Deterministic routing construction method, forwarding method and system for satellite network

Abstract

The application provides a deterministic routing construction method, a forwarding method and a system of a satellite network, and the deterministic routing construction method comprises the following steps: according to service data and topology information of the whole satellite network, a plurality of feasible paths corresponding to the service data from a source node to a destination node are found; according to transmission configuration information of the service data and the topology information of the whole satellite network, a feasible path meeting preset transmission requirements is screened out from the plurality of feasible paths as a current target feasible path; path costs of each target feasible path are determined respectively, and a feasible path with the minimum path cost is selected as a deterministic forwarding path of the service data. In a high dynamic satellite network with topology connectivity jump and link propagation delay gradual change, the application can realize the designation and deterministic delay forwarding of an end-to-end path meeting delay requirements of delay-sensitive service data, can effectively reduce a large amount of reconfiguration overhead, and has strong scalability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of satellite network communication, and in particular to a deterministic routing construction method, a forwarding method and a system for a satellite network. BACKGROUND

[0002] Traditional satellite networks have the characteristics of wide coverage and strong invulnerability, and are widely used to provide communication services for remote areas or disaster relief situations. In recent years, with the development of low-orbit satellite technology, such as the reduction of design cost, large-scale manufacturing, the reduction of launch cost, the improvement of satellite on-board performance, etc., the development and application of satellite networks have ushered in new opportunities. Satellite networks are used to provide large-scale Internet of Things communication services in industrial Internet of Things, agricultural automation, offshore drilling platforms, etc. scenarios, ultra-reliable and low-latency communication services for military control, and satellite edge computing services, etc.

[0003] Currently, many communication or Internet services have adopted low-orbit constellations such as Starlink and Iridium for transmission. However, the current low-orbit constellation only provides non-deterministic end-to-end service capability, lacks deterministic guarantees for bandwidth, latency, jitter, packet loss, etc., and is difficult to support the further popularization and development of low-orbit satellite networks. For example, when using a satellite network to control a drone beyond visual range, the satellite network is required to support low-latency and high-reliability control signaling transmission. Taking the communication from a drone to a ground station as an example, the latency is required to be less than 50 milliseconds, and the reliability is required to be less than 10 -3 -6 packet error rate. Remote industrial Internet interconnection scenarios based on satellite networks, such as remote implementation of cloud programmable logic controllers (PLC), interconnection of geographically dispersed factories, etc., also require deterministic requirements for latency, jitter and reliability. Remote real-time video backhaul and interaction based on satellite networks require greater bandwidth and lower latency, such as 360° 4K cloud VR video transmission, which requires a bandwidth of 20-40 Mbps and a latency of less than 50 ms. The above businesses with strong real-time and reliability requirements all require deterministic service capabilities of low-orbit satellite networks.

[0004] For the deterministic guarantee problem in satellite networks, Li Hongyan proposed a routing algorithm based on time-varying continuous graph model in the paper Time Deterministic Routing Algorithm and Protocol for Integrated Space-ground Networks Based on Time-varying Graph in Journal of Communications. Since time-varying continuous graph can represent the space-time attributes of multi-dimensional resources in satellite networks, the routing calculated based on it has time attributes and can guarantee the resource occupation at each time point. However, the calculation of resource occupation based on time-varying continuous graph needs to integrate time, which has extremely high computational complexity and poor scalability, so it cannot be practically applied to end-to-end deterministic routing selection in satellite networks. Moreover, this method selects network layer routing from the control plane perspective, but does not design the shaping and forwarding behavior of switches for traffic from the data plane perspective, so this method can only achieve coarse-grained deterministic service guarantee effect. Xu Chuan proposed in the paper Research on Satellite Time-sensitive Network Flow Scheduling in the Integration of Wired and Wireless in Journal of Electronics & Information Technology in 2022 that based on TDMA technology (Time division multiple access), the wireless time slots of inter-satellite links are allocated to realize non-waiting and non-packet loss inter-satellite deterministic scheduling. However, this technology is designed for the forwarding behavior of single-hop inter-satellite links in low-orbit satellite formation scenarios, and cannot realize end-to-end multi-hop global deterministic quality of service guarantee in satellite networks.

[0005] Current time deterministic network technology for ground networks supports bounded deterministic transmission mechanism for delay jitter sensitive traffic flows in networks of different scales. Through TSN (Transmission Sequence Number) at the data link layer and DetNet (Deterministic Network) at the network layer, the forwarding path and the queuing delay in each node are planned to ensure the timely, on-time and collaborative reachability of end-to-end services. However, this technology cannot meet the more diverse satellite network services in large-scale satellite networks, as well as the working needs of space links with dynamic, long propagation delay, high bit error rate and other characteristics. TSN two-layer deterministic delay guarantee technology is suitable for small-scale local area networks and periodic small packets, and is not suitable for deterministic satellite networks. In addition, the research work of DetNet is not completely mature, and the dynamic characteristics of satellite networks also make DetNet technology not suitable for satellite deterministic networks.

[0006] Specifically, the current stage of low-orbit satellite network provides end-to-end time deterministic service, still faces the following specific challenges: (1) the propagation delay and transmission path change caused by the high-speed movement of low-orbit satellite greatly increase the difficulty of providing delay deterministic guarantee; (2) the network fine-grained agile management is limited due to the traditional real-time path inquiry and flow table routing scheme of the SDN network (Software Defined Network, software defined network) based on the large space-time scale satellite network, so that the Internet business transmission faces the problems of large delay and limited scalability; and the frequent updating of routing strategy caused by the topology change greatly increases the signaling overhead. SUMMARY

[0007] In view of this, the embodiments of the present application provide a satellite network deterministic routing construction method, forwarding method and system to eliminate or improve one or more defects in the prior art.

[0008] One aspect of the present application provides a satellite network deterministic routing construction method, comprising:

[0009] Real-time collection of transmission configuration information of business data to be transmitted in a satellite network and topology information of the entire satellite network in a global view of the satellite network, continuous recording of change data of the global view of the satellite network; according to the business data and the topology information, finding a plurality of feasible paths corresponding to the business data respectively from a source node to a destination node; according to the transmission configuration information of the business data and the topology information of the entire satellite network, screening out a feasible path meeting a preset transmission requirement from the plurality of feasible paths as a current target feasible path; respectively determining the path cost of each target feasible path, and selecting the feasible path with the minimum path cost as the deterministic forwarding path of the business data.

[0010] In some embodiments of the present application, the transmission configuration information of the business data includes: long-term average rate of business data transmission, maximum burst of business data transmission, end-to-end delay requirement and maximum length of each priority data packet.

[0011] In some embodiments of the present application, the topology information of the satellite network includes:

[0012] The maximum bandwidth of the egress port of each satellite node; the maximum allocation bandwidth of each priority queue in the egress port of each satellite node; the token bucket credit accumulation rate and credit sending rate of each priority queue of the credit-based shaper; the maximum buffer size of each priority queue in the egress port of each satellite node; and the link propagation delay between each satellite node.

[0013] In some embodiments of the present application, the filtering of the feasible paths that meet the preset transmission requirements from the plurality of feasible paths according to the transmission configuration information of the service data and the topology information of the entire satellite network to obtain the current target feasible path comprises:

[0014] In the plurality of feasible paths, it is determined whether the total delay required for performing the service data forwarding according to each feasible path meets the end-to-end delay requirement of the service data from the source node to the destination node; the total delay required for performing the service data forwarding comprises the sum of the maximum delay of the priority queue of each satellite node and the sum of the propagation delay between the satellite nodes; if there is a feasible path that meets the end-to-end delay requirement of the service data forwarding, it is determined whether the bandwidth resource required for performing the service data forwarding according to each feasible path meets the maximum allocated bandwidth of the priority queue of each satellite node; the bandwidth resource is used to represent the sum of the occupied bandwidth of the priority queue of each satellite node through which the service data forwarding passes and the average rate of the service data forwarding; if there is a feasible path that meets the maximum allocated bandwidth of the priority queue of each satellite node, it is determined whether the buffer resource required for performing the service data forwarding according to each feasible path meets the maximum allocated buffer of the priority queue of each satellite node; the buffer resource is used to represent the sum of the occupied buffer size of the priority queue of each satellite node through which the service data forwarding passes and the maximum burst of the service data transmission; and the feasible path that meets the end-to-end delay requirement of the service data forwarding, the maximum allocated bandwidth of the priority queue of each satellite node and the maximum allocated buffer of the priority queue of each satellite node is filtered.

[0015] In some embodiments of the present application, the filtering of the feasible paths that meet the preset transmission requirements from the plurality of feasible paths according to the transmission configuration information of the service data and the topology information of the entire satellite network to obtain the current target feasible path further comprises: filtering the feasible paths that meet the preset transmission requirements of the service data from the plurality of feasible paths in turn according to the total propagation delay of each feasible path from small to large.

[0016] In some embodiments of the present invention, determining the path cost of each of the target feasible paths includes: calculating the difference in the occupied buffer size of the specified priority queue before and after the target feasible path is mapped to the specified priority queue in the satellite node; dividing the difference by the maximum allocated buffer size of the specified priority queue, and then dividing by the maximum burst of the service data transmission, to obtain the path cost of the specified priority queue; and calculating the sum of the path costs of the specified priority queues in each satellite node indicated in the target feasible path to obtain the path cost of the target feasible path.

[0017] A second aspect of the present invention provides a deterministic routing and forwarding method for satellite networks, comprising:

[0018] The deterministic routing and forwarding method of the satellite network described above is executed to obtain a deterministic forwarding path for the service data. The service data packet carrying the service data and the deterministic forwarding path are then sent to the source node of the service data. In the global view, the occupied bandwidth and occupied buffer size on the priority queues specified in each satellite node along the deterministic forwarding path are deducted. The service data is forwarded by each satellite node specified in the deterministic forwarding path according to the deterministic forwarding path. After the service data is forwarded from the source node to the destination node, the occupied bandwidth and buffer size on the priority queues specified in each satellite node along the deterministic forwarding path are released again in the global view.

[0019] A third aspect of the present invention provides a deterministic routing and forwarding method for satellite networks, comprising:

[0020] The system receives service data packets carrying service data and a deterministic forwarding path for the service data from the controller of the satellite network. The deterministic forwarding path is pre-obtained by the controller based on the aforementioned deterministic routing construction method for the satellite network. If the controller determines that it is the source satellite node corresponding to the service data based on the deterministic forwarding path, it applies a label to the received service data packet and pushes the deterministic forwarding path of the service data into the header of the service data packet in the form of a label stack. Based on the priority of the service data, the system adds the service data packet to a designated priority queue. The system then forwards the service data packet to the next satellite node specified by the deterministic forwarding path according to a credit shaping algorithm. This process continues until the service data packet is forwarded to the destination node, completing the forwarding of the service data packet.

[0021] Another aspect of the present application provides a deterministic routing system of a satellite network, comprising a processor and a memory, the memory having computer instructions stored therein, the processor being configured to execute the computer instructions stored in the memory, and the system implementing the steps of the deterministic routing construction method of a satellite network, the deterministic routing forwarding method of a satellite network of the second aspect, or the deterministic routing forwarding method of a satellite network of the third aspect when the computer instructions are executed by the processor.

[0022] Another aspect of the present application provides a computer readable storage medium having a computer program stored thereon, the program implementing the steps of the deterministic routing construction method of a satellite network, the deterministic routing forwarding method of a satellite network of the second aspect, or the deterministic routing forwarding method of a satellite network of the third aspect when the program is executed by a processor.

[0023] The deterministic routing construction method, transformation method and system of a satellite network of the present application can create an end-to-end deterministic path that meets the delay requirement for delay-sensitive service data in a high-dynamic satellite network with topology connectivity jump and link propagation delay gradual change, while taking into account the limited on-board resources of each satellite node and the occupation of the satellite node buffer, so as to effectively avoid the influence of uncertain factors such as service data packet overflow or packet loss. The present application is suitable for the case of high-speed periodic change of large-scale satellite networks, can effectively reduce a large amount of reconfiguration overhead, and has strong scalability.

[0024] Additional advantages, objects, and features of the application will be set forth in part by the description that follows, and will in part be apparent to those of ordinary skill in the art upon examination of the following or can be learned from practice of the application. The objects and other advantages of the application can be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

[0025] It will be understood by those skilled in the art that the objects and advantages of the present application can be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. BRIEF DESCRIPTION OF DRAWINGS

[0026] The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the principles of the application.

[0027] Figure 1 Flow chart for deterministic routing construction of a satellite network.

[0028] Figure 2 Arrival curve function of a priority queue minus service curve function of a priority queue.

[0029] Figure 3 Flow chart for selecting a deterministic forwarding path from a plurality of feasible paths. DETAILED DESCRIPTION

[0030] In order to make the objects, technical solutions, and advantages of the present application clearer, the present application will be described in further detail below with reference to the embodiments and drawings. Here, the illustrative embodiments of the present application and their descriptions are used to explain the present application but are not intended to limit the present application.

[0031] It should also be noted that, in order to avoid obscuring the present application with unnecessary details, only the structures and / or processing steps closely related to the solutions according to the present application are shown in the drawings, and other details not closely related to the present application are omitted.

[0032] It should be emphasized that the terms “comprises / comprising” when used in this specification are taken to specify the presence of stated features, elements, steps or components but do not preclude the presence or addition of one or more other features, elements, steps, components, or groups thereof.

[0033] It should also be noted that, unless specifically stated otherwise, the term “connected” in this specification can refer not only to direct connection, but also to indirect connection in the presence of an intermediate.

[0034] In the following, embodiments of the present application will be described with reference to the accompanying drawings. In the drawings, the same reference numerals represent the same or similar components, or the same or similar steps.

[0035] In view of the problem in the prior art that it is difficult to guarantee the delay determinacy of end-to-end data transmission due to the continuous change of propagation delay and transmission path of a satellite network with the high-speed periodic movement of low-orbit satellites, the present application proposes a deterministic routing construction method of a satellite network, which can be executed by a controller of the satellite network, as shown in Figure 1 The method comprises the following steps:

[0036] In step S110, transmission configuration information of service data to be transmitted in the satellite network and topology information of the entire satellite network in a global view of the satellite network are collected in real time, and change data of the global view of the satellite network is recorded continuously.

[0037] The transmission configuration information of the service data to be transmitted comprises a service data f i a long-term average rate of transmission, a maximum burst b i of the service data transmission, a delay requirement T i of an end-to-end, and a maximum length of service data packets of each priority The topology information of the whole satellite network includes: maximum bandwidth of the out port of each satellite node; maximum allocated bandwidth of each priority queue in the out port of each satellite node; token bucket credit accumulation rate idleSlope and credit sending rate sendSlope of each priority queue of the CBS (credit-based shaper) in each satellite node; maximum buffer size of each priority queue in the out port of each satellite node; and link propagation delay between each satellite node; wherein the CBS divides the traffic data transmission queue of each satellite node into A-class (strict delay bound) priority queue and B-class (loose delay bound) priority queue.

[0038] The change data of the global view of the satellite network is recorded continuously, including: based on the topology information of the whole satellite network in the global view of the satellite network collected in real time, obtaining the change data of the global view of the satellite network over time according to the satellite operation law shown in the ephemeris of the satellite network.

[0039] The global view of the satellite network is recorded in real time through the above step S110, so as to calculate the single-hop maximum delay of the A-class priority queue and the B-class priority queue of each satellite node according to the global view of the satellite network, and provide a calculation basis for deterministic routing of the satellite network, wherein the single-hop maximum delay includes logical delay, queuing delay and forwarding delay.

[0040] In step S120, according to the traffic data and the topology information, a plurality of feasible paths corresponding to each of the traffic data from the source node to the destination node are found.

[0041] In the above step S120, when the to-be-transmitted traffic data arrives at the controller of the satellite network, the shortest path algorithm is used in the controller of the satellite network to calculate the feasible paths between the source node and the destination node of the traffic data, that is, the transmission configuration information of the to-be-transmitted traffic data and the topology information of the satellite network are taken as the input information of the shortest path algorithm, and the shortest path algorithm finds the feasible paths between the source node and the destination node of the to-be-transmitted traffic data based on the priority queue in the topology information of the satellite network, and outputs a plurality of feasible paths of the to-be-transmitted traffic data.

[0042] In step S130, according to the transmission configuration information of the traffic data and the topology information of the whole satellite network, a feasible path meeting the preset transmission requirement is selected from the plurality of feasible paths as the current target feasible path.

[0043] In step S130, the feasible paths meeting the transmission requirements of the service data from the source node to the destination node are selected in order of the total propagation delay of each feasible path from small to large. The preset transmission requirements include the end-to-end delay requirement of service data forwarding, the maximum allocated bandwidth of the priority queue of each satellite node, and the maximum allocated buffer size of the priority queue of each satellite node. Step S130 includes the following steps: determining whether the total delay required for performing the service data forwarding of the service data meeting the end-to-end delay requirement of the service data from the source node to the destination node, in the plurality of feasible paths, wherein the total delay required for performing the service data forwarding of the service data includes the sum of the maximum delay of the priority queue of each satellite node and the sum of the propagation delay between the satellite nodes; if there is a feasible path meeting the end-to-end delay requirement of the service data forwarding, determining whether the bandwidth resource required for performing the service data forwarding of the service data meeting the maximum allocated bandwidth of the priority queue of each satellite node, in the feasible path meeting the end-to-end delay requirement of the service data forwarding, wherein the bandwidth resource is used to represent the sum of the occupied bandwidth of the priority queue of each satellite node through which the service data forwarding passes and the average rate of the service data forwarding; if there is a feasible path meeting the maximum allocated bandwidth of the priority queue of each satellite node, determining whether the buffer resource required for performing the service data forwarding of the service data meeting the maximum allocated buffer size of the priority queue of each satellite node, in the feasible path meeting the maximum allocated bandwidth of the priority queue of each satellite node, wherein the buffer resource is used to represent the sum of the occupied buffer size of the priority queue of each satellite node through which the service data forwarding passes and the maximum burst of the service data transmission. The feasible path meeting the end-to-end delay requirement of the service data forwarding, the maximum allocated bandwidth of the priority queue of each satellite node, and the maximum allocated buffer size of the priority queue of each satellite node is selected.

[0044] In step S140, the path cost of each target feasible path is determined, and the feasible path with the minimum path cost is selected as the deterministic forwarding path of the service data.

[0045] The calculation of the path cost of each target feasible path includes calculating the difference between the occupied buffer size of the specified priority queue before and after the target feasible path is mapped to the specified priority queue of the satellite node. The calculation of the path cost of each target feasible path includes calculating the difference between the occupied buffer size of the specified priority queue before and after the target feasible path is mapped to the specified priority queue of the satellite node. The occupied buffer size of the specified priority queue of the satellite node after the service data to be transmitted is mapped to the specified priority queue of the satellite node, indicates the maximum allocated buffer of the priority queue x in the satellite node n; b indicates the maximum burst of the service data to be transmitted. wherein indicates the maximum allocated buffer of the priority queue x in the satellite node n; b indicates the maximum burst of the service data to be transmitted. new indicates the maximum burst of the service data to be transmitted.

[0046] The calculation method is as follows: after the arrival of new service data to be transmitted, the arrival curve function of the priority queue is subtracted from the service curve function of the priority queue, and the maximum value of the difference function thus generated is the occupied buffer of the priority queue after the service data to be transmitted is successfully mapped to the priority queue in the satellite node. As shown in the following formula (3) : Figure 2 wherein r is the arrival rate of the arrival curve before the service data to be transmitted is mapped, b is the maximum burst of the arrival curve before the service data to be transmitted is mapped, r' is the arrival rate of the arrival curve after the service data to be transmitted is mapped, b' is the maximum burst of the arrival curve after the service data to be transmitted is mapped, R is the service rate of the priority queue, and T is the waiting service time of the priority queue.

[0047] In one embodiment, the satellite network deterministic routing creation system selects a deterministic forwarding path for the service data to be transmitted from a plurality of feasible paths, and the above steps S130-S140 are performed in the satellite network deterministic routing creation system. The shortest feasible paths from the source node to the destination node of the service data found are sequentially subjected to the process shown in the following formula (4) according to the propagation time delay from small to large in order: Figure 3

[0048] Step S131, the service data f new to be transmitted is sent to the satellite network deterministic routing creation system, and the shortest path algorithm is used to find a plurality of feasible paths from the source node to the destination node of the service data based on the priority queue in the system, to obtain a feasible path set P new containing a plurality of feasible paths, and the following judgment steps are sequentially performed on each feasible path in the feasible path set according to the propagation time delay from small to large indicated by the shortest path algorithm.

[0049] ​Step S132: Determine the maximum delay of the corresponding priority queue of each satellite node along the route when the service data to be transmitted is routed and forwarded according to the current feasible path. And the propagation delay d between each satellite node along the path n，m sum Is it less than the end-to-end delay requirement T for forwarding the service data to be transmitted? new If not, then abandon the current feasible path and repeat the judgment of the current step S132 for the next feasible path; where n represents the current satellite node, m represents the neighboring nodes of satellite node n, and x represents the priority queue in the satellite node.

[0050] Step S133: For the currently feasible path that meets the end-to-end delay requirements for forwarding the service data to be transmitted, as determined in step S132 above, determine the bandwidth already occupied in the priority queue of each satellite node along the route when the service data to be transmitted is routed and forwarded according to the currently feasible path. and the long-term average rate r of the service data to be transmitted new Is the sum less than the maximum allocated bandwidth of the priority queue of the corresponding satellite node? If not, abandon the current feasible path and repeat the judgment steps starting from step S132 for the next feasible path.

[0051] Step S134: For the currently feasible path that satisfies the maximum allocated bandwidth of the priority queues of each satellite node as determined in step S133 above, determine whether the buffer in the priority queue of each satellite node along the route is already occupied when the service data to be transmitted is routed and forwarded according to the currently feasible path. and the maximum burst of business data to be transmitted b new Is the sum less than the maximum allocation buffer of the priority queue of each corresponding satellite node? If not, abandon the current feasible path and repeat the judgment steps starting from step S132 for the next feasible path.

[0052] Step S141: For the currently feasible path that satisfies the maximum allocation buffer size of the priority queue of each satellite node as determined in step S134 above, calculate the path cost of the feasible path.

[0053] Step S142: Among all feasible paths, select the feasible path with the lowest path cost as the final determined service data f to be transmitted. new A deterministic forwarding path.

[0054] The application achieves the specification and determination of the end-to-end path in compliance with the delay requirement of the delay-sensitive service data and the deterministic forwarding of the end-to-end path in compliance with the delay requirement of the service data in the high-dynamic satellite network with the topology connectivity change and the gradual change of the link propagation delay, effectively avoids the influence of uncertain factors such as service data packet overflow or packet loss by considering the limited on-board resources of each satellite node and the occupation of the satellite node buffer in the determination of the end-to-end feasible path in compliance with the delay requirement of the service data, and has strong scalability by adopting the SR (Segment Routing, segment routing) mechanism to avoid a large amount of reconfiguration overhead by only configuring before the service data transmission.

[0055] The application further provides a deterministic routing forwarding method of a first satellite network, which can be executed by a controller of the satellite network, as shown in the method comprises the following steps S210-S240: Figure 3

[0056] Step S210, the deterministic routing creation method of the satellite network is executed to obtain the deterministic forwarding path of the service data.

[0057] Step S220, the service data packet carrying the service data and the deterministic forwarding path of the service data are issued to the source node of the service data, and the occupied bandwidth and the occupied buffer size on the priority queue specified in each satellite node on the deterministic forwarding path of the service data are deducted in the global view.

[0058] Since the satellite network is a constantly changing high-dynamic satellite network, the access satellite corresponding to each ground controller changes every period of time, so the source node of the service data issued by the controller is uniquely determined within a period of time. In the above step S220, the deterministic forwarding path of the service data is issued to the source node of the service data in the form of a segment routing SR label stack from the controller of the satellite network.

[0059] When a service data is transmitted in the satellite network according to the deterministic forwarding path, the controller receives a to-be-transmitted service data, and the occupied bandwidth and the occupied buffer size on the priority queue specified in each satellite node on the deterministic forwarding path of the service data are deducted in the global view in the above step S220, which can ensure the executability of the deterministic forwarding path of the to-be-transmitted service data currently constructed by the controller, avoid data stacking in the transmission process of the previous service data and the to-be-transmitted service data currently, and thus avoid the congestion of the satellite network.

[0060] ​The step S220 further comprises: for the source node of the service data, calculating the connection path of the satellite node under all topology snapshots within the transmission period of the service data from the controller to the source node, to ensure that the connection path and the transmission delay of the satellite node within the transmission period of the service data from the controller to the satellite node are determined. The topology snapshot is a static network topology divided every fixed period based on the snapshot idea for a dynamic network topology, so that the satellite network within the fixed period corresponding to each topology snapshot is assumed to be static, and the connection relationship, distance and path of the service data from the source node to the destination node between the satellite nodes are unchanged under each topology snapshot.

[0061] The step S230 comprises: forwarding the service data by the satellite nodes on the deterministic forwarding path to release the bandwidth and buffer occupied by the service data on the priority queue of the satellite nodes on the deterministic forwarding path in the global view.

[0062] Since the transmission process of the service data has been completed, the bandwidth and buffer resources occupied by the service data in the transmission process have been released, and therefore, the bandwidth and buffer occupied by the service data in the global view can be released by the process of releasing the bandwidth and buffer occupied by the service data on the priority queue of the satellite nodes on the deterministic forwarding path in the global view in the step S230, so as to improve the available resource of the satellite nodes in the satellite network and avoid the waste of the data transmission resources in the satellite network.

[0063] According to the priority of the service data, the service data packet of the service data is added to the specified priority queue;

[0064] The service data packet is forwarded to the next satellite node on the deterministic forwarding path according to the credit shaping algorithm, until the service data packet is forwarded to the destination node, and the forwarding of the service data packet is completed.

[0065] The application further provides a deterministic routing forwarding method of a second satellite network which can be executed by a satellite node in a satellite network, and the method comprises the following steps S310-S340:

[0066] The step S310 comprises: receiving a service data packet carrying service data and a deterministic forwarding path of the service data sent by a controller of a satellite network, wherein the deterministic forwarding path of the service data is obtained by the controller based on the above-mentioned deterministic routing construction method of the satellite network.

[0067] Step S320, if it is determined that the satellite node is the source satellite node of the service data according to the deterministic forwarding path, the label stack is pushed for the received service data packet, and the deterministic forwarding path of the service data is pushed into the header of the service data packet in the form of label stack.

[0068] Step S330, according to the priority of the service data, the service data packet of the service data is added into the designated priority queue.

[0069] Step S340, the service data packet is forwarded to the next satellite node specified by the deterministic forwarding path according to the credit shaping algorithm, until the service data packet is forwarded to the destination node, and the forwarding of the service data packet is completed.

[0070] The credit shaping algorithm is a CBS algorithm (Credit Based Shaper Transmission Selection Algorithm), which is a priority defined traffic shaping technology. The transmission time interval and the transmission frame size of the service data in the satellite node are specified. When the transmission of the service data in multiple priority queues in the same satellite node conflicts, the transmission interval and the transmission data volume of the service data in each priority queue are allocated fairly, so as to avoid the aggregation of the service data packets in the multiple priority queues at the outlet end of the satellite node, thereby avoiding the traffic burst caused by the aggregation.

[0071] In the above step S340, the service data packet is forwarded to the next satellite node specified by the deterministic forwarding path according to the credit shaping algorithm, which includes defining the credit value for the service data packet in each priority queue in each satellite node, and transmitting the service data packet in each satellite node according to the priority rules of each priority queue in the satellite node and the credit value of each priority queue. The credit value of each priority queue changes according to the transmission state of the service data packet in the priority queue. The current credit value available for transmission in each priority queue of each satellite node is credit, and the unit is bit (bit). The credit value growth rate of each priority queue of each satellite node is idleSlope, and the unit is bit per second (bit / s). The value of the credit value growth rate idleSlope is less than the transmission rate portTransmitRate of the output port of the corresponding satellite node. The credit value reduction rate of each priority queue of each satellite node is sendSlope, and the unit is bit per second (bit / s). sendSlope=idleSlope-portTransmitRate.

[0072] The transmission of the service data to be transmitted in each satellite node according to the priority rules of each priority queue in the satellite node and the credit value of each priority queue includes the following working conditions:

[0073] When there is control class data to be transmitted in the satellite node, the control class data is taken as the highest priority, and the output port of the satellite node first transmits the control class data to be transmitted, while keeping the credit values of other priority queues unchanged. When there are service data packets to be transmitted in multiple priority queues in the satellite node, the service data packets to be transmitted in each priority queue are transmitted in turn according to the priority rules between the priority queues. When there is a service data packet to be transmitted in a priority queue in the satellite node, the output port of the satellite node transmits the service data packet to be transmitted in the priority queue when the output port of the satellite node is in an idle state and the credit value of the priority queue is greater than or equal to 0.

[0074] In one embodiment, the satellite node performs transmission of the service data packet according to the credit shaping algorithm. When the data transmission starts, the credit value credit of each priority queue in the satellite node is 0, and the specific conditions include the following:

[0075] Condition 1: When there is a service data packet to be transmitted in a priority queue in the satellite node, if there is no service data packet being transmitted in the satellite node and no service data of a higher priority queue is waiting for transmission, the service data packet to be transmitted in the priority queue immediately starts to be transmitted, and the credit value credit of the priority queue continuously decreases at a rate of sendSlope. After the transmission of the service data packet is completed, the credit value of the priority queue is less than 0, and the credit value credit of the priority queue continuously increases at a rate of idleSlope until the credit value credit of the priority queue rises to 0, and the transmission of the service data packet to be transmitted in the priority queue can be continued.

[0076] Case 2: When there is one service data packet to be transmitted in one priority queue in the satellite node, if there is one conflicting service data packet being transmitted in the output port of the satellite node, the service data packet to be transmitted in the priority queue needs to wait for the transmission of the conflicting service data packet, and the credit value of the priority queue is continuously increased at the rate of idleSlope until the transmission of the conflicting service data packet is completed; at this time, the credit value of the priority queue is greater than 0, and the service data packet to be transmitted in the priority queue immediately enters the transmission state, and the credit value of the priority queue is continuously decreased at the rate of sendSlope until the transmission of the service data packet to be transmitted in the priority queue is completed; if the credit value of the priority queue is still greater than 0 at this time, and there is no service data packet to be transmitted in the priority queue, the credit value of the priority queue is set to 0.

[0077] Case 3: When there are multiple service data packets to be transmitted in one priority queue in the satellite node, if there is one conflicting service data packet being transmitted in the output port of the satellite node, the service data packets to be transmitted in the priority queue need to wait for the transmission of the conflicting service data packet, and the credit value of the priority queue is continuously increased at the rate of idleSlope until the transmission of the conflicting service data packet is completed; at this time, the credit value of the priority queue is greater than 0, and the service data packets to be transmitted in the priority queue immediately enter the transmission state, and the credit value of the priority queue is continuously decreased at the rate of sendSlope, and if one of the service data packets to be transmitted is transmitted, the credit value of the priority queue has been decreased to a negative number; at this time, the priority queue no longer meets the data transmission condition, and the credit value of the priority queue is continuously increased at the rate of idleSlope until the credit value of the priority queue returns to 0, and the remaining service data packets to be transmitted in the priority queue continue to perform data transmission, and the credit value of the priority queue is continuously decreased at the rate of sendSlope, and the credit value of the priority queue is decreased to a negative number again; then the transmission process of the service data packets to be transmitted in the priority queue is repeated until there is no service data packet to be transmitted in the priority queue, and the credit value of the priority queue is continuously increased at the rate of idleSlope to 0.

[0078] Case 4: When there are service data packets to be transmitted in multiple priority queues in the satellite node, the service data packets to be transmitted in the priority queues are transmitted according to the priority rules between the priority queues, and the transmission process of the service data packets to be transmitted in each priority queue is as shown in the above cases 1-3.

[0079] Case 5: When there is control class data to be transmitted in the satellite node, the control class data is given the highest priority, and the output port of the satellite node first transmits the control class data to be transmitted, while keeping the credit values of other priority queues unchanged; after the control class data to be transmitted is transmitted, the transmission of the service data packets to be transmitted in each priority queue in the satellite node is performed according to the above cases 1-4.

[0080] The application can effectively solve the problem that the service data packets to be transmitted of multiple different priority queues are aggregated at the output port of the satellite node, causing the buffer of the output port in each satellite node of the deterministic forwarding path to be overloaded, and then unable to give the deterministic guarantee of end-to-end delay for delay-sensitive data, by means of the credit-based traffic shaping mechanism in the end-to-end deterministic forwarding stage of the service data packets. Further, the application can effectively reduce the requirements of the data transmission process on the switch, and the modification cost is small, and has strong feasibility.

[0081] The application also provides a controller of a satellite network for executing all or part of the content of the deterministic routing creation method of the satellite network and / or the deterministic routing forwarding method of the first satellite network. The embodiments of the controller can be specifically used to execute the processing procedures of the embodiments of the deterministic routing creation method of the satellite network and / or the deterministic routing forwarding method of the first satellite network, and the functions thereof will not be repeated here, and can be referred to the detailed description of the embodiments of the deterministic routing creation method of the satellite network and / or the deterministic routing forwarding method of the first satellite network.

[0082] The controller performing part of the deterministic routing creation method of the satellite network and / or the deterministic routing forwarding method of the first satellite network can be executed in a server or completed in a client device. Specifically, the selection can be made according to the processing capacity of the client device and the limitation of the user's use scenario. The application does not make any limitation thereon. If all operations are completed in the client device, the client device can also include a processor for specific processing of the deterministic routing creation method of the satellite network and / or the deterministic routing forwarding method of the first satellite network.

[0083] The client device described above can have a communication module (i.e., a communication unit) that can be communicatively connected to a remote server to achieve data transmission with the server. The server can include a server of a task scheduling center, and in other implementation scenarios, can also include a server of an intermediate platform, such as a server of a third-party server platform that is communicatively linked to the server of the task scheduling center. The server can include a single computer device, or can include a server cluster composed of multiple servers, or a server structure of a distributed device.

[0084] The server and the client device can use any suitable network protocol to communicate, including a network protocol that has not been developed as of the filing date of the present application. The network protocol can include, for example, a TCP / IP protocol, a UDP / IP protocol, an HTTP protocol, an HTTPS protocol, and the like. Of course, the network protocol can also include, for example, a RPC protocol (Remote Procedure Call Protocol) used on top of the above-mentioned protocols, a REST protocol (Representational State Transfer), and the like.

[0085] The present application also provides a satellite node for performing all or part of the content of the above-mentioned second satellite network deterministic routing forwarding method. The embodiments of the satellite node can be used to perform the processing flow of the embodiments of the second satellite network deterministic routing forwarding method described above. The functions of the satellite node are not repeated here, and can be referred to the detailed description of the embodiments of the second satellite network deterministic routing forwarding method.

[0086] Corresponding to the above method, the present application also provides a satellite network deterministic routing system. The system includes a computer device, and the computer device includes a processor and a memory. The memory stores computer instructions, and the processor is configured to execute the computer instructions stored in the memory. When the computer instructions are executed by the processor, the system implements the steps of the above-mentioned satellite network deterministic routing construction method, the above-mentioned first satellite network deterministic routing forwarding method that can be executed by a controller of a satellite network, or the above-mentioned second satellite network deterministic routing forwarding method that can be executed by a satellite node in a satellite network.

[0087] The embodiments of the present application also provide a computer readable storage medium, which stores a computer program. The computer program is executed by a processor to implement the steps of the foregoing satellite network deterministic routing construction method, the first satellite network deterministic routing forwarding method which can be executed by a controller of the satellite network, or the second satellite network deterministic routing forwarding method which is executed by a satellite node in the satellite network. 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 memory disk, a CD-ROM, or any other form of storage medium known in the art.

[0088] Those of ordinary skill in the art will appreciate that the various illustrative components, systems and methods described in connection with the embodiments disclosed herein can be implemented as hardware, software, or a combination of both. The choice of hardware or software implementation is a matter of design choice and will depend on the particular application and constraints of the design. Those of skill in the art will be able to make such design choices without departing from the scope of the application. Aspects of the application can be implemented in hardware, for example, as an electronic circuit, as an application specific integrated circuit (ASIC), as a firmware, as an application specific integrated circuit (ASIC), as a plug-in, as a functional card, etc. Aspects of the application can also be implemented in software, for example, as a program or code segment. The program or code segment can be stored in a machine readable medium, or transmitted by a carrier wave in a transmission medium or communication link.

[0089] It is to be understood that the application is not limited to the particular configurations and processes described herein and shown in the drawings, which are provided by way of example only. Detailed descriptions of known methods are omitted so as not to obscure the description of the present application. In the above embodiments, several specific steps are described and illustrated in order to provide a thorough disclosure of the application. However, the method process of the application can be performed in a number of different specific sequences, and steps can be modified, combined, or omitted away without departing from the spirit of the application.

[0090] In the present application, features described and / or illustrated in relation to one embodiment can be used in the same or a similar way in one or more other embodiments, and / or combined with or instead of features on other embodiments.

[0091] The above description is merely illustrative of the application, and is not intended to limit the scope of the application. Various modifications and changes can be made by those of ordinary skill in the art without departing from the spirit and scope of the application. Any modification, equivalent replacement, improvement, and the like made within the spirit and principle of the application shall fall within the scope of the application.

Claims

1. A deterministic route construction method for a satellite network, characterized in that, The method comprises the following steps: collecting transmission configuration information of service data to be transmitted in a satellite network and topology information of the entire satellite network in a global view of the satellite network, and continuously recording change data of the global view of the satellite network; finding a plurality of feasible paths corresponding to the service data respectively from a source node to a destination node according to the service data and the topology information; selecting a feasible path meeting preset transmission requirements as a current target feasible path from the plurality of feasible paths according to the transmission configuration information of the service data and the topology information of the entire satellite network; determining path overheads of each of the target feasible paths respectively, and selecting a feasible path with the minimum path overhead as a deterministic forwarding path of the service data; the step of determining the path overheads of each of the target feasible paths respectively comprises the following steps: calculating a difference between occupied buffer sizes of a specified priority queue before and after the target feasible path is mapped to the specified priority queue; dividing the difference by a maximum allocated buffer size of the specified priority queue, and then dividing the result by a maximum burst of the service data transmission, to obtain a path overhead of the specified priority queue; and calculating a sum of path overheads of the specified priority queues in each satellite node indicated in the target feasible path, to obtain the path overhead of the target feasible path. the transmission configuration information of the service data comprises a long-term average rate of the service data transmission, a maximum burst of the service data transmission, an end-to-end delay requirement, and a maximum length of a service data packet of each priority.

2. The method of claim 1, wherein, the topology information of the satellite network comprises:

3. The method of claim 1, wherein, a maximum bandwidth of an outport of each satellite node; a maximum allocated bandwidth of each priority queue in the outport of each satellite node; a token bucket credit accumulation rate and a credit sending rate of a credit-based shaper (CBS) of each priority queue; a maximum buffer size of each priority queue in the outport of each satellite node; and a link propagation delay between each satellite node. the step of selecting the target feasible path meeting the preset transmission requirements from the plurality of feasible paths according to the transmission configuration information of the service data and the topology information of the entire satellite network comprises the following steps:

4. The method of claim 1, wherein, in the plurality of feasible paths, judging whether a total delay required for performing the service data forwarding according to each feasible path meets an end-to-end delay requirement of the service data from the source node to the destination node; the total delay required for performing the service data forwarding comprises a sum of maximum delays of priority queues of each satellite node and a sum of propagation delays between each satellite node; if there is a feasible path meeting the end-to-end delay requirement of the service data forwarding, judging whether a bandwidth resource required for performing the service data forwarding according to each feasible path meets a maximum allocated bandwidth of a priority queue of each satellite node; the bandwidth resource is used to represent a sum of an occupied bandwidth of a priority queue of each satellite node through which the service data forwarding passes and an average rate of the service data forwarding. ​ If there is a feasible path satisfying the maximum allocated bandwidth of the priority queue of each satellite node, it is judged whether the buffer resources required for performing the service data forwarding according to each feasible path satisfy the maximum allocated buffer of the priority queue of each satellite node; the buffer resources are used to represent the sum of the occupied buffer size and the maximum burst of the service data transmission of the priority queue of each satellite node in the service data forwarding path; The feasible queue satisfying the end-to-end delay requirement of the service data forwarding, the maximum allocated bandwidth of the priority queue of each satellite node, and the maximum allocated buffer of the priority queue of each satellite node is screened out.

5. The method of claim 1, wherein, The method further comprises the following steps of: screening out the feasible path satisfying the preset transmission requirement from the multiple feasible paths according to the transmission configuration information of the service data and the topology information of the entire satellite network, and taking the feasible path as the current target feasible path; and screening out the feasible path satisfying the preset transmission requirement of the service data from the multiple feasible paths in the order of the total propagation delay of each feasible path from small to large.

6. A deterministic routing and forwarding method for a satellite network, characterized in that, The method comprises the following steps: The method of any one of claims 1 to 5 is performed to obtain the deterministic forwarding path of the service data; The service data packet carrying the service data and the deterministic forwarding path of the service data are issued to the source node of the service data, and the occupied bandwidth and the occupied buffer size on the priority queue of each satellite node in the deterministic forwarding path are decremented in the global view; The service data is forwarded according to the deterministic forwarding path at each satellite node specified in the deterministic forwarding path, so that the occupied bandwidth and buffer size on the priority queue of each satellite node in the deterministic forwarding path are released again after the service data is forwarded from the source node to the destination node in the global view.

7. A deterministic routing and forwarding method for a satellite network, characterized in that, The method comprises the following steps: The service data packet carrying the service data and the deterministic forwarding path of the service data are issued to the source node of the service data, and the occupied bandwidth and the occupied buffer size on the priority queue of each satellite node in the deterministic forwarding path are decremented in the global view; If it is judged according to the deterministic forwarding path that the satellite node is the source satellite node corresponding to the service data, the received service data packet is labeled and stacked, and the deterministic forwarding path of the service data is stacked in the form of a label stack in the header of the service data packet; The service data packet of the service data is added to the specified priority queue according to the priority of the service data; The service data packet is forwarded to the next satellite node specified in the deterministic forwarding path according to the credit shaping algorithm; and the forwarding of the service data packet is completed until the service data packet is forwarded to the destination node. 8.A deterministic routing system for a satellite network, comprising a processor and a memory, wherein, The memory stores computer instructions, and the processor is configured to execute the computer instructions stored in the memory, and when the computer instructions are executed by the processor, the system implements the steps of the deterministic route construction method of the satellite network according to any one of claims 1 to 5, the deterministic route forwarding method of the satellite network according to claim 6, or the deterministic route forwarding method of the satellite network according to claim 7.

9. A computer readable storage medium having stored thereon a computer program, characterized in that, The program is executed by the processor to implement the steps of the deterministic route construction method of the satellite network according to any one of claims 1 to 5, the deterministic route forwarding method of the satellite network according to claim 6, or the deterministic route forwarding method of the satellite network according to claim 7.

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