Delay control system for improving network coding of bidirectional traffic

Abstract

The present invention relates to a delay control system for improving network coding of bidirectional traffic and, more specifically, to a delay control system for improving network coding of bidirectional traffic, which controls new network coding-aware routing that may set up a route by putting constraints on time in an IIoT network and efficiently use opportunities for network coding. The delay control system for improving network coding of bidirectional traffic comprises: an intermediate node request collection unit that receives a route request (PREQ) packet transmitted from a source node; an intermediate node calculation unit that calculates a deadline between the source node and a destination node on the basis of the route request (RREQ) packet received by the intermediate node request collection unit; and an intermediate node request transmission unit that transmits, on the basis of the deadline, the route request (RREQ) packet along an optimal route between the source node and the destination node.

Description

Delay control system for improving network coding of bidirectional traffic

[0001] The present invention relates to a delay control system for improving network coding of bidirectional traffic, and more particularly, to a delay control system for improving network coding of bidirectional traffic that controls a novel network coding-aware routing capable of setting a path by imposing time constraints and efficiently utilizing network coding opportunities in an Industrial Internet of Things (IIoT) network.

[0002] The Industrial Internet of Things (IIoT) refers to devices such as sensors and equipment that are interconnected through networks, including those in industrial sectors like manufacturing and energy management. This connectivity facilitates data collection, exchange, and analysis, and facilitates improvements in production and efficiency, as well as other economic benefits. In other words, the Industrial Internet of Things (IIoT) connects sensors and machines to the Internet in industrial environments to collect and analyze data. In multi-hop, large-scale IIoT environments, IIoT applications periodically generate and transmit more packets, such as sensor data, video surveillance data, and production control data, than in typical IoT environments. Therefore, IIoT applications place significant importance on transmission delays for operational accuracy and safety, requiring transmission paths that minimize delays.

[0003] However, if transmission paths are routed with a focus on delay and latency to meet the requirements of IIoT environments, this can significantly increase network interference and saturate available wireless resources. Therefore, most research on this technology has proposed network transmission techniques that utilize interference avoidance techniques such as Successive Interference Cancellation (SIC) or transmission schemes based on network coding. Successive Interference Cancellation (SIC) is a technique used by receivers in wireless data transmission to decode two or more packets that arrive simultaneously. SIC is achieved by the receiver first decoding the stronger signal, subtracting it from the combined signal, and then decoding the difference as the weaker signal. Furthermore, transmission schemes based on network coding offer opportunities for resource reuse, improving network throughput, and as wireless IIoT networks become denser and more widespread, these opportunities and performance gains increase.

[0004] However, conventional interference avoidance techniques tend to increase inefficient resource usage and increase computational complexity as the number of IIoT nodes increases. Furthermore, transmission systems based on network coding face several key challenges, including network coding-aware routing, packet encoding and decoding, signal synchronization, information caching, error correction, and resource allocation.

[0005] The present invention has been made in consideration of such problems, and the present invention provides a delay control system for enhancing network coding of bidirectional traffic by maximizing network coding gains based on a fully distributed path setting system that controls delay through NC-DSF (Network Coding-Aware Delayed Store and Forwarding), which is a low-complexity system that can be easily combined with passive or active network coding-aware routing systems, and controlling end-to-end path setting delay.

[0006] A delay control system for improving network coding of bidirectional traffic according to embodiments of the present invention is characterized by including: an intermediate node request collection unit that receives an RREQ (Route Request) packet transmitted from a source node; an intermediate node calculation unit that calculates a deadline between a source node and a destination node based on the RREQ (Route Request) packet received by the intermediate node request collection unit; and an intermediate node request transmission unit that transmits the RREQ (Route Request) packet along an optimal path between the source node and the destination node based on the deadline.

[0007] In embodiments of the present invention, the intermediate node request collection unit is characterized in that it collects the RREQ (Route Request) packet including bidirectional link state data between n source nodes and a destination node at the intermediate node.

[0008] In embodiments of the present invention, the intermediate node operation unit determines the deadline, which is an optimal delay time according to bidirectional link state data between n source nodes and a destination node included in the RREQ (Route Request) packet, and encodes necessary information from packets transmitted from n source nodes.

[0009] In embodiments of the present invention, the intermediate node operation unit is characterized by including a delay time determination unit that calculates an expected delay time based on bidirectional link state data between n source nodes and a destination node included in the RREQ (Route Request) packet, and determines the most optimal deadline among the expected delay times.

[0010] In embodiments of the present invention, the delay time determination unit applies a constant value that prevents packet paths from being concentrated on a specific node and alleviates the expected delay time according to the amount of algorithm data flow, thereby calculating the deadline using a mathematical formula.

[0011]

[0012] It is characterized by operating as . Here, B is the number of bidirectional data flows using the link, |B| is the total number of user nodes in the system, is the maximum end-to-end path setup delay, r is a constant value that mitigates the expected delay time, and f(r, B) represents the expected delay time for B.

[0013] In embodiments of the present invention, the delay time determination unit applies the shortest delay value that each node can process to control the delay of the RREQ (Route Request) packet at the relay node due to hardware and software limitations, and sets the deadline that alleviates the load weight of the node with the shortest transmission delay by a mathematical formula.

[0014]

[0015] It is characterized by operating as . Here, B(t) is the number of bidirectional data flows using the link in all instances t, is a two-way time function that varies depending on the degree of residual resources at all instances t, w is a control weight for load balancing, indicates a deadline.

[0016] In embodiments of the present invention, the above As the above B(t) increases, it controls the network load balancing and resource utilization degradation due to burst traffic on some node paths, and the mathematical expression

[0017]

[0018] It is characterized by being operated as . Here, w is a control weight for load balancing.

[0019] In embodiments of the present invention, the intermediate node operation unit is characterized in that it recognizes network coding of a fully distributed path setting system that controls delay based on flood-based NC-DSF (Network Coding-Award Delayed Store and Forwarding).

[0020] In embodiments of the present invention, the intermediate node operation unit is characterized in that it further includes a delay time flooding unit that applies (floods) the deadline to an adjacent node (two-hop).

[0021] In embodiments of the present invention, the intermediate node request transmission unit is characterized in that it transmits an RREQ packet encoded at an intermediate node to a destination node along a path with the shortest transmission delay based on the deadline, and transmits an RREP packet (Route Reply packet) corresponding to the encoded RREQ packet transmitted from the destination node to the source node.

[0022] According to the delay control system for improving network coding of bidirectional traffic as described above, the following effects are achieved.

[0023] First, the NC-DSF method, which considers all network traffic flows, can establish the maximum bidirectional path useful for network coding and maximize the bidirectional path.

[0024] Second, we can maximize network coding opportunities from performance results by calculating delays to maximize bidirectional network coding.

[0025] Third, the NC-DSF scheme can maximize network coding gain and control end-to-end path setup delay.

[0026] FIG. 1 is a configuration diagram of a delay control system for improving network coding of bidirectional traffic according to one embodiment of the present invention.

[0027] FIG. 2 is a configuration diagram illustrating an intermediate node operation unit of a delay control system for improving network coding of bidirectional traffic according to one embodiment of the present invention.

[0028] FIG. 3 is a schematic diagram illustrating a new flooding-based NC-DSF system model that takes into account a two-hop link state to increase network coding opportunities in a delay control system for improving network coding of bidirectional traffic according to one embodiment of the present invention.

[0029] Hereinafter, a delay control system for improving network coding of bidirectional traffic according to embodiments of the present invention will be described in detail with reference to the attached drawings. The present invention may be modified in various ways and may take various forms, and specific embodiments will be illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to a specific disclosed form, but should be understood to include all modifications, equivalents, and alternatives included in the spirit and technical scope of the present invention. In describing each drawing, similar reference numerals are used to indicate similar components. In the attached drawings, the dimensions of structures are illustrated in an enlarged form for clarity of the present invention or in a reduced form for a schematic understanding.

[0030] Furthermore, while terms such as "first" and "second" may be used to describe various components, these components should not be limited by these terms. These terms are used solely to distinguish one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the "second component," and similarly, the second component may also be referred to as the "first component." Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and shall not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0031]

[0032] The present invention is a technology that proposes a new network coding-aware routing control technique that can set a path by imposing a time constraint in an IIoT network and efficiently utilize opportunities for network coding.

[0033] FIG. 1 is a configuration diagram of a delay control system for improving network coding of bidirectional traffic according to one embodiment of the present invention.

[0034] Referring to Fig. 1, a delay control system for improving network coding of bidirectional traffic includes an intermediate node request collection unit (10), an intermediate node operation unit (20), and an intermediate node request transmission unit (30). The intermediate node request collection unit (10) receives an RREQ (Route Request) packet transmitted from a source node. That is, the intermediate node collects the RREQ (Route Request) packet including bidirectional link state data between n source nodes and a destination node, and the intermediate node operation unit (20) calculates a deadline between the source node and the destination node based on the RREQ (Route Request) packet received by the intermediate node request collection unit (10). Finally, the intermediate node request transmission unit (30) transmits the RREQ (Route Request) packet along an optimal path between the source node and the destination node based on the deadline. That is, to explain in more detail, the intermediate node request transmission unit (30) transmits the encoded RREQ packet from the intermediate node to the destination node along the path with the shortest transmission delay based on the deadline, and transmits the RREP packet (Route Reply packet) corresponding to the encoded RREQ packet transmitted from the destination node to the source node. Here, to explain the path with the shortest transmission delay in more detail, the encoded RREQ packet is transmitted to the next node after a delay set based on the deadline, and when routing through the encoded RREQ packet is completed, a path is set in which network coding can be maximized.

[0035] FIG. 2 is a configuration diagram illustrating an intermediate node operation unit of a delay control system for improving network coding of bidirectional traffic according to one embodiment of the present invention.

[0036] Referring to Fig. 2, the intermediate node operation unit (20) includes a delay time determination unit (20a) and a delay time overflow unit (20b). The intermediate node operation unit (20) determines the deadline, which is the optimal delay time according to the bidirectional link state data between the n source nodes and the destination node included in the RREQ (Route Request) packet, and encodes necessary information from the packets transmitted from the n source nodes.

[0037] Here, the delay time determination unit (20a) calculates the expected delay time based on the bidirectional link state data between the n source nodes and the destination node included in the RREQ (Route Request) packet, and determines the most optimal deadline among the expected delay times. That is, to explain in more detail, the delay time determination unit (20a) calculates the deadline using the following mathematical expression 1 by applying a constant value that prevents packet paths from being concentrated on a specific node and alleviates the expected delay time according to the amount of algorithmic data flow.

[0038]

[0039] Here, B is the number of bidirectional data flows using the link, |B| is the total number of user nodes in the system, is the maximum end-to-end path setup delay, r is a constant that mitigates the expected delay time, and f(r, B) is the expected delay time for B. As B increases, f(r, B) decreases significantly, and a fairly fast and accurate RREQ packet delay control is required at the relay node. Therefore, to solve this, the highest bidirectional constant was introduced. Therefore, the above Based on this, in order to control the delay of the RREQ (Route Request) packet at the relay node due to hardware and software limitations, the deadline that alleviates the load weight of the node with the shortest transmission delay is calculated by applying the shortest delay value that each node can process, and the deadline can be calculated as shown in the following mathematical expression 2.

[0040]

[0041] step, Here, |U| is the total number of user nodes in the system, is the maximum end-to-end path setup delay, r is a constant that mitigates the expected delay, B(t) is the number of bidirectional data flows using the link at every instance t, is a two-way time function that varies depending on the degree of residual resources at all instances t, w is a control weight for load balancing, indicates a deadline.

[0042] Also, the above , which controls network load balancing and resource utilization degradation due to burst traffic on some node paths as the above B(t) increases, and is a bidirectional variable calculated by the following mathematical expression 3.

[0043]

[0044] Here, w is a control weight for load balancing. In addition, the delay time flooding unit (20b) floods the deadline to adjacent nodes (two-hop).

[0045] FIG. 3 is a schematic diagram illustrating a new flooding-based NC-DSF system model that takes into account a two-hop link state to increase network coding opportunities in a delay control system for improving network coding of bidirectional traffic according to one embodiment of the present invention.

[0046] Referring to FIG. 3, the intermediate node operation unit (20) recognizes the network coding of a fully distributed routing scheme that controls delay based on the flood-based NC-DSF (Network Coding-Award Delayed Store and Forwarding). That is, to explain in more detail, the NC-DSF (Network Coding-Aware Delayed Store and Forwarding) is a fully distributed routing scheme that controls delay. As a low-complexity system that can be easily combined with existing passive or active network coding-aware routing schemes, the NC-DSF scheme maximizes network coding gain and controls end-to-end routing delay. Considering all network traffic flows, the NC-DSF scheme establishes the maximum bidirectional path useful for network coding, and maximizing the bidirectional path means increasing the opportunity for network coding. The algorithm for generating bidirectional paths is a core part of the present patent, and first, like DSR (Dynamic Source Routing), it generates the received RREQCRoute. Before forwarding a REQUEST packet, it is delayed according to the above deadline. This deadline is a function that calculates the delay to maximize bidirectional network coding, thereby maximizing network coding opportunities in performance results. After the delay set by the delay function, the RREQ is transmitted to the next node, and once routing via the RREQ is completed, a path is established that maximizes network coding.

[0047] Accordingly, the present invention provides a delay control system for enhancing network coding of bidirectional traffic by maximizing network coding gain and controlling end-to-end path setup delay based on a fully distributed routing scheme that controls delay through NC-DSF (Network Coding-Aware Delayed Store and Forwarding), a low-complexity system that can be easily combined with passive or active network coding-aware routing schemes. According to the delay control system for enhancing network coding of bidirectional traffic as described above, the following effects are provided. First, the NC-DSF method, which considers all network traffic flows, can establish the maximum bidirectional path useful for network coding and maximize the bidirectional path. Second, the network coding opportunity can be maximized in the performance results from the function that calculates the delay for maximizing bidirectional network coding. Third, the NC-DSF scheme can maximize network coding gain and control end-to-end path setup delay.

[0048] Although the detailed description of the present invention described above has been described with reference to preferred embodiments of the present invention, it will be understood by those skilled in the art or having ordinary knowledge in the art that various modifications and changes can be made to the present invention without departing from the spirit and technical scope of the present invention as set forth in the claims to be described later.

Claims

1. Intermediate node request collection unit that receives RREQ (Route Request) packets transmitted from the source node; An intermediate node calculation unit that calculates a deadline between a source node and a destination node based on the RREQ (Route Request) packet received by the intermediate node request collection unit; An intermediate node request transmission unit that transmits the RREQ (Route Request) packet through an optimal route between the source node and the destination node based on the deadline; A delay control system for improving network coding of bidirectional traffic, characterized by including:

2. In paragraph 1, The above intermediate node request collection unit is, A delay control system for improving network coding of bidirectional traffic, characterized in that it collects RREQ (Route Request) packets containing bidirectional link state data between n source nodes and a destination node at an intermediate node.

3. In paragraph 1, The above intermediate node operation unit is, The deadline, which is the optimal delay time according to the bidirectional link state data between the n source nodes and the destination node included in the RREQ (Route Request) packet, is determined. A delay control system for improving network coding of bidirectional traffic, characterized by encoding necessary information from packets transmitted from n source nodes.

4. In paragraph 1, The above intermediate node operation unit is, The expected delay time is calculated based on the bidirectional link state data between the n source nodes and the destination node included in the RREQ (Route Request) packet, A delay control system for improving network coding of bidirectional traffic, characterized by including a delay time determination unit for determining the most optimal deadline among the above expected delay times.

5. In paragraph 4, The above delay time determination unit, Prevent packet paths from being concentrated on specific nodes, By applying a constant value that alleviates the above expected delay time according to the amount of algorithmic data flow, the deadline is expressed as a mathematical formula. (B is the number of bidirectional data flows using the link, |U| is the total number of user nodes in the system, A delay control system for improving network coding of bidirectional traffic, characterized in that the delay control system is operated by (where r is the maximum end-to-end path setup delay, r is a constant value that alleviates the expected delay time, and f(r, B) is the expected delay time for B).

6. In paragraph 4, The above delay time determination unit, Due to hardware and software limitations, in order to control the delay of the RREQ (Route Request) packet at the relay node, the shortest delay value that each node can process is applied, and the deadline that alleviates the load weight of the node with the shortest transmission delay is expressed by a mathematical formula. (|U| is the total number of user nodes in the system, is the maximum end-to-end path setup delay, r is a constant that mitigates the expected delay, B(t) is the number of bidirectional data flows using the link at all instances t, is a bidirectional time function that varies with the degree of residual resources at all instances t, w is a control weight for load balancing, A delay control system for improving network coding of bidirectional traffic, characterized by operating on a deadline.

7. In paragraph 6, Above Is, As the above B(t) increases, the network load balancing and resource utilization degradation due to burst traffic on some node paths are controlled by the mathematical formula A delay control system for improving network coding of bidirectional traffic, characterized in that the delay control system is operated as (w is a control weight for load balancing).

8. In paragraph 4, The above intermediate node operation unit is, Based on the flood-based NC-DSF (Network Coding-Award Delayed Store and Forwarding), A delay control system for improving network coding of bidirectional traffic, characterized by recognizing network coding of a fully distributed routing scheme that controls delay.

9. In paragraph 4, The above intermediate node operation unit is, A delay flooding unit that floods the above deadline to adjacent nodes (two-hop); A delay control system for improving network coding of bidirectional traffic, characterized by further including:

10. In paragraph 1, The above intermediate node request transmission unit is, Based on the above deadline, the encoded RREQ packet is transmitted from the intermediate node to the destination node along the path with the shortest transmission delay. A delay control system for improving network coding of bidirectional traffic, characterized in that it transmits a RREP packet (Route Reply packet) corresponding to the encoded RREQ packet transmitted from the destination node to the source node.

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