KR101474248B1 - METHOD OF ESTABLISHING ROUTING FOR 6LowPAN AND SYSTEM THEREOF - Google Patents

Abstract

The present invention relates to a method for enabling a resilient routing operation in a 6LoWPAN environment, and transmitting data using the routing operation. The present invention sets a recovery route as well as a main route from a starting node to a destination node when routing from the start node to the destination node. Accordingly, the present invention can use the recovery route in the event of a failure in a specific node during a data transmission operation to quickly respond to the failure.

Description

[0001] METHOD OF ESTABLISHING ROUTING FOR 6LOWPAN AND SYSTEM THEREOF [

BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention relates to a routing establishment method and apparatus of an IPv6 low power wireless personal area network (6LoWPAN). And more particularly, to a method and apparatus for establishing reliable and resilient routing of data transmission in a 6LoWPAN.

IETF (Internet Engineering Task Force) 6LoWPAN standard technology is being studied as a standard technology to support IPv6 (Internet Protocol version 6) packet communication in IoT (Internet of Things) environment. The 6LoWPAN standard is an organization that standardizes the architecture for using the Internet protocol on a low-power wireless personal network represented by IEEE (Institute of Electrical and Electronics Engineers) 802.15.4. Since 6LoWPAN operates on IPv6 basis, it provides a suitable sensor network environment compared to Zigbee and Bluetooth, and can be widely used in ubiquitous network environments requiring continuous data collection and transmission. Especially, in this network environment, the optimal routing protocol should be used according to the application used to transmit the data without any interruption and reliable connection between the nodes or the sensors.

6LoWPAN Ad-hoc On-Demand Distance Vector (LOAD) routing protocol that extends the AODV (Ad Hoc On-Demand Distance Vector) routing protocol, and Dynamic MANET On-demand for DYMO-Low 6LoWPAN Routing).

However, the LOAD routing protocol does not have a recovery path, and LOAD searches and re-establishes a new path when a node is defective (hardware fault, operating system malfunction, power exhaustion, noise, etc.). This process can generate unnecessary network traffic and cause long end-to-end latency. Such a routing method does not satisfy the QoS (Quality of Service) of the application of the ubiquitous network.

The QoS requirements of applications in 6LoWPAN may vary depending on the application used. In particular, U-Healthcare applications are time-critical, requiring faster recovery routing techniques.

Korean Patent No. 0969802

SUMMARY OF THE INVENTION The present invention provides a method for constructing resilient routing in 6LoWPAN.

The technical objects of the present invention are not limited to the above-mentioned technical problems, and other technical subjects not mentioned can be clearly understood by those skilled in the art from the following description.

According to an aspect of the present invention, there is provided a method of routing a 6LoWPAN according to an aspect of the present invention includes transmitting a routing request packet for establishing a primary route from a source node to a destination node via an intermediate node And transmitting a routing response packet to the destination node via the intermediate node when the destination node receives the routing request packet, wherein when the intermediate node receives the routing response packet, Establishing a recovery path from the originating node to the destination node, the intermediate node sending the routing response packet to a previous node on the primary route, and when the originating node receives the routing response packet, And constructing a recovery path to the destination node.

According to one embodiment, the intermediate node comprises a node excluding the originating node and the destination node on the main path, and the neighboring node may include a node at a one-hop distance from the specific node .

According to one embodiment, the source node, the intermediate node, the neighbor node, and the destination node include a routing table storing the route information of the main route and the recovery route, and the routing table includes a previous node column ), Next node column, neighbor node column, and recovery node column.

According to one embodiment, the step of transmitting the routing request packet via the intermediate node includes the steps of: when the intermediate node receives the routing request packet, transmitting the routing request packet to a neighbor node of the intermediate node; And the intermediate node updating the routing table of the intermediate node.

According to an embodiment, the step of updating the routing table may include selecting one of the neighbor nodes of the intermediate node as a next node using a link quality indicator (LQI) and an energy level, And storing the next node in the next node column of the routing table of the intermediate node.

According to one embodiment, the step of establishing a recovery path by the intermediate node includes the steps of the intermediate node sending a recovery path setting packet to a neighbor node of the intermediate node, and when the neighboring node receives the recovery path setting packet If the path information to the destination node is not stored in the routing table of the neighbor node, transmits a recovery path response packet to the intermediate node if the path information to the destination node is stored in the routing table of the neighbor node, Transmitting to the neighboring node of the neighboring node, and when the intermediate node receives the recovery path response packet, storing the sender node of the recovery path response packet in the recovery node column of the routing table of the intermediate node have.

According to one embodiment, the step of the originating node constructing a recovery path may include the steps of the originating node transmitting a recovery path setting packet to a neighboring node of the source node, receiving the recovery path setting packet If the path information to the destination node is stored in the routing table of the neighbor node, the recovery path response packet is transmitted to the source node, and if the path information to the destination node is not stored, Transmitting the recovery path setup packet and storing the originator node of the recovery path response packet in the recovery node column of the source node's routing table when the source node receives the recovery path response packet have.

According to another aspect of the present invention, there is provided a routing construction system for a 6LoWPAN, the routing construction system comprising: a main path up to a destination node by transmitting a routing request packet; A destination node for establishing a recovery path, and a router for transmitting the route setting request packet until the route setting request packet is transmitted to the destination node, And an intermediate node for establishing a recovery path up to the node and transmitting the routing response packet to the source node. The destination node, when receiving the routing request packet from the intermediate node, To the intermediate node.

According to one embodiment, the source node, the intermediate node, and the destination node belong to a 6LoWPAN-based multi-hop wireless network and may have an Internet Protocol version 6 (IPv6) standard IP address.

According to one embodiment, the source node, the intermediate node, the neighbor node, and the destination node include a routing table storing the route information of the main route and the recovery route, and the routing table includes a previous node column ), Next node column, neighbor node column, and recovery node column.

According to one embodiment, the source node transmits a recovery path setup packet to the destination node to construct the recovery path, and upon receiving the recovery path response packet, transmits the source node of the recovery path response packet to the source node It can be stored in the recovery node column of the routing table.

According to one embodiment, the intermediate node transmits a recovery path setup packet to the destination node to construct the recovery path, and when receiving the recovery path response packet, transmits the recovery path response packet to the intermediate node, It can be stored in the recovery node column of the routing table.

According to the present invention, when restoring the routing in the 6 LowWPAN environment and transmitting the routing data, if a failure occurs on the routing, the burden on the entire network can be reduced by reliably restoring the failed node .

FIGS. 1A through 4B illustrate a process of constructing a main path according to an embodiment of the present invention.
5A and 8B illustrate a process of constructing a recovery path according to an embodiment of the present invention.
FIGS. 9A and 9B illustrate a method of using a recovery path in the event of a failure, according to an embodiment of the present invention.
10 is a message flow diagram for establishing a main path and a recovery path according to an embodiment of the present invention.
11 is a message flow diagram for transmitting data using a recovery path, in accordance with an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Unless defined otherwise, all terms (including technical and scientific terms) used herein may be used in a sense commonly understood by one of ordinary skill in the art to which this invention belongs. Also, commonly used predefined terms are not ideally or excessively interpreted unless explicitly defined otherwise.

The present invention utilizes routing built on 6LoWPAN to overcome data transmission failures on 6LoWPAN. The routing may include a primary path and a recovery path and may overcome the data transmission failure by resuming the data transmission using the recovery path at a node located on the primary path where a data transmission failure occurs.

Accordingly, a method of establishing routing including the main path and the recovery path will be described below, and a method of overcoming the transmission failure when a data transmission failure occurs using the established routing will be described.

First, referring to FIG. 1A, the 6LoWPAN environment will be described in detail.

6LoWPAN is an IPv6 based low power wireless local area network. Each node of 6LoWPAN has a separate IP address of IPv6. Each node has a routing table internally storing routing information. The routing table may be updated at the time of establishing the main path and the recovery path.

For convenience of explanation, it is assumed that each node is arranged in the 6LoWPAN as shown in FIG. 1A. B12 and B13 of the intermediate node P1 and the neighboring nodes B21 and B22 of the intermediate node P2 and the intermediate nodes P1 and P2 of the intermediate node P1 are set as the destination node S and the destination node D, ).

Next, referring to FIG. 1B, a routing table 200 existing in each node of the 6LoWPAN will be described. The routing table 200 may include an old node column 210, a next node column 220, a neighbor node column 230, and a recovery node column 240.

Each column of the routing table 200 will be described using an arbitrary node A on the main path stored in the routing table 200 as follows.

The previous node column 210 stores the node information immediately before the node A on the main path. In the next node column 220, the next node information of the node A is stored on the main path. In the neighbor node column 230, information of a node adjacent to the node A and having a hop count of 1 and the node A is stored. In the recovery node column 240, information of a node bypassing a node stored in the next node column 220 when a failure occurs in the main path is stored. The information of the node stored in each column may include the IP address of the node.

Referring now to Figures 2a-8b, a method for establishing resilient routing in a 6LoWPAN is described.

The source node S broadcasts a Routing Request (RRQE) packet to a neighbor node of the source node S to establish a main route. The broadcasting refers to a transmission method in which a specific node is not transmitted to a destination but is transmitted to an unspecified node. The neighbor node having received the route setting request packet transmits a response signal (ACK) to the source node S in response thereto. The response signal ACK may include an IP address of a node that transmitted the ACK, a link quality indicator (LQI), and an energy level of a signal. The link quality index is an index indicating a value proportional to the signal strength of the acknowledgment signal (ACK).

The source node S receives the acknowledgment ACK and transmits the information of the neighboring nodes P1, B11 and B12 which transmitted the acknowledgment ACK to the neighboring nodes P1, B11 and B12 of the source node S in the routing table 300, Can be stored in a column.

The source node S may receive the response signal ACK and may select the next node on the main path and store the selected node in the routing table 300. [ The source node S may select a node having the smallest minimum link quality index included in the acknowledgment signal ACK among the neighbor nodes that have transmitted the acknowledgment ACK as the next node. If the minimum value of the link quality index is the same, the node having the highest energy level among the neighboring nodes may be selected as the next node. For convenience of explanation, the source node S selects the node P1 as the next node.

Referring to FIG. 1B, a node P2 is stored in the next node column of the routing table 300, and neighboring nodes B11 and B12 are stored in the neighbor node column of the table 300 except for the node P1.

The node P1 selected as the next node by the source node S becomes an intermediate node. The intermediate node includes a node located between the source node (S) and the destination node (D) on the main path.

The source node S may transmit the routing request packet to the node P1 in a unicast manner to notify that the node P1 has been selected as the next node. The routing request packet may include a hop count indicating a distance from the source node S. [ For example, the routing request packet transmitted from the source node S to the node P1 may include a hop count having a value of one. The hop count may be increased to a certain size each time the node moves by one. For example, if the routing request packet is transmitted to another node, the hop count included in the routing request packet may be incremented by one.

3A, a method of constructing the main path by the node P1, which is an intermediate node, will be described.

The node P1 can confirm that the previous node is the source node S on the main route using the sender IP included in the received route setting request packet. The node P1 stores the source node S in the previous node column of the routing table 300. [

The node P1 broadcasts a route setting request packet to the neighboring nodes B11, B12, B13 and P2. The neighboring nodes B11, B12, B13, and P2, which have received the routing request packet, transmit a response signal (ACK) to the node P1 in response thereto. The response signal ACK may include the IP address of the node B11, the node B12, the node B13, or the node P2 that has transmitted the response signal ACK, the link quality index, and the energy level of the node.

The node P1 may receive the acknowledgment ACK and store the information of the neighboring nodes B11, B12, B13 and P2 that transmitted the acknowledgment ACK in the neighboring node column of the routing table 400 of the node P1 have.

The node P1 may receive the response signal (ACK), select the next node on the main path, and store the selected node in the routing table 400. The node P1 selects the node having the largest minimum link quality index included in the acknowledgment signal ACK among the neighbor nodes B11, B12, B13 and P2 that transmitted the acknowledgment ACK as the next node . If the minimum value of the link quality index is the same, the node having the highest energy level can be selected as the next node. For convenience of explanation, the node P1 selects the node P2 as the next node.

3B, the node P2 is stored in the next node column of the routing table 400, and the neighbor nodes B11, B12, and B13 are stored in the neighbor node columns of the routing table 400 except for the node P2.

The node P1 can transmit the routing request packet to the node P2 again in a unicast manner to notify that the node P2 has been selected as the next node. The routing request packet transmitted from the node P1 to the node P2 may include a hop count having a value of 2.

Referring to FIG. 4A, a method of constructing the main path at an intermediate node P2 will be described.

The node P2 can confirm that the previous node is the node P1 on the main path by using the sender IP included in the received route setting request packet. Node P2 stores node P1 in the previous node column of routing table 400. [

The node P2 broadcasts a route setting request packet to the neighboring nodes B21, B22, and D. The neighboring nodes B21, B22, and D, which have received the routing request packet, transmit a response signal ACK to the node P2 in response thereto. The response signal ACK may include the IP address of the node B21, B22, D that transmitted the acknowledgment ACK, the link quality index, and the energy level of the node.

The node P2 may receive the acknowledgment ACK and store the information of the neighboring nodes B21, B22 and D that transmitted the acknowledgment ACK in the neighboring node column of the routing table 500 of the node P2.

The node P2 may receive the acknowledgment signal ACK and may select the next node on the main path and store it in the routing table 500. [ The node P2 determines whether the IP address of the acknowledgment signal ACK is the same as the IP address of the destination node D. [ Since the destination node D exists among the neighboring nodes B21, B22, and D of the node P2, the next node of the node P2 becomes the destination node D. [

Referring to the routing table of FIG. 4B, the destination node D is stored in the next node column of the routing table 500 of the node P2, and the neighbor node column of the routing table 500 stores the neighbor node (B21, B22) are stored.

The node P2 can complete the main path construction by once again sending the routing request packet having the hop count value of 3 to the destination node D. [

Upon receipt of the routing request packet, the destination node D checks whether the IP address of the routing request packet exists in the routing table 600. If the sender IP does not exist in the routing table 600, the node P 2 is stored in the previous node column of the routing table 600. If the originator IP exists in the routing table 600, the hop count of the routing request packet is compared with the hop count of the existing hop count stored in the routing table 600. If the hop count of the routing request packet is smaller, The previous node column value of the table 600 is replaced with the node P2. For convenience of explanation, assuming that there is no existing main path, the destination node D stores the node P2 in the previous node column of the routing table 600. [

Referring to FIG. 4B, the routing table 600 of the destination node D can know that the node P2 is stored only in the previous node column.

5A to 8B, recovery path construction will be described. When the destination node D receives the route setting request packet, the destination node D can start building the recovery route.

Referring to FIG. 5A, the destination node D may transmit a Route Reply (RREP) packet to the node P2 unicast.

Upon receiving the routing response packet, the node P2 broadcasts a BREQ (Bakcup Route Request) packet to a node stored in the neighbor node column of the routing table 500. [

The nodes B21 and B22 receiving the backup path setup request packet broadcast the received backup path setup request packet. When the destination node D receives the backup route setup request packet, it transmits a BREP (Baking Route Reply) packet to the sender B21 of the backup route setup request packet in response to the backup route setup request packet. The node B21 having received the backup path setup response packet transmits the backup path setup response packet to the node P2.

Upon receiving the backup path setup response packet, the node P2 stores the node B2 in the recovery node column of the routing table 500. [ Referring to FIG. 5B, the stored value of the routing table 500 of the node P2 in which the main path and the recovery path have been established can be known.

Referring to FIG. 6A, upon receiving the backup path setup response packet, node P2 transmits a routing response packet to node P1, which is a previous node of node P2 on the primary path.

Upon receiving the routing response packet, the node P1 transmits a backup path setup request packet to the neighbor nodes B11, B12, and B13 stored in the neighbor node columns of the routing table 400. [ The nodes B11, B12, and B13 that have received the backup path setup request packet broadcast the backup path setup request packet. The node having the path from the node receiving the broadcasted backup path setup request packet to the destination node D transmits a backup path setup response packet to the sender of the received backup path setup request packet. Since the node B21 has a route to the destination node D as a neighbor node of the destination node D, the node B21 transmits the backup path response packet to the node B11. The node B11 receives the backup path response packet and transmits the backup path response packet to the node P1.

Upon receiving the backup path response packet, the node P1 stores the node B11 in the recovery path column of the routing table 400. [

6B, in the routing table of the node P1, the source node S is stored in the previous node column, the node P2 is stored in the next node column, the node B11, the node B12, and the node B13 are stored in the neighbor node column, Node B11 is stored.

With reference to FIG. 7A, construction of a recovery path at a source node will be described.

Upon receiving the backup path response packet, the node P1 transmits the routing response packet to the source node S stored in the previous node column of the routing table 400. [

Upon receiving the routing response packet, the source node S transmits a backup route request packet to the neighbor nodes B11 and B12 stored in the neighbor node column of the routing table 300. [ The node B11 having a path from the neighbor nodes B11 and B12 to the destination node D transmits a recovery path setting response packet to the source node S.

Upon receiving the recovery path setup response packet, the source node S stores the sender node B11 of the recovery path setup response packet in the recovery path column of the routing table 300. [

Referring to FIG. 7B, node P1 is stored in the next node column of the routing table 300 of the source node S, nodes B11 and B12 are stored in the neighbor node column, and node B11 is stored in the recovery path column.

When the source node S receives the path setting response packet and the recovery path setting response packet, both the transmission path setting and the recovery path setting are completed.

Referring to FIG. 8A, a network diagram 150 of FIG. 8A illustrates a main path (solid line) and a recovery path (dotted line) constructed according to the routing path construction method of the present invention in a 6LoWPAN environment.

The main path is connected from the source node S to the node P1, from the node P1 to the node P2, and from the node P2 to the destination node D.

The recovery path is the recovery node of the source node S, the recovery node of the node P1 is the node B11, and the recovery node of the node P2 is B21.

8B is a routing table 300, 400, 500, 600 of each of the nodes S, P1, P2, and D existing on the main path constructed according to the routing path construction method of the present invention.

Referring to FIG. 9, a message flow of a routing construction method including a main path and a recovery path according to an embodiment of the present invention will be described.

The route setting request message is transmitted from the source node S to the node P1 (S110). The routing request message is transmitted from the node P1 to the neighboring node B11 (S112). The neighboring node B11 transmits a response message to the node P1 (S114). The node P1 stores the neighboring node B11 in the neighboring node column of the routing table of the node P1 (S115). The node P1 transmits the route setting request message to the node P2 (S120).

The node P2 transmits the routing request message to the neighboring node B21 (S122). The neighboring node B21 transmits a response message to the node P2 (S124). The node P2 stores the node B21 in the neighbor node column of the routing table of the node P2 (S125). The node P2 transmits a route setting request message to the destination node D (S127).

The destination node D transmits a routing response message to the node P2 (S130).

The node P2 transmits a backup path setup request message to the neighboring node B21 (S132). The node B21 transmits a backup path setup response message to the node P2 (S134). The node P2 stores the node B21 in the recovery node column of the routing table of the node P2 (S135). The node P2 transmits a routing response message to the node P1 (S140).

The node P1 sends a backup path setup request message to the neighboring node B11 (S142). The neighboring node B11 transmits a backup path setup response message to the node P1 (S144). The node P1 stores the node B11 in the recovery node column of the routing table of the node P1 (S145). The node P1 transmits a routing response message to the source node S (S150).

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, You will understand. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

Network configuration diagram 100

Claims (12)

Transmitting a routing request packet for establishing a primary route from a source node to a destination node via an intermediate node;
When the destination node receives the route setting request packet, transmitting a route setting response packet to the destination node via the intermediate node;
Constructing a recovery path from the intermediate node to the destination node when the intermediate node receives the routing response packet;
The intermediate node sending the routing response packet to a previous node on the primary route; And
And constructing a recovery path from the originating node to the destination node when the originating node receives the routing response packet,
Wherein the source node, the intermediate node, the neighbor node, and the destination node include a routing table storing path information of the main path and the recovery path,
The routing table includes a previous node column, a next node column, a neighbor node column, and a recovery node column,
Wherein the intermediate node establishing a recovery path comprises:
The intermediate node sending a recovery path setup packet to a neighbor node of the intermediate node;
When the neighbor node receives the recovery path setup packet, transmits the recovery path response packet to the intermediate node if the routing information to the destination node is stored in the routing table of the neighbor node, If not, transmitting the recovery path setup packet to a neighbor node of the neighbor node; And
When the intermediate node receives the recovery path response packet, storing the source node of the recovery path response packet in the recovery node column of the routing table of the intermediate node,
Wherein the intermediate node includes a node excluding the source node and the destination node on the main path,
Wherein the neighboring node comprises a node at a one-hop distance from a particular node,
6 How to build routing for IPv6 Low Power Personal Area Network (LoWPAN). delete delete The method according to claim 1,
Wherein the transmitting the routing request packet via an intermediate node comprises:
Transmitting the routing request packet to a neighbor node of the intermediate node when the intermediate node receives the routing request packet; And
The intermediate node updating the routing table of the intermediate node,
How to build routing for 6LoWPAN. 5. The method of claim 4,
Wherein updating the routing table comprises:
Selecting one of the neighbor nodes of the intermediate node as a next node using a link quality indicator (LQI) and an energy level; And
And storing the next selected node in the next node column of the routing table of the intermediate node.
How to build routing for 6LoWPAN. delete The method according to claim 1,
The step of the originating node establishing a recovery path comprises:
The originating node sending a recovery path setup packet to a neighbor node of the source node;
When the neighbor node receives the recovery path setup packet, transmits a recovery path response packet to the source node if the routing information to the destination node is stored in the routing table of the neighbor node, Transmitting the recovery path setup packet to a neighbor node of the neighbor node if the node is not stored; And
Storing the originator node of the recovery path response packet in a recovery node column of the routing table of the source node when the source node receives the recovery path response packet.
How to build routing for 6LoWPAN. A source node for establishing a main path to a destination node by transmitting a path setting request packet and constructing a recovery path to the destination node upon receiving a path setting response packet; And
Upon receipt of the route setting request packet, the main path construction is continued and the routing request packet is transmitted until it is delivered to the destination node. Upon receiving the routing response packet, a recovery route to the destination node is established And an intermediate node for transmitting the routing response packet to the source node,
Wherein the destination node transmits the routing response packet to the intermediate node upon receiving the routing request packet from the intermediate node,
Wherein the source node, the intermediate node, the neighbor node, and the destination node include a routing table storing path information of the main path and the recovery path,
The routing table includes a previous node column, a next node column, a neighbor node column, and a recovery node column,
Wherein the intermediate node comprises:
And transmits the recovery path response packet to the destination node in order to construct the recovery path. When the recovery path response packet is received, the source node of the recovery path response packet is stored in the recovery node column of the routing table of the intermediate node,
The source node, the intermediate node, and the destination node,
It belongs to 6LoWPAN based multi-hop wireless network and has IP address of IPv6 (Internet Protocol version 6)
6LoWPAN routing building system. delete delete 9. The method of claim 8,
The source node,
Storing a recovery path setup packet in the recovery node in the routing table of the source node when the recovery path response packet is received and transmitting the recovery path setup packet to the destination node in order to construct the recovery path,
6LoWPAN routing building system. delete

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