc.). The second part is the protocol that sends the calculation results to the south, usually the PCEP protocol.

[0071] The topology processing module is used to process the topology information collected by the original routing protocol into node and connection information that can be used for path calculation.

[0072] The topology abstraction module is used by the inter-domain controller to select N topology nodes generated by the topology processing module as the path calculation topology based on necessary conditions, such as bandwidth. After abstraction, the inter-domain controller obtains the abstract path from each node in the domain to the boundary point of the domain and the path calculation topology composed of the inter-domain nodes.

[0073] The storage module is used to store original topology, abstract topology, path calculation topology and business information.

[0074] The path calculation module is used to calculate the end-to-end path based on the path calculation topology and business needs, and output the node information along the way.

[0075] The path splitting module is used to split the path according to the domain information after the inter-domain controller calculates the path, identify the starting and ending points of the single-domain path, and send it to the domain controller for path calculation.

[0076] In the specific implementation, the component deployment scheme is as shown in the attached Fig.13 As shown:

[0077] The forwarding device is dual-connected to the domain controller and the inter-domain controller, and establishes a topology management channel with the routing protocol stack. The controller establishes a control channel with all forwarding devices to issue path configuration and managed services (the full connection line is omitted in the figure). The inter-domain controller establishes an interactive channel with the domain controller to transmit services and cross-path calculation information.

[0078] The cross-path calculation logic is as follows: The forwarder sends the path calculation service to the inter-domain controller. The inter-domain controller determines whether the service belongs to only one domain. If it belongs to only one domain, it distributes the service to the corresponding domain controller for processing. If it is a cross-domain service, the inter-domain controller performs inter-domain cross-path calculation based on the path calculation topology and service constraints. The inter-domain cross-path calculation result determines the domain node information that the path passes through.

[0079] The inter-domain controller splits the inter-domain cross-path calculation results by domain into three types: starting point to inter-domain node, inter-domain node to inter-domain node (may have multiple), and inter-domain node to end point. The split path start and end points are sent to the corresponding domain controllers for detailed path calculation.

[0080] After receiving the path calculation request from the inter-domain controller, the domain controller calculates the path from the starting point to the inter-domain node and the protection path from the node included in the path to the inter-domain node; calculates the path from the inter-domain node to the inter-domain node across the domain, and calculates the protection path from the node included in the path to the inter-domain node; calculates the path from the inter-domain node to the end point and the protection path from the node included in the path to the end point. When calculating the protection path, it is necessary to avoid the same path as the protected path.

[0081] The domain controller reports the calculation result to the inter-domain controller. The inter-domain controller combines the calculation result of the domain controller with its own cross-domain cross-calculation result, replaces the intra-domain path between the inter-domain nodes with the detailed intra-domain path, retains its own inter-domain calculation path, and splices it into an end-to-end path. The domain controller sends the end-to-end path to the forwarding device. The forwarding device guides the P1 traffic to the destination node according to the label. When a node or link in the path fails, the forwarding node switches to the protection path; each forwarding node is responsible for switching the next-hop fault path to ensure rapid convergence of the fault.

[0082] The present invention also provides a computer device. The computer device is in the form of a general-purpose computing device. The components of the computer device may include but are not limited to: one or more processors or processing units, a system memory, and a bus connecting different system components.

[0083] Computer devices typically include a variety of computer system readable media. These media can be any available media that can be accessed by the computer device, including volatile and non-volatile media, removable and non-removable media.

[0084] The system memory may include a computer system readable medium in the form of volatile memory. The memory may include at least one program product having a set (eg, at least one) of program modules configured to perform the functions of various embodiments of the present invention.

[0085] The processing unit executes various functional applications and data processing by running programs stored in the system memory, such as implementing the methods provided in other embodiments of the present invention.

[0086] The present invention also provides a storage medium containing computer executable instructions, on which a computer program is stored. When the program is executed by a processor, the method provided by other embodiments of the present invention is implemented.

[0087] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A path protection method based on a hierarchical controller, characterized in that: The method comprises the following steps, S1, hierarchical management topology, the controller adopts a hierarchical structure, the inter-domain controller collects all topologies and abstracts the intra-domain topology; The domain controller collects and manages the entire topology within the domain; S2, recursively calculate the path node by node, the controller calculates the main service path according to the constraints, and then calculates the protection path from the service starting point to the node before the service end point; the protection path calculation principle is that the calculation from the protection point to the end point meets the constraints and does not share the path with the protected node or path; The step S2 comprises the following sub-steps: S21, inter-domain abstract path calculation, the inter-domain controller calculates the path from the starting point to the inter-domain node, the inter-domain path, and the path from the inter-domain node to the end point based on the abstract topology, and performs inter-domain recursive path calculation node by node; S22, service segmentation: the inter-domain controller splits the calculated path by domain, and divides the path into several parts: from the starting point to the inter-domain node, between the inter-domain nodes, and from the inter-domain node to the end point. S23, detailed intra-domain path calculation: the intra-domain controller generates non-inter-domain start and end points based on the path information split by the inter-domain controller or the non-inter-domain service scenario, calculates the path from the start point to the end point based on the constraints, and recursively calculates the protection path from the service start point to the previous node of the end point; The specific calculation method of the detailed path calculation in the domain in S23 is: S231, split the path into a section from the starting node to the cross-domain node, and respectively calculate the path from the starting node to the cross-domain active and standby nodes and the protection path from the node included in the path to the cross-domain active and standby nodes; S232, taking the inter-domain node to the inter-domain node as a section, respectively calculating the cross paths between the inter-domain nodes; if the inter-domain node is a single node, then calculating the path between the single nodes including the protection path from the node to the cross-domain single node; S233: Take the inter-domain node to the end point as a segment, and calculate the protection path from the node to the end point included in the inter-domain to the end point and the inter-domain node to the end point path. S24, path splicing. After calculating the intra-domain path, the intra-domain controller reports the calculation result to the inter-domain controller. The inter-domain controller obtains the path to be spliced. The inter-domain controller splices the calculation result of the intra-domain controller with the calculation result of the inter-domain. The specific method of path splicing in S24 is as follows: The path from the starting point to the inter-domain node is replaced with the cross-path calculation result of the intra-domain controller; the path from the inter-domain node to the inter-domain node is replaced with the cross-path calculation result of the intra-domain controller; the path from the inter-domain node to the end point is replaced with the cross-path calculation result of the intra-domain node; and the cross-domain controller retains the cross-domain path calculation result.

2. The path protection method according to claim 1, characterized in that: When a node fails, the backup path can be switched; The switching of the backup path includes: when a link where the path is located fails, the link directly connected node senses it and switches the path, and through a swap operation, exchanges the label to the backup path of the node.

3. A path protection system based on a hierarchical controller for implementing the path protection method according to any one of claims 1 to 2, comprising a controller and a forwarding device, characterized in that: The controller includes a domain controller and an inter-domain controller; The forwarding device is dual-standard connected to the domain controller and the inter-domain controller; The domain controller and inter-domain controller establish control channels with all forwarding devices for issuing path configuration and hosting services; The inter-domain controller establishes an interactive channel with the domain controller for transmitting service and cross-path calculation information.

4. The path protection system according to claim 3, characterized in that: The domain controller includes a topology processing module, a topology abstraction module, a path calculation module, a southbound protocol stack module, a storage module and a path splitting module; The inter-domain controller includes a topology processing module, a path calculation module, a southbound protocol stack module, and a storage module.

5. The path protection system according to claim 4, characterized in that: The southbound protocol module includes a first protocol and a second protocol, wherein the first protocol is a routing protocol for collecting topology information; the second protocol is a protocol for sending path calculation results southward; The topology processing module is used to process the topology information collected by the original routing protocol into node and connection information available for path calculation; The path calculation module is used to calculate the end-to-end path according to the path calculation topology combined with business needs, and output the node information along the way.

6. The path protection system according to claim 4, characterized in that: The topology abstraction module is used for the inter-domain controller to select N topology nodes generated by the topology processing module as the path calculation topology according to necessary conditions; the inter-domain controller obtains the abstract path from each node in the domain to the boundary point of the domain and the path calculation topology composed of the inter-domain nodes; The path splitting module is used to split the path according to the domain information after the inter-domain controller calculates the path, identify the starting and ending points of the single-domain path, and send it to the domain controller for path calculation.

7. The path protection system according to claim 3, characterized in that: The forwarding device is used to guide the traffic to the destination node according to the label; and when a node or link in the path fails, the forwarding node switches the protection path.

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