KR101704822B1 - Apparatus and method for routing based on cross-layer - Google Patents

Abstract

A cross layer based routing method and apparatus are provided. The routing method may adaptively determine the transmission period of the probe packet based on the flow of the data traffic, and may determine whether to retransmit the failed packet using the flow of data traffic and the turning point (TP). Then, the link quality can be predicted using the link cost and the traffic weight calculated based on the flow of the data traffic, and the parent node can be determined based on the predicted link quality.

Description

[0001] APPARATUS AND METHOD FOR ROUTING BASED ON CROSS-LAYER [0002]

The present invention relates to a routing technique that improves reliability and energy efficiency for real-time applications in sensor networks.

A real-time application service such as a defense surveillance boundary is an application that copes with large-scale soldiers, and can be composed of a large number of sensor nodes. At this time, real-time data transfer between sensor nodes is required. These real-time applications require 100% packet transmission success rate considering real-time transmission of data packets and energy efficiency. At this time, a lot of network overhead occurs due to data transmission control, and there is a difficulty in aiming at a real-time transmission success rate of 100% due to such load.

In addition, real-time applications should transmit the important information, such as the target, which should be important, to the remote command center quickly in real time. Furthermore, the energy consumption of the nodes should be minimized to maximize the lifetime of the network.

In order to guarantee real-time transmission of applications, there is a need for a routing technology capable of maintaining high reliability and energy efficiency so as to ensure a delay time. To this end, it is necessary to reserve bandwidth in advance, such as QoS (Quality of Service), or to calculate a delay time for each node and maintain the guarantee time for each connection (data flow). However, due to the trade-off between QoS and energy efficiency, there is a difficulty in realizing high-reliability routing that can maintain energy efficiency.

Therefore, in order to increase the success rate of transmission and reception of important data at the end-to-end in real-time transmission of important data, a routing technology capable of improving energy efficiency while having high reliability is needed.

The present invention provides a routing method and apparatus capable of improving energy efficiency while achieving high reliability in order to increase the success rate of transmission and reception of important data in end-to-end data transmission in real time.

In addition, a routing method and apparatus are provided that can simplify the procedure of performing cross layers based on each layer.

The present invention also provides a routing method and apparatus capable of adaptively selecting a path according to a flow of data traffic generated in a network and transmitting data and control packets.

A routing method according to an exemplary embodiment of the present invention includes adaptively determining a transmission period of a probe packet based on a flow of data traffic, transmitting the data traffic using a turning point (TP) Determining whether a failed packet is retransmitted, estimating a link quality using a link cost calculated based on the flow of the data traffic and a traffic weight, And determining a parent node based on the parent node.

In addition, the step of adaptively determining the transmission period of the probe packet may include: setting a transmission period of a probe packet as a threshold value through initialization of a network, the probe packet including a meter reading Transmitting a probe packet to a neighbor node according to a transmission period of the probe packet set to the threshold value and calculating a transmission period of a new probe packet based on the flow of the data traffic according to the transmission of the probe packet Step < / RTI >

The step of adaptively determining the transmission period of the probe packet may include resetting the transmission period of the probe packet to a transmission period of the new probe packet when the transmission period of the new probe packet is greater than the threshold, And transmitting the probe packet to the neighbor node according to a transmission period of the reconfigured probe packet.

The determining whether to retransmit the data packet may include determining to retransmit the packet that failed transmission if the flow of the data traffic is greater than the switch point, if the flow of data traffic is less than the switch point Determining to not retransmit the packet that failed to transmit, and transmitting at least one of the packets and data packets that failed to transmit based on the retransmission determination to a neighboring node.

The determining of the parent node may include receiving routing information from neighboring nodes, determining a current parent node and one or more candidate parent nodes based on the hop count included in the received routing information, As a node.

The selecting of the parent node may further include comparing the link quality of the current parent node with the link quality of the candidate parent node, comparing the link quality of the current parent node with the link quality of the current parent node, Comparing the hop count of the current parent node and the hop count of the candidate parent node if the link quality of the candidate parent node is within a predetermined reference level, comparing the hop count of the current parent node with the hop count of the candidate parent node, As a node.

A routing apparatus according to an embodiment of the present invention includes a period determination unit that determines a transmission period of a probe packet based on a flow of data traffic, a period determination unit that determines a transmission period of the probe packet based on the data traffic flow and a turning point A link quality predicting unit for predicting a link quality using a link cost and a traffic weight calculated on the basis of the flow of the data traffic, And a routing unit that provides routing through the determined parent node based on the determined link quality.
Wherein the period determining unit includes: a period setting unit configured to set a transmission period of a probe packet as a threshold value through network initialization; And a transmission controller for transmitting a probe packet to a neighbor node according to a transmission period of the probe packet set to the threshold value.
Wherein the period determining unit further includes a period calculating unit that calculates a transmission period of a new probe packet based on a flow of data traffic according to the transmission of the probe packet,
The transmission control unit transmits the probe packet to the neighbor node according to any one of a transmission period of the calculated new probe packet and a transmission period of the set probe packet.
Wherein the period setting unit resets the transmission period of the probe packet to a transmission period of the new probe packet if the transmission period of the new probe packet is greater than the threshold value, And transmits the data packet to the neighboring node according to the data packet.
Wherein the retransmission determining unit determines to retransmit the packet that failed the transmission if the flow of the data traffic is greater than the switching point and does not retransmit the packet that failed the transmission if the flow of the data traffic is smaller than the switching point .
And the retransmission determination unit transmits at least one of the packet and the data packet failed in the transmission to the neighboring node based on the retransmission determination.
The routing unit determines either the current parent node or one or more candidate parent nodes as the parent node based on the hop count included in the routing information received from the neighboring nodes.
Wherein the routing unit comprises: a link quality comparing unit comparing a link quality of the current parent node with a link quality of the candidate parent node; A hop count comparing unit comparing the hop counts of candidate parent nodes having similar link quality through the link quality comparison; And a parent node determining unit determining the node having the shortest hop count as the parent node through the hop count comparison.
The hop count comparison unit determines whether there are candidate parent nodes having similar link quality among candidate parent nodes having better link quality than the current parent node and the hop count comparison unit determines that similar candidate parent nodes exist And then compares the hop counts of the similar candidate parent nodes.
The routing unit provides cross-layer-based routing through the determined parent node.

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According to the present invention, it is possible to improve the energy efficiency in a node or a network by transmitting a data packet according to the transmission period of the adjusted probe packet based on the flow of the data traffic.

In addition, by providing the routing through the selected parent node using the link quality and the hop count, it is possible to provide a routing which increases the reliability while guaranteeing the delay time.

In addition, by providing cross-layer-based routing, it is possible to simplify the procedure of execution between layers.

FIG. 1 is a diagram for explaining a routing method according to an embodiment of the present invention. Referring to FIG.
2 is a diagram illustrating a layer configuration for providing a routing method according to an embodiment of the present invention.
FIG. 3 is a flowchart illustrating a configuration for adaptively determining a transmission period of a probe packet according to an embodiment of the present invention. Referring to FIG.
4 is a flowchart illustrating a configuration for determining whether to retransmit a link level according to an embodiment of the present invention.
5 is a diagram illustrating a success rate for a packet generation interval for retransmission determination according to an embodiment of the present invention.
6 is a diagram illustrating an end-to-end delay for a packet generation interval for retransmission determination according to an embodiment of the present invention.
7 is a flowchart provided to illustrate a configuration for predicting link quality according to an embodiment of the present invention.
8 is a flowchart illustrating a configuration for determining a parent node according to an embodiment of the present invention.
9 is a block diagram illustrating a detailed configuration of a routing apparatus according to an embodiment of the present invention.
10 is a block diagram showing a detailed configuration of the period determining unit of FIG. 9 according to an embodiment of the present invention.
11 is a block diagram showing a detailed configuration of the link quality predicting unit of FIG. 9 according to an embodiment of the present invention.
12 is a block diagram showing a detailed configuration of the routing unit of FIG. 9 according to an embodiment of the present invention.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to or limited by the embodiments. In addition, the same reference numerals shown in the drawings denote the same members.

FIG. 1 is a diagram for explaining a routing method according to an embodiment of the present invention. Referring to FIG.

First, in step 110, the routing device may determine a probe interval (PI) of a probe packet. Here, the probe packet is a probe packet for predicting the link quality, and a hello packet or the like can be used. At this time, a sensor node may be used as a routing device.

For example, the routing device may set the transmission period of the probe packet to a threshold value through network initialization. Here, the threshold value may be preset within a range that does not lead to an image overhead of the network. Then, the routing device can check the flow of data traffic for a predetermined reference time, and adaptively adjust the transmission period of the probe packet according to the flow of the checked data traffic. A detailed description of adaptive adjustment of the transmission period of the probe packet will be given later with reference to FIG.

Then, in step 120, the routing device may determine whether to retransmit the link level. At this time, the routing device can determine whether to retransmit the packet that failed to transmit using the flow of data traffic and the turning point (TP).

For example, a routing device may control the retransmission of a packet that failed to transmit and the transmission of a data packet, by designing a cross layer for energy efficiency and reduction of inter-layer load.

In step 130, the routing device can estimate the link quality using the link cost and the traffic weight.

Then, in step 140, the routing device may determine the parent node based on the link quality and the hop count of the candidate parent nodes.

Then, in step 150, the routing device may provide routing through the determined parent node.

2 is a diagram illustrating a layer configuration for providing a routing method according to an embodiment of the present invention.

2, an application layer 210, a network layer 220, a MAC layer 230, and an RF module 240 may cooperate to provide a routing method according to an exemplary embodiment of the present invention.

The application layer 210 may generate data packets and generate sensing data or node middleware packets.

The network layer 220 may perform and control key functions for routing. For example, the network layer 220 can control the transmission of the probe packet by adaptively adjusting the transmission period of the probe packet by grasping the flow of the data traffic. The network layer 220 may then determine whether to retransmit the failed packet based on the flow of data traffic. The network layer 220 may then determine the parent node and manage the routing table.

The MAC layer 230 can control retransmission of a packet that failed in transmission and transmission of a data packet according to retransmission determined in the network layer. At this time, the RF module 240 can substantially transmit the data packet based on the control of the MAC layer 230, and retransmit the packet that failed to transmit. Then, the MAC layer 230 can receive an ACK for the transmitted data packet.

FIG. 3 is a flowchart illustrating a configuration for adaptively determining a transmission period of a probe packet according to an embodiment of the present invention. Referring to FIG.

First, in step 310, the routing device may set the transmission period (PI) of the probe packet to a threshold value through network initialization. At this time, a hello packet can be used as a probe packet for accurate prediction of link quality.

In step 320, the routing device may transmit the probe packet to the neighboring nodes according to the PI set as the threshold value.

In step 330, a new probe packet period (new PI) may be calculated using Exponential Weighted Moving Average (EWMA).

 At this time, the routing device can calculate the transmission period of the probe packet generated during network operation or transmitted to the network.

For example, the routing device checks the transmission of the probe packet transmitted during a predetermined reference time, determines the flow of data traffic, and increases or decreases the PI using EWMA according to the frequency of the flow of data traffic. Can be calculated.

More specifically, when the flow of data traffic is high, the routing apparatus can reduce the PI set to the threshold value and calculate the reduced PI with the new PI. That is, when there are a large number of probe packets transmitted during a preset reference time, the routing device may reduce the transmission period of the probe packet set to the threshold value and calculate the transmission period of the reduced probe packet as a new PI.

At this time, if the flow of data traffic is low, the routing apparatus can increase the PI set as the threshold value and calculate the increased PI as a new PI. That is, when a probe packet transmitted during a preset reference time is rare, the routing device may increase the transmission period of the probe packet set to the threshold value and calculate the transmission period of the increased probe packet as a new PI.

Then, in step 340, the routing device can reset the PI by comparing the new PI with a threshold value.

More specifically, if the new PI is greater than the threshold (340: YES), the routing device may reset the new PI to PI. In other words, the routing device can update the PI set to the threshold to the new PI calculated in step 330. [ Then, in step 360, the routing device may transmit the probe packet to the neighboring nodes according to the reset PI.

At this time, if the new PI is less than or equal to the threshold value (340: NO), in step 370, the routing device can transmit the probe packet to neighboring nodes according to the previously set PI. Here, the previously set PI may be the PI set as the threshold value, or the PI set as the new PI.

Generally, in predicting the link quality using a probe packet, if the link quality is predicted for a long term, continuous packet loss may occur for a link with bad link quality. On the other hand, when link quality is predicted during a short term, packet loss and energy consumption may occur because the routing path is changed according to the parent node selection. Accordingly, as shown in FIG. 3, the routing apparatus according to an embodiment of the present invention adaptively adjusts the transmission period (PI) of the probe packet based on the flow of data traffic, and transmits the probe packet according to the adjusted PI The frequency can be adjusted. This can reduce energy consumption and packet loss due to frequent transmission of probe packets.

4 is a flowchart illustrating a configuration for determining whether to retransmit a link level according to an embodiment of the present invention.

Referring to FIG. 4, first, a routing device may receive data packets from neighboring nodes. The routing device may then forward the received data packet to the application layer if the received data packet is a local data packet.

Then, in step 410, the routing apparatus can calculate the generation interval of the data packet using the EWMA.

At this time, the routing apparatus can set a turning point (TP) based on the routing success rate for the packet generation interval. Here, the switching point indicates a point where the routing success rate is reversed with respect to the packet generation interval as shown in FIG. In addition, the routing apparatus may set a turning point (TP) based on the end-to-end delay for the packet generation interval, and may use the routing success rate for the packet generation interval and the end- .

More specifically, if retransmission of a packet that has failed in transmission is frequent, data transmission delay and energy consumption may increase. Accordingly, the routing apparatus sets the TP according to the flow of the data traffic, and can determine whether to retransmit the packet that failed to transmit using the TP. At this time, the routing apparatus can set the TP based on at least one of the routing success rate for the packet generation interval and the end-to-end delay for the packet generation interval.

For example, referring to FIG. 5, when the packet generation interval (32, 16, 8, 4, 2, 1 second) is about 3 seconds or more, a protocol for performing retransmission (Reliable_Route) On the other hand, the shortest routing protocol (Mint_Route, Standard) shows that the success rate decreases. At this time, if the packet generation interval is less than about 3 seconds, it can be confirmed that the success rate of the shortest distance routing protocol is higher.

Referring to FIG. 6, in the case of the protocol (Surage_Reliable) for performing retransmission, it is confirmed that the end-to-end delay is twice as long as that in the case of less than 3 seconds have. Thus, according to FIGS. 5 and 6, since there is a switching point TP of about 3 seconds, the routing device can set the TP to 3 seconds and determine whether to retransmit based on the flow of data traffic or TP set.

In step 420, if the interval of generating the data packet is greater than TP, the routing apparatus can determine to retransmit the packet that failed in transmission. Then, in step 440, the routing device may retransmit the failed transmission packet to the neighboring nodes and transmit the data packet to the neighboring nodes. Here, the data packet is sensing data such as temperature information and position information.

If it is determined in step 420 that the interval of generating the data packet is equal to or less than TP, the routing apparatus can determine not to retransmit the failed packet in step 440. Then, in step 460, the routing device may transmit the data packet to neighboring nodes. In other words, the routing device can only transmit data packets without retransmission of packets that failed to transmit.

Referring to FIG. 4, the routing apparatus can directly transmit a retransmission command for retransmission of a packet that failed in the network layer 220 to the MAC layer 230 using a function call. In other words, a routing device can provide cross-layer-based routing to use function calls without using inter-layer protocol interfaces at the network layer. As described above, the routing apparatus directly transmits the retransmission command from the network layer to the MAC layer, thereby reducing the control load between layers in the node, thereby enhancing the energy efficiency.

7 is a flowchart provided to illustrate a configuration for predicting link quality according to an embodiment of the present invention.

First, in step 710, the routing device may determine one or more candidate nodes among a plurality of neighbor nodes.

Then, in step 720, the routing device may obtain the Tx Link cost, and the received link cost.

In one example, the routing device can weight transmit link costs by weighting the data traffic in the transmit direction. Then, the routing apparatus can acquire the received link cost by extracting the received link cost from the routing information received from the candidate parent nodes.

At this time, in step 730, the routing apparatus can calculate transmission traffic weight values and reception traffic weight values using EWMA, respectively.

For example, if the previously acquired transmit / receive link cost is more important than the current transmit / receive link cost, the routing device may weight the previously obtained transmit / receive link cost using EWMA. Similarly, if the current transmit / receive link cost is more important than the previously obtained transmit / receive link cost, the routing device may weight the current transmit / receive link cost using EWMA.

Then, in step 740, the routing device can predict the link quality of the candidate parent nodes based on the traffic weight and the link cost.

At this time, if there is a candidate parent node having the same predicted link quality, the routing apparatus can estimate the link quality by adding a weight according to a characteristic of transmitting the data packet among the candidate parent nodes. In other words, the link quality of the candidate parent node can be predicted by weighting the node having the characteristic of transmitting the data packet among the candidate parent nodes. Accordingly, the routing apparatus can adapt to the environment in the actual sensor network and extract the parent node. This increases the transmission / reception success rate of the data packet, which is advantageous in transmitting the data in real time.

8 is a flowchart illustrating a configuration for determining a parent node according to an embodiment of the present invention. In FIG. 8, considering the situation that the shortest distance routing path is higher than the TP, the routing apparatus can determine the parent node as a parent node using the hop count among the neighbor nodes having the same level of link quality.

More specifically, in step 810, the routing device may update the routing table based on the routing information received from the neighboring nodes. At this time, the routing information may include a hop count.

In step 820, the routing device may compare the link quality of the candidate parent node with the link quality of the current parent node, respectively.

In this case, if the link quality of the candidate parent node is greater than the link quality of the current parent node, the routing apparatus can check whether there is a candidate parent node having similar link quality among the candidate parent nodes in step 830.

For example, the routing device may select a candidate parent node among the candidate parent nodes whose link quality is better than the current parent node. At this time, when the difference value between the link qualities of the selected candidate parent nodes is included in the predetermined reference range, the routing apparatus can determine that the link qualities of the selected candidate parent nodes are similar.

Then, in step 840, the routing device may determine the parent node using the hop count of candidate parent nodes with similar link quality.

For example, the routing device may determine a node having the smallest hop count among the candidate parent nodes having similar link quality as the parent node.

Next, in step 850, the routing device may provide routing through the determined parent node.

9 is a block diagram illustrating a detailed configuration of a routing apparatus according to an embodiment of the present invention.

9, the routing apparatus 900 may include a period determination unit 910, a retransmission determination unit 920, a link quality estimation unit 930, a routing unit 940, and a routing table 950 .

The period determining unit 910 can adaptively determine the transmission period (PI) of the probe packet based on the flow of the data traffic. Referring to FIG. 10, the period determining unit 910 may include a period setting unit 911, a transmission control unit 912, and a period calculating unit 913.

For example, the period setting unit 911 may set the PI to a preset threshold value through network initialization. Then, the transmission control unit 912 can transmit the probe packet to the neighbor nodes according to the PI set as the threshold value. Next, the period calculator 913 may calculate a transmission period (new PI) of a new probe packet based on the flow of data traffic according to the transmission of the probe packet. For example, when the flow of data traffic is high, the period calculator 913 can calculate a new PI by lowering the PI. If the flow of data traffic is low, the period calculator 913 may calculate a new PI as the PI increases.

Then, the period setting unit 911 can reset the PI with either a threshold value or a new PI. For example, if the new PI is larger than the threshold value, the period setting unit 911 can reset the PI from the threshold value to the new PI. Then, the transmission control unit 912 can transmit the data packet to the neighboring nodes according to the PI reset with the new PI. At this time, when the new PI is less than or equal to the threshold value, the period setting unit 911 can maintain the PI set as the threshold value. Then, the transmission control unit 912 can transmit the probe packet to the neighbor nodes according to the PI set as the threshold value.

The retransmission determining unit 920 can determine whether to retransmit the packet that failed to transmit using the data traffic flow and the switching point TP. 5 and 6, the retransmission determining unit 920 may set a turning point (TP) based on at least one of the routing success rate for the packet generation interval and the end-to-end delay for the packet generation interval .

For example, when the flow of data traffic is greater than the switching point, the retransmission determination unit 920 may determine retransmission of a packet that failed transmission. At this time, when the flow of the data traffic is less than the switching point, the retransmission decision unit 920 can decide not to retransmit the packet which failed in transmission. Here, the flow of the data traffic can be determined by checking the data packet transmitted according to the PI determined by the period determining unit 910 for a preset reference time.

The retransmission determination unit 920 may transmit at least one of the packet and the data packet that failed to be transmitted to the neighboring nodes based on the retransmission determination.

For example, when the retransmission is determined, the retransmission determining unit 920 may transmit the data packet to the neighboring nodes while retransmitting the failed transmission packet to the neighboring nodes.

As another example, when it is determined not to retransmit, the retransmission determining unit 920 can transmit the data packet to the neighboring nodes without retransmission of the packet that failed to transmit.

The link quality prediction unit 930 can predict the link quality using the link cost and the traffic weight calculated based on the flow of the data traffic. Referring to FIG. 11, the link quality prediction unit 930 may include a link cost calculation unit 931, a weight calculation unit 932, and a prediction unit 933.

The link cost calculator 931 can calculate the transmission link cost by assigning a weight according to the data traffic in the transmission direction. The link cost calculator 931 can extract the link cost from the routing information received from the candidate parent nodes and obtain the reception link cost.

The weight calculation unit 932 can calculate the transmission traffic weight and the reception traffic weight using the EWMA. At this time, the weight calculation unit 932 may calculate transmission traffic weights of the candidate parent nodes and calculate reception traffic weights of the candidate parent nodes, respectively.

The predicting unit 933 can predict the link quality of the candidate parent node based on the transmission and reception link costs and the transmission and reception traffic weights. In other words, the prediction unit 933 can predict the link quality of the candidate parent nodes, respectively. Here, the candidate parent node may be selected from neighboring nodes located around the routing device.

The routing unit 940 may determine the parent node based on the predicted link quality and the routing information received from the neighboring nodes, and may provide routing through the determined parent node. At this time, the routing unit 940 can provide cross-layer-based routing.

The routing unit 940 may update the routing table 950 based on the routing information received from the neighboring nodes. 12, the routing unit 940 may include a link quality comparison unit 941, a home count comparison unit 942, and a parent node determination unit 943. [

First, the link quality comparison unit 941 can compare the link quality of the current parent node with the link quality of the candidate parent nodes, respectively.

For example, if the link quality of the current parent node is better than the link quality of the candidate parent nodes, the parent node determination unit 943 can determine the current parent node as the parent node. Then, the routing unit 940 can continue to provide routing through the current parent node.

 As another example, if the link quality of the candidate parent nodes is better than the link quality of the current parent node, the link quality comparison unit 941 can check whether there is a candidate parent node having similar link quality among the candidate parent nodes. At this time, the link quality comparator 941 may select candidate parent nodes having better link quality than the current parent node, and calculate the link quality difference value between the selected candidate parent nodes. If the calculated difference value is within the preset reference range, the candidate parent nodes included in the reference range may be identified as nodes having similar link quality.

The hop count comparator 942 may then compare the hop counts of candidate parent nodes with similar link quality. At this time, the parent node determination unit 943 can determine a node having the smallest hop count among the candidate nodes having similar link quality as the parent node. Then, the routing unit 940 may continue to provide routing through the determined parent node. As described above, the routing unit 940 improves the reliability of the candidate parent node by determining the node having a shorter link count than the current parent node and having a shorter hop count as the parent node, and providing the routing using the determined parent node have.

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. This is possible.

Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by the equivalents of the claims, as well as the claims.

910:
920:
930: link quality prediction unit
940:
950: Routing table

Claims (17)

The routing device adaptively determining a transmission period of a probe packet based on a flow of data traffic;
Determining whether a routing device retransmits a packet that fails to transmit using the flow of data traffic and a turning point (TP);
Estimating a link quality using a link cost and a traffic weight calculated based on the flow of the data traffic; And
Wherein the routing device determines a parent node based on the predicted link quality
Lt; / RTI >
Wherein the step of adaptively determining the transmission period of the probe packet comprises:
Setting a transmission period of a probe packet as a threshold value through a network initialization, the probe packet being a metering packet used for predicting the link quality; And
Transmitting a probe packet to a neighbor node according to a transmission period of the probe packet set to the threshold value
/ RTI > The method according to claim 1,
Wherein the step of adaptively determining the transmission period of the probe packet comprises:
Setting a transmission period of a probe packet as a threshold value through network initialization, wherein the probe packet is a probe packet used for predicting the link quality;
Transmitting a probe packet to a neighboring node according to a transmission period of the probe packet set to the threshold value; And
Calculating a transmission period of a new probe packet based on a flow of data traffic according to transmission of the probe packet
/ RTI > 3. The method of claim 2,
Wherein the step of adaptively determining the transmission period of the probe packet comprises:
Resetting the transmission period of the probe packet to a transmission period of the new probe packet if the transmission period of the new probe packet is greater than the threshold value;
Transmitting the probe packet to the neighbor node according to a transmission period of the re-established probe packet
≪ / RTI > The method according to claim 1,
Wherein the step of determining whether to retransmit the packet comprises:
Determining to retransmit the packet that failed to transmit if the flow of data traffic is greater than the switch point;
Determining that a data packet is to be transmitted to neighboring nodes without retransmitting the failed transmission packet if the flow of data traffic is less than the switch point, the packet being generated in an application layer to provide a routing method A packet; And
Transmitting at least one of the packet and the packet that failed in the transmission based on the retransmission determination to a neighboring node
/ RTI > The method according to claim 1,
Wherein determining the parent node comprises:
Receiving routing information from neighboring nodes;
Selecting one of the current parent node and one or more candidate parent nodes as the parent node based on the hop count included in the received routing information
/ RTI > 6. The method of claim 5,
Wherein the step of selecting as the parent node comprises:
Comparing the link quality of the current parent node with the link quality of the candidate parent node;
Comparing the hop count of the current parent node and the hop count of the candidate parent node when the link quality of the current parent node and the link quality of the candidate parent node are included within a predetermined reference level through the link quality comparison ;
Determining a node selected through the hop count comparison as the parent node
/ RTI > A period determiner for determining a transmission period of the probe packet based on the flow of the data traffic,
A retransmission determining unit for determining whether to retransmit a packet that failed in transmission using the flow of data traffic and a turning point (TP);
A link quality predicting unit for predicting a link quality using a link cost calculated based on the flow of the data traffic and a traffic weight; And
A routing unit for providing routing via a parent node determined based on the predicted link quality,
Lt; / RTI >
Wherein the period determiner determines,
A period setting unit setting a transmission period of a probe packet as a threshold value through network initialization;
A transmission control unit for transmitting a probe packet to a neighboring node according to a transmission period of the probe packet set to the threshold value;
. delete 8. The method of claim 7,
Wherein the period determiner determines,
A period calculation unit for calculating a transmission period of a new probe packet based on the flow of data traffic according to the transmission of the probe packet,
Further comprising:
The transmission control unit,
And transmits the probe packet to the neighboring node according to any one of a transmission period of the calculated new probe packet and a transmission period of the set probe packet. delete delete delete delete delete delete delete delete

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