A method for SD-WAN dynamic routing based on routing query

Abstract

The application relates to the technical field of routing query, and specifically discloses an SD-WAN dynamic routing method based on routing query, which comprises the following steps: S1: the maximum throughput and the actual throughput of each router are acquired, the residual throughput of the router is calculated, and the minimum value of the residual throughputs in the same link is taken as the path capacity of the link; S2: the link corresponding to the maximum value of the path capacity is taken as the main link, the remaining links are taken as auxiliary links, the byte number of this transmission is acquired, the minimum delay time is pre-set, the ideal byte number of the main link is calculated, whether the main link is congested is judged, and the initial allocation ratio is calculated; S3: the test information is transmitted along each auxiliary link, the propagation delay and the packet loss rate of each auxiliary link are acquired, the initial allocation ratio is corrected to obtain a corrected ratio, the transmission task of the auxiliary link is calculated, and transmission is performed. The application solves the problem of congestion under burst traffic by adjusting the transmission strategy.

Description

Technical Field

[0001] This invention relates to the field of routing query technology, and specifically to an SD-WAN dynamic routing method based on routing query. Background Technology

[0002] The core function of SD-WAN dynamic routing lies in intelligent path optimization. During actual network operation, it continuously monitors the network status comprehensively through various protocols. These protocols collect detailed information about each node and link in the network, including key indicators such as bandwidth utilization, latency, and packet loss rate. Based on this rich data, the dynamic routing mechanism uses complex algorithms for in-depth analysis and calculation, thereby automatically selecting the optimal path under the current network conditions.

[0003] However, in practical applications, main link congestion can occur. Due to the uncertainty of network traffic, under high load or sudden traffic surges, the main link may become congested because it reaches or exceeds its maximum throughput, affecting data transmission efficiency and stability. In traditional networks, traffic is often concentrated on the main link, and secondary link resources are not effectively utilized, leading to a decline in overall network performance. Faced with rapid changes in network conditions, traditional static configuration methods lack flexibility and cannot adjust transmission strategies in a timely manner to adapt to current needs. Summary of the Invention

[0004] The purpose of this invention is to provide a dynamic routing method for SD-WAN based on route lookup, thereby solving the above-mentioned technical problems.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A dynamic routing method for SD-WAN based on route lookup includes the following steps:

[0007] S1: Obtain the maximum throughput MT and actual throughput CT of each router in the same link. The maximum throughput MT represents the maximum data traffic processed by the router per unit time, and the actual throughput CT represents the data traffic processed by the router per unit time during actual operation.

[0008] Calculate the router's remaining throughput ST = MT - CT, and obtain the minimum remaining throughput ST for the same link. min Let the path capacity of this link be LT=ST. min ;

[0009] S2: Select the link with the maximum path capacity as the primary link, and the remaining links as secondary links. Obtain the number of bytes B transmitted in this transmission, preset the minimum delay time t, and calculate the ideal number of bytes ZB=LT for the primary link. main×t, where LT main This represents the path capacity corresponding to the main link;

[0010] If the number of bytes B ≥ 0.8ZB, it is recorded as primary link congestion. When primary link congestion exists, the initial allocation ratio BL is calculated based on the path capacity of each secondary link.

[0011] S3: Transmit the pre-set test information along each auxiliary link. The test information content is the same and the number of bytes is equal. Obtain the propagation delay Y and packet loss rate D of each auxiliary link at the end of the test information transmission. Correct the initial allocation ratio BL of the auxiliary links. Record the corrected initial allocation ratio as the correction ratio XL. Where λ1 represents the preset first coefficient and λ2 represents the preset second coefficient;

[0012] Compute the transmission task of the secondary link The primary link transmits 0.8 ZB of bytes, and the secondary link transmits bytes corresponding to transmission task R, where XL all This represents the sum of the correction ratios.

[0013] As a further aspect of the present invention: in step S1, if the remaining throughput ST≤0.2MT, it is recorded as a busy link, and the busy link does not participate in the selection of the subsequent main link and auxiliary link.

[0014] As a further aspect of the present invention: in step S1, if a routing loop exists between the main link and the auxiliary link, it is removed and not involved in subsequent operations.

[0015] As a further aspect of the present invention: in step S2, when there are links with equal path capacity, the link with fewer routers is designated as the main link.

[0016] As a further aspect of the present invention: in step S2, if the number of bytes B < 0.8ZB, it is considered that the main link is idle, and subsequent steps are stopped, and all data is transmitted through the main link.

[0017] As a further aspect of the present invention: in step S2, the method for calculating the initial allocation ratio BL based on the path capacity of each secondary link includes:

[0018] Get the total path capacity of all secondary links (LT) all The initial allocation ratio BL of the i-th secondary link i =LT i / LT all , among which, LT i This represents the path capacity of the i-th auxiliary link.

[0019] As a further aspect of the present invention: in step S3, the test information contains the same verification bit at both the beginning and the end. When the test information is received, if the contents of the verification bits at the beginning and the end are the same, the subsequent steps are executed; if they are different, the test information is resent.

[0020] As a further aspect of the present invention: in step S3, the auxiliary links with propagation delay Y > t are removed and do not participate in subsequent operations.

[0021] The beneficial effects of this invention are as follows: First, it is necessary to calculate the remaining throughput in the same link. It should be noted that although there are multiple routers on the same link, the final data transmission capacity of the link depends on the router with the smallest remaining throughput. Taking the minimum remaining throughput in the same link as the path capacity of the link can avoid the situation of exceeding its maximum throughput and causing congestion again. It should be noted here that the routers in the link do not only serve a single data transmission. Therefore, it is necessary to reserve some data transmission space for data transmission in other links.

[0022] Then, based on the calculated path capacity, the link with the maximum path capacity is selected as the primary link. Here, path capacity refers to the router's maximum throughput minus the actual throughput. Thus, we can conclude that the path capacity refers to the maximum data transmission capability that the current router can provide. The reason for selecting the link with the largest path capacity as the primary link is to reduce the use of secondary links for data transmission. Under the same conditions, the fewer links used for transmission, the lower the probability of errors during the entire transmission process. Sometimes, when the primary link is idle enough, it can independently handle the data transmission task, thus eliminating the need to rely on secondary links for transmission, thereby improving transmission efficiency and stability.

[0023] Next, a minimum delay time is set according to the specific delay requirements. The ideal number of bytes within this time period is calculated by multiplying the minimum delay time by the path capacity corresponding to the main link. When the number of bytes transmitted is greater than or equal to 80% of the ideal number of bytes, it is considered that the main link is congested. In this case, relying solely on the main link for transmission will lead to excessively high latency, so secondary links are needed for data transmission. However, data transmission using secondary links requires specifying the amount of data to be transmitted on each secondary link, which also needs to be controlled within a certain propagation delay. Therefore, test information needs to be set here, and the propagation delay and packet loss rate of each secondary link are obtained from the test information. Then, a correction ratio is calculated using a weighted formula, and the transmission task undertaken by each secondary link is calculated based on the proportion of the correction ratio. This invention solves the problem of congestion under sudden traffic surges by adjusting the transmission strategy. Attached Figure Description

[0024] The invention will now be further described with reference to the accompanying drawings.

[0025] Figure 1 This is a flowchart illustrating an SD-WAN dynamic routing method based on route lookup according to the present invention. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Please see Figure 1 As shown, this invention is an SD-WAN dynamic routing method based on route lookup, comprising the following steps:

[0028] S1: Obtain the maximum throughput MT and actual throughput CT of each router in the same link. The maximum throughput MT represents the maximum data traffic processed by the router per unit time, and the actual throughput CT represents the data traffic processed by the router per unit time during actual operation.

[0029] Calculate the router's remaining throughput ST = MT - CT, and obtain the minimum remaining throughput ST for the same link. min Let the path capacity of this link be LT=ST. min ;

[0030] S2: Select the link with the maximum path capacity as the primary link, and the remaining links as secondary links. Obtain the number of bytes B transmitted in this transmission, preset the minimum delay time t, and calculate the ideal number of bytes ZB=LT for the primary link. main ×t, where LT main This represents the path capacity corresponding to the main link;

[0031] If the number of bytes B ≥ 0.8ZB, it is recorded as primary link congestion. When primary link congestion exists, the initial allocation ratio BL is calculated based on the path capacity of each secondary link.

[0032] S3: Transmit the pre-set test information along each auxiliary link. The test information content is the same and the number of bytes is equal. Obtain the propagation delay Y and packet loss rate D of each auxiliary link at the end of the test information transmission. Correct the initial allocation ratio BL of the auxiliary links. Record the corrected initial allocation ratio as the correction ratio XL. Where λ1 represents the preset first coefficient and λ2 represents the preset second coefficient;

[0033] Compute the transmission task of the secondary link The primary link transmits 0.8 ZB of bytes, and the secondary link transmits bytes corresponding to transmission task R, where XL all This represents the sum of the correction ratios.

[0034] It's important to note that calculating the remaining throughput of a single link is crucial during network data transmission. In real-world network environments, multiple routers are often distributed along a link, collaborating to forward and transmit data. However, despite being on the same link, these routers may have varying data transmission capabilities and resource availability. Crucially, while multiple routers exist on the same link, the router with the lowest remaining throughput determines the link's ultimate data transmission capacity. This is because data transmission in a link, much like water flowing through a pipe, is limited by the individual nodes, i.e., the routers. If a router has low remaining throughput, even if other routers have significant transmission capacity, the overall data transmission speed will be constrained by this bottleneck. Based on this principle, the minimum remaining throughput of all routers on the same link is defined as the link's path capacity. This is significant because it effectively prevents congestion caused by exceeding the link's maximum throughput. When the amount of data transmitted exceeds the actual carrying capacity of the link, data will accumulate in the link and cannot be processed and forwarded in a timely manner, which will lead to network congestion and seriously affect network performance and data transmission efficiency.

[0035] It's important to note here that routers in a network link don't just serve a single, specific data transmission task. In actual network operation, these routers need to handle large amounts of data traffic simultaneously from different directions, sources, and destinations. They act like the dispatch center in a transportation hub, needing to allocate resources efficiently to ensure smooth data transmission in all directions.

[0036] Therefore, when calculating remaining throughput and determining path capacity, it is essential to reserve some space for data transmission in other links. This reserved space is like an emergency lane or buffer zone in a road, ensuring the stability and reliability of the entire network in case of emergencies or sudden increases in data traffic on other links.

[0037] After calculating the remaining throughput and determining the path capacity for the same link, the next step is to select a suitable primary link based on the path capacity. The path capacity mentioned here specifically refers to the router's maximum throughput minus its current actual throughput. This clearly shows the potential data transmission capacity that each router can provide under the current network conditions. Therefore, the path capacity accurately reflects the maximum data transmission capacity that the router can currently provide, comprehensively considering the router's own performance limits and the amount of data transmission tasks it is currently handling. One of the core purposes of selecting the link with the largest path capacity as the primary link is to minimize the use of secondary links for data transmission. In complex network environments, each link and router carries certain risks and uncertainties. When data needs to be transmitted through multiple links, the probability of problems increases accordingly. Different links may have different transmission delays, potentially leading to disordered packet arrival; or a router on a secondary link may suddenly fail, all of which will affect the smooth progress of the entire data transmission.

[0038] However, in practical applications, sometimes when the main link is sufficiently idle, it is fully capable of independently handling data transmission. In such cases, rationally allocating all data transmission to the main link can avoid using secondary links, thereby significantly improving transmission efficiency and stability. Overall, allowing the main link to fully utilize its function when idle not only makes full use of network resources but also reduces various problems that may be caused by multi-link transmission, ensuring that data can reach its destination quickly and stably.

[0039] After selecting the primary link, the next step is to set the minimum latency time based on specific latency requirements. This step directly affects the real-time performance and efficiency of data transmission. The minimum latency time is the result of a comprehensive consideration of business needs and network performance; it represents the shortest time required for data to be transmitted from the source to the destination under ideal conditions.

[0040] Once the minimum latency is determined, the ideal number of bytes within that timeframe can be calculated by multiplying this timeframe by the path capacity of the main link. This ideal number of bytes essentially refers to the maximum amount of data the main link can theoretically transmit without blocking within the minimum latency, providing an important reference indicator to measure whether the current transmission task is approaching or exceeding the main link's capacity. When the number of bytes transmitted is greater than or equal to 80% of the ideal number of bytes, we consider the main link to be congested. This is because in a real network environment, if the main link is overloaded, its transmission latency will increase significantly, potentially leading to packet loss or retransmission, severely impacting transmission efficiency and stability. Therefore, in such cases, relying solely on the main link for transmission is clearly unwise; auxiliary links are needed to share the transmission load and alleviate the pressure on the main link.

[0041] However, data transmission via secondary links is not simply a matter of evenly distributing data across them. Different secondary links may exhibit varying performance, including propagation delay and packet loss rate. To ensure efficient and stable data transmission, the amount of data transmitted on each secondary link needs to be reasonably defined. This also requires control within a certain propagation delay range to avoid impacting overall transmission performance due to excessive latency on the secondary links. To allocate transmission tasks to the secondary links, test information needs to be established. This test information can consist of specific data packets or streams sent to each secondary link, recording key metrics such as propagation delay and packet loss rate during transmission. By collecting this test information, a comprehensive understanding of the performance status of each secondary link can be obtained.

[0042] Then, we can calculate the correction ratio using a weighted formula. This correction ratio is calculated based on a combination of indicators such as the propagation delay and packet loss rate of the secondary link, reflecting the actual transmission capacity of the secondary link under the current network conditions. The higher the correction ratio, the more transmission tasks the secondary link undertakes; conversely, the lower the correction ratio, the less transmission tasks it undertakes.

[0043] Finally, the transmission task undertaken by each auxiliary link is calculated based on the proportion of the correction ratio. In this way, we can dynamically adjust the transmission task allocation of each auxiliary link according to the actual network conditions to ensure data transmission efficiency and stability. This invention, through this flexible transmission strategy adjustment, effectively solves the problem of congestion under sudden traffic surges, improving the overall network performance and reliability.

[0044] In another preferred embodiment of the present invention, if the remaining throughput ST≤0.2MT, it is recorded as a busy link, and the busy link does not participate in the selection of subsequent main links and auxiliary links.

[0045] It's worth noting that before entering the primary link selection process, all links need to be screened first. This step simplifies the subsequent selection of primary and secondary links, focusing on the remaining throughput of each link. Remaining throughput, a key indicator of a link's current available transmission capacity, directly reflects its potential to handle data transmission tasks in the current network environment. When a link's remaining throughput is less than 20% of its maximum throughput, it means the link is already highly congested, with limited available transmission resources. In this case, even if it's included in the subsequent primary or secondary link selection, it's highly likely that insufficient capacity will lead to data transmission congestion, delays, or even data loss, thus affecting the overall stability and reliability of data transmission.

[0046] To simplify operations and reduce unnecessary computational and judgment complexity during the subsequent selection of primary and secondary links, thereby improving link selection efficiency, the actual carrying capacity of the links cannot be ignored to ensure data transmission stability. Therefore, busy links with less than 20% remaining throughput are marked as busy links and removed from the subsequent primary and secondary link selection lists. This pre-screening mechanism ensures that the selected links have relatively sufficient transmission capacity, building a stable and efficient data transmission channel that allows data to flow smoothly within the network.

[0047] In another preferred embodiment of the present invention, if a routing loop exists between the main link and the auxiliary link, it is removed and does not participate in subsequent operations.

[0048] Understandably, if a routing loop exists within the set of main and auxiliary links, to ensure the efficiency of data transmission across the entire network, the link with the routing loop will be removed and excluded from any subsequent operations. The existence of a routing loop causes data to continuously circulate within the loop once it enters, failing to reach its destination. This not only wastes network resources significantly, resulting in meaningless bandwidth occupation and affecting other normal data transmission tasks, causing lag or even interruptions, but also infinitely increases data transmission latency, severely violating our requirements for real-time and efficient data transmission.

[0049] In another preferred embodiment of the present invention, when there are links with equal path capacity, the link with fewer routers is designated as the main link.

[0050] It's important to note that in complex network environments, path capacity is a crucial indicator of link transmission capability. When multiple links have the same path capacity, other factors need to be considered to make a better choice. Routers, as key nodes in the network, have a multifaceted impact on data transmission. Links with fewer routers mean that data needs to pass through fewer forwarding nodes during transmission, reducing processing latency during packet forwarding, improving real-time data transmission, and enabling data to reach its destination more quickly.

[0051] On the other hand, fewer routers also mean lower transmission complexity and higher stability. Each time a data packet passes through a router, it undergoes a series of processing operations, such as route lookup and queue management. These operations not only consume time but can also lead to packet loss or transmission errors due to router overload or other malfunctions. Therefore, choosing a link with fewer routers as the main link can effectively reduce these potential risks, minimize problems that may occur during data transmission, and improve the reliability and stability of the entire network.

[0052] In another preferred embodiment of the present invention, if the number of bytes B < 0.8ZB, the main link is considered idle, subsequent steps are stopped, and all data is transmitted through the main link.

[0053] It should be noted that if the number of bytes B to be transmitted is found to be less than 0.8 times the ideal number of bytes ZB, then since the remaining transmission capacity of the main link is sufficient to easily handle the current data transmission task, and there is no need to use an auxiliary link to share the transmission pressure, all data will be transmitted through the main link to simplify the transmission process, improve transmission efficiency, and reduce unnecessary resource consumption. As a path with strong transmission capacity and relatively stable performance in the network, the main link can complete data transmission tasks with higher efficiency and lower latency when idle.

[0054] In another preferred embodiment of the present invention, the method for calculating the initial allocation ratio BL based on the path capacity of each secondary link includes:

[0055] Get the total path capacity of all secondary links (LT) all The initial allocation ratio BL of the i-th secondary link i =LT i / LT all , among which, LT i This represents the path capacity of the i-th auxiliary link.

[0056] In another preferred embodiment of the present invention, the test information includes a segment of the same verification bit at the beginning and the end. When the test information is received, if the contents of the verification bits at the beginning and the end are the same, the subsequent steps are executed; if they are different, the test information is resent.

[0057] It is worth noting that the test information includes a unique and verifiable verification bit at both the beginning and end, ensuring the integrity and accuracy of the test information during transmission. When the receiving end successfully receives the test information, it immediately compares the verification bits in the beginning and end. If the verification bits in the beginning and end are identical, it indicates that the test information has not been tampered with, lost, or damaged during transmission, and its content retains its original integrity and accuracy. At this point, subsequent steps can be performed.

[0058] However, if the verification bits at the beginning and end of the test information differ during the comparison process, it means that some anomaly may have occurred during transmission, resulting in modification or partial loss of the information. To obtain accurate and reliable test results, this potentially problematic test information cannot be used directly for subsequent operations; instead, it needs to be resent. The purpose of resending the test information is to obtain a complete and accurate set of test data again, ensuring that subsequent steps can proceed smoothly based on correct data, thereby guaranteeing the effectiveness of the entire testing process.

[0059] In another preferred embodiment of the present invention, the secondary links with propagation delay Y > t are removed and do not participate in subsequent operations.

[0060] It is worth noting that when the propagation delay Y of a secondary link exceeds the preset minimum delay time t during network data transmission, it indicates that using this secondary link for data transmission has a high probability of causing data packet delays during transmission. Once this delay occurs, data will accumulate on the transmission path, leading to a significant increase in the overall system latency.

[0061] In network systems, increased latency can severely negatively impact data real-time performance, system response speed, and user experience. To avoid these adverse consequences caused by using secondary links with excessive propagation delays, and to ensure the entire network system maintains efficient and stable operation, secondary links with propagation delays exceeding the preset minimum latency time are eliminated. This approach prevents potential latency risks from these secondary links at the source, ensuring data transmission through the remaining high-quality links, thereby maintaining the low-latency characteristics of the entire network system and ensuring the smooth operation of various network applications.

[0062] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. A method for SD-WAN dynamic routing based on routing query, characterized in that, The method comprises the following steps: S1: obtaining the maximum throughput MT and the actual throughput CT of each router in the same link, wherein the maximum throughput MT represents the maximum data flow processed by the router per unit time, and the actual throughput CT represents the data flow processed by the router per unit time in actual operation; The remaining throughput ST of the computing router is calculated as MT-CT, and the minimum value ST of the remaining throughput in the same link is obtained min The path capacity LT of the link is set as ST min ; S2: select the link corresponding to the maximum path capacity as the main link, the remaining links as auxiliary links, obtain the number of bytes B of this transmission, pre-set the minimum delay time t and calculate the ideal number of bytes ZB=LT main of the main link, wherein LT main represents the path capacity corresponding to the main link; If the byte quantity B is greater than or equal to 0.8ZB, the main link is crowded, and the initial allocation ratio BL is calculated based on the path capacity of each auxiliary link when the main link is crowded. S3: transmitting pre-set test information along each auxiliary link, the test information having the same content and equal byte number, obtaining the propagation delay Y and the packet loss rate D of each auxiliary link at the end of test information transmission, modifying the initial allocation proportion BL of the auxiliary link, taking the modified initial allocation proportion as the modified proportion XL, and the modified proportion XL wherein λ1 represents a pre-set first coefficient and λ2 represents a pre-set second coefficient. Computing transmission tasks for a secondary link , let the primary link transmit 0.8ZB bytes, and the secondary link transmit the bytes corresponding to the transmission task R, where XL all represents the sum of the correction ratios.

2. The method of claim 1, wherein, In the step S1, if the residual throughput ST is less than or equal to 0.2MT, the link is busy, and the busy link does not participate in the selection of the main link and the auxiliary link in the subsequent steps. 3.The SD-WAN dynamic routing method based on routing query of claim 1, wherein, In the step S2, if there is a routing loop in the main link and the auxiliary link, the routing loop is removed and does not participate in the subsequent operation.

4. The method of claim 1, wherein, In the step S2, when there are links with equal path capacities, the link with fewer routers is recorded as the main link.

5. The method of claim 1, wherein, In the step S2, if the byte quantity B is less than 0.8ZB, the main link is idle, the subsequent steps are stopped, and all data is transmitted through the main link.

6. The method of claim 1, wherein, In the step S2, the method for calculating the initial allocation ratio BL based on the path capacity of each auxiliary link comprises: LT = LT + LT + LT + LT + LT + LT + LT + LT + LT + LT all BL = BL + BL + BL + BL + BL + BL + BL + BL + BL + BL i = LT i / LT all , where LT i represents the path capacity of the i-th secondary link.

7. The method of claim 1, wherein, In the step S3, the test information comprises a same verification bit in the head and the tail, when the test information is received, if the contents of the verification bits in the head and the tail are the same, the subsequent steps are executed, and if the contents are different, the test information is re-sent. 8.The method of claim 1, wherein, In the step S3, the auxiliary link with the propagation delay Y greater than t is removed and does not participate in the subsequent operation.

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