Satellite network topology discovery method, path construction method and device

Abstract

The invention discloses a satellite network topology discovery method and a path construction method and device, and the method comprises the steps: dividing a satellite network into autonomous domains through distributing an extended SRv6 SID which comprises a network prefix, an orbital plane number, a node number, a service type and a resource margin for each satellite, and building an SID matrix and a satellite node adjacency matrix; the satellite nodes sense own resource states, periodically detect link states by adopting a BFD (Bidirectional Forwarding Detection) protocol, and synchronize values of elements in a matrix through an incremental updating mechanism to realize dynamic topology sensing; meanwhile, a routing path construction method based on an SID matrix and an adjacent matrix is provided, and satellite nodes are supported to carry out path calculation locally. The method supports heterogeneous service identification and resource state awareness, can effectively reduce signaling overhead, improves accuracy and routing efficiency of satellite network topology discovery, and improves cross-constellation computing power pooling and cooperative computing capability.

Description

Technical Field

[0001] This invention relates to the field of satellite networks, and in particular to a satellite network topology discovery method, path construction method, and apparatus. Background Technology

[0002] SRv6 (Segment Routing over IPv6) is a key technology for current network architecture innovation. It simplifies the complex protocol stack of traditional networks into a programmable IPv6 (Internet Protocol Version 6) data plane. By embedding the SRH (Segment Routing Header) extension header into IPv6 packets, SRv6 enables flexible arrangement of 128-bit segment identifiers (SIDs). The Locator identifies the node location, the Function defines the forwarding behavior, and the Args carries service parameters, forming a three-in-one intelligent routing system of "location-function-parameter".

[0003] However, in traditional SRv6, the traditional SID only supports terrestrial network topology identification and cannot effectively describe the dynamic altitude and position of satellite constellations, as well as onboard heterogeneous computing resources (such as FPGAs, CPUs, GPUs, etc.). At the same time, due to the lack of a standardized space computing power identification system, different satellite manufacturers adopt proprietary coding schemes, which severely restricts the development of cross-constellation computing power pooling and collaborative computing.

[0004] On the other hand, in traditional satellite network topology discovery protocols, network nodes primarily obtain network topology information within their own domain through Autonomous System (AS) level management mechanisms. Network nodes lack a global network topology structure and heavily rely on the controller for path construction.

[0005] A search of existing technologies revealed that Shandong Inspur Science Research Institute Co., Ltd., in its invention patent "SRv6-based Computing Power Routing System and Method" (application number CN202210458725.X), proposed that the computing power routing controller determines the computing power service SRv6 SID and forwarding action strategy of the computing power service gateway based on computing power service information and computing power routing information. Beijing Century Interconnect Broadband Data Center Co., Ltd., in its invention patent "Computing Power Information Notification Method, Computing Power Network Element Node, Device and Storage Medium" (application number CN202311014426.8), proposed using the extended Border Gateway Protocol (BGP) - Link State (LS) to encapsulate computing power status information, including the segment identifier (SID) of the computing power network element node. However, neither of these methods modifies the traditional SRv6 SID structure and therefore cannot identify heterogeneous computing power resources. Summary of the Invention

[0006] To address the aforementioned shortcomings of existing technologies, this invention provides a satellite network topology discovery method, path construction method, and apparatus, which solve the problem that satellite nodes cannot perceive global onboard heterogeneous computing resources and network topology in existing technologies.

[0007] The objective of this invention is achieved through the following technical solution:

[0008] A satellite network topology discovery method includes the following steps:

[0009] S1: The controller assigns an extended SRv6 SID to each satellite according to the format of the extended SRv6 SID, and each satellite generates an initial extended SRv6 SID; the extended SRv6 SID consists of six fields: network prefix, orbital plane number, node number, service type, resource margin, and must be set to zero.

[0010] S2: Divide the satellite network into different autonomous domains;

[0011] S3: Each satellite obtains the initial extended SRv6 SID of other satellites in its orbital layer and determines the number of satellite orbital planes and the number of satellite nodes in each orbital plane in its orbital layer;

[0012] S4: Establish a SID matrix for each satellite's orbital layer, and record the satellite's initial extended SRv6 SID in the SID matrix;

[0013] S5: Each satellite establishes a satellite node adjacency matrix for its orbital layer, which is used to represent the communication link connection relationship between satellites within its orbital layer;

[0014] S6: Each satellite senses its own resource status, updates the service type and resource balance fields in its extended SRv6 SID, and updates its extended SRv6 SID in the SID matrix; at the same time, each satellite periodically senses the link status with neighboring satellites within its orbital layer and updates the values ​​of the elements in the corresponding satellite node adjacency matrix.

[0015] S7: Each satellite synchronizes its SID matrix and satellite node adjacency matrix with neighboring satellites within its autonomous system until the values ​​of all elements in the SID matrix and satellite node adjacency matrix of all satellites within the autonomous system are the same.

[0016] S8: Within the same orbital layer, the boundary satellite nodes within each autonomous region first synchronize and update the SID matrix and satellite node adjacency matrix with the boundary satellite nodes of other autonomous regions across regions. Then, the boundary satellite nodes within each autonomous region synchronize and update the SID matrix and satellite node adjacency matrix of other autonomous regions with the satellite nodes within their own autonomous region, so that the values ​​of each element in the SID matrix and satellite node adjacency matrix of all satellites within the orbital layer are consistent.

[0017] S9: The boundary satellite nodes of each orbital layer synchronize the SID matrix and satellite node adjacency matrix within different orbital layers with the boundary satellite nodes of other orbital layers.

[0018] Furthermore, the total length of the extended SRv6 SID is 128 bits;

[0019] The service type field in step S6 is used to indicate whether the satellite node is suspending its service, or to indicate whether the satellite node provides a single service including forwarding, storage, and computing, or a heterogeneous service consisting of forwarding, storage, and computing.

[0020] Furthermore, in step S4, each satellite obtains the initial extended SRv6 SID of other satellites in its orbital layer in the following two ways:

[0021] Method 1: The controller sends a message to each satellite to announce the initial extended SRv6 SID of other satellites in its orbital layer;

[0022] Method 2: Each satellite discovers its neighbors within its orbital layer using internal gateway protocols and external gateway protocols, and exchanges initial extended SRv6 SIDs.

[0023] Furthermore, in step S5, the method for establishing the satellite node adjacency matrix for each satellite's orbital layer is as follows:

[0024] (1) Calculate the number of elements in the SID matrix N_ele=m*n based on the number of columns m and rows n of the SID matrix;

[0025] (2) Establish a satellite node adjacency matrix with N_ele columns and rows. Each element in the satellite node adjacency matrix stores a tuple, namely (link, ttl), where link is 0 to indicate a broken link, link is a positive real number to indicate link cost, and ttl indicates the predicted duration of the communication link connection. The initial value of each element tuple is set to (0,0).

[0026] Furthermore, in step S6, in order to reduce frequent network signaling interactions, the corresponding extended SRv6 SID is updated in the SID matrix of the satellite only when the predicted service duration is greater than a preset time threshold or the resource reserve change is greater than a preset capacity threshold.

[0027] Furthermore, in step S6, the method for determining the elements in the corresponding satellite node adjacency matrix is ​​as follows:

[0028] (1) First, number the elements in the SID matrix in ascending order of row number and then column number;

[0029] (2) Convert the value of the node number field of the extended SRv6 SID to decimal and determine the row i of the extended SRv6 SID in the SID matrix; convert the value of the track surface number field to decimal and determine the column j of the extended SRv6 SID in the SID matrix;

[0030] (3) Finally, calculate the number a of the extended SRv6 SID in the SID matrix element according to (j-1)*n+i, where n is the total number of rows in the SID matrix.

[0031] Furthermore, in step S6, updating the values ​​of the elements in the corresponding satellite node adjacency matrix specifically includes:

[0032] When two satellites establish a link, if the ttl of the corresponding element tuple (link, ttl) in the current satellite node's adjacency matrix is ​​equal to 0, it indicates that the link is in a failed state. In this case, the link value is modified to a positive real number, where the value of the positive real number represents the link cost, and ttl is set to the predicted duration of the communication link connection.

[0033] When two satellites establish a link, if the ttl of the corresponding element tuple (link, ttl) in the current satellite node adjacency matrix is ​​greater than 0, it indicates that the link is in a valid state. That is, the link connection state of the two satellites oscillates within the predicted duration of the communication link connection. If the link is broken and then re-established, the link value is only modified to a positive real number. The value of the positive real number represents the link cost.

[0034] Once the link between two satellites is established, if the link status is continuously monitored multiple times, the value of the corresponding element tuple (link, ttl) will not be changed.

[0035] Once the link between two satellites is established, if the link is broken in three consecutive link status detections, then the value of link in the corresponding element tuple (link, ttl) will be modified to 0 to mark the link as broken.

[0036] Once the link between the two satellites is established, when the TTL countdown reaches 0, the value of link in the corresponding tuple (link, ttl) is modified to 0 to mark the link as broken, and ttl is set to 0 to indicate that the link is in a failed state.

[0037] A method for constructing routing paths in a satellite network, which is based on a network topology constructed using a satellite network topology discovery method, includes the following steps:

[0038] Step 1: The source satellite node queries the SID matrix for target satellite nodes that meet the service type requirements and remaining resource requirements through its own node or the controller;

[0039] Step 2: The source satellite node determines the source satellite node and target satellite node numbers in the SID matrix through its own node or the controller;

[0040] Step 3: The source satellite node calculates the routing path based on the source and target satellite node numbers in the SID matrix and the satellite node adjacency matrix through its own node or the controller;

[0041] Step 4: The source satellite node obtains the extended SRv6 SID of the corresponding node based on the node number in the routing path calculation result through this node or the controller;

[0042] Step 5: The source satellite node fills the extended SRv6 SID of each node into the SRH extension header of its own node in sequence through its own node or the controller.

[0043] Furthermore, in step four, the method for obtaining the extended SRv6 SID of the corresponding node is as follows:

[0044] (1) Calculate the row number of the corresponding element in the SID matrix according to (y-1)mod n+1, where y is the node number in the path calculation result, n is the total number of rows in the SID matrix, and mod is the modulo operation;

[0045] The column number of the element in the corresponding SID matrix is ​​calculated based on floor((y-1) / n)+1, where floor() is the floor function.

[0046] (2) Obtain the extended SRv6 SID of the node based on the row and column number of the element in the SID matrix.

[0047] A satellite network topology discovery device is characterized by comprising a memory and one or more processors, wherein the memory stores executable code, and the one or more processors execute the executable code to implement a satellite network topology discovery method.

[0048] The beneficial effects of this invention are:

[0049] This invention improves the format of SRv6 SIDs, transforming it into extended SRv6 SIDs. While maintaining the total length of the SRv6 SID, this allows satellite nodes to grasp the global dynamic satellite network topology and perceive global heterogeneous onboard computing resources. Simultaneously, the method of this invention enables satellite nodes to construct routing paths locally without relying on a controller. This invention also effectively reduces signaling overhead and improves the accuracy of satellite network topology discovery and routing efficiency. Attached Figure Description

[0050] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0051] Figure 1 This is a schematic diagram illustrating the extended SRv6 SID format of the present invention;

[0052] Figure 2 This is a schematic diagram illustrating the Orbit Plane ID (orbital plane number) field format in the extended SRv6 SID format of this invention;

[0053] Figure 3 This is a schematic diagram illustrating the values ​​and meanings of the Orbital Layers field in the extended SRv6 SID format of this invention;

[0054] Figure 4 This is a schematic diagram illustrating the format of the ResourceAvailability field when a satellite node suspends service in the extended SRv6 SID format of this invention.

[0055] Figure 5 A schematic diagram illustrating the ResourceAvailability field format when providing a service type for satellite nodes in the extended SRv6 SID format of this invention;

[0056] Figure 6 This diagram illustrates the format of the ResourceAvailability field when satellite nodes provide two service types in the extended SRv6 SID format of this invention.

[0057] Figure 7 This diagram illustrates the format of the ResourceAvailability field when satellite nodes provide three service types in the extended SRv6 SID format of this invention.

[0058] Figure 8 This is a flowchart illustrating a satellite network topology discovery method according to an embodiment of the present invention.

[0059] Figure 9 A schematic diagram of satellite orbits, satellite node numbers, and the SID matrix;

[0060] Figure 10 This is a flowchart illustrating a satellite network routing path construction method according to another embodiment of the present invention.

[0061] Figure 11 This is a diagram illustrating the SRH extension header format and the SRH extension header abstract format. Detailed Implementation

[0062] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0063] Explanation of technical terms:

[0064] MBZ, Must Be Zero, must be set to zero;

[0065] BFD, Bidirectional Forwarding Detection;

[0066] FPGA stands for Field Programmable Gate Array.

[0067] CPU, Central Processing Unit;

[0068] GPU, Graphics Processing Unit;

[0069] NPU, Neural Processing Unit;

[0070] PLD stands for Programmable Logic Device.

[0071] EGP, Exterior Gateway Protocol;

[0072] IGP, Interior Gateway Protocol;

[0073] TB, Terabyte, terabyte;

[0074] MB, Megabyte;

[0075] GB stands for Gigabyte.

[0076] MHz, Megahertz;

[0077] GHz, Gigahertz;

[0078] MFLOPS, Million Floating-Point Operations Per Second;

[0079] GFLOPS, Giga Floating-point Operations Per Second;

[0080] TFLOPS, Tera Floating-Point Operations Per Second;

[0081] PFLOPS, Peta Floating-Point Operations Per Second;

[0082] MOPS stands for Million Operations Per Second.

[0083] GOPS stands for Giga Operations Per Second.

[0084] TOPS, Tera Operations Per Second.

[0085] POPS, Peta Operations Per Second, is one quadrillion operations per second.

[0086] SRH, Segment Routing Header;

[0087] TTL, Time to Live, refers to the lifespan of a computer.

[0088] It should be noted that, unless otherwise specified, the features in the following embodiments and implementation methods can be combined with each other.

[0089] Figure 1 This is a diagram of the extended SRv6 SID format. The traditional SRv6 SID format includes four fields: Locator, Function, Arguments, and MBZ (must be zeroed). The total length of these four fields is 128 bits.

[0090] The extended SRv6 SID divides the Locator field into three parts: Network Prefix, OrbitPlane ID, and Node ID. It defines the Service Type in the Function field and the Resource Availability in the Arguments field. The MBZ (must be zeroed) field is used to pad the least significant bits with zeros when the sum of the bits in the other three fields is less than 128 bits, ensuring the total length of the extended SRv6 SID is 128 bits, consistent with the traditional SRv6 SID length.

[0091] like Figure 1 As shown, in this embodiment, the Network Prefix field in the extended SRv6 SID format is 32 bits long, the Orbit Plane ID field is 12 bits long, the Node ID field is 8 bits long, the Service Type field is 8 bits long, and the Resource Availability field is 60 bits long. The length of each field in the above extended SRv6 SID format is only one example in this embodiment; the length of each field can be adjusted according to requirements.

[0092] Figure 2 This is a schematic diagram of the Orbit Plane ID field in the extended SRv6 SID format. The Orbit Plane ID field is divided into Orbital Layers and Orbit Plane No. fields. The Orbital Layers field is 4 bits long and is used to indicate the orbital altitude of the satellite. The Orbit Plane No. field is 8 bits long and is used to indicate the orbital number within the same orbital layer.

[0093] Figure 3 This diagram illustrates the values ​​and meanings of the Orbital Layers field in the extended SRv6 SID format of this invention. (See diagram for example.) Figure 3 As shown, in the Orbital Layers field, 0000 indicates the lower orbital, 0001 indicates the middle orbital, and 0010 indicates the upper orbital.

[0094] The Service Type field is used to represent the forwarding, storage, and computing services provided by the satellite node. For example, when a satellite node provides a single service type, the Service Type field uses 0x00 to indicate suspended service, 0x01 to indicate forwarding service, 0x02 to indicate storage service, 0x03 to indicate CPU computing service, 0x04 to indicate GPU computing service, 0x05 to indicate NPU computing service, and 0x06 to indicate FPGA computing service. When a satellite node provides more than two service types, the Service Type field uses 0x07 to indicate CPU and GPU heterogeneous computing service, 0x08 to indicate CPU and FPGA heterogeneous computing service, 0x09 to indicate CPU and NPU heterogeneous computing service, 0x0A to indicate storage, CPU and GPU heterogeneous computing service, 0x0B to indicate storage, CPU and FPGA heterogeneous computing service, and 0x0C to indicate storage, CPU and NPU heterogeneous computing service.

[0095] Figure 4This is a schematic diagram illustrating the format of the Resource Availability field when a satellite node suspends service in the extended SRv6 SID format. When the Service Type field indicates that the satellite node is suspending service (i.e., the value of the Service Type field is 0x00), the Resource Availability field is divided into an Error Code field and an MBZ (must be zeroed) field. The Error Code field is 8 bits long and indicates the reason for the satellite node's service suspension, such as 0x00 indicating insufficient resources, 0x01 indicating CPU hardware failure, etc. The MBZ (must be zeroed) field is padded with 0s to fill in the lowest few bits, making the total length of the Resource Availability field 60 bits.

[0096] When the Service Type field indicates that a satellite node provides one or more service types, the Resource Availability field is formatted as [Service Type 1 | Unit 1 | Resource Availability 1 | Service Type 2 | Unit 2 | Resource Availability 2 | ... | MBZ (must be zeroed)]. The ellipsis indicates that if there are more service types, they are added in the format [Service Type n | Unit n | Resource Availability n] .

[0097] Figure 5This is a schematic diagram of the ResourceAvailability field format when a satellite node provides a single service type in the extended SRv6 SID format. When the Service Type field indicates that the satellite node provides a single service type, i.e., when the value of the Service Type field is 0x01, 0x02, 0x03, 0x04, 0x05, or 0x06, the ResourceAvailability field is divided into Service Type 1, Unit 1, ResourceAvailability 1, and MBZ (must be zeroed) fields. The Service Type 1 field is 4 bits long, the Unit 1 field is 4 bits long, and the ResourceAvailability 1 field is 12 bits long. The MBZ (must be zeroed) field is used to pad the lowest few bits with 0 when the sum of the number of bits in the Unit 1 and Resource Availability 1 fields is less than 60 bits, so that the total length of the Resource Availability field is 60 bits.

[0098] The Service Type 1 field is used to represent the services provided by the satellite node, such as forwarding, storage, and computing. For example, 0x1 represents forwarding service, 0x2 represents storage service, 0x3 represents CPU computing service, 0x4 represents GPU computing service, 0x5 represents NPU computing service, and 0x6 represents FPGA computing service. The difference between the Service Type 1 field and the ServiceType field is that the ServiceType field is 8 bits long and can be used to represent multiple heterogeneous service types, while the Service Type 1 field is 4 bits long and is used only to represent a single service type.

[0099] The Unit 1 field is used to represent the unit of different resources. For example, when Service Type 1 indicates 0x1 forwarding service or 0x2 storage service, the Unit 1 field uses 0x0 to represent MB, 0x1 to represent GB, and 0x2 to represent TB. When Service Type 1 indicates 0x3 CPU computing service, the Unit 1 field uses 0x0 to represent MHz and 0x1 to represent GHz. When Service Type 1 indicates 0x4 GPU computing service or 0x6 FPGA computing service, the Unit 1 field uses 0x0 to represent MFLOPS, 0x1 to represent GFLOPS, 0x2 to represent TFLOPS, and 0x3 to represent PFLOPS. When Service Type 1 indicates 0x5 NPU computing service, the Unit 1 field uses 0x0 to represent MOPS, 0x1 to represent GOPS, 0x2 to represent TOPS, and 0x3 to represent POPS.

[0100] Figure 6 This is a schematic diagram of the ResourceAvailability field format when a satellite node provides two service types in the extended SRv6 SID format. When the Service Type field indicates that the satellite node provides two service types, i.e., when the value of the Service Type field is 0x07, 0x08, or 0x09, the ResourceAvailability field is divided into Service Type 1, Unit 1, ResourceAvailability 1, Service Type 2, Unit 2, ResourceAvailability 2, and MBZ (must be zeroed) fields. The Service Type 1 and Service Type 2 fields are both 4 bits long, the Unit 1 and Unit 2 fields are both 4 bits long, and the ResourceAvailability 1 and ResourceAvailability 2 fields are both 12 bits long. The MBZ (must be zeroed) field is used to pad the lowest few bits with 0 when the sum of the bits of the aforementioned fields is less than 60 bits, so that the total length of the Resource Availability field is 60 bits.

[0101] When the Service Type field indicates that a satellite node provides two service types, the Service Type 1 and Service Type 2 fields indicate the first and second service types respectively, the Unit 1 and Unit 2 fields indicate the units for the first and second service types respectively, and the Resource Availability 1 and Resource Availability 2 fields indicate the resource availability for the first and second service types respectively. The values ​​and meanings of the Service Type 1 and Service Type 2 fields are as follows: Figure 5 When a satellite node provides a specific service type, the value and meaning of the Service Type 1 field are the same. The values ​​and meanings of the Unit 1 and Unit 2 fields are also the same. Figure 5 When a satellite node provides a service type, the value and meaning of the Unit 1 field are the same. For example, when the Service Type field is 0x07 to indicate CPU and GPU heterogeneous computing services, the Service Type 1 value is 0x3 to indicate CPU computing services, and the Service Type 2 value is 0x4 to indicate GPU computing services.

[0102] Figure 7This is a schematic diagram of the ResourceAvailability field format when a satellite node provides three service types in the extended SRv6 SID format. When the Service Type field indicates that the satellite node provides three service types, i.e., when the value of the Service Type field is 0x0A, 0x0B, or 0x0C, the ResourceAvailability field is divided into Service Type 1, Unit 1, Resource Availability 1, Service Type 2, Unit 2, Resource Availability 2, Service Type 3, Unit 3, and Resource Availability 3. The Service Type 1, Service Type 2, and Service Type 3 fields are all 4 bits long, the Unit 1, Unit 2, and Unit 3 fields are all 4 bits long, and the Resource Availability 1, Resource Availability 2, and Resource Availability 3 fields are all 12 bits long.

[0103] When the Service Type field indicates that the satellite node provides three service types, the Service Type 1, Service Type 2, and Service Type 3 fields indicate the first, second, and third service types, respectively; the Unit 1, Unit 2, and Unit 3 fields indicate the units of the first, second, and third service types, respectively; and the ResourceAvailability 1, ResourceAvailability 2, and ResourceAvailability 3 fields indicate the resource availability of the first, second, and third service types, respectively. The values ​​and meanings of the Service Type 1, Service Type 2, and Service Type 3 fields are as follows: Figure 5 When a satellite node provides a specific service type, the value and meaning of the Service Type 1 field are the same. The values ​​and meanings of the Unit 1, Unit 2, and Unit 3 fields are also the same. Figure 5 When a satellite node provides a service type, the value and meaning of the Unit 1 field are the same. For example, when the Service Type field is 0x0A, indicating storage, CPU, and GPU heterogeneous computing services, the Service Type 1 value is 0x2, indicating storage services; the Service Type 2 value is 0x3, indicating CPU computing services; and the Service Type 3 value is 0x4, indicating GPU computing services.

[0104] Figure 8 This is a flowchart illustrating a satellite network topology discovery method according to an embodiment of the present invention. The process needs to be restarted whenever the number of satellite nodes in the satellite orbit layer changes. Figure 8 This involves processes such as phased release or orbit-changing injection of satellites, where multiple satellites can be deployed to the same orbit in batches. In this case, the basic topology of the satellite network changes, requiring a complete re-run. Figure 8 The process involves discovering satellite network topology.

[0105] like Figure 8 As shown, a satellite network topology discovery method in an embodiment of the present invention includes the following steps:

[0106] S101. The controller assigns an extended SRv6 SID to each satellite according to the format of the extended SRv6 SID. Each satellite generates an initial extended SRv6 SID. The extended SRv6 SID consists of six fields: network prefix, orbital plane number, node number, service type, resource margin, and fields that must be set to zero.

[0107] The controller pre-assigns Network Prefix, Orbit Plane ID (including Orbital Layers and Orbit Plane No.), Node ID, and Service Type fields to each satellite. Each satellite has a unique number consisting of Orbit Plane No. and Node ID.

[0108] For example, for satellite node 5 operating in low Earth orbit (LEO) with orbital plane number 4, assign a Network Prefix field of 2001:db8:: / 32, an Orbital Layers field of 0000 (indicating LEO), an Orbit PlaneNo. field of 0x04, and a Node ID field of 0x05. This satellite node provides heterogeneous computing services using both CPU and GPU; therefore, the Service Type field is configured to 0x07.

[0109] Each satellite generates an initial extended SRv6 SID based on the fields assigned by the controller. The ResourceAvailability field is filled with 0.

[0110] For example, the initial extension SRv6 SID of satellite node 5, which operates in low Earth orbit with orbital plane number 4 in S101, is 2001:db8:4:507::.

[0111] S102. Divide the satellite network into different autonomous domains.

[0112] For example, satellite networks within the same orbital layer and orbital plane number can be grouped into an autonomous system (AS) based on the Orbital Layers and OrbitPlane No. fields of the initial extended SRv6 SID. The EGP protocol runs between ASs, while the IGP protocol runs within ASs.

[0113] S103. Each satellite obtains the initial extended SRv6 SID of other satellites in its orbital layer and determines the number of satellite orbital planes and the number of satellite nodes in each orbital plane in its orbital layer.

[0114] Each satellite obtains its initial extended SRv6 SID from other satellites in its orbital layer using the following two methods:

[0115] Method 1: The controller (such as a ground control center, high-orbit satellite, etc.) sends a message to each satellite to announce the initial extended SRv6 SID of other satellites in its orbital layer;

[0116] Method 2: Each satellite, within its orbital layer, performs neighbor discovery using protocols such as IGP and EGP, and exchanges initial extended SRv6 SIDs.

[0117] Each satellite determines the number of satellite orbital planes and the number of satellite nodes in each orbital plane based on the initial extended SRv6 SID of all satellites in its orbital layer.

[0118] Each satellite examines the Orbital Layers field in the initial extended SRv6 SID of all satellites and selects the initial extended SRv6 SID of other satellites in the same orbital layer. Based on the Orbit Plane No. and Node ID fields in the initial extended SRv6 SIDs of all satellites in the same orbital layer, it counts to determine the number of satellite orbital planes m and the number of satellite nodes n(i) within each orbital plane (i=1,2,…,m).

[0119] S104. Establish a SID matrix for each satellite's orbital layer and record the satellite's initial extended SRv6 SID in the SID matrix.

[0120] Let m represent the number of satellite orbital planes in the orbital layer to which the satellite belongs, and n(i) represent the number of satellite nodes in orbital plane i (i=1,2,…,m) in the orbital layer to which the satellite belongs. Then, for each satellite, m is used as the number of columns in the SID matrix, and the maximum value n of n(i), i.e., n=max n(i), (i=1,2,…,m), is used as the number of rows in the SID matrix. A SID matrix is ​​built locally, where all elements in the SID matrix are initially 0.

[0121] At the same time, each satellite sorts the OrbitPlane No. field of the initial extended SRv6 SID of all satellites in its orbital layer in ascending order to the corresponding column in the SID matrix, sorts the Node ID field in ascending order to the corresponding row in the SID matrix, and records the initial extended SRv6 SID in the corresponding SID matrix element.

[0122] For example, suppose the satellite orbital planes in the orbital layer contain 6 satellites, and the six Orbit Plane No. fields are sorted in ascending order as 0x01, 0x02, 0x03, 0x04, 0x05, and 0x06. Simultaneously, orbital planes 1-5 each contain 5 satellites, and the five Node ID fields are sorted in ascending order as 0x01, 0x02, 0x03, 0x04, and 0x05. The sixth orbital plane contains 4 satellites, and the four Node ID fields are sorted in ascending order as 0x01, 0x02, 0x03, and 0x04. The SID matrix is ​​constructed as follows: Figure 9 As shown.

[0123] Figure 9 This is a schematic diagram of satellite orbits, satellite node numbers, and the SID matrix. Figure 9In the SID matrix, each element records the initial extended SRv6 SID value of the corresponding satellite. For example... Figure 9 In the SID matrix, SID5,4 represents the element value in the 5th row and 4th column. Here, 4 indicates the Orbit Plane No. (orbit plane number) field, which is the 4th position in ascending order within the satellite's orbital layer (0x04). 5 indicates the Node ID (orbit number) field, which is the 5th position in ascending order within the satellite's orbital layer (0x05). Based on the initial extended SRv6 SID generated in S101, the initial extended SRv6 SID of satellite node 5, operating in low Earth orbit with orbital plane number 4, is 2001:db8:4:507::. Therefore, the value of SID5,4 is 2001:db8:4:507::. Figure 9 The element value of 0 in the 5th row and 6th column of the SID matrix indicates that there is no satellite in the 6th position of the OrbitPlane No. (orbit plane number) that is sorted in ascending order and has the 5th position of the Node ID (node ​​number).

[0124] S105. Each satellite establishes a satellite node adjacency matrix for its orbital layer, which is used to represent the communication link connection relationship between satellites within its orbital layer.

[0125] Given the number of columns *m* and rows *n* of the SID matrix, calculate the number of elements in the SID matrix: N_ele = m * n. Construct a satellite node adjacency matrix with N_ele columns and rows. Each element in this adjacency matrix stores a tuple, (link, ttl), where link = 0 indicates a broken link, a positive real number represents the link cost, and ttl represents the predicted duration of the communication link connection. The initial value of each element tuple is set to (0, 0).

[0126] S106. Each satellite senses its own resource status, updates the contents of the Service Type and Resource Availability fields in its extended SRv6 SID, and updates its extended SRv6 SID in the SID matrix. At the same time, each satellite periodically senses the link status with neighboring satellites within its orbital layer and updates the values ​​of the elements in the corresponding satellite node adjacency matrix.

[0127] When each satellite senses its own resource status, if a satellite node suspends service, it sets the value of the Service Type field in the extended SRv6 SID to 0x00 and indicates the reason for the suspension in the Error Code field of the Resource Availability field. When the satellite node resumes service, it sets the value of the Service Type field in the extended SRv6 SID to its initial value. Furthermore, when the satellite node provides normal service, it determines the appropriate service status based on the value of the Service Type field in the extended SRv6 SID. Figure 5 , Figure 6 , Figure 7 The Resource Availability field format is shown, and the value in the corresponding Resource Availability field format in the extended SRv6 SID is modified according to the resource status awareness results.

[0128] In addition, when each satellite performs link status awareness within its orbital layer, it periodically conducts link status awareness with neighboring satellites via the BFD protocol according to the configured BFD detection time. To reduce frequent network signaling interactions, the corresponding extended SRv6 SID in the satellite's SID matrix is ​​updated only when the predicted service duration exceeds a preset time threshold (e.g., a mission lasting 10 minutes) or when the resource reserve changes more than a preset capacity threshold.

[0129] Taking two adjacent satellites in the same orbital layer (assuming the SIDs of the two satellites are extended SRv6 SID 1 and extended SRv6 SID 2, respectively) as an example, the method for determining the elements in the corresponding satellite node adjacency matrix is ​​as follows:

[0130] (1) First, number the elements in the SID matrix in ascending order of row number and then column number.

[0131] like Figure 9 As shown, the elements in the established SID matrix are numbered from ele1 to ele30 in ascending order of row number and column number.

[0132] (2) Convert the value of the Node ID field of the extended SRv6 SID (i.e., SRv6 SID 1) to decimal to determine the row i of the extended SRv6 SID (i.e., SRv6 SID 1) in the SID matrix; convert the value of the Orbit Plane No. field to decimal to determine the column j of the extended SRv6 SID (i.e., SRv6 SID 1) in the SID matrix.

[0133] (3) Calculate the number a of the extended SRv6 SID 1 in the SID matrix according to (j-1)*n+i, where n is the total number of rows in the SID matrix.

[0134] Similarly, to extend SRv6 SID 2, the number b in the SID matrix element is calculated using the same steps.

[0135] Updating the values ​​of the elements in the adjacency matrix of the corresponding satellite nodes specifically includes:

[0136] When two satellites establish a link, if the ttl of the corresponding element tuple (link, ttl) in the current satellite node's adjacency matrix is ​​equal to 0, it indicates that the link is in a failed state. In this case, the link value is modified to a positive real number, where the value of the positive real number represents the link cost, and ttl is set to the predicted duration of the communication link connection.

[0137] When two satellites establish a link, if the ttl of the corresponding element tuple (link, ttl) in the current satellite node adjacency matrix is ​​greater than 0, it indicates that the link is in a valid state. That is, the link connection state of the two satellites oscillates within the predicted duration of the communication link connection. If the link is broken and then re-established, the link value is only modified to a positive real number. The value of the positive real number represents the link cost.

[0138] Once the link between two satellites is established, if the link status is continuously monitored multiple times, the value of the corresponding element tuple (link, ttl) will not be changed.

[0139] Once the link between two satellites is established, if the link is broken in three consecutive link status detections, then the value of link in the corresponding element tuple (link, ttl) will be modified to 0 to mark the link as broken.

[0140] Once the link between the two satellites is established, when the TTL countdown reaches 0, the value of link in the corresponding tuple (link, ttl) is modified to 0 to mark the link as broken, and ttl is set to 0 to indicate that the link is in a failed state.

[0141] To prevent frequent changes in the adjacency matrix values ​​of satellite nodes due to frequent inter-satellite link disconnections, each satellite is configured with a dynamic BFD detection time based on the Orbital Layers field in its extended SRv6 SID. For example, an Orbital Layers field of 0000 indicates a low-Earth orbit (LEO) satellite, with a BFD detection time configured to 100 milliseconds; an Orbital Layers field of 0001 indicates a medium-Earth orbit (MEO) satellite, with a BFD detection time configured to 250 milliseconds; and an Orbital Layers field of 0010 indicates a high-Earth orbit (HEO) satellite, with a BFD detection time configured to 1000 milliseconds. Furthermore, for cases of consecutive link changes triggered within a certain period, the BFD detection time is extended by a factor of two and restored after the link situation stabilizes.

[0142] S107. Each satellite synchronizes its SID matrix and satellite node adjacency matrix with neighboring satellites within its autonomous system until the values ​​of all elements in the SID matrix and satellite node adjacency matrix of all satellites within the autonomous system are the same.

[0143] To reduce communication overhead, an incremental update mechanism is employed. Each satellite only sends the updated value of the element tuple in the satellite node adjacency matrix, along with the row and column of that element, to neighboring satellites within the same autonomous system. For example, (5,4,0,0) indicates that the value in the 5th row and 4th column of the satellite node adjacency matrix is ​​updated to the tuple (0,0), instead of sending the entire updated satellite node adjacency matrix to neighboring satellites. Each node that receives the updated values ​​of the elements in the SID matrix and satellite node adjacency matrix continues to forward this information to its other neighbors until the values ​​of all elements in the SID matrix and satellite node adjacency matrix within the autonomous system are synchronized.

[0144] S108. Within the same orbital layer, the boundary satellite nodes within each autonomous system (via the EGP protocol) synchronize and update the SID matrix and satellite node adjacency matrix with the boundary satellite nodes of other autonomous systems across regions; then, the boundary satellite nodes within each autonomous system synchronize and update the SID matrix and satellite node adjacency matrix of other autonomous systems with the satellite nodes within their own autonomous system, so that the values ​​of each element in the SID matrix and satellite node adjacency matrix of all satellites within the orbital layer are consistent.

[0145] S109. The boundary satellite nodes of each orbital layer synchronize the SID matrix and satellite node adjacency matrix within different orbital layers with the boundary satellite nodes of other orbital layers.

[0146] Figure 10This is a flowchart illustrating a satellite network routing path construction method according to another embodiment of the present invention. This embodiment provides a method for constructing satellite network routing paths within the same orbital layer, but it can also be used for constructing satellite network routing paths within different orbital layers.

[0147] like Figure 10 As shown in the figure, a satellite network routing path construction method in an embodiment of the present invention includes the following steps:

[0148] S201. The source satellite node queries the SID matrix for target satellite nodes that meet the service type requirements and remaining resource requirements through this node or the controller.

[0149] For example Figure 9 Satellite node 2 in orbital plane 6 requires heterogeneous computing services from CPU and GPU. This node determines the target satellite node that meets the requirements by querying the Service Type and Resource Availability fields in each extended SRv6 SID in the SID matrix through its own node or the controller. That is, satellite node 5 in orbital plane 4.

[0150] S202. The source satellite node determines the source satellite node and target satellite node numbers in the SID matrix through this node or the controller.

[0151] For example, the source satellite node is Figure 9 Satellite node 2 in orbital plane 6 is identified by its SID matrix number as (6-1)*5+2=27 according to the method described in S106. The target satellite node is... Figure 9 Satellite node 5 in orbital plane 4 of the satellite is numbered (4-1)*5+5=20 in the SID matrix according to the method described in S106.

[0152] S203. The source satellite node calculates the routing path through this node or the controller based on the source satellite node and the target satellite node's numbers in the SID matrix and the satellite node adjacency matrix.

[0153] One method for calculating routes is to minimize the overall link cost while ensuring that the time-to-live (TTL) of all links in the route path is within its validity period. When multiple target satellite nodes can meet the requirements of the source satellite node, the minimum overall link cost from the source satellite node to each target satellite node is calculated separately, and the route path with the minimum overall link cost is selected.

[0154] For example, Figure 9 The intermediate source satellite node is satellite node numbered 27 in the SID matrix, and the target satellite node is satellite node numbered 20 in the SID matrix. For example... Figure 9 As shown, assume the route calculation result is ele27→ele22→ele17→ele18→ele19→ele20.

[0155] S204. The source satellite node obtains the corresponding node extension SRv6 SID through the node number in the routing path calculation result by this node or the controller.

[0156] Assuming the node number in the route path calculation result is y, and n is the total number of rows in the SID matrix, the row number of the element in the corresponding SID matrix is ​​calculated using (y-1)mod n+1, where mod is the modulo operation. The column number of the element in the corresponding SID matrix is ​​calculated using floor((y-1) / n)+1, where floor() is the floor function. Then, based on the row and column numbers of the element in the SID matrix, the extended SRv6 SID of that node is obtained.

[0157] For example, the target satellite node is numbered 20, that is Figure 9 For the satellite node with the ID ele20, calculate the element in its corresponding SID matrix as (20-1) mod 5 + 1 = 5, and calculate the column of its corresponding SID matrix as floor((20-1) / 5) + 1 = 4. Query the value of the element in the 5th row and 4th column of the SID matrix to obtain the extended SRv6 SID of this node as 2001:db8:4:507::.

[0158] S205. The source satellite node sequentially fills the extended SRv6 SID of each node into the SRH extension header of this node through this node or the controller.

[0159] Figure 11 This diagram illustrates the SRH extension header format and its abstract format. Based on the route calculation result ele27→ele22→ele17→ele18→ele19→ele20, this path passes through 6 nodes. Therefore... Figure 11The value of n is 4 (counting from 0 and excluding the source node ele27). The Segment List contains SID[0], SID[1], SID[2], SID[3], and SID[4]. Among them, SID[4] is the SID of ele22, SID[3] is the SID of ele17, SID[2] is the SID of ele18, SID[1] is the SID of ele19, and SID[0] is the SID of ele20. For example, according to S204, the extended SRv6 SID of the satellite node with the number ele20 is 2001:db8:4:507::, then 2001:db8:4:507:: is filled into SID[0].

[0160] The present invention also provides a corresponding Figure 8 This is a satellite network topology discovery device. At the hardware level, this device includes a processor, internal bus, network interface, memory, and non-volatile memory, and may also include other hardware required for other services. The processor reads the corresponding computer program from the non-volatile memory into memory and then runs it to achieve the above-mentioned functionality. Figure 8 This invention presents a method for discovering the topology of inter-satellite computing satellite networks. Of course, besides software implementation, this invention does not exclude other implementation methods, such as logic devices or a combination of hardware and software. In other words, the execution entity of the following processing flow is not limited to individual logic units, but can also be hardware or logic devices.

[0161] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A method for discovering satellite network topology, characterized in that, Includes the following steps: S1: The controller assigns an extended SRv6 SID to each satellite according to the format of the extended SRv6 SID, and each satellite generates an initial extended SRv6 SID; the extended SRv6 SID consists of six fields: network prefix, orbital plane number, node number, service type, resource margin, and must be set to zero. S2: Divide the satellite network into different autonomous domains; S3: Each satellite obtains the initial extended SRv6 SID of other satellites in its orbital layer and determines the number of satellite orbital planes and the number of satellite nodes in each orbital plane in its orbital layer; S4: Establish a SID matrix for each satellite's orbital layer, and record the satellite's initial extended SRv6 SID in the SID matrix; S5: Each satellite establishes a satellite node adjacency matrix for its orbital layer, which is used to represent the communication link connection relationship between satellites within its orbital layer; S6: Each satellite senses its own resource status, updates the service type and resource balance fields in its extended SRv6 SID, and updates its extended SRv6 SID in the SID matrix; at the same time, each satellite periodically senses the link status with neighboring satellites within its orbital layer and updates the values ​​of the elements in the corresponding satellite node adjacency matrix. S7: Each satellite synchronizes its SID matrix and satellite node adjacency matrix with neighboring satellites within its autonomous system until the values ​​of all elements in the SID matrix and satellite node adjacency matrix of all satellites within the autonomous system are the same. S8: Within the same orbital layer, the boundary satellite nodes within each autonomous region first synchronize and update the SID matrix and satellite node adjacency matrix with the boundary satellite nodes of other autonomous regions across regions. Then, the boundary satellite nodes within each autonomous region synchronize and update the SID matrix and satellite node adjacency matrix of other autonomous regions with the satellite nodes within their own autonomous region, so that the values ​​of each element in the SID matrix and satellite node adjacency matrix of all satellites within the orbital layer are consistent. S9: The boundary satellite nodes of each orbital layer synchronize the SID matrix and satellite node adjacency matrix within different orbital layers with the boundary satellite nodes of other orbital layers.

2. The satellite network topology discovery method according to claim 1, characterized in that, The total length of the extended SRv6 SID is 128 bits; The service type field in step S6 is used to indicate whether the satellite node is suspending its service, or to indicate whether the satellite node provides a single service including forwarding, storage, and computing, or a heterogeneous service consisting of forwarding, storage, and computing.

3. The satellite network topology discovery method according to claim 1, characterized in that, In step S4, each satellite obtains the initial extended SRv6 SID of other satellites in its orbital layer in the following two ways: Method 1: The controller sends a message to each satellite to announce the initial extended SRv6 SID of other satellites in its orbital layer; Method 2: Each satellite discovers its neighbors within its orbital layer using internal gateway protocols and external gateway protocols, and exchanges initial extended SRv6 SIDs.

4. The satellite network topology discovery method according to claim 1, characterized in that, In step S5, the method for establishing the satellite node adjacency matrix for each satellite in its orbital layer is as follows: (1) Calculate the number of elements in the SID matrix N_ele=m*n based on the number of columns m and rows n of the SID matrix; (2) Establish a satellite node adjacency matrix with N_ele columns and rows. Each element in the satellite node adjacency matrix stores a tuple, namely (link, ttl), where link is 0 to indicate a broken link, link is a positive real number to indicate link cost, and ttl indicates the predicted duration of the communication link connection. The initial value of each element tuple is set to (0,0).

5. The satellite network topology discovery method according to claim 1, characterized in that, In step S6, in order to reduce frequent network signaling interactions, the corresponding extended SRv6 SID is updated in the SID matrix of the satellite only when the predicted service duration is greater than a preset time threshold or the resource reserve change is greater than a preset capacity threshold.

6. The satellite network topology discovery method according to claim 1, characterized in that, In step S6, the method for determining the elements in the corresponding satellite node adjacency matrix is ​​as follows: (1) First, number the elements in the SID matrix in ascending order of row number and then column number; (2) Convert the value of the node number field of the extended SRv6 SID to decimal and determine the row i of the extended SRv6 SID in the SID matrix; convert the value of the track surface number field to decimal and determine the column j of the extended SRv6 SID in the SID matrix; (3) Finally, calculate the number a of the extended SRv6 SID in the SID matrix element according to (j-1)*n+i, where n is the total number of rows in the SID matrix.

7. The satellite network topology discovery method according to claim 1, characterized in that, In step S6, updating the values ​​of the elements in the corresponding satellite node adjacency matrix specifically includes: When two satellites establish a link, if the ttl of the corresponding element tuple (link, ttl) in the current satellite node's adjacency matrix is ​​equal to 0, it indicates that the link is in a failed state. In this case, the link value is modified to a positive real number, where the value of the positive real number represents the link cost, and ttl is set to the predicted duration of the communication link connection. When two satellites establish a link, if the ttl of the corresponding element tuple (link, ttl) in the current satellite node adjacency matrix is ​​greater than 0, it indicates that the link is in a valid state. That is, the link connection state of the two satellites oscillates within the predicted duration of the communication link connection. If the link is broken and then re-established, the link value is only modified to a positive real number. The value of the positive real number represents the link cost. Once the link between two satellites is established, if the link status is continuously monitored multiple times, the value of the corresponding element tuple (link, ttl) will not be changed. Once the link between two satellites is established, if the link is broken in three consecutive link status sensing events, the value of link in the corresponding element tuple (link, ttl) will be modified to 0 to mark the link as broken. Once the link between the two satellites is established, when the TTL countdown reaches 0, the value of link in the corresponding tuple (link, ttl) is modified to 0 to mark the link as broken, and ttl is set to 0 to indicate that the link is in a failed state.

8. A method for constructing satellite network routing paths, characterized in that, This method is based on the network topology constructed by the satellite network topology discovery method described in claim 1, and includes the following steps: Step 1: The source satellite node queries the SID matrix for target satellite nodes that meet the service type requirements and remaining resource requirements through its own node or the controller; Step 2: The source satellite node determines the source satellite node and target satellite node numbers in the SID matrix through its own node or the controller; Step 3: The source satellite node calculates the routing path based on the source and target satellite node numbers in the SID matrix and the satellite node adjacency matrix through its own node or the controller; Step 4: The source satellite node obtains the extended SRv6 SID of the corresponding node through the node number in the routing path calculation result by itself or the controller; Step 5: The source satellite node fills the extended SRv6 SID of each node into the SRH extension header of its own node in sequence through its own node or the controller.

9. The satellite network routing path construction method according to claim 8, characterized in that, In step four, the method for obtaining the extended SRv6 SID of the corresponding node is as follows: (1) Calculate the row number of the corresponding element in the SID matrix according to (y-1)mod n+1, where y is the node number in the path calculation result, n is the total number of rows in the SID matrix, and mod is the modulo operation; The column number of the element in the corresponding SID matrix is ​​calculated based on floor((y-1) / n)+1, where floor() is the floor function. (2) Obtain the extended SRv6 SID of the node based on the row and column number of the element in the SID matrix.

10. A satellite network topology discovery device, characterized in that, The system includes a memory and one or more processors, wherein the memory stores executable code, and the one or more processors execute the executable code to implement the satellite network topology discovery method according to any one of claims 1-7.

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