KR20120134466A - Mesh network node and data transferring method thereof - Google Patents

Abstract

The present invention discloses a mesh network node and a data transmission method of the wireless mesh network system.
In the data transmission method using the Stream Control Transmission Protocol (SCTP) of the mesh network node of the present invention, a transmission node detects a failure of the main path during data transmission to a receiving node through a first network interface of the main path for transmitting data. And setting a new primary path by changing a first network interface of the primary path to a second network interface of a secondary path in an upper layer of the data link layer based on the path state information collected by the data link layer. And transmitting data to the receiving node via the second network interface.

Description

Mesh network node and data transferring method

The present invention relates to a mesh network node of a wireless mesh network system and a data transmission method thereof.

A new wireless network technology for overcoming the limitations of the wireless LAN is a wireless mesh network technology. This wireless mesh network technology is expected to play an important role as next generation low power wireless technology for U-Port, U-City (Ubiquitous City), wireless CCTV (IP camera) in airport. In particular, it is expected to be used as a next-generation (4G) mobile communication network by applying it to various areas such as areas where urban networks are difficult to install, urban networking, home networking, and sensor networking.

Wireless Mesh Network is a technology in which fixed wireless routers are connected by multi hops to form a wireless backhaul network. In the wireless mesh network, there is a special type of wireless router called one or several gateways, and the gateway serves as a path connecting the wireless router and the external internet network on the wireless mesh network. Each of the wireless routers provides a wireless communication service to lower nodes to perform a function of a wireless backhaul network.

In terms of routing, the wireless mesh network is composed of fixed wireless routers, so there is almost no change in network topology, and the ubiquitous wireless infrastructure in fixed spaces such as schools, hospitals, and companies It can be used as a cheap and easy to build technology. The network topology represents the arrangement of a plurality of devices interconnected by a communication link in the form of a network.

In the wireless mesh network, when a part of the terminal (or link) constituting the current path becomes incapable of communication, the time delay is delayed because the entire path must be newly reset through the router resetting between the entire ends. Impossible problems can occur.

The present invention provides a system that can quickly respond to a failure in the path of the network by using the multihoming function of the SCTP protocol in a wireless mesh network.

In a data transmission method using a Stream Control Transmission Protocol (SCTP) of a mesh network node having a multi-network interface according to an exemplary embodiment of the present invention, a transmitting node receives a data through a first network interface of a main path for transmitting data. Detecting a failure of the main path during data transmission to a node; And setting a new primary path by changing a first network interface of the primary path to a second network interface of a secondary path in an upper layer of the data link layer based on the path state information collected by the data link layer. It may include.

The newly establishing the primary path may include transmitting a request for a path change from the primary path to the secondary path at the data link layer to the network layer; Acquiring, by the network layer, an IP address of the second network interface based on the path state information and transmitting a network interface IP address change to a transport layer based on the path state information; Setting a new primary path by changing the first network interface IP address to the second network interface IP address in the transport layer; And notifying the receiving node of a major path change using the SCTP at the transport layer.

The path state information may include bandwidth, data rate and data rate.

The transmitting node may monitor the auxiliary path by transmitting a heartbeat message to the receiving node through the network interface of each auxiliary path.

The path failure may include a failure of a network interface, a network failure, and a reduction in data rate due to congestion control.

Each layer may transmit and receive data to and from each other based on a cross layer.

The method may further include transmitting data to the receiving node via the second network interface.

An apparatus for transmitting and receiving data of a mesh network node using SCTP according to an embodiment of the present invention includes: a plurality of network interfaces; A path state detection unit for collecting path state information through each network interface and detecting a failure of the main path during data transmission to a counterpart node through a first network interface of a main path for transmitting data; A path selector configured to select a second network interface among network interfaces of an auxiliary path based on the path state information in a network layer; And a path setting unit configured to set the second network interface as the main path in the transport layer, and notify the counterpart node of the main path change through the second network interface using a stream control transmission protocol (SCTP). can do.

The apparatus for transmitting and receiving data may further include a layer manager which stores the path state information and mediates data transmission and reception between layers based on a cross layer.

The mesh network node may include a mesh gateway, a mesh router, and a mesh client of a wireless mesh network.

In accordance with another aspect of the present invention, a wireless mesh network system includes: a mesh gateway connected to a wired network to exchange traffic of a mesh network with a wired backbone network through a backbone link; A mesh router connected to the mesh gateway through a wireless mesh link; And a mesh client connected to the mesh router through a user link and transmitting and receiving data to and from an external server through the mesh router and the mesh gateway. The mesh gateway, the mesh router, and the mesh client include a multi-network interface. In addition, data may be transmitted and received through the multi-network interface using a stream control transmission protocol (SCTP), and data may be transmitted and received between layers based on a cross layer.

The present invention can increase the data transfer rate between mesh network nodes by using the multihoming function by using the SCTP transmission protocol in the mesh network environment.

In addition, the present invention can provide a seamless communication service between mesh network nodes based on the cross-layer architecture.

1 is a view schematically showing the structure of a wireless mesh network according to an embodiment of the present invention.
2 is a diagram illustrating an example of transmitting and receiving data using the multi-homing characteristic of SCTP between mesh network nodes according to an embodiment of the present invention.
3 is a diagram illustrating an Open Systems Interconnection (OSI) layer diagram of a mesh network node according to an embodiment of the present invention.
4 to 7 are diagrams for explaining a method of performing data transfer and function between layers of a mesh network node based on a cross layer according to an embodiment of the present invention.
8 is a diagram illustrating a data transmission method of a mesh network node using SCTP according to an embodiment of the present invention.
9 is a block diagram schematically illustrating an apparatus for transmitting and receiving data of a mesh network node using SCTP according to an embodiment of the present invention.
10 is a flowchart illustrating a data transmission method between mesh network nodes using SCTP according to an embodiment of the present invention.
11 is a flowchart illustrating a method of changing a data transmission path by a mesh network node using SCTP according to an embodiment of the present invention.
12 illustrates a conventional Open Systems Interconnection (OSI) hierarchy diagram.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a view schematically showing the structure of a wireless mesh network according to an embodiment of the present invention.

The wireless mesh network has a first automatic network configuration function. This feature automatically configures the mesh network topology in a wireless environment at all times. Accordingly, it is possible to increase the reliability of the communication according to the multipath as compared to the existing point-to-multipoint wireless communication method with low survivability. Such characteristics are useful in applications where existing communication infrastructures, such as firefighting and disaster communication, military communication, are poor, or need to be automatically configured and communicated immediately depending on the situation.

The wireless mesh network has a second automatic network recovery function. Since the wireless mesh network is not a single path communication method, if a problem occurs in the terminal (node) due to physical switching or traffic overload in the terminal (node) to which the communication was performed, the optimal new routing path is found in the current network. . For this network recovery, all terminals (nodes) periodically search for the optimal radio link, calculate the amount of traffic and delay rate, etc. processed in their own terminals, so as to configure an optimal communication network.

Referring to FIG. 1, the wireless mesh network of the present invention includes a mesh gateway (MG), a mesh router (MR), and a mesh client (MC).

The mesh gateway (MG) is a special mesh router with a wired interface that connects to the outside Internet at high speed. The mesh gateway (MG) is connected to the wired network to exchange traffic of the mesh network with the wired backbone network through the backbone link. .

The mesh router MR is connected to the mesh gateway MG via a wireless mesh link to provide a service to the mesh client MC, which is a user node spreading over a wide area. The mesh router MR may perform an access ponit (AP) function.

The mesh client MC is a terminal of a mobile phone, a PDA, a notebook computer, and the like.

The mesh network includes a user link connecting the mesh client (MC) and the mesh router (MR), and a mesh link connecting the mesh routers (MR) or connecting the mesh router (MR) and the mesh gateway (MG). Depending on the type of communication technology used, it may be classified into a heterogeneous mesh or a homogeneous mesh network.

The mesh gateway (MG), mesh router (MR), and mesh client (MC) use the Stream Control Transmission Protocol (SCTP) as the transport layer protocol. Each of the mesh gateway MG, the mesh router MR, and the mesh client MC may have one or more communication interfaces to perform a multi-homing function of performing communication through a plurality of interfaces. Each of the mesh gateway MG, the mesh router MR, and the mesh client MC may transmit and receive data between layers based on the cross layer.

Although not shown, the server communicating with the mesh gateway (MG) also has a multi-homing function of using SCTP as a transport layer protocol, and having one or more communication interfaces to perform communication through a plurality of interfaces, and based on a cross layer. You can send and receive data to and from each other.

SCTP is a transport protocol proposed by the IETF SIGTRAN Working Group as standard in October 2000 (RFC 2960) to transmit signaling messages used in the PSTN network on an IP network of the Internet. In addition, SCTP is a connection-oriented protocol such as TCP that operates on the IP layer to enable reliable data transmission and to protect against DOS attacks or masquerading attacks that can occur during association control. It is designed. In addition, SCTP has a multi-streaming feature to solve the performance degradation caused by TCP's Head Of Line Blocking, and in particular, multi-homed where SCTP-connected nodes can have multiple IPs. In case of multi-homed, multi-homing function can be used to transmit data to other communication paths even if a path failure occurs in the primary path by adjusting a plurality of communication paths, thereby improving reliability of data transmission. Can be.

The multi-homing nature of SCTP allows mesh routers (MRs) and mesh clients (MCs) to use more than one IP in a session, which enables fail-over and fast loss recovery for path failures. Etc. can be provided. SCTP has two structures (Associations), so if one connection fails, the data is retransmitted to the other one, making it more reliable than TCP, UDP, and RTP. Therefore, the mesh router (MR) and the mesh client (MC) using SCTP can overcome the communication failure in a short time by using another interface connection, even if one interface or the network to which it belongs does not operate, The communication with the receiver can be continued without interruption.

2 is a diagram illustrating an example of transmitting and receiving data using the multi-homing characteristic of SCTP between mesh network nodes according to an embodiment of the present invention.

The mesh network node includes a mesh gateway (MG), a mesh router (MR) and a mesh client (MC) of a wireless mesh network.

Each mesh network node has at least one network interface card (NIC) supporting a network interface (hereinafter, referred to as a network interface). The network interface includes a portable Internet interface supporting Wibro, a wireless LAN interface supporting wireless LAN, a CDMA interface supporting CDMA communication, and the like. The network interface (NIC) is responsible for some functions of the physical layer described later and performs the functions.

Two adjacent mesh network nodes that are SCTP-connected each have one or more network interfaces (multi-network interfaces), so that there are two or more physical paths for transmitting and receiving data between the two mesh network nodes. One network interface corresponds to one path, so a path change represents a network interface change. The path through which data is transmitted is called a primary path, and the other unused path is called a secondary path.

Two mesh network nodes that are SCTP-connected (sending and receiving nodes) are multi-homed nodes with IPs assigned to each of the multi-network interfaces, and the first SCTP connection of IPs assigned to two or more available network interfaces. When the mutual IP is exchanged, a data transmission path corresponding to each IP is secured.

After the connection is established, the transmitting node selects one of several paths and uses it as the main path for data transmission, and the other paths are idle as auxiliary paths. In this case, the transmitting node may check whether the auxiliary path is available by using a HEARTBEAT message.

When two or more physical paths exist between the transmitting node and the receiving node, the transmitting node periodically transmits the heartbeat message to the receiving node through all the paths, and receives the heartbeat ACK from the receiving node.

The transmitting node periodically generates a HEARTBEAT message and delivers it to the receiving node. The receiving node receiving the heartbeat message sends a heartbeat acknowledgment (ACK) to the transmitting node to notify normal reception.

The transmitting node may determine a path failure by receiving an ACK (heartbeat ACK, data ACK). The transmitting node may determine that a path has failed if an ACK is not received. The transmitting node may analyze the ACK to measure a response time (Round Trip Time, hereinafter, referred to as 'RTT'), and measure a bandwidth and a transmission speed of a path based on the RTT.

The transmitting node may select a main path to transmit data based on the path state information obtained using the heartbeat message. The path state information obtained using the heartbeat message includes a path ID, bandwidth, and the like.

When one network interface is set as the main path, the transmitting node transmits data to the receiving node through the configured network interface. At the same time, the sending node continues to send heartbeat messages to the receiving node periodically through the auxiliary path to collect path status.

When the network node of the primary path fails, the transmitting node selects the network interface of one auxiliary path based on the path state information. The transmitting node can seamlessly transmit data through the network interface of the selected secondary path.

Referring to FIG. 2A, when one network interface is set as the main path, the transmitting node transmits data to the receiving node through the configured network interface. At the same time, the sending node continues to send heartbeat messages to the receiving node periodically through the network interfaces of the auxiliary path to collect path status information.

The transmitting node detects a failure (network interface failure, network failure, etc.) in the main path and performs a path change process.

Referring to FIG. 2B, the transmitting node selects one network interface among the network interfaces of the auxiliary path, and changes the selected network interface to the primary path. As a result, the failed network interface is changed to the secondary path.

The transmitting node transmits data to the receiving node through the newly selected network interface. At the same time, the sending node continues to send heartbeat messages to the receiving node periodically through the network interfaces of the auxiliary path to collect path status.

3 is a diagram illustrating an Open Systems Interconnection (OSI) layer diagram of a mesh network node according to an embodiment of the present invention.

Referring to FIG. 3, the mesh network node of the present invention processes an internal process based on a cross-layer architecture, which is a new hierarchical approach that allows easy control and data movement between layers for information.

As shown in FIG. 12, since the conventional protocol structure for each layer is used, each layer is independent and strongly separated. This feature makes it difficult to deliver data and control information to the desired layer.

On the other hand, the cross-layer architecture is basically organic and hierarchical data exchange like the OSI protocol when exchanging data between protocol stack layers, and data can be transmitted and received by any protocol stack that requires data exchange characteristic of the cross layer.

The physical layer is a layer that is in charge of the transmission, and defines mechanical, electrical, functional, and procedural characteristics for activating and managing a link for data transmission between two connected nodes. The physical layer converts a packet formed through higher layers into an electrical signal, and transmits and receives data using a physical medium (eg, a frequency) as a transmission medium.

The data link layer is a layer for reliably transmitting data through a physical link. The data link layer is responsible for physical addressing, network topology, physical link management, error notification, logical frame composition, flow control, and the like.

The network layer has data transmission and path selection functions for connecting to a higher layer. The network layer can use the routing protocol to select the optimal path. The protocol of the network layer is IP (Internet Protocol).

The transport layer uses SCTP as a protocol to ensure reliable data transmission between SCTP-connected mesh network nodes by securing data transmission paths between mesh network nodes. The transport layer is responsible for error recovery and congestion control.

The application layer receives data from the user and delivers the data to the lower layer, and delivers the data received from the lower layer to the user. The application layer functions as a user interface and application software using network data.

The present invention can deliver and notify lower layer information to a higher layer by cross-layer optimization, and the upper layer can process the information at high speed using the information received from the lower layer. Conversely, the upper layer information can be delivered to the lower layer, and the lower layer can perform information processing using the information of the upper layer.

4 to 7 are diagrams for explaining a method of performing data transfer and function between layers of a mesh network node based on a cross layer according to an embodiment of the present invention.

4 to 7, each layer performs a function based on path state information of the data link layer.

Referring to FIG. 4, the data link layer collects path state information. Here, the path state information includes a path ID, a bandwidth, a data rate, and a data rate. The data link layer may determine path failure and availability based on the path state information.

The data link layer monitors the ever-changing network environment and measures the bandwidth available at each network interface. The available bandwidth can be measured by the RTT value. As another example, the bandwidth of the transmission path may be set in advance by the server for each path.

First, a method of performing a function of a network layer will be described with reference to FIGS. 4 and 5.

The data link layer collects path state information (S501).

The network layer may select an optimal path to transmit data based on the path state information collected by the data link layer (S503). The network layer may obtain a network interface IP address of the selected path and forward it to the SCTP transport layer.

The SCTP transport layer establishes a path such that data is transmitted through a network interface having an IP address received from the network layer (S505).

The application layer may set a data transmission amount and a transmission rate based on the available bandwidth in the path set in the SCTP transport layer (S507). The application layer may check the available bandwidth of the path based on the path state information of the data link layer.

SCTP connection of the present invention can transmit data without delay by using information of the lower layer in the upper layer in a fast time by the cross layer architecture.

Next, a method of performing a function of the SCTP transport layer will be described with reference to FIGS. 4 and 6.

The data link layer collects path state information (S601).

The SCTP transport layer performs congestion control to suppress the amount of data transmission based on the path state information (S603). Congestion is defined as an excessive increase in the number of packets present in the network. Congestion control is a function of preventing or eliminating congestion. For example, the SCTP transport layer adjusts the data transfer amount according to network conditions, such as when communication at a lower layer is interrupted due to congestion, packet loss occurs, and network conditions deteriorate. Can be. If the available bandwidth is reduced according to the network situation, it will try to inject a large amount of data into the narrow network bandwidth, increasing the load on the network. The SCTP transport layer can request the application layer to change the data rate and rate based on the detected bandwidth change in the data link layer.

The application layer changes the data transmission amount and the transmission rate according to the congestion control of the SCTP transport layer (S605).

The data link layer collects path state information after congestion control of the SCTP transport layer (S607). When congestion control is performed, the data rate drops drastically. The data link layer can detect such a change in data rate.

If the data link layer detects a change in the data rate on the path, the network layer may select an optimal path to transmit data based on the path state information collected by the data link layer (S609). The network layer obtains the network interface IP address of the selected route and forwards the IP address change to the SCTP transport layer.

The SCTP transport layer establishes a path so that data is transmitted through the network interface having the changed IP address based on the IP address change information (S611).

The application layer may set the data transmission amount and the transmission rate based on the available bandwidth in the path set in the SCTP transport layer (S613). The application layer may check the available bandwidth of the newly set path based on the path state information of the data link layer.

Accordingly, the SCTP connection of the present invention can prevent data transmission delay and packet packet loss by rapidly changing a network interface during congestion control using a cross-layer architecture.

Next, a method of performing an application layer function will be described with reference to FIGS. 4 and 7.

The data link layer collects path state information (S701).

The application layer may set a data transmission amount and a transmission rate on a specific path based on the path state information, in particular, the bandwidth (S703). The application layer may provide data to the SCTP transport layer according to the set data transmission rate and transmission rate.

The SCTP connection of the present invention can transmit data without transmission delay by using information of a lower layer at a faster time in an upper layer by a cross layer architecture.

8 is a diagram illustrating a data transmission method of a mesh network node using SCTP according to an embodiment of the present invention.

Hereinafter, for convenience, the first network interface 20 and the second network interface 30 in the plurality of network interfaces will be described as an example.

The transmitting node 10 connected to the receiving node 50 and the SCTP periodically transmits the heartbeat message 101, 103 to the receiving node 50 through the first and second network interfaces 20, 30, and receives the receiving node 50. Receive heartbeat ACKs 102 and 104 from 50. The transmitting node 10 analyzes whether the heartbeat ACKs 102 and 104 are received and the heartbeat ACKs 102 and 104 to collect path state information.

The transmitting node 10 sets the first network interface 20 as a network interface for the main path for transmitting data based on the path state information (105). The transmitting node 10 transmits data 106 to the receiving node 50 via the selected first network interface 20 and receives the ACK 107 from the receiving node 50. In addition, the transmitting node 10 periodically transmits the heartbeat message 103 to the receiving node 50 through the second network interface 30 of the auxiliary path that is in the idle state while transmitting the data 106 to the auxiliary path. Monitor periodically for availability.

When the transmitting node 10 detects a path failure in the main path (108), the transmitting node 10 sets the receiving node 50 and the second network interface 30 of the auxiliary path as the network interface for the main path. In this case, the connection information about the old route is automatically applied to the new route. Here, the path failure may include a network interface failure, a network failure, and a reduction in data rate due to congestion control. If the ACK for the data transmission is not received, it may be detected as a main path failure.

Specifically, when a path failure occurs during data transmission using the transmission path of data through the first network interface 20 as the main path (108), the path failure occurrence on the main path is detected by a path state detection operation at the data link layer. PATH FAIL ALAM (109).

The data link layer notifies 110 of the network interface change (i.e., route change) from the first network interface 20 to the second network interface 30 by forwarding the route change request information to the network layer. The data link layer change information includes data link layer connection establishment and termination, link up and link down information, and the like.

The network layer obtains the IP address of the second network interface 30 based on the path state information according to the path change request information, and transmits routing information including the IP address change to the SCTP transport layer (111).

The SCTP transport layer sets 112 the second network interface 30 as the network interface of the primary path.

The SCTP transport layer generates a SET-PRIMARY message 113 informing that the network interface of the main path has changed through the Stream Control Transport Protocol (SCTP), and transmits it to the receiving node 50. On the other hand, the first network interface 20 is a network interface of the auxiliary path.

The transmitting node 10 transmits data 114 to the receiving node 50 via the second network interface 30. In addition, the transmitting node 10 periodically transmits the heartbeat message 115 to the receiving node 50 through the first network interface 20 of the auxiliary path in the idle state while transmitting the data 114. Periodically monitor the path availability. When the auxiliary path using the first network interface 20 is restored, the transmitting node 10 may receive the heartbeat ACK 116 via the first network interface 20.

9 is a block diagram schematically illustrating an apparatus for transmitting and receiving data of a mesh network node using SCTP according to an embodiment of the present invention.

Referring to FIG. 9, mesh network nodes include first and second network interfaces NIC1 and NIC2, path state detection units 201 and 202, path selection unit 210, congestion control unit 221, and path setting unit ( 222, a rate setting unit 230, and a layer manager 240.

The mesh network node includes a plurality of network interfaces in the physical layer. Hereinafter, for convenience of description, the mesh network node will be described with the first network interface NIC1 as the primary path and the second network interface NIC2 as the secondary path.

The path state detector 201 of the data link layer monitors a real-time path through the first and second network interfaces NIC1 and NIC2 in the data link layer and collects path state information. The path state information includes a path ID, a bandwidth, a data rate, a data rate, and the like. The path state information is transmitted to the layer manager 240 and stored in the path state storage 250.

The path state detector 201 causes the mesh network node to perform a path change procedure when a failure is detected while transmitting data through the first network interface NIC1 of the main path. Here, the path failure may include a network interface failure, a network failure, and a reduction in data rate due to congestion control.

The path state detector 201 notifies the path selector 210 of the change from the first network interface NIC1 to the second network interface NIC2. The path state detection unit 201 may notify the network interface change and the path change request by transmitting data link layer connection establishment and termination, link up and link down information, and the like to the network layer.

The path selector 210 of the network layer reads and analyzes path state information according to a path change request, and then obtains an IP address of the second network interface NIC2. The route selecting unit 210 transmits IP address change information including the IP address of the second network interface NIC2 to the route setting unit 222.

The path setting unit 222 of the SCTP transport layer sets the main path and notifies the counterpart node of the change of the network interface of the main path. The route setting unit 222 sets the IP address of the second network interface NIC2 as the IP address of the main path based on the IP address change information. The route setting unit 222 generates a route change message SET-PRIMARY indicating that the network interface of the main route has been changed to the second network interface NIC2 and transmits it to the counterpart node.

The congestion control unit 221 of the SCTP transport layer performs congestion control based on the path state information to induce a change in the data transmission amount and the transmission rate of the path.

The transmission rate setting unit 230 of the application layer may set a transmission amount and a transmission rate of data to be transmitted through the network interface of the main path based on the path state information.

The layer manager 140 performs cross layer optimization to transfer data received from each layer to another layer so as to enable organic data exchange between layers, thereby mediating data transfer between layers. The path state storage unit 250 of the layer manager 140 stores a path ID, information on a network interface (network interface IP address, network interface status or network status), bandwidth, data transmission rate, and data transmission amount. .

10 is a flowchart illustrating a data transmission method between mesh network nodes using SCTP according to an embodiment of the present invention.

The transmitting node and the receiving node, which are mesh network nodes, are SCTP-connected and have one or more network interfaces, that is, multi-homed nodes, each of which is assigned an IP address. The network interface of the transmitting node and the network interface of the receiving node correspond one-to-one and each form a path.

Referring to FIG. 10, the transmitting node collects path state information of all paths existing between the receiving node in the data link layer (S801). The transmitting node periodically transmits the heartbeat message to the receiving node through the network interface of each path, and receives the heartbeat ACK from the receiving node. The transmitting node obtains path state information by analyzing whether the heartbeat ACK is received and the heartbeat ACK.

The transmitting node selects the network interface of the main path for transmitting data based on the path state information, and transmits data to the receiving node through the selected network interface (S803). The transmitting node analyzes whether the ACK is received and the ACK to obtain path state information.

When the transmitting node detects a path failure of the main path based on the path state information (S805), the transmitting node changes the network interface of the auxiliary path in the idle state to the network interface of the main path (S807). Path failures include network interface failures, network failures, and the like.

The transmitting node transmits data to the receiving node through the network interface of the newly set main path (S809). The transmitting node may detect a bandwidth based on path state information of the newly set main path, and determine a data transmission amount and a transmission rate based on the detected bandwidth. Meanwhile, the transmitting node may periodically transmit a heartbeat message to the receiving node through the network interface of the path where the path failure was detected, and receive a heartbeat ACK from the receiving node when the path failure is recovered.

11 is a flowchart illustrating a method of changing a data transmission path by a mesh network node using SCTP according to an embodiment of the present invention.

Referring to FIG. 11, when the transmitting node detects a path failure of the main path, the transmitting node changes the auxiliary path to the main path and transmits data to the receiving node without interruption.

When the path failure of the primary path is detected in the data link layer (S901), the data link layer performs an operation for changing the path from the primary path to the secondary path. Path failures include network interface failures, network failures, and the like. The path state information detected at the data link layer may be transmitted to the network layer, the SCTP transport layer, and the application layer by a cross layer architecture.

The data link layer notifies the network layer of the network interface change and requests a path change (S903).

The network layer obtains the changed network interface IP address based on the path state information according to the path change request, and notifies the SCTP transport layer of the network interface IP address change (S905).

The SCTP transport layer changes the network interface IP address of the main path and newly sets the main path (S907).

The SCTP transport layer sends a message SET-PRIMARY notifying the change of the network interface of the main path to the receiving node, and requests the main path change (S909).

For the purpose of understanding the present invention, reference numerals have been set forth in the preferred embodiments illustrated in the drawings, and specific terms are used to describe the embodiments, but the present invention is not limited to the specific terms, and the present invention It may include all components conventionally conceivable to those skilled in the art.

The invention can be represented by functional block configurations and various processing steps. Such functional blocks may be implemented in various numbers of hardware or / and software configurations that perform particular functions. For example, the present invention relates to integrated circuit configurations such as memory, processing, logic, look-up table, etc., which may execute various functions by the control of one or more microprocessors or other control devices. It can be adopted. Similar to the components of the present invention that may be implemented with software programming or software components, the present invention may be implemented as a combination of C, C ++, and C ++, including various algorithms implemented with data structures, processes, routines, , Java (Java), assembler, and the like. The functional aspects may be implemented with an algorithm running on one or more processors.

The specific acts described in the present invention are, by way of example, not intended to limit the scope of the invention in any way. For brevity of description, descriptions of conventional electronic configurations, control systems, software, and other functional aspects of such systems may be omitted. Also, the connections or connecting members of the lines between the components shown in the figures are illustrative of functional connections and / or physical or circuit connections, which may be replaced or additionally provided by a variety of functional connections, physical Connection, or circuit connections. In addition, unless otherwise specified, such as "essential", "important" may not be a necessary component for the application of the present invention.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

Claims (15)

In the data transmission method using the Stream Control Transmission Protocol (SCTP) of a mesh network node having a multi-network interface,
Detecting, by a transmitting node, a failure of the main path during data transmission to a receiving node through a first network interface of the main path transmitting data; And
And setting a new primary path by changing a first network interface of the primary path to a second network interface of a secondary path in an upper layer of the data link layer based on the path state information collected by the data link layer. Data transmission method using SCTP of a mesh network node. The method of claim 1, wherein the newly setting the main path comprises:
Transmitting a request for a path change from the primary path to the secondary path at a data link layer to a network layer;
Acquiring, by the network layer, an IP address of the second network interface based on the path state information and transmitting a network interface IP address change to a transport layer based on the path state information; And
And setting a new primary path by changing the first network interface IP address to the second network interface IP address in the transport layer. The method of claim 2, wherein the newly setting the main path comprises:
And notifying the receiving node of a major path change using the SCTP in the transport layer. The method of claim 1,
The path state information is a data transmission method using SCTP of a mesh network node including bandwidth, data rate and data rate. The method of claim 1,
And the transmitting node transmits a heartbeat message to the receiving node through a network interface of each auxiliary path to monitor the auxiliary path. The method of claim 1,
The path failure includes a network interface failure, a network failure, and a data transmission rate reduction due to congestion control. The method of claim 1,
The each layer is a data transmission method using the SCTP of the mesh network node for transmitting and receiving data to each other based on the cross layer. The method of claim 1,
And transmitting data to the receiving node through the second network interface. Multiple network interfaces;
A path state detection unit for collecting path state information through each network interface and detecting a failure of the main path during data transmission to a counterpart node through a first network interface of a main path for transmitting data;
A path selector configured to select a second network interface among network interfaces of an auxiliary path based on the path state information in a network layer; And
A path setting unit configured to set the second network interface as the main path in the transport layer, and notify the counterpart node of the main path change through the second network interface using a stream control transmission protocol (SCTP); Device for transmitting / receiving data of mesh network node using SCTP. 10. The method of claim 9,
And a layer manager configured to store the path state information and to transmit and receive data between layers based on a cross layer. The method of claim 9, wherein the path state detection unit,
An apparatus for transmitting / receiving data of a mesh network node using SCTP for transmitting a path change request due to the main path failure to a network layer. The method of claim 11, wherein the path selector,
The apparatus for transmitting / receiving data of a mesh network node using SCTP for acquiring an IP address of the second network interface and transmitting a network interface IP address change to the transport layer based on the path state information according to the path change request. The method of claim 12, wherein the path setting unit,
An apparatus for transmitting / receiving data of a mesh network node using SCTP by changing an IP address of the first network interface to an IP address of the second network interface to set a new main path. 10. The method of claim 9,
The mesh network node is a device for transmitting and receiving data of a mesh network node using SCTP including a mesh gateway, a mesh router, and a mesh client of a wireless mesh network. A mesh gateway connected to the wired network to exchange traffic of the mesh network with the wired backbone network through a backbone link;
A mesh router connected to the mesh gateway through a wireless mesh link; And
And a mesh client connected to the mesh router through a user link and transmitting and receiving data to and from an external server through the mesh router and the mesh gateway.
The mesh gateway, the mesh router, and the mesh client include a multi-network interface, transmit and receive data through the multi-network interface using a stream control transmission protocol (SCTP), and transmit data between layers based on a cross layer. Wireless mesh network system for transmitting and receiving.

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