Satellite network backup path switching control method and device

Abstract

The invention provides a satellite network backup path switching control method and device, and the method comprises the steps: switching a current original basic routing path into a backup routing path through a local repair node when a flash fault is detected based on a hardware detection module, so as to forward a data packet based on the backup routing path; when a link detection module detects that a flash fault is evolved into a long-term stable fault, a local repair node floods a link state to all nodes of the satellite network, each node calculates to obtain a new basic routing path, and a corresponding original basic routing path is replaced based on each new basic routing path; and the local repair node switches the backup routing path to a new basic routing path corresponding to the local repair node so as to forward the data packet based on the new basic routing path. According to the invention, the traffic forwarding stability of the satellite network under the fault is improved, and the waste of computing resources is reduced.

Description

Technical Field

[0001] The present invention relates to the field of satellite communication technology, and in particular to a satellite network backup path switching control method and device. Background Art

[0002] Satellite communication systems play an irreplaceable role in the integrated network of air, land and sea with their advantages of wide coverage, large scale and no geographical blind spots. However, the changeable and unstable topology of satellite networks in practice leads to relatively high transmission delays in satellite networks, and link failures or node failures are more likely to occur. Link failures or node failures will affect the stability of satellite network traffic transmission; therefore, it is of great significance to improve the existing satellite network fast rerouting solution (FastReRoute, FRR).

[0003] When dealing with link or node failures in satellite networks, a common emergency measure is to quickly adjust the status of physical equipment to restore the underlying transmission network. However, relying solely on such physical adjustments is not enough to ensure reliability, because the network layer often needs to re-plan routes for failure situations; when the satellite network system detects link or node failures through fault detection mechanisms, the routing protocol will use fast rerouting mechanisms to direct traffic to new paths that bypass the fault area.

[0004] Based on the mature practices of ground networks, the rerouting methods in satellite networks can be divided into passive rerouting and active rerouting. Among them, the passive rerouting strategy takes effect after the fault is sensed. This strategy uses the IGP routing protocol to sense the network fault and ensure that the new route is issued only after the topology information of the entire network converges. During the convergence time of several seconds or even minutes, the satellite communication system still cannot guide the traffic to the new path. Compared with passive rerouting, the active rerouting strategy pre-configures backup resources for the traffic before data transmission. Once the satellite node detects an abnormality in the link or adjacent node, it can quickly activate the backup path and guide the traffic to the pre-calculated backup path. However, this strategy also faces challenges: the direct perception of satellite node failure is limited to neighboring nodes, while other non-directly adjacent nodes in the network still need to rely on the convergence mechanism of the IGP protocol to gradually perceive the fault, which is a relatively slow process. In addition, due to the asynchronous update of the network status, some nodes may still forward data based on the old routing information, which may cause routing loops (i.e., the loop-free alternative path LFA problem).

[0005] At present, although the existing satellite fast rerouting mechanism can complete the forwarding of data packets based on the backup path when the link or node fails, the existing satellite fast rerouting mechanism does not classify link failures into stable failures at the second level and flash failures at the millisecond level caused by laser instability, thereby limiting the satellite network's perception of flash failures, reducing the stability of satellite network traffic forwarding under failures, and also causing frequent switching between the basic routing path and the backup routing path, resulting in a waste of onboard computing resources. Therefore, how to improve the stability of satellite network traffic forwarding under failures and reduce the waste of computing resources is a technical problem that needs to be solved urgently. Summary of the invention

[0006] In view of this, an embodiment of the present invention provides a satellite network backup path switching control method and device to eliminate or improve one or more defects in the prior art.

[0007] One aspect of the present invention provides a satellite network backup path switching control method, the method comprising:

[0008] When a flash failure is detected by the hardware detection module, the local repair node switches the current original basic routing path to a backup routing path to forward data packets based on the backup routing path;

[0009] When the link detection module detects that the flash fault evolves into a long-term stable fault, the local repair node floods the link status to all nodes in the satellite network, each of the nodes calculates a new basic routing path, and replaces the corresponding original basic routing path based on each of the new basic routing paths;

[0010] The local repair node switches the backup routing path to a new basic routing path corresponding to the local repair node, so as to forward the data packet based on the new basic routing path.

[0011] In some embodiments of the present invention, before the step of detecting that a flash fault evolves into a long-term stable fault based on the link detection module, the method further includes:

[0012] Determine whether the effective time of the backup routing path reaches the effective preset time;

[0013] When the preset effective time is reached, determining whether the flash fault is repaired;

[0014] When the flash failure is repaired, the local repair node switches the backup routing path to the original basic routing path.

[0015] In some embodiments of the present invention, the method further comprises:

[0016] When the effectiveness time of the backup routing path does not reach the preset effectiveness time, it is determined whether the flash failure evolves into a long-term stable failure.

[0017] In some embodiments of the present invention, the local repair node switches the backup routing path to a new basic routing path corresponding to the local repair node, including:

[0018] It is determined whether the release time of the backup routing path reaches the preset release time. When the preset release time is reached, the local repair node switches the backup routing path to a new basic routing path corresponding to the local repair node.

[0019] In some embodiments of the present invention, the local repair node switches the current original basic routing path to the backup routing path, including:

[0020] The local repair node sets the priority of the backup routing path to be higher than the priority of the original basic routing path.

[0021] In some embodiments of the present invention, replacing the corresponding original basic routing path based on each of the new basic routing paths includes: setting the priority of each of the new basic routing paths to be equal to the priority of the corresponding original basic routing path; and / or,

[0022] The local repair node switches the backup routing path to a new basic routing path corresponding to the local repair node, including:

[0023] The local repair node sets the priority of the corresponding new basic routing path to be higher than the priority of the backup routing path.

[0024] In some embodiments of the present invention, determining whether the effective time of the backup routing path reaches the effective preset time includes: determining whether the effective time of the backup routing path reaches the effective preset time based on the backup path effective timer;

[0025] Determining whether the release time of the backup routing path reaches the preset release time includes: determining whether the release time of the backup routing path reaches the preset release time based on a backup path release timer.

[0026] According to one aspect of the present invention, a satellite network backup path switching control system is also disclosed, the system comprising a processor, a memory and a computer program stored in the memory, the processor is used to execute the computer program, and when the computer program is executed, the system implements the steps of the method described in any of the above embodiments.

[0027] According to another aspect of the present invention, a computer-readable storage medium is disclosed, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method described in any of the above embodiments are implemented.

[0028] According to yet another aspect of the present invention, a computer program product is disclosed, including a computer program, which implements the steps of the method described in any of the above embodiments when executed by a processor.

[0029] The satellite network backup path switching control method and device disclosed in the above embodiment of the present invention, when the fault is detected as a flash fault, the current original basic routing path is switched to the backup routing path. When a long-term stable fault is detected, each node recalculates the corresponding new basic routing path, and further switches the backup routing path to the new basic routing path corresponding to the local repair node. The method determines the switching mode of the routing path based on the type of fault, prevents the frequent switching of the basic routing path and the backup routing path, reduces the waste of on-board computing resources, and avoids the oscillation of business traffic caused by the frequent switching of the primary and backup paths, thereby improving the stability of traffic forwarding in the satellite network under fault conditions.

[0030] In addition to the above, the method further determines whether to switch between the basic routing path and the backup routing path through the effective time of the backup routing path and the release time of the backup routing path. The method further improves the rationality of the switching between the basic routing path and the backup routing path, thereby further improving the stability of the satellite communication system and reducing the waste of computing resources.

[0031] Additional advantages, purposes, and features of the present invention will be described in part in the following description, and will become apparent to those skilled in the art after studying the following, or may be learned from the practice of the present invention. The purposes and other advantages of the present invention may be achieved and obtained by the structures specifically indicated in the specification and the accompanying drawings.

[0032] Those skilled in the art will appreciate that the objectives and advantages that can be achieved with the present invention are not limited to the above specific description, and the above and other objectives that can be achieved by the present invention will be more clearly understood from the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The drawings described herein are used to provide a further understanding of the present invention, constitute a part of this application, and do not constitute a limitation of the present invention. The components in the drawings are not drawn to scale, but are only for illustrating the principles of the present invention. In order to facilitate the illustration and description of some parts of the present invention, the corresponding parts in the drawings may be enlarged, that is, they may become larger relative to other components in the exemplary device actually manufactured according to the present invention. In the drawings:

[0034] Figure 1 The present invention is a flowchart of a satellite network backup path switching control method according to an embodiment of the present application.

[0035] Figure 2 A schematic diagram of a routing path of a satellite network according to an embodiment of the present application.

[0036] Figure 3 This is a flowchart of a satellite network backup path switching control method according to another embodiment of the present application.

[0037] Figure 4 This is a timing diagram of a satellite network backup path switching control method according to an embodiment of the present application.

[0038] Figure 5 A schematic diagram of a node structure of a satellite network according to an embodiment of the present application. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments and the accompanying drawings. Here, the illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0040] It should also be noted that, in order to avoid obscuring the present invention due to unnecessary details, only structures and / or processing steps closely related to the solutions according to the present invention are shown in the accompanying drawings, while other details that are not closely related to the present invention are omitted.

[0041] It should be emphasized that the term “include / comprises” when used herein refers to the presence of features, elements, steps or components, but does not exclude the presence or addition of one or more other features, elements, steps or components.

[0042] It should also be noted here that, unless otherwise specified, the term "connection" in this article can refer not only to a direct connection, but also to an indirect connection with an intermediary, not only to a wired connection, but also to a wireless connection, and the specific connection can be changed based on the actual application scenario.

[0043] In order to better understand the present invention, the terms related to the technical solution are explained as follows:

[0044] PLR (Point of Local Repair) is a device in the network. Its main function is to reduce the impact of network failures on service transmission by quickly switching to a backup path when a network failure occurs. Specifically, when a primary LSP (Label Switched Path) link or node in the network fails, PLR can automatically generate a backup path configuration without manual intervention, thereby ensuring service continuity and network stability.

[0045] SR is a data forwarding protocol designed based on the concept of source routing. It has become the mainstream network architecture of SDN. SR divides the forwarding path into segments and assigns segment identifiers IDs to these segments and forwarding points. A forwarding path can be obtained by arranging the segments and network nodes in order (SegmentList). SR encodes SegmentList in the header and transmits it with the packet. After receiving the data packet, SegmentList is parsed. If the top identifier of SegmentList is the current node, the identifier is popped out; if it is not the current node, ECMP is used to send the data packet to the next point. Based on SR, this application can provide link protection with 100% coverage under single link failure conditions; this application encodes the backup path into a sequenced Segment list, that is, a backup path label stack, to instruct the satellite nodes that receive these data packets to process and forward. Segment, that is, label, is the instruction that the satellite node needs to execute for the received data packet. By combining multiple Segments into an ordered list, the data packet can be guided to any path in the satellite network, which is not affected by the routing protocol or the shortest path. The SR backup path data packet carries the backup path label stack in its header. The node will execute the instructions in the label stack and maintain the label stack itself through three basic operations: push, continue, and next. On the SR backup path, the source node is responsible for converting the basic route data packet into an SR backup path data packet and pushing the SR backup path label; after receiving the data packet, the intermediate node checks the label and forwards it in the SR way; after receiving the data packet, the node at the end of the backup path further converts the data packet into a basic route data packet and forwards the basic route on the satellite.

[0046] In addition, in the satellite fast rerouting mechanism disclosed in the prior art, link failures are not classified into second-level stable failures and millisecond-level flash failures caused by laser instability, thereby limiting the satellite network's ability to perceive flash failures and reducing the stability of satellite network traffic forwarding under flash failures. In view of the defects of this mechanism, it is necessary for us to make full use of the fault detection mechanism, timely perceive flash failures with the help of hardware detection, and capture long-term stable failures through the link fault detection mechanism to prevent business traffic oscillation caused by frequent switching of the main and backup paths, thereby enhancing the satellite network's ability to handle faults. In addition, the solutions supporting on-board routing forwarding in the prior art cannot achieve reasonable switching between the basic path and the backup path. The present application can prevent frequent switching of the main path and the backup path through the synergistic effect of hardware detection and link fault detection, thereby reducing the waste of on-board computing resources; and the present application also further achieves reasonable switching of the basic routing path and the backup routing path by setting a backup path effectiveness timer and a backup path release timer.

[0047] In summary, the satellite network rerouting mechanism based on segmented routing in the prior art has a weak perception of flash failures, which will cause jittery temporary communication interruptions, which is not conducive to the stability of the satellite communication system; at the same time, the prior art does not consider how to smoothly and stably switch between the main path and the backup path, which easily leads to frequent switching of the main and backup paths, thereby causing unnecessary waste of on-board computing resources. In order to solve the above series of problems existing in the prior art, the present application discloses a satellite network backup path switching control method and device.

[0048] It should be understood that the satellite network backup path switching control method and device of the present application are used for intersatellite links. Intersatellite links refer to links used for communication between satellites, also known as interstellar links or cross links (Crosslink). Information transmission and exchange between satellites can be achieved through intersatellite links. Multiple satellites are interconnected through intersatellite links to form a space communication network with satellites as exchange nodes.

[0049] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the accompanying drawings, the same reference numerals represent the same or similar components, or the same or similar steps.

[0050] Figure 1 FIG. 1 is a flow chart of a satellite network backup path switching control method according to an embodiment of the present application. Figure 1 As shown, the method at least includes steps S10 to S30.

[0051] Step S10: When a flash failure is detected by the hardware detection module, the local repair node switches the current original basic routing path to a backup routing path to forward data packets based on the backup routing path.

[0052] The backup routing path mentioned in this step needs to be calculated before the failure occurs, and the path needs to be saved on the satellite; when the failure is detected, the backup path routing table entry is enabled to guide the basic routing message to the pre-calculated SR backup routing path. On the SR backup routing path, the satellite nodes can be divided into PLR nodes (local repair nodes), intermediate nodes, and stack bottom nodes according to different control and forwarding behaviors. Before detecting the failure, the PLR ​​node pre-calculates the backup routing path under the failure of the link around itself; in order to realize the table lookup forwarding of the basic route, the PLR, as the head node of the SR backup path, needs to add the ability to direct to the SR backup path table entry when a failure is encountered during the table lookup forwarding process of the basic routing table, that is, add a backup routing table entry in the IP routing table, with a lower priority than the basic routing table entry of the original destination address, and use the virtual port of the backup routing table entry to guide the traffic to the SR backup routing path.

[0053] The flash failure can be specifically a millisecond-level failure, that is, the PLR ​​node detects the flash failure through a hardware detection module with millisecond-level accuracy, and the PLR ​​activates the SR backup routing path, that is, switches the current original basic routing path to the backup routing path, thereby directing the traffic to the virtual port of the backup routing path. Exemplarily, the local repair node switches the current original basic routing path to the backup routing path, which may specifically include: the local repair node sets the priority of the backup routing path to be higher than the priority of the original basic routing path; that is, when the PLR ​​activates the SR backup routing path, it increases the priority of the routing table entry of the backup routing path in the basic routing table to make it higher than the table entry of the basic routing path; this operation only modifies the table entry priority of the backup routing path affected by the fault, and does not modify the table entry of the basic routing path, which has less operation on the routing table and can reduce the impact of the switching of the backup routing path on the service traffic.

[0054] In the above embodiment, the PLR ​​node is in the basic routing path state before updating under normal working conditions, which is the initial state. In this state, the PLR ​​node processes and forwards data packets through the basic routing path, and pre-calculates and sends the backup routing path; the priority of the backup routing path in this state is lower than the priority of the basic routing path, and only when the hardware detection module senses a fault, the PLR ​​node will transfer from the initial state to the backup routing path state. The backup routing path state is an intermediate state, at which the priority of the backup routing path is modified to be higher than the priority of the basic routing path.

[0055] Step S20: When the link detection module detects that the flash fault evolves into a long-term stable fault, the local repair node floods the link status to all nodes in the satellite network, each of the nodes calculates a new basic routing path, and replaces the corresponding original basic routing path based on each of the new basic routing paths.

[0056] In this step, the long-term stable fault can be specifically detected based on the link fault detection module; the long-term stable fault can be specifically a second-level fault. It can be understood that the stable fault lasts longer than the flash fault, which will trigger the link fault detection timer to time out, and then trigger the basic route recalculation to generate a basic route that bypasses the fault. Exemplarily, replacing the corresponding original basic routing path based on each of the new basic routing paths includes: setting the priority of each of the new basic routing paths to the same priority as the corresponding original basic routing path; after each node calculates the new basic routing path, it sends down the basic routing entry with a priority lower than the backup routing path. At this time, the table entry priority of the new basic routing path is lower than the table entry priority of the backup routing path, then the data is still forwarded through the backup routing path, and the new basic routing path is not effective.

[0057] Step S30: the local repair node switches the backup routing path to a new basic routing path corresponding to the local repair node, so as to forward the data packet based on the new basic routing path.

[0058] This step further switches the backup routing path to the new basic routing path, so that the data packet is further forwarded through the new basic routing path. The local repair node switches the backup routing path to the new basic routing path corresponding to the local repair node, including: the local repair node sets the priority of the corresponding new basic routing path to be higher than the priority of the backup routing path; in this embodiment, the priority of the backup routing path is reduced to be lower than the priority of the new basic routing path, and the relevant traffic is switched to the converged new basic routing path; in this case, the PLR ​​is transferred from the backup path state to the updated new basic routing path state, and the updated new basic routing path state is the stable state of the basic routing convergence after the failure; at this time, the priority of the backup routing path is modified to be lower than the priority of the converged new basic routing path, and the PLR ​​forwards the data packet through the converged new basic routing path.

[0059] refer to Figure 4 When a fault is detected, the PLR ​​node first senses the fault in time through hardware detection, and immediately switches the backup path locally to ensure that the service traffic is not interrupted. At the same time, if the fault is a stable long-term fault, as the fault time reaches the scale that can be perceived by the link fault detection mechanism, the whole network topology is triggered to be updated synchronously and converge to the new on-board basic route. At this time, the backup routing path can be switched back to the new basic routing path state.

[0060] The method of the above embodiment uses segmented routing to guide the affected traffic to the backup routing path, thereby recovering from the fault; and the present application also takes into account that when a stable fault is sensed based on the link fault detection mechanism, if the fault perception time threshold is set too short, it will cause frequent switching of the primary and backup paths, thereby generating unnecessary overhead; if the fault perception time threshold is set too long, it will cause a long period of communication interruption in the face of a flash failure; therefore, the present application specifically defines millisecond-level faults as flash failures, and second-level faults as long-term stable faults. The satellite network backup path switching control method of the present application does not need to frequently switch the primary and backup paths for long-term stable faults, and data transmission can be performed with lower overhead, that is, the backup path switching method under the coordinated action of hardware detection and link fault detection of the present application compensates for the communication interruption caused by the flash failure.

[0061] In some embodiments of the present invention, before the step of detecting that a flash fault evolves into a long-term stable fault based on a link detection module, the method further includes: determining whether the effectiveness time of the backup routing path reaches a preset effectiveness time; when the preset effectiveness time is reached, determining whether the flash fault is repaired; when the flash fault is repaired, the local repair node switches the backup routing path to the original basic routing path.

[0062] In the above embodiment, in order to avoid the overhead caused by frequent switching between the primary path and the backup path under a flash failure, after the PLR ​​detects the flash failure based on the hardware detection module and switches from the basic routing path to the backup routing path, it further monitors the effective time of the backup routing path. For example, Figure 5 As shown, the satellite node may specifically include a backup path effectiveness timer module, at which the effectiveness time of the backup routing path can be judged based on the backup path effectiveness timer, that is, whether the effectiveness time of the backup routing path reaches the effectiveness preset time based on the backup path effectiveness timer; if the backup path effectiveness timer times out, it indicates that the effectiveness time of the backup routing path reaches the effectiveness preset time, and if the backup path effectiveness timer does not time out, it indicates that the effectiveness time of the backup routing path does not reach the effectiveness preset time.

[0063] like Figure 3As shown, when the backup path effective timer times out, it is further determined whether the fault has been repaired; when the backup path effective timer times out and the fault is restored, the backup routing path is switched to the original basic routing path, that is, the priority of the backup routing path is reduced to be lower than the priority of the original basic routing path, so as to switch to the original basic routing path; if the backup path effective timer times out and the fault is not restored, the data packet is still forwarded based on the backup routing path. When the fault is restored and the backup routing path is switched to the original basic routing path, if a new flash fault occurs suddenly, the original basic routing path is switched to the backup routing path again, and the backup path effective timer is reset to determine the effective time of the backup routing path.

[0064] In other embodiments, if the effectiveness time of the backup routing path does not reach the preset effectiveness time, it is determined whether the flash failure has evolved into a long-term stable failure; this embodiment senses whether the flash failure has evolved into a long-term stable failure based on the link fault detection mechanism during the timing period of the backup path effectiveness timer.

[0065] When the link fault detection module senses a long-term stable fault, the local repair node switches the backup routing path to the new basic routing path corresponding to the local repair node, specifically including: judging whether the release time of the backup routing path reaches the preset release time, and when the preset release time is reached, the local repair node switches the backup routing path to the new basic routing path corresponding to the local repair node. Figure 5 As shown, the satellite node may specifically include a backup path release timer module. In this embodiment, the release time of the backup routing path is judged based on the backup path release timer, that is, whether the release time of the backup routing path reaches the preset release time is judged based on the backup path release timer. If the backup path release timer times out, it means that the release time of the backup routing path reaches the preset release time. If the backup path release timer does not time out, it means that the release time of the backup routing path does not reach the preset release time. When the preset release time is reached, the backup routing path is switched to the new basic routing path.

[0066] like Figure 3 As shown in , if the link fault detection mechanism senses that the fault is a long-term stable fault, the fault information will be flooded to the entire network, and a new basic routing path with a priority equal to the original basic routing path will be issued after convergence. At the same time, a backup path release timer is set. After the backup path release timer times out, the priority of the backup routing path is reduced to be lower than the priority of the new basic routing path, so as to switch to the new basic routing path on the satellite. Among them, the schematic diagram of the routing path after convergence is shown in Figure 2 As shown, in Figure 2In the definition, the P space and Q space in TI-LFA are used; the P space refers to the set of all reachable nodes in the SPF tree established with the source end of the protection link as the root node, but not through the protection link; the Q space is the set of all reachable nodes in the reverse SPF tree established with the end of the protection link as the root node, and not through the protection link; the PQ node refers to the node located in both the extended P space and the Q space. When the intersection contains multiple nodes, the node closest to the source node is selected as the PQ node; if the P space and the Q space have no intersection, the adjacent nodes in the P space and the Q space are selected as the P point and the Q point, which are used as the destination of the SR backup path.

[0067] To more clearly describe the active / standby path switching in the PLR ​​control plane process, Figure 3 The state transition of PLR is shown; the following content starts with the state of PLR, analyzes the relationship between the basic routing path and the backup routing path of PLR in each state, the triggering conditions for switching between the backup routing path and the basic routing path, the role of the timer, etc.

[0068] 1) Basic routing path status before update

[0069] Under normal circumstances, PLR is in the basic routing path state before the update; this state is the initial state. In this state, PLR processes and forwards data packets through the basic routing path, and pre-calculates and sends the backup routing path. At this time, the priority of the backup routing path is lower than the priority of the basic routing path; only when the hardware detection senses a fault, PLR will transfer from the initial state to the backup routing path state.

[0070] 2) Backup routing path status

[0071] The backup routing path state is an intermediate state; at this time, the priority of the backup routing path is modified to be higher than the priority of the basic routing path. This state is more complex. The maintenance and transition of this state are affected by the backup path validity timer and the backup path release timer. The specific functions of the two timers are as follows:

[0072] After the hardware detection module senses a flash failure and switches to the backup routing path, in order to avoid the overhead caused by frequent switching between the backup routing path and the basic routing path, a backup path effectiveness timer is set at this time. Before the backup path effectiveness timer times out, the path always remains on the backup routing path.

[0073] When the link fault detection module detects that the fault is a long-term stable fault, the PLR ​​also provides backup routing path switching capability for long-term stable faults. After the PLR ​​finds the fault through the link fault detection module, in order to reduce the microloop caused by the delay of fault information flooding, the backup path release timer is set; the timer duration is recommended to be in seconds, in order to cover the maximum flooding of the entire network, basic routing calculation and downlink delay, so the timing duration of the timer depends on the size of the constellation, and the specific configuration needs to be made by the network management system.

[0074] If the link fault detection module senses a fault during the timing period specified by the backup path validation timer, the backup path validation timer should be canceled and a backup path release timer should be set.

[0075] The backup routing path status is transferred to the basic routing path status in the following two situations according to the type of fault:

[0076] Case 1: A flash failure. The duration of the failure cannot be sensed by the link fault detection module, that is, it will not trigger a change in the basic routing path of the entire network. In this case, the backup routing path will become invalid directly after the backup path effectiveness timer times out and the fault is restored, that is, it will switch back to the original basic routing path; specifically, the routing priority of the backup routing path is reduced to be lower than the priority of the original basic routing path; in this case, the PLR ​​is transferred from the backup routing path state to the original basic routing path state before the update.

[0077] Case 2: Stable fault. This fault lasts for a long time and triggers the timeout of the fault detection timer corresponding to the link fault detection module. At this time, the new basic routing path will be recalculated to generate a new basic routing path that bypasses the fault. At this time, the backup routing path needs to be released and switched to the new basic routing path. After the link fault detection module detects the fault, it will flood the link status to the entire network to synchronize the topology information. However, due to the existence of flooding delay, it may cause temporary inconsistency in the topology information of the nodes on the satellite, and eventually lead to routing micro-loops, affecting data transmission. To solve this problem, after the calculation of the new basic routing path is completed, it is delayed for a period of time before it takes effect. During this period, the backup routing path is still used to forward data. Since the backup routing path is based on the SR routing method, the data packet path can be explicitly specified, so the occurrence of loops can be avoided.

[0078] The specific implementation of the above situation 2 includes the following two stages:

[0079] In the first stage, after the new basic routing path is calculated, a new basic routing path entry with a lower priority than the backup routing path is issued, the backup path validity timer is canceled, and the backup path release timer is set; since the priority of the new basic routing table entry is lower than the priority of the backup routing path at this time, the data is still forwarded through the backup routing path, and the new basic routing path is not effective; during the preset timing period of the backup path release timer, the PLR ​​directs the traffic to the explicit loop-free backup routing path.

[0080] In the second stage, after the backup path release timer times out, the PLR ​​converges to the new basic routing path; at this time, the priority of the backup routing path is reduced to be lower than the priority of the new basic routing path, and the relevant traffic is switched to the converged new basic routing path. In this case, the PLR ​​is transferred from the backup routing path state to the updated new basic routing path state.

[0081] In addition, for the intermediate node of the SR backup routing path, after receiving the data packet, it determines that the data packet is an SR backup routing path data packet; the intermediate node only needs to forward the data packet along the path specified by the label. Specifically, the intermediate node finds the egress port and label operation code of the data packet according to the label method, and then pops the top-level adjacent label of the header label stack to forward the data packet.

[0082] For the bottom node of the SR backup routing path, after it receives a data packet, if the data packet is an SR backup routing path data packet and the label in the label stack is the bottom label, it means that this node is the bottom node. The bottom node pops up the SR node label at the bottom of the stack and converts the message into a basic routing path message. It continues to look up the table for forwarding of the basic routing path and finally forwards it according to the matching egress port.

[0083] Through the above embodiments, it can be found that the satellite network backup path switching control method of the present application reduces the communication interruption time of the satellite communication system after a fault occurs by designing the switching method of the basic routing path and the backup routing path, enhances the stability of the data transmission of the satellite communication system, and reduces the consumption of on-board computing resources through a reasonable main-backup path switching mechanism. Through the collaborative work of hardware detection and link fault detection mechanisms, the satellite communication system improves the perception of flash faults, reduces the jitter communication interruption caused by flash faults, and makes the data transmission during the flash fault more stable, that is, optimizes the stability of the satellite communication system after the fault; and, the present application avoids the overhead caused by the frequent switching of the backup routing path and the basic routing path with the help of the backup path activation timer, and reduces the local micro-loop at the fault location caused by the fault information flooding delay with the help of the backup path release timer, thereby optimizing the utilization of on-board resources and improving the efficiency of fault recovery.

[0084] The embodiments of the present invention also provide a computer-readable storage medium and a computer program product, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the method described in any of the above embodiments are implemented. The computer-readable storage medium can be a tangible storage medium, such as a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a floppy disk, a hard disk, a removable storage disk, a CD-ROM, or any other form of storage medium known in the technical field.

[0085] It should be understood by those skilled in the art that the exemplary components, systems and methods described in conjunction with the embodiments disclosed herein can be implemented in hardware, software or a combination of the two. Whether it is performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention. When implemented in hardware, it can be, for example, an electronic circuit, an application specific integrated circuit (ASIC), appropriate firmware, a plug-in, a function card, etc. When implemented in software, the elements of the present invention are programs or code segments used to perform the required tasks. The program or code segment can be stored in a machine-readable medium, or transmitted on a transmission medium or a communication link via a data signal carried in a carrier.

[0086] It should be clear that the present invention is not limited to the specific configuration and processing described above and shown in the figures. For the sake of simplicity, a detailed description of the known method is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present invention is not limited to the specific steps described and shown, and those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present invention.

[0087] In the present invention, features described and / or illustrated for one embodiment may be used in the same or similar manner in one or more other embodiments, and / or combined with features of other embodiments or replace features of other embodiments.

[0088] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the embodiments of the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A satellite network backup path switching control method, characterized in that: The method comprises: When a flash failure is detected by the hardware detection module, the local repair node switches the current original basic routing path to a backup routing path to forward data packets based on the backup routing path; When the link detection module detects that the flash fault evolves into a long-term stable fault, the local repair node floods the link status to all nodes in the satellite network, each of the nodes calculates a new basic routing path, and replaces the corresponding original basic routing path based on each of the new basic routing paths; The local repair node switches the backup routing path to a new basic routing path corresponding to the local repair node, so as to forward the data packet based on the new basic routing path.

2. The satellite network backup path switching control method according to claim 1, characterized in that: Before the step of detecting that the flash fault evolves into a long-term stable fault based on the link detection module, the method further includes: Determine whether the effective time of the backup routing path reaches the effective preset time; When the preset effective time is reached, determining whether the flash fault is repaired; When the flash failure is repaired, the local repair node switches the backup routing path to the original basic routing path.

3. The satellite network backup path switching control method according to claim 2, characterized in that: The method further comprises: When the effectiveness time of the backup routing path does not reach the preset effectiveness time, it is determined whether the flash failure evolves into a long-term stable failure.

4. The satellite network backup path switching control method according to claim 3, characterized in that: The local repair node switches the backup routing path to a new basic routing path corresponding to the local repair node, including: It is determined whether the release time of the backup routing path reaches the preset release time. When the preset release time is reached, the local repair node switches the backup routing path to a new basic routing path corresponding to the local repair node.

5. The satellite network backup path switching control method according to claim 1, characterized in that: The local repair node switches the current original basic routing path to the backup routing path, including: The local repair node sets the priority of the backup routing path to be higher than the priority of the original basic routing path.

6. The satellite network backup path switching control method according to claim 1, characterized in that: Replacing the corresponding original basic routing path based on each of the new basic routing paths includes: setting the priority of each of the new basic routing paths to be equal to the priority of the corresponding original basic routing path; and / or, The local repair node switches the backup routing path to a new basic routing path corresponding to the local repair node, including: The local repair node sets the priority of the corresponding new basic routing path to be higher than the priority of the backup routing path.

7. The satellite network backup path switching control method according to claim 4, characterized in that: Determining whether the effective time of the backup routing path reaches the effective preset time, including: determining whether the effective time of the backup routing path reaches the effective preset time based on the backup path effective timer; Determining whether the release time of the backup routing path reaches the preset release time includes: determining whether the release time of the backup routing path reaches the preset release time based on a backup path release timer.

8. A satellite network backup path switching control system, the system comprising a processor, a memory and a computer program stored in the memory, characterized in that: The processor is used to execute the computer program. When the computer program is executed, the system implements the steps of the method according to any one of claims 1 to 7.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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