Path determination method, communication device, and computer-readable storage medium

Abstract

The application discloses a path determination method, a communication device and a computer readable storage medium, and belongs to the technical field of communication. The path determination method provided by the application comprises the following steps: acquiring link state advertisement information of all first links between a first routing node and a second routing node, wherein the link advertisement information of the first links comprises SRLG information of the first links; determining second links from all the first links according to the SRLG information of the first links; presetting an increase adjustment on actual link costs of all the second links to obtain first target link costs corresponding to all the first links; and determining a rerouting recovery path between the first routing node and the second routing node according to the first target link costs corresponding to all the first links. When a remote SRLG link fails, the application can avoid the risk of sharing an optical layer link by a backup path and a working path, and improve data transmission reliability.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of communication, in particular to a path determination method, a communication device and a computer readable storage medium. BACKGROUND

[0002] With the development of MPLS (Multi-Protocol Label Switching), SR (Segment Routing), 5G and other technologies, the network scale is getting larger and larger, users hope to get faster and more stable Internet services, and operators also put forward higher requirements for the capabilities of bearer network devices, especially in the protection switching scenario of networking environment. In the field of communication technology, optical paths are widely used to transmit information, and if the optical path fails, it will cause the interruption of information transmission and cause great losses. Therefore, the path protection mechanism is born, which creates two "physically separated" paths for each optical path, namely the working path (main path) and the protection path (backup path), to ensure the reliability of optical path transmission services.

[0003] The IETF proposes the concept of SRLG (Shared Risk Link Group). SRLG is a group of links that share the same physical resources. When one member link fails, other member links also have the risk of failure. Therefore, in the networking scenario containing the risk sharing link group, it is necessary to avoid the working path and the protection path from being carried in the same SRLG group.

[0004] Currently, in the related technology, it is impossible to determine whether the fault link (i.e. the working path) and the calculated protection link (i.e. the backup path) belong to the same SRLG group, so it is impossible to provide stable and reliable protection for service transmission. SUMMARY

[0005] The main purpose of the present application is to provide a path determination method, a communication device and a computer readable storage medium, which aims to solve the technical problem of how to avoid the backup path and the working path sharing the risk of optical layer links as much as possible when facing the failure of a remote SRLG link.

[0006] To achieve the above purpose, the present application provides a path determination method applied to a first routing node in an SR network, the method comprising:

[0007] obtaining link state advertisement information of all first links between the first routing node and a second routing node, the link advertisement information of the first link comprising shared risk link group SRLG information of the first link;

[0008] determine second links from all the first links according to SRLG information of the first links, the second links being links of all the first links having the same SRLG information as the first routing node;

[0009] adjust actual link costs of all the second links by a preset increase to obtain first target link costs corresponding to all the first links;

[0010] determine a rerouting recovery path between the first routing node and the second routing node according to the first target link costs corresponding to all the first links.

[0011] In addition, to achieve the above object, the present application further provides a path determination method, comprising:

[0012] obtain link state advertisement information of all first links between a first routing node and a second routing node, the link advertisement information of the first links comprising shared risk link group (SRLG) information of the first links;

[0013] determine second links from all the first links according to SRLG information of the first links, the second links being links of all the first links having the same SRLG information as the first routing node;

[0014] eliminate the second links from all the first links to obtain candidate links of the first links except the second links;

[0015] determine a rerouting recovery path between the first routing node and the second routing node according to actual link costs corresponding to all the candidate links.

[0016] In addition, to achieve the above object, the present application further provides a communication device, comprising a processor and a memory, the memory storing programs or instructions executable on the processor, the programs or instructions being executed by the processor to implement the path determination method according to any one of the above.

[0017] In addition, to achieve the above object, the present application further provides a computer readable storage medium, the computer readable storage medium storing programs or instructions, the programs or instructions being executed by a processor to implement the path determination method according to any one of the above.

[0018] The application provides a path determination method, a communication device and a computer readable storage medium. The technical scheme of the embodiment of the application is as follows: link state advertisement information of all first links between a first routing node and a second routing node is acquired, the link advertisement information of the first links includes shared risk link group (SRLG) information of the first links, and a second link is determined from all the first links according to the SRLG information of the first links, the second link being a link identical to the SRLG information of the first routing node in all the first links, then the actual link cost of all the second links is adjusted by a preset increase to obtain first target link costs corresponding to all the first links, and a rerouting recovery path between the first routing node and the second routing node is determined according to the first target link costs corresponding to all the first links, so that the TI-LFA (Topology independent Loop-free alternate) can calculate a protection path based on a new link cost network topology (i.e., a network topology obtained after the actual link cost of all the second links is adjusted by the preset increase) when calculating a path, so as to facilitate calculation of a link cost and a globally optimal path with the minimum cost for switching, and thus the data transmission reliability can be improved when facing a remote SRLG link failure.

[0019] Compared with the manner of reducing the priority of the backup path in the related art when the out interface of the calculated backup path and the out interface of the primary path belong to the same SRLG group, the embodiment of the application can solve the problem that the TI-LFA cannot effectively cover a remote SRLG link failure when calculating a backup protection path, that is, the embodiment of the application not only covers the calculation and implementation of a protection scheme for a local failure in a complex networking scenario containing an SRLG group, but also supports the calculation and implementation of a protection scheme for a remote failure, thereby supporting all failure scenarios in the complex networking scenario containing the SRLG group, so that the protection path bypasses a link containing the same SRLG as the primary path, and thus reliable protection is provided for data operation of an operator service. BRIEF DESCRIPTION OF DRAWINGS

[0020] The accompanying drawings, which are incorporated into and form a part of the specification, illustrate an embodiment consistent with the application and, together with the specification, serve to explain the principles of the application.

[0021] In order to more clearly illustrate the technical solutions in the embodiments or the prior art, the accompanying drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, for those skilled in the art, other drawings can also be obtained based on these drawings without creative labor.

[0022] Figure 1 This is a flowchart illustrating the first embodiment of the path determination method of this application;

[0023] Figure 2 This is a flowchart illustrating the second embodiment of the path determination method of this application;

[0024] Figure 3 IP network topology diagram for Layer 3 device connections with SRLG deployed;

[0025] Figure 4 for Figure 3 A schematic diagram of the working path before the remote fault fast rerouting function is enabled;

[0026] Figure 5 In response to Figure 3 The rerouting recovery path map is calculated based on the conventional TI-LFA algorithm.

[0027] Figure 6 For the purposes of this application's embodiments Figure 3 A network topology diagram based on link cost adjustments;

[0028] Figure 7 For the purposes of this application's embodiments Figure 3 The rerouting recovery path diagram calculated after enabling the remote fault fast rerouting function;

[0029] Figure 8 This is a schematic diagram of the hardware operating environment involved in the communication device in this embodiment.

[0030] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0031] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0032] Currently, a relevant solution is to reduce the priority of a backup path when calculating the backup protection path, if the out interface of the calculated backup path and the out interface of the primary path belong to the same group of risk sharing link groups, so as to avoid the case of simultaneous failure of the primary and backup paths and protection failure. However, this solution can only solve the local direct connection scenario, that is, the case where the fault link is directly connected to the node for protection calculation. When the fault link is not directly connected to the calculation node, the calculation node can sense the fault, but cannot determine whether the fault link (that is, the working path) and the calculated protection link (that is, the backup path) belong to the same SRLG group, so as to provide stable and reliable protection for service transmission.

[0033] Embodiment one

[0034] Based on this, please refer to Figure 1 The embodiment provides a path determination method, which comprises the following steps:

[0035] Step S100, acquiring link state advertisement information of all first links between a first routing node and a second routing node;

[0036] The link advertisement information of the first link comprises SRLG (Shared Risk Link Group) information of the first link.

[0037] In the embodiment, each routing node (a routing node can be a router or a switch) in an IP (Internet Protocol) network can generate link state advertisement information (LSA, Link-State Advertisement). The LSA advertisement lists all links or interfaces of the IP network, and indicates their states and the outgoing cost in each link direction, as well as all known OSPF (Open Shortest Path First) neighbors on the link. These LSA advertisements are often only flooded within the area where they originate. The IP network can comprise a normal IP network and an SR (Segment Routing) network.

[0038] It should be noted that the path determination method of the embodiment of the application can be applied to any routing node in an IP network topology, wherein the routing node to which the path determination method is applied is the first routing node (that is, the execution subject). Of course, the path determination method of the embodiment of the application can also be applied to a central control device (the central control device stores a program for implementing the path determination method of the embodiment of the application, and the central control device can also be referred to as an upper control device or an upper computer) independent of the routing nodes in the IP network topology, wherein the central control device is the execution subject.

[0039] It is known that the SRLG information is flooding information announced by each routing node. In an embodiment, the path determination method of the present embodiment is applied to a first routing node, and the SRLG information can be flooding information announced by a second routing node or flooding information announced by an intermediate routing node between the first routing node and the second routing node. In another embodiment, the path determination method of the present embodiment is applied to a control device independent of each routing node in an IP network topology, and the SRLG information can be flooding information announced by the first routing node, flooding information announced by the second routing node, or flooding information announced by an intermediate routing node between the first routing node and the second routing node.

[0040] It is known to those skilled in the art that the SRLG (Shared Risk Link Group) information refers to a group of links that share the same physical resources, and when one member link fails, other member links also have the risk of failure. Therefore, in a networking scenario containing SRLG, it is necessary to avoid working paths and protection paths from being carried in the same SRLG group.

[0041] In the present embodiment, the first routing node is a starting routing node or a source routing node, and the second routing node is a destination routing node or a tail routing node. The first routing node is an upstream routing node of the second routing node. The first routing node to the second routing node further includes a preset number of intermediate routing nodes, that is, the path determination method of the present embodiment is applied to a networking environment containing SRLG with at least three layers of routing device hierarchy, and can be deployed in protection scenarios such as IP FRR (Internet Protocol Fast Reroute), TI-LFA (Topology-independent Loop-free alternate), LFA (Loop-free alternate), etc. based on SRLG.

[0042] Exemplarily, the link announcement information of the first link can further include an actual link cost of the first link.

[0043] After step S100, step S200 is performed, and a second link is determined from all the first links according to the SRLG information of the first link.

[0044] Among them, the second link is a link with the same SRLG information as the first routing node among all the first links.

[0045] Step S300, preset increasing adjustment is made to the actual link cost of all the second links, to obtain the first target link cost corresponding to all the first links;

[0046] For example, in step S300, preset increasing adjustment is made to the actual link cost of all the second links, to obtain the first target link cost corresponding to all the first links, including:

[0047] Step A10, preset increasing adjustment is made to the actual link cost of all the second links, to obtain the second target link cost corresponding to all the second links after the preset increasing adjustment;

[0048] Step A20, according to the second target link cost of all the second links and the actual link cost of the links other than the second links in the first links, the first target link cost corresponding to all the first links is obtained.

[0049] In this embodiment, preset increasing adjustment is made to the actual link cost of all the second links, and then the link cost and the minimum optimization target are combined, so that the concept of a penalty link cost bound with SRLG is introduced innovatively, and TI-LFA (Topology independent Loop-free alternate) is used to calculate the protection path based on the new link cost network topology (i.e., the network topology obtained after preset increasing adjustment is made to the actual link cost of all the second links) when calculating the path, so that the global optimal path with the minimum link cost can be calculated for switching, and the network performance is effectively improved.

[0050] After step S300, step S400 is performed, and the rerouting recovery path between the first routing node and the second routing node is determined according to the first target link cost corresponding to all the first links.

[0051] In this embodiment, the link cost and the minimum reachable path from the first routing node to the second routing node (formed by concatenating part of the first links) can be determined from the first target link cost corresponding to all the first links, as the optimal protection path, and then the optimal protection path selected based on the minimum link cost principle is used to determine the rerouting recovery path between the first routing node and the second routing node, so that the risk of sharing the optical layer link of the working path and the backup path can be effectively avoided, the network performance is improved, and a method for solving the failure of the topology-independent redundant alternative protection algorithm caused by the failure of the far end of the risk-sharing link group is provided, so that the router node is more accurate when performing topology-independent redundant alternative protection calculation, and the protection path bypasses the link containing the same SRLG as the main path.

[0052] The application provides a path determination method, a communication device and a computer readable storage medium. The technical scheme of the embodiment of the application is as follows: link state advertisement information of all first links between a first routing node and a second routing node is acquired, the link advertisement information of the first links includes shared risk link group (SRLG) information of the first links, and a second link is determined from all the first links according to the SRLG information of the first links, the second link being a link identical to the SRLG information of the first routing node in all the first links, then the actual link cost of all the second links is adjusted by a preset increase to obtain first target link costs corresponding to all the first links, and a rerouting recovery path between the first routing node and the second routing node is determined according to the first target link costs corresponding to all the first links, so that the TI-LFA (Topology independent Loop-free alternate) performs protection path calculation based on a new link cost network topology (i.e., a network topology obtained after the actual link cost of all the second links is adjusted by the preset increase) when calculating a path, so as to facilitate calculation of a link cost and a globally optimal path with the minimum cost for switching, and thus the data transmission reliability can be improved when facing a remote SRLG link failure.

[0053] Compared with the manner of reducing the priority of the backup path in the related art when the out interface of the calculated backup path and the out interface of the primary path belong to the same SRLG group, the embodiment of the application can solve the problem that the TI-LFA cannot effectively cover a remote SRLG link failure when calculating a backup protection path, that is, the embodiment of the application not only covers local failure protection scheme calculation and implementation in a complex networking scenario containing an SRLG group, but also supports remote failure protection scheme calculation and implementation, thereby realizing support for all failure scenarios in a complex networking scenario containing an SRLG group, so that the protection path bypasses a link containing the same SRLG as the primary path, and thus reliable protection is provided for data operation of an operator service.

[0054] Exemplarily, before the acquisition of the link state advertisement information of all the first links between the first routing node and the second routing node, the method further includes:

[0055] Step B10 enables a remote failure fast rerouting function.

[0056] In the embodiment, a fast reroute switch for remote SRLG protection (fast-reroute remote-SRLG-protection enable / disable) is configured to enable the fast reroute function for remote SRLG protection. For example, a fast reroute switch for remote SRLG protection is configured on the first routing node (i.e., the source routing node) or the control device to control whether to enable the fast reroute function for remote SRLG protection, so that the operator can enable or disable the fast reroute function for remote SRLG protection as needed. It should be noted that the fast reroute function for remote SRLG protection refers to that when a fault is detected at the physical layer or the link layer, a backup link is immediately enabled to forward a packet. That is, when a fault is detected at the physical layer or the link layer, the first routing node (i.e., the source routing node) or the control device re-computes a route based on the path determination method of the embodiment (e.g., steps S100 to S300) to complete route convergence (i.e., a recovery path is calculated).

[0057] In the embodiment, after the fast reroute function for remote SRLG protection is enabled, step S100 of the path determination method of the embodiment is performed to obtain link state advertisement information of all first links between the first routing node and the second routing node, so that the backup path (i.e., the recovery path) can be calculated in advance when the main link is available by enabling the fast reroute function for remote SRLG protection, and the IP network system can quickly respond to the link fault, the backup route is directly enabled for data forwarding, and the service is quickly restored to normal.

[0058] In a possible implementation, the step of presetting an increase adjustment on the actual link cost of all the second links includes:

[0059] In step C10, the actual link cost of all the second links is respectively increased by a preset link cost penalty value.

[0060] In the embodiment, the preset link cost penalty value can be set by a person skilled in the art according to actual conditions, and the embodiment is not limited in detail. The preset link cost penalty value is set according to the requirement of better avoiding the risk of sharing the optical layer link by the backup path and the working path. It is easy to understand that the preset link cost penalty value has certain requirements and cannot be too small, otherwise the protection path calculated by the device based on the new link cost protocol topology (i.e., the IP network topology after the preset increase adjustment on the actual link cost of all the second links) may pass through the link identified by the protection SRLG, which leads to the risk of sharing the optical layer link by the backup path and the working path, and the desired effect cannot be achieved.

[0061] The embodiment increases the actual link cost of all second links by a preset link cost penalty value respectively, and combines the link cost and the minimum as an optimization target, so that the application embodiment innovatively introduces the concept of a penalty link cost bound with an SRLG. When the TI-LFA (Topology independent Loop-free alternate) calculates a route, the TI-LFA calculates a protection path based on a new link cost network topology (i.e., a network topology obtained by preset increasing adjustment of the actual link cost of all second links), so that a globally optimal path with the minimum link cost can be calculated for switching, and thus the risk of sharing an optical layer link by a backup path and a working path can be avoided as much as possible when a remote SRLG link fails, thereby providing strong protection for stable transmission of services of a communication operator.

[0062] In a possible implementation, the step of determining the re-routing recovery path between the first routing node and the second routing node according to the first target link cost corresponding to all the first links comprises:

[0063] Step D10, determining a total link cost of each reachable path between the first routing node and the second routing node according to the first target link cost of all the first links, the total link cost being a sum of the first target link cost corresponding to all the first links constituting the reachable path.

[0064] Step D20, determining the reachable path with the minimum total link cost as the re-routing recovery path between the first routing node and the second routing node.

[0065] In the embodiment, the reachable path is a link path constituted by a series of first links between the first routing node and the second routing node, the source routing node (or head node) of the reachable path being the first routing node, and the tail routing node (or tail node) of the reachable path being the second routing node.

[0066] It can be understood that each reachable path has a corresponding total link cost. For example, the total link cost corresponding to the reachable path A is a sum of the first target link cost corresponding to all the first links constituting the reachable path A. The total link cost corresponding to the reachable path B is a sum of the first target link cost corresponding to all the first links constituting the reachable path B.

[0067] The embodiment determines the total link cost of each reachable path between the first routing node and the second routing node according to the first target link cost of all the first links, and determines the reachable path with the minimum total link cost as the reroute recovery path between the first routing node and the second routing node, so that the reachable path with the minimum sum of link costs is selected as the reroute recovery path from the reachable paths based on the adjusted network topology (i.e. the network topology obtained after the preset increase adjustment is performed on the actual link costs of all the second links), thereby effectively avoiding the risk of sharing the optical layer link of the working path and the backup path, and further improving the communication performance of the IP network system. In addition, the embodiment uses the link cost to represent the cost required to use each link, and takes the minimum cost as the optimization goal, thereby overcoming the problem that the backup path is blindly selected without considering whether the path is the optimal path, so that the reroute recovery path selected by the embodiment is the globally optimal path except the main path.

[0068] In a possible implementation, the step of determining the second link from all the first links according to the SRLG information of the first link includes:

[0069] Step E10, matching the link with the same SRLG information as the SRLG information of the first routing node from all the first links according to the SRLG information of the first link;

[0070] Step E20, determining the matched first link as the second link.

[0071] The embodiment matches the link with the same SRLG information as the SRLG information of the first routing node from all the first links according to the SRLG information of the first link, and determines the matched first link as the second link, so as to accurately screen the link that shares the optical layer link risk with the working path (i.e. the main link), thereby facilitating the subsequent preset increase adjustment on the actual link cost of the link (i.e. the second link) that shares the optical layer link risk with the working path, so that the protection path (i.e. the reroute recovery path) calculated during the fault reroute calculation can bypass the link that shares the same SRLG with the main path, thereby providing reliable protection for the data operation of the operator service.

[0072] Further, in order to assist understanding of the technical principles of the embodiments of the application, a specific embodiment is listed, which includes:

[0073] The specific embodiment is applied to a three-layer device, including but not limited to a bearer router or a switch with a device level of three layers. The path determination method of the specific embodiment includes:

[0074] Firstly, a preset link cost penalty value P is set for the risk sharing link group srlg1 (the link cost penalty value P has certain requirements and cannot be too small, otherwise the protection path calculated by the device based on the new link cost protocol topology may pass through the link identified by the protection srlg1, resulting in failure to achieve the expected effect), and a remote srlg failure fast reroute switch is set to enable the remote failure fast reroute function.

[0075] In the specific embodiment, as shown in Figure 3 , Figure 3 is an IP network topology diagram connected by a three-layer device deployed with SRLG. Among them, R1 is a first routing node, R6 is a second routing node, R2, R3, R4 and R5 are intermediate routing nodes. Among them, R1 sets the preset link cost penalty value to 50 (SRLG 1 admin-weight 50), and sets a remote SRLG failure fast reroute switch (fast-reroute remote-SRLG-protection enable / disable) to control whether to enable the remote failure fast reroute function, facilitating the operator customer to start and stop as needed.

[0076] Please refer to Figure 4 , Figure 4 is Figure 3 the working path diagram before the remote failure fast reroute function is enabled. Please refer to Figure 5 , Figure 5 is the reroute recovery path diagram calculated based on the conventional TI-LFA algorithm in Figure 3 , the protection path is R1—R2—R4—R5—R5, which does not bypass the link belonging to SRLG1, and there is still a risk of sharing optical layer links between the standby path and the working path when facing remote SRLG link failure.

[0077] Secondly, after the preset link cost penalty value is configured and the remote failure fast reroute function is enabled at the SRLG network head node (i.e. the first routing node R1), each intermediate routing node floods the LSA (Link-State Advertisement, Link State Advertisement) of the SRLG information (i.e. the SRLG information of the first link) and the link cost information (i.e. the actual link cost of the first link) to R1;

[0078] After R1 is configured with the preset link cost penalty value and the remote failure fast reroute switch is turned on, the intermediate routing nodes R3, R4 and R5 configured with SRLG1 will flood the LSA carrying the legacy SRLG tlv to R1, which carries the SRLG information and the link cost information.

[0079] The third step is that after R1 receives the LSA message, it identifies the information in the LSA and matches it with its own configured SRLG link cost penalty value. Then, it adds the link cost value in the original LSA to its own configured SRLG penalty value to obtain the new cost value.

[0080] After receiving an LSA message describing link R5-R6 carrying a legacy SRLG tlv (Tag Length Value), R1 identifies the SRLG information in the LSA as 1, which matches its own configured SRLG link cost penalty SRLG 1admin-weight 50. R1 then adds the original link cost 5 in the LSA to its own configured SRLG penalty value 50, resulting in a new cost value of 55 representing the link cost of R5-R6. Similarly, this applies to links R1-R3 (cost 1), R3-R5 (cost 1), R4-R5 (cost 5), and R5-R6 (cost 5). The corresponding link cost values ​​obtained by adding the configured SRLG penalty value 50 are: R1-R3 (cost 51), R3-R5 (cost 51), R4-R5 (cost 55), and R5-R6 (cost 55).

[0081] In the fourth step, the SRLG network head node R1, based on the new link cost value, completes the calculation of the topology-independent acyclic redundancy alternative protection path and obtains the new protection path.

[0082] like Figure 6 As shown, device R1 then calculates the topology-independent acyclic redundancy alternative protection path based on the network topology graph composed of the new link cost values. Figure 7 As shown, Figure 7 For the purposes of this application's embodiments Figure 3 The calculated rerouting recovery path map after enabling the remote fault fast rerouting function shows a protection path of R1—R2—R4—R6, which bypasses the link belonging to SRLG1. When facing remote SRLG link failures, it effectively avoids the risk of the backup path and working path sharing the optical layer link.

[0083] In addition, there are LFA protection path calculation scenarios that include SRLG, and the protocols running between devices include, but are not limited to, OSPF (Open Shortest Path First) and ISIS (Intermediate System-to-Intermediate System).

[0084] The embodiment provides a method capable of solving the problem that a topology-independent redundant replacement protection algorithm fails due to remote failure of a risk-sharing link group, so that a router node is more accurate when performing topology-independent redundant replacement protection calculation, and a protection path (i.e., a re-routing recovery path) bypasses a link belonging to the same SRLG as a main path, thereby providing reliable protection for an operator service.

[0085] In addition, in addition to introducing a punitive link cost configured in combination with a link configured with an srlg parameter to solve the problem of TI-LFA protection failure due to remote failure of the srlg, the method of removing the link configured with the same srlg parameter from a network protocol topology can also solve the above problem, and details are not described herein again, and reference can be made to Embodiment Two.

[0086] It should be noted that the details described in the embodiment are only used to help understand the technical concept of the application, and do not constitute a limitation on the application, and more forms of simple transformation based on the technical concept of the application should be within the protection scope of the application.

[0087] Embodiment Two

[0088] Based on the first embodiment of the application, in another embodiment of the application, the same or similar content as the above embodiment one can be referred to the above description, and details are not described herein again. On this basis, please refer to Figure 2 The embodiment further provides a path determination method, and the method comprises the following steps:

[0089] In step S500, link state advertisement information of all first links between a first routing node and a second routing node is acquired.

[0090] The link advertisement information of the first link comprises SRLG information of the first link.

[0091] In the embodiment, each routing node (one routing node can be a router or a switch) in an IP (Internet Protocol) network can generate link state advertisement information (LSA, Link-State Advertisement). The LSA advertisement lists all links or interfaces of the router, and indicates the states of the links or interfaces and the outgoing cost in each link direction, and all known OSPF (Open Shortest Path First) neighbors on the link. The LSA advertisement is often only flooded and diffused within the area where it is originated. The IP network can comprise a normal IP network and an SR (Segment Routing) network.

[0092] It should be noted that the path determination method of the embodiments of the present application can be applied to any routing node in the IP network topology, wherein the routing node to which the path determination method is applied is the first routing node (i.e. the execution subject). Of course, the path determination method of the embodiments of the present application can also be applied to a central control device (which can also be referred to as an upper control device or an upper computer) independent of the routing nodes in the IP network topology, wherein the central control device stores a program for implementing the path determination method of the embodiments of the present application, and the central control device is also the execution subject.

[0093] It can be known that the SRLG information is flooding information announced by each routing node. In an embodiment, the path determination method of the embodiments of the present application is applied to the first routing node, and the SRLG information can be flooding information announced by the second routing node, or flooding information announced by an intermediate routing node between the first routing node and the second routing node. In another embodiment, the path determination method of the embodiments of the present application is applied to a central control device independent of the routing nodes in the IP network topology, and the SRLG information can be flooding information announced by the first routing node, flooding information announced by the second routing node, or flooding information announced by an intermediate routing node between the first routing node and the second routing node.

[0094] It can be known by those skilled in the art that the SRLG (Shared Risk Link Group) information refers to a group of links sharing the same physical resource, and when one member link fails, other member links also have the risk of failure. Therefore, in a networking scenario containing the SRLG, it is necessary to avoid that the working path and the protection path are carried in the same SRLG.

[0095] In the embodiment, the first routing node is a starting routing node or a source routing node, and the second routing node is a destination routing node or a tail routing node. The first routing node is an upstream routing node of the second routing node. The first routing node to the second routing node further includes a preset number of intermediate routing nodes, that is, the path determination method of the embodiments of the present application can be applied to a networking environment containing SRLG with at least three layers of routing device levels, and can be deployed to IP FRR, TI-LFA, LFA and other protection scenarios based on SRLG.

[0096] Exemplarily, the link announcement information of the first link can further include an actual link cost of the first link.

[0097] After step S500, step S600 is performed, wherein a second link is determined from all the first links according to the SRLG information of the first link.

[0098] The second link is a link of all the first links having the same SRLG information as the first routing node.

[0099] Step S700: removing the second link from all the first links to obtain candidate links of the first links except the second link.

[0100] The candidate link refers to other first links except the second link of all the first links.

[0101] In the embodiment, the second link is removed from all the first links, so that the link configured with the same SRLG parameter is creatively removed from the networking protocol topology, that is, the pruning operation is performed on the network topology of the IP network, and a new network topology obtained after the second link is removed (in the new network topology, only the candidate link is left between the first routing node and the second routing node) is obtained. When the TI-LFA (Topology independent Loop-free alternate, topology independent loop-free alternate) calculates a route, the new link cost networking (that is, the network topology obtained after the second link is removed) is used to calculate a protection path, so that the link cost and the global optimal path with the minimum cost are calculated for switching, and the network performance is effectively improved.

[0102] Step S800: determining a rerouting recovery path between the first routing node and the second routing node according to actual link costs corresponding to all the candidate links.

[0103] The application provides a path determination method, a communication device and a computer readable storage medium. The technical scheme of the embodiment of the application is as follows: link state advertisement information of all first links between a first routing node and a second routing node is acquired, the link advertisement information of the first links includes shared risk link group (SRLG) information of the first links, a second link is determined from all the first links according to the SRLG information of the first links, the second link is a link in all the first links that has the same SRLG information as the first routing node, the second link is removed from all the first links, candidate links in the first links except the second link are obtained, a rerouting recovery path between the first routing node and the second routing node is determined according to actual link costs corresponding to all the candidate links, and TI-LFA (Topology independent Loop-free alternate) is used to calculate a protection path based on a new link cost network topology (i.e., a network topology obtained after the second link is removed) when a path is calculated, so that a link cost and a globally optimal path with the minimum cost can be calculated for switching, and therefore, when a remote SRLG link fault occurs, the backup path and the working path can be prevented from sharing an optical layer link risk as much as possible, and data transmission reliability is improved.

[0104] Compared with the way of reducing the priority of the backup path in the related art when the out interface of the calculated backup path and the out interface of the primary path belong to the same SRLG group, the embodiment of the application can solve the problem that TI-LFA cannot effectively cover a remote SRLG link fault when a backup protection path is calculated, that is, the embodiment of the application not only covers local failure protection scheme calculation and implementation in a complex networking scenario containing an SRLG group, but also supports remote failure fault scenario protection scheme calculation and implementation, thereby realizing support for all failure scenarios in a complex networking scenario containing an SRLG group, so that the protection path bypasses a link containing the same SRLG as the primary path, and further provides reliable protection for data operation of an operator service.

[0105] Exemplarily, before the acquiring of the link state advertisement information of all the first links between the first routing node and the second routing node, the method further includes:

[0106] Step F10 enables a remote failure fast rerouting function.

[0107] In the embodiment, a fast reroute switch for remote SRLG protection (fast-reroute remote-SRLG-protection enable / disable) is configured to enable the fast reroute function for remote SRLG protection. For example, a fast reroute switch for remote SRLG protection is configured on the first routing node (i.e., the source routing node) or the control device to control whether to enable the fast reroute function for remote SRLG protection, so as to facilitate the operator customer to enable and disable the fast reroute function for remote SRLG protection as needed. It should be noted that the fast reroute function for remote SRLG protection refers to that when a fault is detected at the physical layer or the link layer, a backup link is immediately enabled to forward a packet. That is, when a fault is detected at the physical layer or the link layer, the first routing node (i.e., the source routing node) or the control device re-computes a route based on the path determination method (for example, steps S100 to S300) of the embodiment to complete route convergence (i.e., a reroute recovery path is calculated).

[0108] According to the embodiment, after the fast reroute function for remote SRLG protection is enabled, step S100 of the path determination method is executed to obtain link state advertisement information of all first links between the first routing node and the second routing node, so that the backup path (i.e., the reroute recovery path) is calculated in advance when the main link is available, the IP network system can quickly respond to the link fault, and the backup route is directly enabled to forward data, so that the service is quickly restored to normal.

[0109] In a possible implementation, the step of determining the reroute recovery path between the first routing node and the second routing node according to the actual link cost corresponding to each candidate link includes:

[0110] In step H10, a total link cost of each reachable path between the first routing node and the second routing node is determined according to the actual link cost corresponding to each candidate link, and the total link cost is the sum of the actual link cost corresponding to all candidate links constituting the reachable path.

[0111] In step H20, the reachable path with the minimum total link cost is determined as the reroute recovery path between the first routing node and the second routing node.

[0112] In the embodiment, the reachable path is a link path constituted by partial candidate links between the first routing node and the second routing node, the source routing node (or head node) of the reachable path is the first routing node, and the tail routing node (or tail node) of the reachable path is the second routing node.

[0113] It can be understood that each reachable path has its corresponding total link cost, for example, the total link cost corresponding to the reachable path A is the sum of the actual link costs corresponding to all candidate links constituting the reachable path A. The total link cost corresponding to the reachable path B is the sum of the actual link costs corresponding to all candidate links constituting the reachable path B.

[0114] The embodiment determines the total link cost of each reachable path between the first routing node and the second routing node according to the actual link cost of all candidate links, and determines the reachable path with the minimum total link cost as the reroute recovery path between the first routing node and the second routing node, so that the reachable path with the minimum sum of link costs is selected as the reroute recovery path from each reachable path based on the adjusted network topology (i.e. the network topology obtained after the second link is removed), thereby effectively avoiding the risk of sharing the optical layer link of the working path and the backup path, and further improving the communication performance of the IP network system. In addition, the embodiment uses link cost to represent the cost required to use each link, and takes the minimum cost as the optimization goal, which overcomes the problem of blindly selecting a backup path without considering whether the path is the best path, so that the reroute recovery path selected by the embodiment is the globally optimal path except the main path.

[0115] In a possible implementation, the step of determining the second link from all the first links according to the SRLG information of the first link includes:

[0116] Step I10, matching the link with the same SRLG information as the SRLG information of the first routing node from all the first links according to the SRLG information of the first link;

[0117] Step I20, determining the matched first link as the second link.

[0118] The embodiment matches the link with the same SRLG information as the SRLG information of the first routing node from all the first links according to the SRLG information of the first link, and determines the matched first link as the second link, so as to accurately filter out the link sharing the optical layer link risk with the working path (i.e. the main link), and facilitate subsequent removal of the link sharing the optical layer link risk with the working path (i.e. the second link) from the first link, so that the protection path (i.e. the reroute recovery path) calculated in the fault reroute calculation can bypass the link containing the same SRLG as the main path, thereby providing reliable protection for the data operation of the operator service.

[0119] Embodiment three

[0120] The embodiment of the present application provides a communication device, the communication device comprising: at least one processor; and a memory connected with the at least one processor in communication; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the path determination method in the embodiment one.

[0121] Reference is made below Figure 8 which shows a structural schematic diagram of a communication device suitable for implementing the embodiments of the present disclosure. As Figure 8 shown, the communication device can include a processing device 1001 (for example, a central processor, a graphics processor, etc.), which can perform various appropriate actions and processes according to programs stored in a read-only memory (ROM 1002) or loaded from a storage device into a random access memory (RAM 1004). In the RAM 1004, various programs and data required for the operation of the communication device are also stored. The processing device 1001, the ROM 1002, and the RAM 1004 are connected to each other through a bus 1005. An input / output (I / O) interface is also connected to the bus 1005.

[0122] Generally, the following systems can be connected to the I / O interface 1006: an input device 1007 including, for example, a touch screen, a touch pad, a keyboard, a mouse, an image sensor, a microphone, etc.; an output device 1008 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 can allow the communication device to communicate with other devices wirelessly or by wire to exchange data. Although the communication device with various systems is shown in the figure, it should be understood that all the shown systems are not required to be implemented or possessed. More or less systems can be alternatively implemented or possessed.

[0123] In particular, according to the embodiments of the present disclosure, the processes described above with reference to the flowcharts can be implemented as a computer software program. For example, the embodiments of the present disclosure include a computer program product comprising a computer program carried on a computer readable medium, the computer program containing program codes for executing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network through the communication device, or installed from the storage device 1003, or installed from the ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the methods of the embodiments of the present disclosure are performed.

[0124] The communication device provided by the present application can solve the technical problem of how to avoid the risk of the standby path and the working path sharing the optical layer link when facing the remote SRLG link failure, and improve the data transmission reliability. Compared with the prior art, the communication device provided by the embodiment of the present application has the same beneficial effects as the path determination method provided by the above-mentioned embodiment, and other technical features in the communication device are the same as the features disclosed in the above-mentioned embodiment method, which will not be repeated here.

[0125] It should be understood that parts of the present disclosure can be realized by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0126] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

[0127] Embodiment four

[0128] The embodiment of the present application provides a computer readable storage medium having computer readable program instructions stored thereon, and the computer readable program instructions are used to execute the path determination method in the above-mentioned embodiment.

[0129] The computer readable storage medium provided by the embodiment of the present application may, for example, be a U disk, but is not limited to an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, system or device, or any combination of the above. More specific examples of computer readable storage media can include, but are not limited to: electrical connections with one or more conductive wires, portable computer disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), optical fibers, portable compact disk read-only memories (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the above. In the present embodiment, the computer readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, system or device. The program code contained on the computer readable storage medium can be transmitted by any appropriate medium, including but not limited to: electrical wires, optical cables, RF (radio frequency), etc., or any suitable combination of the above.

[0130] The above-mentioned computer readable storage medium can be contained in the communication device; or can exist separately without being assembled into the communication device.

[0131] The computer readable storage medium described above carries one or more programs, when the one or more programs are executed by the communication device, cause the communication device to: acquire link state advertisement information of all first links between a first routing node and a second routing node, the link advertisement information of the first links including shared risk link group (SRLG) information of the first links; determine second links from all the first links according to the SRLG information of the first links, the second links being links of all the first links that have the same SRLG information as the first routing node; preset an increase adjustment on actual link costs of all the second links to obtain first target link costs corresponding to all the first links; and determine a rerouting recovery path between the first routing node and the second routing node according to the first target link costs corresponding to all the first links. Alternatively, the computer readable storage medium described above carries one or more programs, when the one or more programs are executed by the communication device, cause the communication device to: acquire link state advertisement information of all first links between a first routing node and a second routing node, the link advertisement information of the first links including shared risk link group (SRLG) information of the first links; determine second links from all the first links according to the SRLG information of the first links, the second links being links of all the first links that have the same SRLG information as the first routing node; eliminate the second links from all the first links to obtain candidate links of the first links excluding the second links; and determine a rerouting recovery path between the first routing node and the second routing node according to actual link costs corresponding to all the candidate links.

[0132] Computer program code for carrying out operations of the present disclosure can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0133] The computer program product can solve the technical problem of how to avoid the risk of the backup path and the working path sharing the optical layer link as much as possible when facing the remote SRLG link fault, and improve the data transmission reliability. Compared with the prior art, the computer program product provided in the embodiment of the present application has the same beneficial effects as the path determination method provided in the first embodiment or the second embodiment, and details are not described herein.

[0134] The modules described in the embodiments of the present disclosure can be implemented in the form of software or in the form of hardware. In some cases, the name of the module does not constitute a limitation on the module itself.

[0135] The computer readable storage medium provided by the present application stores computer readable program instructions for executing the path determination method described above, and can solve the technical problem of how to avoid the risk of the backup path and the working path sharing the optical layer link as much as possible when facing the remote SRLG link fault, and improve the data transmission reliability. Compared with the prior art, the beneficial effects of the computer readable storage medium provided in the embodiment of the present application are the same as those of the path determination method provided in the first embodiment or the second embodiment, and details are not described herein.

[0136] Embodiment five

[0137] The embodiment of the present application further provides a computer program product, comprising a computer program, which, when executed by a processor, implements the steps of the path determination method as described above.

[0138] The computer program product provided by the present application can solve the technical problem of how to avoid the risk of the backup path and the working path sharing the optical layer link as much as possible when facing the remote SRLG link fault, and improve the data transmission reliability. Compared with the prior art, the beneficial effects of the computer program product provided in the embodiment of the present application are the same as those of the path determination method provided in the first embodiment or the second embodiment, and details are not described herein.

[0139] The above merely preferred embodiments of the present application, and not therefore limit the patent scope of the present application, any equivalent structure or equivalent process transformation using the content of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent processing scope of the present application.

Claims

1. A path determination method, comprising: Obtain the link status announcement information of all first links between the first routing node and the second routing node. The link announcement information of the first links includes the risk-sharing link group (SRLG) information of the first links. Based on the SRLG information of the first link, a second link is determined from all the first links. The second link is the link with the same SRLG information as the first routing node among all the first links. The actual link cost of all second links is pre-increased and adjusted to obtain the first target link cost corresponding to all first links; Based on the first target link cost corresponding to all the first links, the rerouting recovery path between the first routing node and the second routing node is determined.

2. The path determination method as described in claim 1, characterized in that, The step of pre-increasing the actual link cost of all second links to obtain the first target link cost corresponding to all first links includes: The actual link cost of all second links is pre-increased and adjusted to obtain the second target link cost after the pre-increased adjustment of all second links. Based on the second target link cost of all second links and the actual link cost of the other links in the first links besides the second links, the first target link cost corresponding to all first links is obtained.

3. The path determination method as described in claim 1, characterized in that, The step of pre-increasing the actual link cost of all second links includes: Increase the preset link cost penalty value for each of the second links.

4. The path determination method as described in claim 1, characterized in that, The step of determining the rerouting recovery path between the first routing node and the second routing node based on the first target link costs corresponding to all the first links includes: Based on the first target link cost of all the first links, determine the total link cost of each reachable path between the first routing node and the second routing node, wherein the total link cost is the sum of the first target link costs corresponding to all the first links constituting the reachable path; The reachable path with the minimum total link cost is determined as the rerouting recovery path between the first routing node and the second routing node.

5. The path determination method as described in claim 1, characterized in that, Before obtaining the link status advertisement information of all first links between the first routing node and the second routing node, the method further includes: Enable the fast rerouting function for remote failures.

6. The path determination method as described in claim 1, characterized in that, The step of determining the second link from all the first links based on the SRLG information of the first link includes: Based on the SRLG information of the first link, the link with the same SRLG information as the first routing node is matched from all the first links. The first matched link is identified as the second link.

7. The path determination method as described in any one of claims 1 to 6, characterized in that, The link advertisement information for the first link also includes the actual link cost of the first link.

8. A communication device, characterized in that, The communication device includes a processor and a memory, the memory storing programs or instructions that can run on the processor, the programs or instructions being executed by the processor to implement the path determination method as described in any one of claims 1 to 7.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a program or instructions that, when executed by a processor, implement the path determination method as described in any one of claims 1 to 7.

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