Traffic distribution system and method based on path label routing for low earth orbit satellite networks

Abstract

The present invention relates to communication routing technology for low-orbit satellite networks, and more specifically, to a path label routing-based traffic distribution system and method for mitigating traffic concentration problems (hot spots) occurring in a dynamic network environment that changes moment by moment as multiple satellites orbit the Earth at high speeds.

Description

Technology Field

[0001] The present invention relates to communication routing technology for low-orbit satellite networks, and more specifically, to a path label routing-based traffic distribution system and method for mitigating traffic concentration problems (hot spots) occurring in a dynamic network environment that changes moment by moment as multiple satellites orbit the Earth at high speeds. Background Technology

[0002] Recently, low-orbit satellite networks have been attracting attention as a next-generation network infrastructure that forms a global communication network using hundreds to thousands of satellites. Low-orbit satellites orbit at high speeds in low-altitude orbits of approximately 200 to 2,000 km above the Earth's surface and are interconnected through Inter-Satellite Links (ISLs) to form a communication network that covers the entire globe. While this structure offers the advantages of low latency and real-time coverage of a wide area, it possesses a unique characteristic known as a dynamic topology, in which the network's connectivity changes moment by moment due to the continuous movement of the satellites.

[0003] In such environments, while the locations of ground terminals are generally fixed, the link configuration constantly changes due to satellite orbital movements. This leads to reduced path stability across the entire network and frequent occurrences of 'hot spot' phenomena, where traffic is concentrated on specific regions or satellites. Particularly in regions with high communication demand, such as the Korean Peninsula, excessive traffic concentration on certain satellites or links can degrade the overall network's service quality. Since existing shortest-path-based routing algorithms are designed based on the premise of a fixed network, their traffic distribution effectiveness is limited in environments with continuously moving nodes, such as satellites, and significant overhead occurs during the path convergence process. Prior art literature

[0004] (Patent Document 0001) KR 10-2024-0127357 A, 2024.08.22.(Patent Document 0002) KR 10-2019-0002672 A, 2019.01.08.(Patent Document 0003) KR 10-2022-0149305 A. 2022.11.08. The problem to be solved

[0005] The OPSPF (Orbit Prediction Shortest Path First) routing algorithm is designed to utilize the orbital regularity of a low-orbit satellite set to periodically calculate paths and efficiently reflect changes in network topology. This algorithm has the advantage of minimizing overhead during path convergence and responding relatively stably to regularly changing inter-satellite link connections. Furthermore, by integrating the dynamic link detection capabilities of OSPF (Open Shortest Path First), widely used in terrestrial networks, into an orbit-based static framework, it can also be applied in satellite communication environments.

[0006] However, the OPSPF method has structural limitations. This method is designed to calculate link states based on the position information of each satellite and periodically update routing tables using a shortest path algorithm. While this structure has the advantage of efficiently managing network topology information, overhead increases sharply because the entire routing information must be recalculated in the event of a link failure. In particular, in a clustered satellite network environment where many satellites are densely packed, the link state changes rapidly, leading to a problem where the path convergence speed is reduced and there is a high possibility of temporarily incorrect paths being formed.

[0007] Disruption Tolerant Distributed Routing (DTDR) is a routing method designed to reset routes without delay in the event of a link failure. In this method, each satellite detects the link status around it (up to a maximum range of n+1 hops) in real time and manages the Main Path, Alternate Path, and Detour Path in parallel. In the event of a link failure, it immediately switches to a pre-calculated Alternate Path or performs local load balancing by propagating failure information only to adjacent satellites. Through this structure, the cost of recalculating routes for the entire network is reduced, and by minimizing convergence delay, packet loss rates and transmission delays can be effectively improved.

[0008] However, since these DTDR methods also assume fixed orbital patterns or fixed link directionality, they are not optimized for actual satellite constellation operation environments or region-biased satellite network structures such as specific regional operations. Therefore, while existing OPSPF and DTDR-based routing technologies provide path prediction-based efficiency and fault tolerance, respectively, they have limitations in simultaneously satisfying link fault tolerance and traffic load distribution. Accordingly, there is a demand for lightweight source routing-based traffic distribution technology that can naturally distribute traffic load without complex control signals or global routing recalculation processes, while actively utilizing the path diversity inherent in orbit-based satellite networks. Such technology can improve the real-time operability and stability of satellite networks and contribute to securing stable communication quality even in constellation or region-biased satellite network environments.

[0009] Accordingly, the present invention is proposed to solve the problems of the prior art, and aims to provide a route label routing-based traffic distribution system and method for a low-orbit satellite network that can mitigate traffic concentration problems caused by the rapid orbit of satellites and link fluctuations in a low-orbit satellite network, as well as communication quality degradation caused by link failures. means of solving the problem

[0010] A traffic distribution system based on path label routing for a low-orbit satellite network according to an embodiment of the present invention includes: a satellite network unit that performs data transmission and reception between satellites and provides network operation information; a path control unit that calculates a path from a transmitting satellite to a destination satellite based on network operation information received from the satellite network unit and encodes the calculated path into label information; a routing control unit that includes the label information in a data packet and transmits it; a data forwarding unit that determines a transmission path for each hop unit by referring to the label information included in the data packet and collects telemetry information when transmitting a data packet according to the determined path; and a traffic distribution unit that analyzes the telemetry information and the network operation information to evaluate the network load status and feeds the result back to the path control unit and the routing control unit to perform load distribution.

[0011] Additionally, the network operation information may include at least one of link status, track information, or visibility information, and the telemetry information may include at least one of transmission delay, packet loss rate, or queue occupancy rate.

[0012] In addition, it may further include an exception handling unit that receives feedback information from the traffic distribution unit, and in the event of a link disconnection or quality degradation, refers to the feedback information to reset a local bypass path and corrects the label information to maintain the continuity of data transmission.

[0013] In addition, the path control unit may evaluate the availability of each link by referring to at least one of link status, orbit information, or visibility information, and calculate a path from the transmitting satellite to the destination satellite based on the evaluation result.

[0014] In addition, the path control unit encodes a label in either a short format or a long format according to the link characteristics of the calculated path, the short format encodes four directions—up, down, left, and right—in 2-bit units, and the long format encodes eight directions, including diagonal directions, in 4-bit units, and may include a satellite number corresponding to each direction.

[0015] In addition, the routing control unit can insert label information input from the path control unit into the packet header, establish a label-based path policy based on the label information, and transmit it to the routing unit and the data forwarding unit.

[0016] In addition, the data forwarding unit may determine a transmission path for each hop unit according to the control of the routing control unit and transmit telemetry information including at least one of a transmission delay, packet loss rate, or queue occupancy rate according to the transmission result to the traffic distribution unit.

[0017] In addition, the traffic distribution unit can analyze telemetry information from the data forwarding unit and network operation information from the satellite network unit to calculate a weight map for each link, and feed back the calculation result to the path control unit and the routing control unit.

[0018] In addition, when a link disconnection or quality degradation is detected, the exception handling unit can ensure the continuity of data transmission by referencing weight information provided by the traffic distribution unit to reset a local bypass path and modifying existing label information provided by the path control unit.

[0019] In addition, the traffic distribution unit can dynamically update link weights according to network load status and ensure that the updated weight information is reflected in the path calculation process of the path control unit.

[0020] In addition, the path label routing-based traffic distribution method for a low-orbit satellite network according to an embodiment of the present invention is a path label routing-based traffic distribution method for a low-orbit satellite network performed in a path label routing-based traffic distribution system for a low-orbit satellite network, comprising: (a) a process of collecting network operation information; (b) a process of calculating a path from a transmitting satellite to a destination satellite based on the network operation information and encoding the calculated path into label information; (c) a process of including the label information in a data packet and transmitting it; (d) a process of determining a transmission path for each hop unit by referring to the label information included in the data packet and collecting telemetry information while transmitting the data packet according to the determined path; and (e) a process of analyzing the collected telemetry information and the network operation information to evaluate the network load status and feeding the result back to the process of (b).

[0021] Additionally, the network operation information may include at least one of link status, track information, or visibility information, and the telemetry information may include at least one of transmission delay, packet loss rate, or queue occupancy rate.

[0022] In addition, if a link disconnection or quality degradation occurs, the process may further include resetting a local bypass path by referring to the feedback information obtained in the above process (e) and correcting the label information to maintain the continuity of data transmission.

[0023] In addition, the process of calculating the path in the above (b) process may evaluate the availability of each link by referring to at least one of the link status, orbit information, or visibility information among the network operation information, and calculate the path from the transmitting satellite to the destination satellite based on the evaluation result.

[0024] In addition, the process of encoding the path in the above (b) process encodes the label in either a short format or a long format according to the link characteristics of the calculated path, the short format encodes the four directions of up, down, left, and right in 2-bit units, and the long format encodes the eight directions including diagonal directions in 4-bit units and may include a satellite number corresponding to each direction.

[0025] In addition, the data packet transmitted in the above process (c) includes a label header and a label body, and the label header records the type, destination satellite ID and hop count, and the label body may record the direction of movement information and satellite number for each hop unit.

[0026] In addition, in the above process (d), telemetry information including at least one of transmission delay, packet loss rate, or queue occupancy rate for each home unit transmission result is collected, and said telemetry information can be reflected in the network load evaluation of the above process (e).

[0027] In addition, the above process (e) analyzes the telemetry information and the network operation information to calculate a weight map for each link, and feeds back the calculated weight information to the above process (b) to be reflected in path calculation and label policy determination.

[0028] In addition, the above bypass path resetting process can determine an alternative path on a local basis by referring to the load weight information calculated in the above (e) process for the section where a link disconnection or quality degradation is detected, and can continue packet transmission by modifying the above label information.

[0029] In addition, the above process (e) can be performed such that link weights are dynamically updated according to network load conditions, and the updated weight information is reflected in the path calculation and label encoding processes of the above process (b). Effects of the invention

[0030] As described above, according to the path label routing-based traffic distribution system and method for a low-orbit satellite network according to an embodiment of the present invention, transmission stability, real-time performance, and autonomous recovery capabilities can be secured by detecting problems such as delay, link disconnection, and load imbalance occurring in a low-orbit satellite network environment composed of multiple satellites in real time and actively controlling them.

[0031] First, according to an embodiment of the present invention, network operation information including link status, orbit information (position, orbit plane, etc.), and visibility information is continuously collected and updated through a satellite network unit, thereby enabling precise monitoring of the status of links between each satellite. Accordingly, unlike conventional routing techniques based on periodic table updates, a routing structure that actively responds to real-time network status changes (link loss, increased latency, etc.) can be implemented.

[0032] Second, according to an embodiment of the present invention, the path control unit calculates an optimal path from a transmitting satellite to a destination satellite based on such network operation information, and by encoding the calculated path into label information, the intermediate satellite node can immediately determine the next hop without looking up a complex routing table. Accordingly, the burden of path calculation is significantly reduced, and routing delay of the entire network can be minimized.

[0033] Third, according to an embodiment of the present invention, the label encoding method is divided into a short format and a long format and is flexibly applied depending on the complexity of the network topology or the failure state. The short format is encoded as a simple sequence of directions in regular link sections to increase transmission efficiency, and the long format includes diagonal direction and satellite number information, enabling accurate path control even in failure sections or unstructured link environments. This effectively overcomes the geometric asymmetry of low-orbit satellite networks and the temporal variability of link visibility.

[0034] Fourth, according to an embodiment of the present invention, the data forwarding unit transmits actual packets in accordance with the command of the routing control unit, and at the same time collects telemetry information such as transmission delay, packet loss rate, and queue occupancy rate in real time and transmits (reports) it to the traffic distribution unit. The traffic distribution unit comprehensively analyzes the collected telemetry information and operational information input from the satellite network unit to calculate a weight map for each link, and feeds the results back to the path control unit and the routing control unit so that they are reflected in the calculation of the next path and the determination of the label policy. Through this, the load balancing of the entire network can be dynamically maintained.

[0035] Fifth, according to an embodiment of the present invention, when a link disconnection or quality degradation is detected, the exception handling unit refers to weight information fed back from the traffic distribution unit to immediately reset a bypass path at the local level and modifies (corrects) existing label information to continue data transmission. Therefore, local-based exception handling is possible, which can autonomously perform recovery at the local level without the intervention of a central control node for link recovery. Brief explanation of the drawing

[0036] FIG. 1 is a diagram showing the configuration of a path label routing-based traffic distribution system for a low-orbit satellite network according to an embodiment of the present invention. FIG. 2 is a diagram showing an example of a label structure generated by the path control unit of FIG. 1. FIG. 3 is a diagram showing the format of the label header and label body of a label generated by the path control unit of FIG. 1. FIG. 4 is a diagram showing an example of the operation characteristics of the routing unit shown in FIG. 1. FIG. 5 is a flowchart illustrating a path label routing-based traffic distribution method for a low-orbit satellite network according to an embodiment of the present invention. FIGS. 6 to 8 are drawings illustrating the operation process of a path label routing-based traffic distribution method for a low-orbit satellite network according to an embodiment of the present invention shown in FIG. 5. Specific details for implementing the invention

[0037] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms, and the embodiments of the present invention are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention. In the drawings, like reference numerals refer to like elements.

[0038] While routing methods such as OPSPF or DTDR according to conventional technology have demonstrated certain performance in terms of delay optimization and fault recovery, they have limitations in that they cannot sufficiently resolve traffic bias and downlink bottlenecks in region-specific clustered satellite network environments with complex terrain and high operational density, such as the Korean Peninsula. Accordingly, the embodiments of the present invention provide a lightweight source routing-based traffic distribution technique that integrates the concepts of existing algorithms and simultaneously secures link fault recovery and load distribution efficiency. In particular, when a link disconnection occurs at a specific node on a satellite network, a region-based exception handling mechanism is provided that resets the next hop at the local level using matrix-based destination directionality ('weight' information). Through this, the continuity of the existing source path and the stability of data transmission can be simultaneously secured. Therefore, unlike conventional path selection methods that simply search for the shortest path, the embodiments of the present invention can provide a practical routing system that dynamically configures a path capable of detouring and recovery, thereby improving the real-time performance, stability, and reliability required for the operation of clustered low-orbit satellite networks.

[0039] FIG. 1 is a block diagram schematically illustrating the configuration of a path label routing-based traffic distribution system for a low-orbit satellite network according to an embodiment of the present invention.

[0040] Referring to FIG. 1, a path label routing-based traffic distribution system (10, hereinafter referred to as the "system") for a low-orbit satellite network according to an embodiment of the present invention comprises: a satellite network unit (11) that performs data transmission and reception between satellites and provides link status and orbit information between satellites; a path control unit (12) that calculates an optimal path to a destination based on link quality and visibility information collected from the satellite network unit (11); a routing control unit (13) that establishes a label-based path policy by referring to the calculation result of the path control unit (12) and network load feedback information, and generates and manages label information that encodes the transmission path to the destination in the form of a bit sequence according to the label-based path policy; a routing unit (14) that receives a data packet containing the label information, determines a transmission path for each hop unit using the label information, and routes the data packet; a data forwarding unit (15) that actually transmits the data packet according to the control of the routing unit (14) and collects network operation information such as transmission delay, loss rate, and queue status; and a network that analyzes telemetry collected from the data forwarding unit (15). It includes a traffic distribution unit (16) that evaluates the overall load status and dynamically performs load distribution by feeding the results to a path control unit (12) and a routing control unit (13), and an exception handling unit (17) that, when an exception occurs such as a link disconnection or quality degradation, immediately resets a bypass path at the local level by referring to information from the routing control unit (13) and the traffic distribution unit (16) and ensures the continuity and reliability of data transmission.

[0041] The satellite network unit (11) is a data transmission layer that performs the transmission and reception of actual data packets through an Inter-Satellite Link (ISL) with an adjacent satellite, and performs real-time data transmission and link status monitoring functions in parallel in a lightweight source routing-based traffic distribution structure. This satellite network unit (11) receives a forwarding command for "next hop direction" or "next satellite number" from the data forwarding unit (15), transmits data through the corresponding ISL port, and, if necessary, applies a link usage control command (e.g., temporary blocking, bypassing, reassignment, etc.) transmitted from the path control unit (12) or the exception handling unit (17) to avoid sections where failures or congestion are detected. In this process, the satellite network unit (11) continuously measures the link status and provides the results in real-time to the traffic distribution unit (16) and the data forwarding unit (15), thereby supporting the upper layer to quickly perform load adjustment and bypass judgments.

[0042] The satellite network unit (11) continuously measures link status through ISL with adjacent satellites and operates as an active network node that supports traffic distribution and region-based exception handling. For example, it generates telemetry information by measuring ISL quality indicators in real time, such as link up / down status, BER (Bit Error Rate), RTT (Round Trip Time), delay distribution, packet drop rate, and queue occupancy, and constructs network operation information by combining orbit information such as the satellite's orbit plane, slot position, and time-to-leave / enter window. The network operation information thus constructed is provided to the path control unit (12) and the traffic distribution unit (16). The path control unit (12) refers to network operation information and uses it as auxiliary data when calculating an optimal path based on lightweight source routing, and the traffic distribution unit (16) calculates the load balance (weight map) of the entire network based on real-time telemetry data directly input from the satellite network unit (11), and feeds the calculated weight information to the path control unit (12) and the routing control unit (13) so that the path selection and label policy are dynamically adjusted according to the link load.

[0043] The satellite network unit (11) internally includes an ISL interface unit and a label processor unit. The ISL interface unit performs transmission and reception with adjacent satellites at the physical and link layer levels and is responsible for link quality measurement and signal synchronization functions. The label processor unit secures a low-latency packet delivery path by rapidly interpreting the direction code or next satellite number input from the data forwarding unit (15) or the exception handling unit (17) and immediately executing a transmission command through the corresponding ISL port. Therefore, the satellite network unit (11) provides a foundation that goes beyond simply executing a path calculated by the upper control layer and can autonomously execute a feedback path at a local level even in the event of a link failure or quality degradation. Through this, the embodiment of the present invention can realize a localized exception handling structure that can rapidly detect and bypass a failure section without the process of recalculating the entire path between satellites. In addition, by adjusting the link load in real time through mutual interaction with the traffic distribution unit (16), a practical routing system based on lightweight source routing can be implemented to simultaneously secure link failure recovery and load distribution efficiency.

[0044] The path control unit (12) is a source routing-based path calculation module that calculates the optimal path to the destination at the time of transmission, encapsulates it into a label, and provides it to the routing control unit (13). As input, it receives summarized network operation information such as link availability, average delay, BER, and time-to-leave / enter provided by the satellite network unit (11) and the data forwarding unit (15), as well as selection weight and avoidance priority information for each candidate path calculated by the traffic distribution unit (16). Based on these input values, the path control unit (12) calculates the optimal path sequence to the destination within the entire satellite network by integrating the link status and load weight.

[0045] FIG. 2 is a schematic diagram showing an example of a label structure generated in the path control unit of FIG. 1, and FIG. 3 is a schematic diagram showing the format of the label header and label body of the label generated in the path control unit of FIG. 1.

[0046] Referring to FIGS. 1 to 3, the path control unit (12) calculates an optimal path to a destination based on link quality information and orbit information collected from the satellite network unit (11) and encodes the result in the form of a label. At this time, the path control unit (12) selects and labels the calculated path as either a Long type or a Short type, as shown in FIG. 2, according to the characteristics of the inter-satellite link (e.g., fault section, boundary area, topology complexity, etc.).

[0047] As shown in FIG. 3, the label is largely composed of a label header and a label body, and each field contains information necessary for transmission path designation and forwarding control. The label header is a high-level management field for packet identification and transmission control, and consists of the following three items. Type (1 bit) indicates the type classification of the label, where '0' signifies a Short type and '1' signifies a Long type. Destination Satellite ID (10 bits) is a field that specifies the unique identification number of the destination satellite. Hop Count (5 bits) indicates the number of hops the packet must pass through and is dynamically set according to the length of the path. This header information is used as basic management data to identify where the packet should currently be headed at the intermediate satellite node. The label body defines the actual movement path information for each hop unit and includes the direction of movement and the satellite number information corresponding to that direction. Label Direction (4 bits) represents the direction of movement of the next hop using a 4-bit code. Each bit combination represents a direction, such as Up (0000), Down (0011), Left (0010), Right (0001), UpLeft (0110), UpRight (0101), DownLeft (1110), and DownRight (1101). Through this 8-direction encoding, not only vertical and horizontal movement but also diagonal movement can be represented. The Satellite Number (14 bits) is a field that specifies the identification number of the actual next satellite corresponding to the direction code. This exists for each hop and is mandatory for long type labels.

[0048] Accordingly, the label body is configured in pairs of "Label Direction (4 bits) / Satellite Number (14 bits)", and the entire path can be expressed as a sequence of these pairs. For example, it can be expressed as "U(0000)-12, R(0001)-22, U(0000)-23, R(0001)-33, U(0000)-34, U(0000)-35, R(0001)-45". According to this structure, label information is generated in the path control unit (12) and transmitted to the routing control unit (13), and the routing control unit (13) inserts the corresponding label information into the header of the data packet and transmits it. Subsequently, the intermediate satellite node can interpret the direction code and satellite number recorded in the label body and immediately select the ISL port of the next hop without looking up a complex routing table. Accordingly, real-time routing is possible even in low-orbit satellite network environments where inter-satellite link fluctuations are frequent, and lightweight bit-unit encoding enables reduced control load, minimized latency, and rapid fault avoidance.

[0049] The routing control unit (13) is a label management and path policy control module for receiving label information calculated from the path control unit (12) and applying it to actual packet routing, and manages packet-unit transmission paths based on the label header and label body of the label information input from the path control unit (12). In this process, if the path calculated by the path control unit (12) does not match the real-time load condition of the network, the path policy is dynamically adjusted at the time of packet transmission by reflecting the encapsulated destination weight information of the path control unit (12). At this time, the routing control unit (13) applies different processing methods depending on the Type (Short / Long) field. In the case of the short format, only the movement direction of each hop is referenced in 2-bit units and transmitted to the routing unit (14), and in the case of the long format, detailed path information consisting of a direction code (Label Direction, 4 bits) and a satellite number (Satellite Number, 14 bits) is interpreted to perform explicit hop-unit forwarding control.

[0050] The routing control unit (13) inserts the label information encoded by the path control unit (12) into the packet header area and transmits it to the data forwarding unit (15). During this process, a label integrity check is performed to ensure that the Hop Count, Destination Satellite ID, and Type fields are recorded correctly. The packet, once encapsulated, is transmitted to the routing unit (14), and the routing unit (14) determines the transmission path for each hop by referring to the corresponding label information. For reference, the path control unit (12) calculates the optimal path to the destination based on link status and load information collected from the satellite network unit (11) and the traffic distribution unit (16), as well as prediction data such as the visibility window, and performs an encoding process to convert this path into a label bit sequence.

[0051] The routing control unit (13) refers to the label information included in the packet and issues a transmission instruction to the routing unit (14). The routing unit (14) executes the actual transmission path according to the instruction. Whenever a packet is received, the routing unit (14) sequentially reads the Label Direction and Satellite Number recorded in the label body and determines the ISL port (link port) to move from the current hop to the next hop. When forwarding is completed, the Hop Count is automatically decreased, and if it matches the Destination Satellite ID, the data packet is considered to have reached the final destination. The routing control unit (13) can transmit operational information such as forwarding delays, retransmission attempts, and link failure events occurring during this process to the traffic distribution unit (16) and the exception handling unit (17) to support dynamic control and fault recovery of the entire network in real time.

[0052] The routing control unit (13) maintains consistency and adaptability of the path policy through organic data exchange with the path control unit (12). The path control unit (12) calculates the optimal path based on orbit prediction, time-to-leave / enter, quality requirements, etc., and provides the result to the routing control unit (13). The routing control unit (13) determines the packet routing policy by adjusting it to the real-time network operating environment (link availability, traffic load). Through this combined structure, the path control unit (12) is responsible for "prediction-based static path calculation," and the routing control unit (13) performs "real-time dynamic policy application," thereby implementing a hybrid routing structure that satisfies accuracy and adaptability.

[0053] The routing unit (14) is a module that performs actual transmission of packets through the data forwarding unit (15) by decoding label information received from the routing control unit (13) and determining the transmission direction or next satellite number for each hop unit, and by utilizing the path information encoded in the path control unit (12), it enables rapid forwarding decisions by referring only to the bit sequence recorded in the label without complex path calculations or table lookups at intermediate satellite nodes.

[0054] As input to the routing unit (14), a data packet containing a label header and a label body transmitted from the routing control unit (13) is provided, and the corresponding label information consists of a bit sequence of direction information or satellite number for each hop unit along with control fields such as "Type (Short / Long), Destination Satellite ID, Hop Count". Based on this label information, the routing unit (14) selects the ISL port to be transmitted to the next hop by comparing it with the current satellite's position coordinates (e.g., orbit plane number, slot position, etc.). For example, if the label body is set to "Up (0000)", the uplink port is activated, and if it is "Right (0001)", ISL transmission to the adjacent right satellite is performed. At this time, forwarding control is executed immediately at the physical link end through the data forwarding unit (15). The routing unit (14) can perform dynamic correction in conjunction with network operation information (e.g., transmission delay, packet loss rate, queue occupancy rate, etc.) collected from the data forwarding unit (15). For example, if congestion occurs in an ISL link in a specific direction, the routing unit (14) transmits a feedback signal to the routing control unit (13), and the routing control unit (13) combines this with load weight information from the traffic distribution unit (16) to readjust the path policy. Through this feedback loop, the routing unit (14) performs adaptive routing in real time and can achieve network congestion avoidance and delay minimization.

[0055] Figure 4 is a diagram illustrating the operation of the routing unit shown in Figure 1, and is a diagram schematically showing a four-way communication structure between adjacent satellites in a grid-type low-orbit satellite network.

[0056] Referring to FIG. 4, the routing unit (14) operates based on a four-way (up / down / left / right) communication structure between adjacent satellites in a grid-type low-orbit satellite network. The central satellite node is connected to adjacent satellites through four-way ISLs: up (Vertical Up), down (Vertical Down), left (Horizontal Left), and right (Horizontal Right). These four directions are mapped to the direction codes of the short-type labels encoded by the path control unit (12), namely Up (0000), Down (0011), Left (0010), and Right (0001), respectively. The routing unit (14) determines the transmission direction to the next hop by directly referencing these direction codes. For example, if the first bit sequence recorded in the label body of a received data packet is "Right(0001)", the routing unit (14) interprets the information to activate the right-direction ISL link and issues a transmission instruction to the data forwarding unit (15) through the activated ISL link port. Since no separate routing table search or path recalculation is performed during this process, real-time forwarding is achieved while minimizing the delay caused by path calculation. Additionally, the routing unit (14) monitors network operation information (e.g., link utilization, delay, loss rate, queue occupancy rate, etc.) collected from the data forwarding unit (15) in real time and feeds it back to the traffic distribution unit (16) and the routing control unit (13). This feedback information is utilized for traffic load balancing (weight map) and link status evaluation and is reflected when establishing the next label-based path policy. That is, the routing unit (14) performs hop-unit routing with almost no delay based on label information encoded in the path control unit (12) and ensures real-time transmission quality through close coordination with the data forwarding unit (15). Through this, the excessive path recalculation load that occurs in conventional centralized routing techniques is significantly reduced, and high transmission stability and low latency can be secured even in a grid-type low-orbit satellite network environment.

[0057] The data forwarding unit (15) receives a data packet containing label information transmitted from the routing unit (14) and performs a transmission operation based on the label information. The data forwarding unit (15) determines the transmission direction of the packet using the next hop information determined by the routing unit (14), and provides a basis for judgment for the traffic distribution unit (16) and the exception handling unit (17) by measuring and reporting various network status information occurring during transmission in real time.

[0058] The data forwarding unit (15) reads the label header and label body of the received packet to determine the transmission direction to be performed at the current hop. The label header includes the label format, destination satellite ID, and number of intermediate hops, and the label body sequentially records the direction of movement or satellite number for each hop unit. The data forwarding unit (15) interprets this information and operates as follows. In the case of a short-type label, one of the four directions—Up, Down, Left, and Right—is interpreted as a 2-bit direction code to activate the ISL port of the corresponding direction. In the case of a long-type label, the 4-bit direction code and 14-bit satellite number information are combined to perform transmission to the designated satellite number. In this process, the data forwarding unit (15) minimizes hop-unit delay by executing transmission by referencing only the bit sequence of the packet header without performing complex path recalculation or routing table search.

[0059] Additionally, the data forwarding unit (15) measures link quality and network operation information in real time during packet transmission. For example, indicators such as RTT (Round Trip Time) per port, average delay, packet loss rate, queue occupancy, and throughput are continuously calculated, and this network operation information is transmitted to the traffic distribution unit (16) and used as a basis for link-specific load balancing (weight map) and path weight adjustment. Furthermore, if abnormal situations such as momentary link disconnection, exceeding the retry limit, or a sudden increase in delay are detected, the information is transmitted to the exception handling unit (17) so that local reroute can be executed.

[0060] In this way, the data forwarding unit (15) performs actual data transmission based on label information transmitted from the routing unit (14), while simultaneously exchanging transmission quality, link status, and delay information in real time through a feedback loop with the traffic distribution unit (16) and the exception handling unit (17). Through this, the traffic distribution unit (16) can accurately reflect the load status of the entire network, and the exception handling unit (17) can quickly apply a bypass path in the event of a failure.

[0061] The traffic distribution unit (16) analyzes the load status of the entire satellite network based on network operation information collected in real time from the data forwarding unit (15) and dynamically controls the traffic distribution policy for each path. That is, it comprehensively evaluates various operational indicators such as the availability of inter-satellite links, average delay, packet loss rate, and queue occupancy rate to recalculate the weight of each path, and feeds this back to the path control unit (12) and the routing control unit (13) to simultaneously secure real-time traffic load balancing and network stability.

[0062] The traffic distribution unit (16) operates in the following manner.

[0063] First, link quality and forwarding performance data (e.g., link availability rate, RTT, congestion rate, queue occupancy rate, drop rate, etc.) reported periodically or on an event basis from the data forwarding unit (15) are collected. At this time, the data forwarding unit (15) provides hop-unit micro-delay and transmission success rates, and the satellite network unit (11) provides orbital position information. The traffic distribution unit (16) integrates this information to form a weight map of the load status of the network.

[0064] Second, based on the collected operational information, load weights and avoidance priorities are calculated. In this process, the traffic distribution unit (16) performs a dynamic weight correction algorithm that deducts the path weight of a section when an overload is concentrated in a specific section or delays increase rapidly, and compensates for the weight of a relatively safe path. Additionally, by reflecting link failure and recovery events transmitted from the exception handling unit (17), temporarily unstable links are avoided or the recovered section is reorganized into a priority path.

[0065] Third, the calculated load weights and avoidance rules are transmitted to the path control unit (12) and the routing control unit (13), and are reflected in the label-based path policy that these modules will generate in the future. Through this, newly generated data packets are set to a weighted dynamic path that considers the load distribution of the entire network, instead of a simple shortest path.

[0066] Fourth, the traffic distribution unit (16) continuously exchanges its own calculation results with the data forwarding unit (15) and the exception handling unit (17) through a real-time feedback loop. For example, if the delay of a specific link in the data forwarding unit (15) rises sharply or the packet loss rate exceeds a threshold, the traffic distribution unit (16) detects this, immediately designates it as an avoidance section, and transmits the avoidance priority information of the corresponding link to the exception handling unit (17). Conversely, if the exception handling unit (17) successfully performs a local reroute, the result is transmitted to the traffic distribution unit (16) and the weight map is updated.

[0067] Through this mutual feedback structure, the system (10) can autonomously correct situations of link disconnection, congestion, or delay imbalance without recalculating the global path. In this way, the traffic distribution unit (16) operates as a distributed network autonomous adjustment module that controls the traffic flow of the satellite in real time. In particular, in a clustered low-orbit satellite environment, the load condition changes moment by moment due to changes in the link's visibility window and topology variations caused by orbital movement; the traffic distribution unit (16) enables continuous network balance maintenance and efficient resource utilization by periodically updating weights to reflect these variations.

[0068] The exception handling unit (17) is a local-based exception handling module that locally detects and immediately recovers from exceptional situations such as link disconnection, quality degradation, and delay surge that inevitably occur in a low-orbit satellite network. Based on real-time network operation information transmitted from the data forwarding unit (15) and the traffic distribution unit (16), it recognizes the occurrence of a failure section and sets a bypass path at the local level, thereby simultaneously ensuring the continuity of data transmission and the stability of the network.

[0069] The exception handling unit (17) performs the following step-by-step functions.

[0070] First, the data forwarding unit (15) immediately notifies the exception handling unit (17) of the event if a phenomenon such as an ISL link disconnection, a retry exceeding limit, a surge in RTT, or an over-saturation of queue occupancy occurs during packet transmission. At this time, the event may include information on the location of the failure (satellite ID / link ID), the cause of the failure (physical disconnection, congestion, temporary delay, etc.), the time of occurrence, and the duration.

[0071] The exception handling unit (17) updates the failure status table immediately upon receiving such events to manage the failure area and normal path of the current network separately. The exception handling unit (17) controls local rerouting to be performed at the node immediately preceding the failure section or at an adjacent satellite. The rerouting method used at this time is distinguished according to the label format. In the case of a short-type label, the direction code corresponding to the failure section is immediately replaced with the most similar alternative direction (e.g., 'R→U', 'D→L', etc.) using a predefined weight matrix. This replacement is applied locally only at the 1-2 hop level, maintaining the continuity of the entire path. In the case of a long-type label, the satellite number corresponding to the next hop of the failure section is replaced with a predefined alternative node to perform an explicit hop switching. This enables stable packet delivery even in unstructured link structures or boundary areas. At this time, the exception handling unit (17) selects an alternative path with the shortest distance or minimum delay within a range that does not violate the path policy defined by the routing control unit (13).

[0072] After determining the re-path, the exception handling unit (17) verifies the integrity and hop consistency of the modified label. That is, it checks whether the modified label is directed toward the original destination satellite ID, whether the reduction in the hop count is properly reflected, or whether there is no possibility of a loop occurring. If necessary, the inconsistent label is discarded or a new label is requested again. Through this verification process, unstable retransmission or path loop problems can be prevented in advance.

[0073] The exception handling unit (17) immediately reports the result of applying the local bypass path to the traffic distribution unit (16). For example, feedback such as a recovery path, delay change, and packet loss rate is provided in the form of "link (23↔33) disconnected → alternative path (23↔24↔34↔33) applied". Based on this information, the traffic distribution unit (16) recalculates the load weight and reflects it in the path control unit (12) and the routing control unit (13) to alleviate the load on the same section in the future. When the fault section is restored, the exception handling unit (17) switches the state of the corresponding link back to normal and restores the label information that was temporarily modified to the original label sequence. This process is performed through signal exchange with the data forwarding unit (15), and upon completion of restoration, the section is included again as a path candidate by the traffic distribution unit (16).

[0074] FIG. 5 is a schematic flowchart illustrating a path label routing-based traffic distribution method for a low-orbit satellite network according to an embodiment of the present invention.

[0075] Referring to FIGS. 1 and FIGS. 5, first, network operation information is collected (S1). The satellite network unit (11) generates network operation information by measuring link status, latency, packet loss rate, queue occupancy, orbit and visibility information, etc., in real time through ISL with adjacent satellites.

[0076] Meanwhile, the data forwarding unit (15) measures transmission layer operational data, such as transmission delay time, packet loss rate, queue occupancy rate, and retransmission rate, during the process of transmitting actual packets under the control of the routing unit (14), and compiles this into auxiliary telemetry information. The auxiliary telemetry information thus compiled is reported to the traffic distribution unit (16) and the path control unit (12) as data reflecting the actual traffic status of the network. The network operational information collected and integrated in this way is used as input data for calculating the optimal path in the path control unit (12), and is used as basic data for calculating network load balance and adjusting path weights in the traffic distribution unit (16).

[0077] Next, path calculation and label encoding are performed (S2). The path control unit (12) receives network operation information provided by the satellite network unit (11) and the data forwarding unit (15) and comprehensively evaluates the availability, latency, visibility, and load status of each link. Based on the evaluation results, it calculates the optimal path to the destination satellite and encodes the label by classifying it into a short format or a long format according to the link characteristics. For example, the short format is applied to sections where there are no failures and the link structure is regular, and consists of a simple direction sequence in which the four directions of Up, Down, Left, and Right are encoded in 2-bit units. On the other hand, the long format is applied to sections with failures, boundary areas, or irregular satellite connection sections, and represents eight directions including diagonal directions in 4 bits, and includes the satellite number corresponding to each direction, thereby enabling accurate path designation even in complex link environments. The path control unit (12) encodes the label header and label body according to the selected format. The label header includes management fields such as format (Short / Long), destination satellite ID, and number of transit hops, and the label body sequentially records movement direction codes or satellite number information for each hop unit. The completed label information is transmitted to the routing control unit (13), and then inserted into the packet header at the data forwarding unit (15) for actual transmission. Through this path calculation and encoding process, the path can be optimized in real time according to changes in the link status of the network, and the satellite network can achieve latency reduction, improved stability, and traffic balancing.

[0078] Next, routing and forwarding are performed (S3). The routing control unit (13) inserts the encoded label information transmitted from the path control unit (12) into the header of the data packet and transmits the packet to the routing unit (14). The routing unit (14) interprets the label header and the label body to determine the direction of movement of the current hop or the next satellite number, and transmits the determined information to the data forwarding unit (15). The data forwarding unit (15) selects the corresponding ISL port according to the direction information input from the routing unit (14) and transmits the actual packet to the designated adjacent satellite. Transmission results such as delay time, packet loss rate, link status, and queue occupancy rate occurring during the transmission process are collected as telemetry data and reported in real time to the traffic distribution unit (16) and the path control unit (12). Through this, the packet can be rapidly forwarded based on the bit sequence recorded in the label without separate path calculation at the intermediate satellite node. Therefore, compared to existing link-state routing methods, control signals and computational load are significantly reduced, and real-time performance and transmission reliability can be secured through label control based on lightweight source routing.

[0079] Next, load analysis and weights are fed back (S4). The traffic distribution unit (16) integrates and analyzes telemetry information periodically reported from the data forwarding unit (15). Through this, the load status and congestion level of each link are quantitatively evaluated, and a weight map is calculated for load balancing across the network. The calculated weights are updated in real time to reflect changes in network topology and link status, and this updated weight information is fed back to the path control unit (12) and the routing control unit (13) to be reflected in future path calculation and label policy determination. In particular, the traffic distribution unit (16) can efficiently alleviate traffic concentration problems (hot spots) and downlink bottlenecks by dynamically adjusting penalty coefficients for congested links to control traffic distribution to links that are relatively spare among multiple paths. This weight feedback loop process is continuously linked with the path control unit (12) and the routing control unit (13) to automatically correct the path policy according to network operation conditions. Therefore, the traffic distribution efficiency, transmission reliability, and real-time adaptability of the entire low-orbit satellite network can be improved.

[0080] Next, fault detection and region-based exception handling are performed (S5). When the data forwarding unit (15) detects abnormal state changes in real time, such as delay congestion, packet drops, or link disconnection during transmission, it immediately notifies the exception handling unit (17) of the relevant information. The exception handling unit (17) refers to the link weight map and load status feedback information periodically provided by the traffic distribution unit (16) to reset the local bypass route for the section where the fault occurred. In this process, the exception handling unit (17) controls the packet to be delivered normally to the next hop without retransmission by dynamically modifying or correcting the existing label information. The newly corrected label is retransmitted to the routing control unit (13) and the data forwarding unit (15) and is immediately reflected, and the forwarding operation continues without interruption. Through this structure, the system (10) according to the embodiment of the present invention can quickly bypass the fault section without a centralized calculation procedure, and as a result, transmission continuity and service reliability can be maintained even in situations of inter-satellite link disconnection or temporary quality degradation.

[0081] FIGS. 6 to 8 are drawings illustrating the operation process of a path label routing-based traffic distribution method for a low-orbit satellite network according to an embodiment of the present invention shown in FIG. 5.

[0082] FIG. 6 is a diagram visually illustrating the process of performing the path calculation and label encoding (S2) process shown in FIG. 5 on an actual satellite network, and is a diagram exemplifying the basic transmission path from the transmitting satellite (11) to the destination satellite (45). As shown in FIG. 6, in a low-orbit satellite network configured in a grid shape, the transmitting satellite (11) reaches the destination satellite (45) by sequentially following the up and right links through the path “U→R→U→R→U→U→R”. In this process, the path control unit (12) comprehensively analyzes link availability, visibility, delay, and congestion information provided by the satellite network unit (11) to calculate the path as the optimal path, and the routing control unit (13) encodes this path information in a label format.

[0083] FIG. 7 is a diagram showing a specific structure in which the path calculated in FIG. 6 is encoded into a long-type label. As shown in FIG. 7, the encoded label includes a label header and a label body. The label header includes management fields such as the format (Type=1, Long Type), destination satellite ID (Destination Satellite ID=45), and hop count (Hop Count=7), and the label body sequentially records the direction of movement (U, R, etc.) for each hop unit and the corresponding satellite number (12, 22, 23, 33, 34, 35, 45). The label information generated in this way is inserted into the header of a data packet and transmitted through a network, and intermediate satellite nodes determine the next hop (ISL port) by interpreting only the bit sequence of the corresponding label without querying a routing table. Accordingly, the routing structure according to an embodiment of the present invention can eliminate path recalculation delays and control traffic that occurred in the existing link-state-based method.

[0084] FIG. 8 is a diagram illustrating a region-based exception handling and traffic recovery process according to an embodiment of the present invention. FIGS. 8(a) to (d) sequentially illustrate the steps of link failure detection, bypass path search, label correction, and data transmission recovery. For example, as shown in FIG. 8(a), if a disconnection occurs in an intermediate section of the transmission path (e.g., link 33-34), the data forwarding unit (15) immediately reports the event to the exception handling unit (17). The exception handling unit (17) searches for adjacent link candidates that can avoid the failure section by referring to the latest weight map information provided by the traffic distribution unit (16), and selects the most suitable alternative path by comparing and analyzing the destination ID of the label header and the path information of the label body (11→12→22→23→33→34→35→45). The selected alternative path is updated by partially correcting the direction code and satellite number of the label, and the corrected label is immediately forwarded to the data forwarding unit (15) so that packet transmission can continue without interruption. As shown in FIG. 8 (b) to (d), even if a failure point occurs at a different location within the network, each node performs a real-time autonomous recovery function by searching for and recovering a local bypass path in the same way.

[0085] As such, FIGS. 6 to 8 are diagrams that sequentially explain a series of processes from the path calculation and label encoding process (S2) shown in FIG. 5 to the fault detection and exception handling process (S5). Through this method, intermediate satellite nodes are configured to autonomously perform routing and recovery using only the label information generated at the transmitting node, thereby simultaneously securing the real-time capability, reliability, and autonomous recovery required in a low-orbit satellite network environment.

[0086] In the foregoing, preferred embodiments of the present invention have been described and illustrated using specific terms, but such terms are intended solely to clarify the invention, and it is obvious that various modifications and changes may be made to the embodiments and terms described without departing from the technical spirit and scope of the following claims. Such modified embodiments should not be understood separately from the spirit and scope of the present invention, but should be considered to fall within the scope of the claims of the present invention. Explanation of the symbols

[0087] 10 : System 11 : Satellite Network 12: Path control unit 13: Routing Control Unit 14: Routing section 15 : Data Forwarding Section 16: Traffic Distribution Unit 17: Exception Handling Section

Claims

Claim 1 A route label routing-based traffic distribution system for a low-orbit satellite network comprising: a satellite network unit that performs data transmission and reception between satellites and provides network operation information; a route control unit that calculates a path from a transmitting satellite to a destination satellite based on network operation information received from the satellite network unit and encodes the calculated path into label information; a routing control unit that includes the label information in a data packet and transmits it; a data forwarding unit that determines a transmission path for each hop unit by referring to the label information included in the data packet and collects telemetry information when transmitting a data packet according to the determined path; and a traffic distribution unit that analyzes the telemetry information and the network operation information to evaluate the network load status and feeds the results back to the route control unit and the routing control unit to perform load distribution. Claim 2 A route label routing-based traffic distribution system for a low-orbit satellite network, wherein, in claim 1, the network operation information includes at least one of link status, orbit information, or visibility information, and the telemetry information includes at least one of transmission delay, packet loss rate, or queue occupancy. Claim 3 A path label routing-based traffic distribution system for a low-orbit satellite network according to claim 1, further comprising an exception handling unit that receives feedback information from the traffic distribution unit, and, in the event of a link disconnection or quality degradation, resets a local bypass path by referring to the feedback information and corrects the label information to maintain the continuity of data transmission. Claim 4 A route label routing-based traffic distribution system for a low-orbit satellite network according to claim 2, wherein the route control unit evaluates the availability of each link by referring to at least one of link status, orbit information, or visibility information, and calculates a route from a transmitting satellite to a destination satellite based on the evaluation result. Claim 5 A route label routing-based traffic distribution system for a low-orbit satellite network, wherein the route control unit encodes a label in either a short format or a long format according to the link characteristics of the calculated route, wherein the short format encodes four directions—up, down, left, and right—in 2-bit units, and the long format encodes eight directions including diagonal directions in 4-bit units, and includes a satellite number corresponding to each direction. Claim 6 A route label routing-based traffic distribution system for a low-orbit satellite network according to claim 1, wherein the routing control unit inserts label information input from the route control unit into a packet header, establishes a label-based route policy based on the label information, and transmits the data packet to a routing unit that routes the data packet and the data forwarding unit. Claim 7 A path label routing-based traffic distribution system for a low-orbit satellite network according to claim 1, wherein the data forwarding unit determines a transmission path for each hop unit under the control of the routing control unit and transmits telemetry information including at least one of a transmission delay, packet loss rate, or queue occupancy rate according to the transmission result to the traffic distribution unit. Claim 8 A route label routing-based traffic distribution system for a low-orbit satellite network according to claim 1, wherein the traffic distribution unit analyzes telemetry information from the data forwarding unit and network operation information from the satellite network unit to calculate a weight map per link, and feeds back the calculation result to the route control unit and the routing control unit. Claim 9 In claim 3, the exception handling unit, when a link disconnection or quality degradation is detected, resets a local bypass path by referring to weight information provided by the traffic distribution unit and modifies existing label information provided by the path control unit to ensure the continuity of data transmission, thereby forming a path label routing-based traffic distribution system for a low-orbit satellite network. Claim 10 A route label routing-based traffic distribution system for a low-orbit satellite network according to claim 1, wherein the traffic distribution unit dynamically updates link weights according to network load status and the updated weight information is reflected in the route calculation process of the route control unit. Claim 11 A method for distributing traffic based on a path label routing for a low-orbit satellite network, performed in a path label routing-based traffic distribution system for a low-orbit satellite network, comprising: (a) a process of collecting network operation information; (b) a process of calculating a path from a transmitting satellite to a destination satellite based on the network operation information and encoding the calculated path into label information; (c) a process of including the label information in a data packet and transmitting it; (d) a process of determining a transmission path for each hop unit by referring to the label information included in the data packet and collecting telemetry information while transmitting the data packet according to the determined path; and (e) a process of analyzing the collected telemetry information and the network operation information to evaluate the network load status and feeding the result back to the process (b). Claim 12 A route label routing-based traffic distribution method for a low-orbit satellite network, wherein, in claim 11, the network operation information includes at least one of link status, orbit information, or visibility information, and the telemetry information includes at least one of transmission delay, packet loss rate, or queue occupancy. Claim 13 A route label routing-based traffic distribution method for a low-orbit satellite network according to claim 11, further comprising the process of resetting a local bypass route by referring to feedback information obtained in process (e) and correcting the label information to maintain the continuity of data transmission when a link disconnection or quality degradation occurs. Claim 14 A route label routing-based traffic distribution method for a low-orbit satellite network, wherein the process of calculating a path in the above (b) process evaluates the availability of each link by referring to at least one of the link status, orbit information, or visibility information among the network operation information, and calculates a path from a transmitting satellite to a destination satellite based on the evaluation result. Claim 15 A route label routing-based traffic distribution method for a low-orbit satellite network, wherein the process of encoding a route in the above (b) process encodes a label in either a short format or a long format according to the link characteristics of the calculated route, wherein the short format encodes four directions—up, down, left, and right—in 2-bit units, and the long format encodes eight directions including diagonal directions in 4-bit units and includes a satellite number corresponding to each direction. Claim 16 A route label routing-based traffic distribution method for a low-orbit satellite network according to claim 11, wherein the data packet transmitted in the above process (c) includes a label header and a label body, wherein the label header records a type, a destination satellite ID, and a hop count, and the label body records movement direction information and a satellite number for each hop unit. Claim 17 A route label routing-based traffic distribution method for a low-orbit satellite network according to claim 11, wherein in the above process (d), telemetry information including at least one of transmission delay, packet loss rate, or queue occupancy rate for each home unit transmission result is collected, and said telemetry information is reflected in the network load evaluation of the above process (e). Claim 18 In claim 11, the above process (e) calculates a weight map per link by analyzing the telemetry information and the network operation information, and feeds the calculated weight information back to the above process (b) to reflect it in path calculation and label policy determination, a path label routing-based traffic distribution method for a low-orbit satellite network. Claim 19 In claim 13, the bypass path resetting process determines an alternative path on a local basis by referring to load weight information calculated in process (e) for a section where a link disconnection or quality degradation is detected, and modifies the label information to continue packet transmission, a path label routing-based traffic distribution method for a low-orbit satellite network. Claim 20 A route label routing-based traffic distribution method for a low-orbit satellite network, wherein the above process (e) is performed such that link weights are dynamically updated according to network load conditions and the updated weight information is reflected in the route calculation and label encoding processes of the above process (b).

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