WO2016153279A1

WO2016153279A1 - Method and device for searching for device in mesh network using bluetooth

Info

Publication number: WO2016153279A1
Application number: PCT/KR2016/002949
Authority: WO
Inventors: 최진구; 권영환; 임진권; 이현재; 이민수
Original assignee: 엘지전자(주)
Priority date: 2015-03-24
Filing date: 2016-03-23
Publication date: 2016-09-29

Abstract

Provided are a method and a device for obtaining, by a device, the information of the other devices, which form a mesh network, in a mesh network using Bluetooth. The method and the device according to the present invention enable: an advertisement message including at least one of configuration information of the mesh network and device information to be received from a second device; a connection request message to be transmitted to the second device on the basis of the advertisement message; and a Bluetooth LE connection with the second device, to be formed on the basis of the connection request message.

Description

Method and apparatus for discovering a device in a mesh network using Bluetooth

The present invention relates to a method and apparatus for discovering a device in a mesh network using Bluetooth, which is a near field technology, in a wireless communication system. will be.

Bluetooth is a short-range wireless technology standard that can transmit and receive data by wirelessly connecting various devices in a short distance. When performing wireless communication between two devices using Bluetooth communication, a user performs a procedure of searching for a Bluetooth device and requesting a connection. do. In the present invention, the device may mean an apparatus and an apparatus.

In this case, the user may perform a connection after searching for the Bluetooth device according to the Bluetooth communication method to use using the Bluetooth device.

The Bluetooth communication method includes a basic rate / enhanced data rate (BR / EDR) method and a low energy (LE) method, which is a low power method. The BR / EDR scheme may be referred to as Bluetooth Classic. The Bluetooth classic includes Bluetooth technology that has been adopted since Bluetooth 1.0 using Basic Rate and Bluetooth technology that has used Enhanced Data Rate supported since Bluetooth 2.0.

Bluetooth Low Energy (hereinafter referred to as Bluetooth LE) technology has been applied since Bluetooth 4.0, and can consume hundreds of kilobytes (KB) of information stably with low power consumption. The Bluetooth low energy energy technology uses an attribute protocol to exchange information between devices. This Bluetooth LE method can reduce energy overhead by reducing the header overhead and simplifying the operation.

Some Bluetooth devices do not have a display or a user interface. The complexity of connection / management / control / disconnection between various kinds of Bluetooth devices and similarly applied Bluetooth devices is increasing.

In addition, Bluetooth can achieve a relatively high speed at a relatively low power, low cost, but the transmission distance is generally limited to a maximum of 100m, it is suitable for use in a limited space.

It is an object of the present invention to provide a method for discovering a device using Bluetooth Low Energy (LE) technology.

Another object of the present invention is to provide a method for discovering a device outside a device search range in a Bluetooth mesh network.

Another object of the present invention is to provide a method for discovering a device forming a mesh network by receiving device information from a Bluetooth mesh network.

Another object of the present invention is to provide a method for discovering a device outside a device search range forming a mesh network by receiving device information from another device in a Bluetooth mesh network.

Another object of the present invention is to provide a method for searching before or after connecting a device outside a device discovery range forming a mesh network by receiving device information from another device in a Bluetooth mesh network.

The technical problems to be achieved in the present specification are not limited to the technical problems mentioned above, and other technical problems not mentioned above will be clearly understood by those skilled in the art from the following description. Could be.

The present invention provides a method for acquiring information of a device constituting a mesh network by a first device in a mesh network of Bluetooth for solving the above-described problem, comprising: configuration information or a device of the mesh network from a second device Receiving an advertising message including at least one of the information; Transmitting a connection request message to the second device based on the advertisement message; And establishing a Bluetooth LE connection with the second device based on the connection request message.

Also, in the present invention, the configuration information may include ID information indicating the mesh network, type information of devices constituting the mesh network, configuration purpose information, name information of the mesh network, or the number of devices constituting the mesh network. At least one of the information.

In the present invention, the device information includes at least one of name information, type information or ID information of a specific device constituting the mesh network.

The present invention may also include transmitting a scan request message for requesting additional information related to the configuration information or device information to the second device; And receiving a response message including the additional information in response to the scan request message.

In addition, in the present invention, the advertisement message further includes a flag indicating that the second device is a device obtaining configuration information or device information of the mesh network.

The present invention also provides a method comprising: transmitting a read request message requesting additional information related to the configuration information or device information to the second device; And receiving a read response message including the additional information in response to the read request message.

Also, in the present invention, the additional information may include ID information indicating the mesh network, type information of devices constituting the mesh network, configuration purpose information, name information of the mesh network, and information on the number of devices constituting the mesh network. And at least one of name information, type information, or ID information of a specific device constituting the mesh network.

The present invention also provides a method comprising: transmitting a request message for requesting network information related to a mesh network to a second device; Receiving a connection request message for establishing a Bluetooth LE connection to transmit the network information; Establishing a Bluetooth LE connection with the second device based on the connection request message; And receiving a response message including the network information from the second device, wherein the network information includes at least one of configuration information or device information of the mesh network.

In the present invention, the method may further include receiving an advertisement message including a part of the network information.

In addition, the present invention, the communication unit for communicating with the outside by wireless or wired; And

Including a processor that is functionally connected with the communication unit, The processor,

Receiving an advertisement message including at least one of configuration information or device information of the mesh network from a second device;

Transmit a connection request message to the second device based on the advertisement message;

A device for controlling to establish a Bluetooth LE connection with the second device based on the connection request message is provided.

According to the method for searching for a device in a mesh network of Bluetooth according to an embodiment of the present invention, a device forming a mesh network existing outside the search range of the device may be searched.

In addition, the present invention can search for a device forming a mesh network by receiving network information from a device having network information in a mesh network.

In addition, the present invention may search for a device that is outside the search range by receiving information of devices forming the mesh network before or after the connection from the device forming the mesh network.

In addition, the present invention may search for devices forming a mesh network and output the searched result through the device.

1 is a schematic diagram illustrating an example of a wireless communication system using a Bluetooth low power energy technology to which the present invention can be applied.

2 shows an example of an internal block diagram of a device to which the present invention can be applied.

3 shows an example of a Bluetooth low power energy topology.

4 is a diagram illustrating an example of a Bluetooth communication architecture to which the present invention can be applied.

5 is a diagram illustrating an example of a structure of a GATT (Generic Attribute Profile) based profile of Bluetooth low power energy.

6 is a diagram illustrating an example of a device-to-device connection procedure of Bluetooth low power energy.

7 is a schematic diagram illustrating an example of a Bluetooth mesh network to which the present invention may be applied.

8 is a diagram illustrating an example of a protocol stack of a Bluetooth mesh network to which the present invention can be applied.

9 is a flowchart illustrating an example of a method for a device to which the present invention may be applied to participate in a Bluetooth mesh network.

10 is a diagram illustrating an example of a method for discovering a device in a Bluetooth mesh network to which the present invention can be applied.

11 and 12 are diagrams illustrating an example of a method and a packet format for discovering a device in a Bluetooth mesh network to which the present invention can be applied.

13 to 16 illustrate another example of a method and a packet format for discovering a device in a Bluetooth mesh network to which the present invention can be applied.

17 and 18 are diagrams illustrating another example of a method and a packet format for discovering a device in a Bluetooth mesh network to which the present invention can be applied.

FIG. 19 is a diagram illustrating an example of a method of outputting a discovered device in a Bluetooth mesh network to which the present invention can be applied.

The above objects, features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. However, the present invention may be modified in various ways and may have various embodiments. Hereinafter, specific embodiments will be illustrated in the drawings and described in detail. Like numbers refer to like elements throughout. In addition, when it is determined that the detailed description of the known function or configuration related to the present invention may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

Hereinafter, a method and apparatus related to the present invention will be described in more detail with reference to the accompanying drawings. The suffixes "module" and "unit" for components used in the following description are given or used in consideration of ease of specification, and do not have distinct meanings or roles from each other.

The wireless communication system 100 includes at least one server device 120 and at least one client device 110.

The server device and the client device perform Bluetooth communication using Bluetooth Low Energy (BLE) technology.

First, compared to Bluetooth Basic Rate / Enhanced Data Rate (BR / EDR) technology, BLE technology has a relatively small duty cycle, enables low-cost production, and significantly reduces power consumption through low data rates. If you use a coin cell battery, it can operate for more than a year.

In addition, the BLE technology simplifies the connection procedure between devices, and the packet size is smaller than that of the Bluetooth BR / EDR technology.

In BLE technology, (1) the number of RF channels is 40, (2) the data rate supports 1Mbps, (3) the topology is a scatternet structure, (4) latency is 3ms, and (5) maximum current Is less than 15mA, (6) output power is less than 10mW (10dBm), and (7) is mainly used in applications such as mobile phones, watches, sports, healthcare, sensors, device control.

The server device 120 may operate as a client device in relation to other devices, and the client device may operate as a server device in relation to other devices. That is, in the BLE communication system, any one device may operate as a server device or a client device, and if necessary, operate as a server device and a client device.

The server device 120 may include a data service device, a slave device device, a slave, a server, a conductor, a host device, a gateway, and a sensing device. (Sensing Device), a monitoring device (monitoring device), the first device, the second device, etc., the client device 110 is a master device (master device), master (master), client, member (Member) ), A sensor device, a sink device, a collector, a control device, a first control device, a second control device, and the like.

The server device and the client device correspond to the main components of the wireless communication system, and the wireless communication system may include other components in addition to the server device and the client device.

When the server device receives data from the client device and directly communicates with the client device, and receives a data request from the client device, the server device provides the data to the client device through a response.

In addition, the server device sends a notification message and an indication message to the client device to provide data information to the client device. In addition, when the server apparatus transmits an instruction message to the client apparatus, the server apparatus receives a confirmation message corresponding to the instruction message from the client.

In addition, the server device provides data information to the user through a display unit or receives a request input from the user through a user input interface in the process of transmitting and receiving notification, instruction, and confirmation messages with the client device. can do.

In addition, the server device may read data from a memory unit or write new data to a corresponding memory in a process of transmitting and receiving a message with the client device.

In addition, one server device may be connected to a plurality of client devices, and may be easily reconnected (or connected) with client devices by using bonding information.

The client device 110 refers to a device that requests data information and data transmission from a server device.

The client device receives data from the server device through a notification message, an instruction message, and the like, and when receiving an instruction message from the server device, sends a confirmation message in response to the instruction message.

Similarly, the client device may provide information to the user through an output unit or receive an input from the user through an input unit in the process of transmitting and receiving messages with the server device.

In addition, the client device may read data from a memory or write new data to a corresponding memory in a process of transmitting and receiving a message with the server device.

Hardware components such as an output unit, an input unit, and a memory of the server device and the client device will be described in detail with reference to FIG. 2.

In addition, the wireless communication system may configure Personal Area Networking (PAN) through Bluetooth technology. For example, in the wireless communication system, by establishing a private piconet between devices, files, documents, and the like can be exchanged quickly and securely.

As illustrated in FIG. 2, the server device may include an output unit 111, a user input interface 112, a power supply unit 113, a processor 114, and a memory unit. , 115), a Bluetooth interface 116, another communication interface 117, and a communication unit (or a transceiver unit 118).

The output unit 111, the input unit 112, the power supply unit 113, the processor 114, the memory 115, the Bluetooth interface 116, the other communication interface 117 and the communication unit 118 are proposed herein. It is functionally linked to perform the method.

In addition, the client device may include a display unit 121, a user input interface 122, a power supply unit 123, a processor 124, a memory unit 125, and a Bluetooth interface. (Bluetooth Interface) 126 and a communication unit (or a transceiver unit 127).

The output unit 121, the input unit 122, the power supply unit 123, the processor 124, the memory 125, the Bluetooth interface 126, and the communication unit 127 are used to perform the method proposed in this specification. Functionally connected

The

Bluetooth interface

116, 126 refers to a unit (or module) capable of transmitting data or request / response, command, notification, indication / confirmation message, etc. between devices using Bluetooth technology.

The

memories

115 and 125 are units implemented in various types of devices and refer to units in which various kinds of data are stored.

The

processor

114, 124 refers to a module that controls the overall operation of the server device or the client device, and controls to process a message request and a received message through a Bluetooth interface and another communication interface.

The

processors

114 and 124 may be represented by a controller, a control unit, a controller, or the like.

The

processors

114 and 124 may include application-specific integrated circuits (ASICs), other chipsets, logic circuits, and / or data processing devices.

The

processor

114, 124 controls the communication unit to receive an advertising message from a server device, transmits a scan request message to the server device, and scans in response to the scan request from the server device. The communication unit controls the communication unit to receive a scan response message, and controls the communication unit to transmit a connect request message to the server device for establishing a Bluetooth connection with the server device.

The

processor

114 and 124 may also read or write data from the server device using a property protocol after a Bluetooth LE connection is formed through the connection procedure. To control.

The

memories

115 and 125 may include read-only memory (ROM), random access memory (RAM), flash memory, memory cards, storage media, and / or other storage devices.

The

communication unit

118 and 127 may include a baseband circuit for processing a radio signal. When the embodiment is implemented in software, the above-described technique may be implemented as a module (process, function, etc.) for performing the above-described function. The module may be stored in memory and executed by a processor.

The

memories

115 and 125 may be inside or outside the

processors

114 and 124, and may be connected to the

processors

114 and 124 by various well-known means.

The

output units

111 and 121 refer to modules for providing device status information and message exchange information to a user through a screen.

The power supply unit (power supply unit 113, 123) refers to a module for supplying power required for the operation of the components by receiving the external power, the internal power under the control of the controller.

As we saw earlier, BLE technology has a small duty cycle, and the low data rate can greatly reduce power consumption, so that the power supply is required for the operation of each component with less output power (10 mW (10 dBm or less)). Can supply power.

The

input units

112 and 122 refer to a module that provides a user's input to the controller like a screen button so that the user can control the operation of the device.

3 shows an example of a Bluetooth low power energy topology.

Referring to FIG. 3, device A corresponds to a master in a piconet (piconet A, shaded portion) having device B and device C as slaves.

Here, a piconet means a set of devices occupying a shared physical channel in which any one of a plurality of devices is a master and the remaining devices are connected to the master device.

The BLE slave does not share a common physical channel with the master and other slaves. That is, each slave communicates with the master through a separate physical channel. There is another piconet (piconet F) with master device F and slave device G.

Device K is on scatternet K. Here, a scatternet means a group of piconets in which connections between other piconets exist.

Device K is a master of device L and a slave of device M.

Device O is also on scatternet O. Device O is a slave of device P and a slave of device Q.

As shown in FIG. 2 above, there are five different device groups.

1. Device D is an advertiser and device A is an initiator (group D).

2. Device E is a scanner and device C is an advertiser (group C).

3. Device H is an advertiser and devices I and J are scanners (group H).

4. Device K is also an advertiser and device N is an initiator (group K).

5. Device R is the advertiser and device O is the initiator (group R).

Devices A and B use one BLE piconet physical channel.

Devices A and C use another BLE piconet physical channel.

In group D, device D advertises using an advertisement event connectable onto an advertising physical channel, and device A is an initiator. Device A may establish a connection with device D and add the device to piconet A.

In group C, device C advertises on the ad physical channel using some type of advertisement event captured by scanner device E.

Group D and Group C may use different advertising physical channels or use different times to avoid collisions.

Piconet F has one physical channel. Devices F and G use one BLE piconet physical channel. Device F is the master and device G is the slave.

Group H has one physical channel. Devices H, I and J use one BLE advertising physical channel. Device H is an advertiser and devices I and J are scanners.

In scatternet K, devices K and L use one BLE piconet physical channel. Devices K and M use another BLE piconet physical channel.

In group K, device K advertises using an advertisement event connectable onto an advertising physical channel, and device N is an initiator. Device N may form a connection with device K. Here, device K becomes a slave of two devices and simultaneously becomes a master of one device.

In scatternet O, devices O and P use one BLE piconet physical channel. Devices O and Q use another BLE piconet physical channel.

In group R, device R advertises using an advertisement event connectable onto an advertising physical channel, and device O is an initiator. Device O may form a connection with device R. Here, device O becomes a slave of two devices and simultaneously becomes a master of one device.

Referring to FIG. 4, (a) of FIG. 4 shows an example of a protocol stack of Bluetooth Basic Rate (BR) / Enhanced Data Rate (EDR), and (b) shows a protocol stack of Bluetooth Low Energy (LE). An example is shown.

Specifically, as shown in FIG. 4A, the Bluetooth BR / EDR protocol stack has an upper controller stack 10 and a lower controller stack based on a host controller interface (HCI) 18. It may include a host stack (20) of.

The host stack (or host module) 20 refers to a wireless transceiver module for receiving a 2.4 GHz Bluetooth signal and hardware for transmitting or receiving a Bluetooth packet. The host stack (or host module) 20 is connected to a Bluetooth module which is the controller stack 10 to connect a Bluetooth module. Control and perform actions.

The host stack 20 may include a BR / EDR PHY layer 12, a BR / EDR baseband layer 14, and a link manager layer 16.

The BR / EDR PHY layer 12 is a layer for transmitting / receiving a 2.4 GHz radio signal and may transmit data by hopping 79 RF channels when using Gaussian Frequency Shift Keying (GFSK) modulation.

The BR / EDR baseband layer 14 plays a role of transmitting a digital signal, selects a channel sequence hopping 1400 times per second, and transmits a 625us length time slot for each channel.

The link manager layer 16 controls the overall operation (link setup, control, security) of the Bluetooth connection by using a link manager protocol (LMP).

The link manager layer 16 may perform the following functions.

ACL / SCO logical transport, logical link setup and control

Detach: Stops the connection and tells the other device why.

-Perform power control and role switch.

-Perform Security (authentication, pairing, encryption) function.

The host controller interface layer 18 provides an interface between the host module and the controller module so that the host can provide commands and data to the controller, and the controller can provide events and data to the host.

The host stack (or host module) 20 may include a logical link control and adaptation protocol (L2CAP, 21), an attribute protocol (Protocol, 22), a generic attribute profile (GATT, 23), and a generic access profile. Profile, GAP, 24), BR / EDR profile 25.

The logical link control and adaptation protocol (L2CAP) 21 may provide one bidirectional channel for transmitting data to a specific protocol or profile.

The L2CAP 21 may multiplex various protocols, profiles, etc. provided by a higher layer of Bluetooth.

L2CAP of Bluetooth BR / EDR uses dynamic channel, supports protocol service multiplexer, retransmission, streaming mode, and provides segmentation, reassembly, per-channel flow control, and error control.

The generic attribute profile (GATT) 23 may be operable as a protocol describing how the attribute protocol 22 is used in the construction of services. For example, the general attribute profile 23 may be operable to specify how ATT attributes are grouped together into services, and may be operable to describe features associated with the services.

Thus, the generic attribute profile 23 and the attribute protocol ATT 22 may use features to describe the state and services of a device and to describe how features relate to each other and how they are used.

The attribute protocol 22 and the BR / EDR profile 25 define a service (or profile) using Bluet's BR / EDR and an application protocol for sending and receiving these data, and the Generic Access Profile , GAP, 24) define how devices are discovered, connected, and informed, and provide privacy.

As shown in FIG. 4B, the Bluetooth LE protocol stack is a controller stack 30 operable to handle timing-critical radio interface and a host operable to process high level data. It contains a stack (Host stack, 40).

First, the controller stack 30 may be implemented using a communication module that may include a Bluetooth radio, for example, a processor module that may include a processing device such as a microprocessor.

The host stack may be implemented as part of an OS running on a processor module, or as an instance of a package on the OS.

In some instances, the controller stack and the host stack can be operated or executed on the same processing device in the processor module.

The controller stack 30 includes a physical layer (PHY) 32, a link layer 34, and a host controller interface 36.

The physical layer (PHY) 32 is a layer that transmits and receives a 2.4 GHz radio signal and uses GFSK (Gaussian Frequency Shift Keying) modulation and a frequency hopping technique composed of 40 RF channels.

The link layer 34, which transmits or receives a Bluetooth packet, creates a connection between devices after performing advertising and scanning functions using three advertising channels, and generates up to 257 bytes of data packets through 37 data channels. Provides the ability to send and receive.

The host stack includes a generic access profile (GAP) 40, a logical link control and adaptation protocol (L2CAP, 41), a security manager (SM, 42), an attribute protocol (ATT, 440), and a general attribute profile. (Generic Attribute Profile, GATT, 44), Generic Access Profile (25), LE profile (46) may be included. However, the host stack 40 is not limited to this and may include various protocols and profiles.

The host stack uses L2CAP to multiplex the various protocols, profiles, etc. provided by Bluetooth.

First, L2CAP (Logical Link Control and Adaptation Protocol) 41 may provide one bidirectional channel for transmitting data to a specific protocol or profile.

The L2CAP 41 may be operable to multiplex data among higher layer protocols, segment and reassemble packages, and manage multicast data transmission.

Bluetooth LE uses three fixed channels (one for the signaling channel, one for the Security Manager, and one for the Attribute protocol).

On the other hand, BR / EDR (Basic Rate / Enhanced Data Rate) uses dynamic channels and supports protocol service multiplexer, retransmission, and streaming mode.

The SM (Security Manager) 42 is a protocol for authenticating a device and providing key distribution.

Attribute Protocol (ATT) 43 defines a rule for accessing data of a counterpart device in a server-client structure. ATT has six message types (Request, Response, Command, Notification, Indication, Confirmation).

① Request and Response message: The Request message is a message for requesting specific information from the client device to the server device, and the Response message is a response message to the request message, which is a message transmitted from the server device to the client device.

② Command message: A message sent from the client device to the server device to indicate a command of a specific operation. The server device does not transmit a response to the command message to the client device.

③ Notification message: This message is sent from the server device to the client device for notification such as an event. The client device does not transmit a confirmation message for the notification message to the server device.

④ Indication and Confirm message: This message is transmitted from the server device to the client device for notification such as an event. Unlike the notification message, the client device transmits a confirmation message for the Indication message to the server device.

The present invention transmits a value for the data length when a long data request is made in the GATT profile using the attribute protocol (ATT, 43) so that the client can know the data length clearly, and from the server using the UUID (Characteristic) Can receive the value.

The General Access Profile (GAP) 45 is a newly implemented layer for Bluetooth LE technology, and is used to control role selection and multi-profile operation for communication between Bluetooth LE devices.

In addition, the general access profile 45 is mainly used for device discovery, connection creation, and security procedures, and defines a method of providing information to a user, and defines the type of an attribute as follows.

① Service: Defines the basic behavior of the device with a combination of behaviors related to data.

② Include: Define the relationship between services

③ Characteristics: data value used in service

Behavior: A computer readable format defined by UUID (Universal Unique Identifier, value type).

The LE profile 46 is mainly applied to a Bluetooth LE device as profiles having a dependency on GATT. The LE profile 46 may be, for example, Battery, Time, FindMe, Proximity, Time, Object Delivery Service, and the like. Details of GATT-based Profiles are as follows.

① Battery: How to exchange battery information

② Time: How to exchange time information

③ FindMe: Provides alarm service according to distance

④ Proximity: How to exchange battery information

⑤ Time: How to exchange time information

The generic attribute profile GATT 44 may be operable as a protocol describing how the attribute protocol 43 is used in the construction of services. For example, the generic attribute profile 44 may be operable to specify how ATT attributes are grouped together into services, and may be operable to describe features associated with the services.

Thus, the generic attribute profile 44 and the attribute protocol (ATT, 43) may use features to describe the state and services of a device, and how features relate to each other and how they are used.

In the following, the procedure of the Bluetooth Low Energy (BLE) technology will be briefly described.

The BLE procedure may be classified into a device filtering procedure, an advertising procedure, a scanning procedure, a discovery procedure, a connecting procedure, and the like.

디바이스device 필터링Filter 절차(Device Filtering Procedure) Device Filtering Procedure

The device filtering procedure is a method for reducing the number of devices performing a response to a request, an indication, a notification, and the like in the controller stack.

When all devices receive a request, it is unnecessary to respond to it, so the controller stack can control the number of requests sent, reducing power consumption in the BLE controller stack.

The advertising device or scanning device may perform the device filtering procedure to limit the device receiving the advertising packet, scan request or connection request.

Here, the advertising device refers to a device that transmits an advertising event, that is, performs an advertisement, and is also referred to as an advertiser.

The scanning device refers to a device that performs scanning and a device that transmits a scan request.

In BLE, when the scanning device receives some advertising packets from the advertising device, the scanning device should send a scan request to the advertising device.

However, if a device filtering procedure is used so that a scan request transmission is unnecessary, the scanning device may ignore the advertisement packets transmitted from the advertisement device.

The device filtering procedure may also be used in the connection request process. If device filtering is used in the connection request process, it is not necessary to transmit a response to the connection request by ignoring the connection request.

광고 절차(Advertising Procedure)Advertising Procedure

The advertising device performs an advertising procedure to perform a non-directional broadcast to the devices in the area.

Here, undirected advertising is advertising directed to all (all) devices, not broadcast to a specific device, and all devices scan advertising to request additional information. You can make a connection request.

On the contrary, in the directed advertising, only the device designated as the receiving device can scan an advertising and request an additional information or a connection request.

The advertising procedure is used to establish a Bluetooth connection with a nearby initiating device.

Alternatively, the advertising procedure may be used to provide periodic broadcast of user data to the scanning devices that are listening on the advertising channel.

In the advertising process, all advertisements (or advertisement events) are broadcast over an advertising physical channel.

The advertising devices may receive a scan request from listening devices that are listening to obtain additional user data from the advertising device. The advertising device transmits a response to the scan request to the device that sent the scan request through the same advertising physical channel as the received advertising physical channel.

Broadcast user data sent as part of an advertisement packet is dynamic data, while scan response data is generally static data.

The advertising device may receive a connection request from the initiating device on the advertising (broadcast) physical channel. If the advertising device used a connectable advertising event and the initiating device was not filtered by the device filtering procedure, the advertising device stops the advertising and enters the connected mode. The advertising device may start advertising again after the connected mode.

스캐닝 절차(Scanning Procedure)Scanning Procedure

The device performing the scanning, i.e., the scanning device, performs a scanning procedure to listen to the non-directional broadcast of the user data from the advertising devices using the advertising physical channel.

The scanning device sends a scan request to the advertising device via the advertising physical channel to request additional user data from the advertising device. The advertising device transmits a scan response that is a response to the scan request, including additional user data requested by the scanning device over the advertising physical channel.

The scanning procedure can be used while connected to other BLE devices in the BLE piconet.

If the scanning device is in an initiator mode that can receive the broadcasted advertising event and initiate a connection request, the scanning device sends the connection request to the advertising device via the advertising physical channel to the advertising device. You can start a Bluetooth connection with.

When the scanning device sends a connection request to the advertising device, the scanning device stops initiator mode scanning for further broadcast and enters the connected mode.

디스커버링Discovery 절차(Discovering Procedure) Discovery Procedure

Devices capable of Bluetooth communication (hereinafter referred to as "Bluetooth devices") perform an advertisement procedure and a scanning procedure to find devices that are nearby or to be found by other devices within a given area.

The discovery procedure is performed asymmetrically. A Bluetooth device that attempts to find another device around it is called a discovering device and listens for devices that advertise a scannable advertisement event. Bluetooth devices discovered and available from other devices are referred to as discoverable devices, and actively broadcast advertising events so that other devices can scan through an advertising (broadcast) physical channel.

Both the discovering device and the discoverable device may already be connected with other Bluetooth devices in the piconet.

연결 절차(Connecting Procedure)Connecting Procedure

The connection procedure is asymmetric, and the connection procedure requires the other Bluetooth device to perform the scanning procedure while the specific Bluetooth device performs the advertisement procedure.

That is, the advertising procedure can be the goal, so that only one device will respond to the advertising. After receiving the accessible advertising event from the advertising device, the connection may be initiated by sending a connection request to the advertising device via the advertising (broadcast) physical channel.

Next, an operation state of the BLE technology, that is, an advertising state, a scanning state, an initiating state, and a connection state will be briefly described.

광고 상태(Advertising State)Advertising State

The link layer LL enters the advertisement state by the instruction of the host (stack). If the link layer is in the advertisement state, the link layer sends advertisement packet data units (PDUs) in the advertisement events.

Each advertising event consists of at least one advertising PDU, which is transmitted via the advertising channel indexes used. The advertisement event may terminate when the advertisement PDU is transmitted through each of the advertisement channel indexes used, or may terminate the advertisement event earlier when the advertisement device needs to make space for performing another function.

스캐닝 상태(Scanning State)Scanning State

The link layer enters the scanning state by the indication of the host (stack). In the scanning state, the link layer listens for advertising channel indices.

There are two types of scanning states: passive scanning and active scanning, each scanning type being determined by the host.

There is no separate time or advertisement channel index for performing scanning.

During the scanning state, the link layer listens for the advertising channel index during the scanWindow duration. ScanInterval is defined as the interval (interval) between the starting points of two consecutive scan windows.

If there is no scheduling conflict, the link layer must listen for completion of all scan intervals in the scan window as instructed by the host. In each scan window, the link layer must scan a different advertising channel index. The link layer uses all available advertising channel indexes.

When passive scanning, the link layer only receives packets and does not transmit any packets.

When active scanning, the link layer performs listening to rely on the advertising PDU type, which may request advertising PDUs and additional information related to the advertising device from the advertising device.

개시 상태(Initiating State)Initiating State

The link layer enters the initiation state by the indication of the host (stack).

When the link layer is in the initiating state, the link layer performs listening for the advertising channel indexes.

During the initiation state, the link layer listens for the advertising channel index during the scan window period.

연결 상태(connection state)Connection state

The link layer enters the connected state when the device performing the connection request, i.e., the initiating device, sends the CONNECT_REQ PDU to the advertising device or when the advertising device receives the CONNECT_REQ PDU from the initiating device.

After entering the connected state, the connection is considered to be created. However, it does not need to be considered to be established at the time the connection enters the connected state. The only difference between the newly created connection and the established connection is the link layer connection supervision timeout value.

When two devices are connected, the two devices act in different roles.

The link layer that performs the master role is called a master, and the link layer that performs the slave role is called a slave. The master controls the timing of the connection event, and the connection event is the point in time when the master and the slave are synchronized.

Hereinafter, the packet defined in the Bluetooth interface will be briefly described. BLE devices use the packets defined below.

패킷 포맷(Packet Format)Packet Format

The link layer has only one packet format used for both advertisement channel packets and data channel packets.

Each packet consists of four fields: Preamble, Access Address, PDU, and CRC.

When one packet is sent on an advertising physical channel, the PDU will be an advertising channel PDU, and when one packet is sent on a data physical channel, the PDU will be a data channel PDU.

광고 채널 Advertising channel PDUPDU (Advertising Channel (Advertising Channel PDUPDU ))

The advertising channel PDU (Packet Data Unit) has a 16-bit header and payloads of various sizes.

The PDU type field of the advertising channel PDU included in the header indicates a PDU type as defined in Table 1 below.

광고 Advertising PDUPDU (Advertising (Advertising PDUPDU ))

The following advertising channel PDU types are called advertising PDUs and are used in specific events.

ADV_IND: Connectable Non-Oriented Ads Event

ADV_DIRECT_IND: Connectable Directional Advertising Event

ADV_NONCONN_IND: Non-Connectable Non-Oriented Ads Event

ADV_SCAN_IND: Scannable Non-Oriented Ads Event

The PDUs are transmitted at the link layer in the advertisement state and received by the link layer in the scanning state or initiating state.

스캐닝 scanning PDUPDU (Scanning (Scanning PDUPDU ))

The advertising channel PDU type below is called a scanning PDU and is used in the state described below.

SCAN_REQ: Sent by the link layer in the scanning state and received by the link layer in the advertising state.

SCAN_RSP: Sent by the link layer in the advertising state and received by the link layer in the scanning state.

개시 Start PDUPDU (Initiating (Initiating PDUPDU ))

The advertising channel PDU type below is called the initiating PDU.

CONNECT_REQ: Sent by the link layer in the initiating state and received by the link layer in the advertising state.

데이터 채널 Data channel PDUPDU (Data Channel (Data Channel PDUPDU ))

The data channel PDU has a 16-bit header, payloads of various sizes, and may include a message integrity check (MIC) field.

As described above, the procedure, state, packet format, etc. in the BLE technology may be applied to perform the methods proposed herein.

Referring to FIG. 5, a structure for exchanging profile data of Bluetooth low power energy may be described.

In detail, the GATT (Generic Attribute Profile) defines a method of exchanging data using services and characteristics between Bluetooth LE devices.

In general, a peripheral device (for example, a sensor device) serves as a GATT server, and has a definition of a service and a characteristic.

To read or write data, the GATT client sends a data request to the GATT server, and all transactions begin at the GATT client and receive a response from the GATT server.

The GATT-based operating structure used in the Bluetooth LE is based on Profile, Service, and Characteristic, and may form a vertical structure as shown in FIG. 5.

The profile consists of one or more services, and the service may consist of one or more features or other services.

The service divides data into logical units and may include one or more characteristics or other services. Each service has a 16-bit or 128-bit identifier called the Universal Unique Identifier (UUID).

The characteristic is the lowest unit in the GATT based operation structure. The property contains only one data and has a UUID of 16 bits or 128 bits similar to the service.

The property is defined as a value of various pieces of information and requires one attribute to contain each piece of information. Multiple properties of the above properties can be used.

The attribute consists of four components and has the following meaning.

handle: the address of the property

Type: the type of the attribute

Value: the value of the property

Permission: permission to the property

However, Bluetooth LE has a variable link quality due to the characteristics of wireless transmission, and may cause a shadow area exceeding the radio propagation distance due to the one-to-one connection characteristic. Therefore, in order to solve such a problem, Bluetooth can form a mesh network with devices equipped with Bluetooth as a method for controlling a multi-hop connection between multiple devices.

6 is a flowchart illustrating an example of a device-to-device connection procedure of Bluetooth low power energy.

As shown in FIG. 6, the server device 110 transmits an advertising message to the client device 120 for a Bluetooth LE connection between the server device 110 and the client device 120 ( S6010).

As described above, the advertisement message is used to provide its own information to other devices using Bluetooth LE, and may include various information such as service information and user information provided by the device.

After checking the information included in the advertisement message transmitted from the server device 110, the client device 120 may transmit a scan request message to the server device when additional information about the server device is needed ( S6020).

When the server device 110 receives the scan request message from the client, the server device 110 includes the requested additional information in the scan response message and transmits it to the client device 120 (S6030).

The step S6020 and the step S6030 are optional steps and are not essential steps.

When the server device 110 is a device to which the client device 120 is to be connected, based on the information included in the advertisement message and / or the scan response message transmitted from the server device, the server device 110 The connection request message for the connection is transmitted (S6040).

Thereafter, the server device 110 and the client device 120 form a Bluetooth Low Energy (LE) connection (S6030).

This procedure allows Bluetooth devices to form a Bluetooth LE connection.

Hereinafter, the mesh network will be described.

As shown in FIG. 7, the mesh network refers to a network in which a plurality of devices are connected like a network through Bluetooth to transmit and receive data.

The Bluetooth mesh network technology includes one or more devices for relaying (or relaying) a message between a source device 200-1 transmitting data and a destination device 200-2 receiving data.

In this case, the source device and the destination device may be referred to as edge nodes 200-1 and 200-2, and one or more devices relaying messages in the middle may relay relay messages. ) May be called.

Alternatively, the device may be configured as a device whose position is easily changed, that is, a device 200-1 and 200-2 having mobility and fixed devices without mobility in an initially installed state.

Each relay node contains a message cache of recently received messages. If the received message already exists in the message cache, the message is not relayed.

However, if the received message is not in the message cache, the message is relayed and the message is stored in the message cache.

Edge nodes are usually powered by a battery and can normally sleep and then wake up or interact periodically.

The edge node can process the received message if the following conditions are met.

-The message does not exist in the message cache.

The message is authenticated by a known network key.

The destination of the message is the unicast address of the edge node, or the broadcast address or group address is the address to which the edge node belongs.

Relay nodes are usually mains powered devices that are always awake and can transmit data they receive for other nodes.

The relay node may retransmit the received message to another node if the following conditions are met.

-The message does not exist in the message cache.

The message is authenticated by a known network key.

A field indicating whether or not the message is relayed (e.g., relay count value) is a value that allows relaying.

The destination address is not a unicast address assigned to the relay node.

In the Bluetooth mesh network, the data may be classified into a floating method and a routing method according to a data transmission method of the relay nodes 200-3 and 200-4.

The floating method refers to a method in which relay nodes receiving a message shoot the air again in the air by using a property in which radio waves spread in all directions in the air.

That is, the source device 200-1 transmits a message to the relay nodes 200-3 and 200-4 through broadcast channels, and the relay nodes receiving the message transmit the message to neighboring relay nodes again. The transmission method to the destination device 200-2.

In the floating scheme, a broadcasting channel is used to receive and retransmit a message, and the transmission range of the message can be extended.

The mesh network of the floating scheme is a dynamic network, and in the floating mesh network, a device may be able to receive and transmit (or retransmit) a message at any time as long as the device's density is satisfied.

Although the floating scheme has an advantage of being easy to implement, since a message is transmitted without direction, scalability problems may occur as the network expands.

That is, in the floating mesh network, when a device transmits a message, a plurality of devices receive the message and transmit the received message to another plurality of devices.

To prevent this, the number of devices constituting the mesh network can be adjusted between 100 and 1000, and the exact number of devices can be determined by various factors.

For example, it may be determined by network capacity, traffic load of data sources, network latency and reliability requirements, and the like.

In addition, unlike the routing method, the floating method can easily deliver a message without the cost of establishing a routing table. However, the floating method increases network traffic due to the retransmission of the received message. exist.

In the routing scheme, the source device 200-1 transmits a message to a specific relay node, and the specific relay node which has received the message has information of another relay node or destination node 200-2 to resend the message. Will be sent.

The routing method uses a broadcasting channel or a point-to-point connection method for receiving and retransmitting a message.

In addition, in the routing scheme, the routing device receiving the message determines the best routing route (s) for sending the message to an intermediate device or a destination device, and to which route to send the message based on the determined routing table. Determine whether or not.

The routing scheme has the advantage of scalability, but since each node has to maintain a routing table and transmit a message, the complexity increases as the message increases, requires more memory, and is less than the floating scheme. The disadvantage is that it is dynamic and more difficult to implement.

Referring to FIG. 8, the protocol stack of the mesh network includes a bearer layer 81, a network layer 82, a transport layer 83, and an application layer 84.

The bearer layer 81 defines how messages are transmitted between nodes. That is, it determines the bearer to which the message is transmitted in the mesh network.

In a mesh network, there are an advertising bearer and a GATT bearer for transmitting a message.

The network layer 82 defines how a message is sent to one or more nodes in a mesh network and the format of network messages transmitted by the bearer layer 81.

The network layer 82 also defines whether the message is to be relayed or forwarded and how to authenticate and encrypt network messages.

The transport layer 83 provides the confidentiality of application messages to define the encryption and authentication of application data.

The application layer 84 defines a method, an application operation code and parameters related to how the upper layer application uses the transport layer 73.

A new device or a non-provisioned device must go through a provisioning procedure in order to join and operate in the mesh network.

The provisioning procedure refers to a procedure for authenticating an unauthenticated device and providing basic information (eg, a unicast address, various keys, etc.) for participating in a mesh network.

That is, the provisioning procedure is a procedure for providing a provisioner (second device 400) of the mesh network to participate in the mesh network, the first device 300 is a network through the provisioning procedure The address, keys, device identifier and various information for operating as part of the mesh network can be obtained.

The provisioning procedure is composed of an invitation step, an exchanging public key step, an authentication step, and a provisioning data distribution step.

The provisioning procedure may be performed through various kinds of bearers. For example, it may be performed by an advertising-based bearer, a mesh provisioning service-based bearer, or a mesh-based bearer.

The bearer based on the advertisement is a bearer that is essentially established and does not support the bearer based on the advertisement, or the bearer based on the provisioning service or the mesh based bearer when the provisioning data cannot be transmitted through the bearer based on the advertisement. It can be used for provisioning procedures.

The bearer based on the provisioning service means a bearer for exchanging and receiving provisioning data through the GATT Protocol of the existing Bluetooth LE, and the bearer based on the mesh is directly connected by the first device 300 and the second device 400. If there is no distance to send and receive data, it means a bearer that can send and receive provisioning data through a mesh network.

The procedure of establishing a bearer based on the advertisement will be described later.

After the bearer is established between the first device 300 and the second device 400, the first device 300 may be provisioned through the following provisioning procedure.

초대 단계(Invitation Step)Invitation Step

The inviting step begins with the second device 400 scanning the first device 300. The first device transmits a beacon message to the second device 400 (S9010). The beacon message includes the UUID of the first device 300.

The second device 400 scanning the first device 300 through the beacon message transmits an invitation message to the first device 300 (S9020).

The invitation message asks whether the first device 300 performs a provisioning procedure. If the first device 300 does not want the first device 300 to perform the provisioning procedure, the invitation message is ignored.

However, when the first device 300 wants to perform the provisioning procedure, that is, when it wants to participate in the mesh network, the first device 300 transmits a capability message in response thereto. (S9030).

The capability message includes information indicating whether the first device 300 supports setting of a security algorithm, a public key, information indicating whether a value can be output to a user, and whether a value can be input from the user. It may include information indicating the.

공용 키Public key 교환 단계(Exchanging Public Key Step) Exchange Public Key Step

Thereafter, the second device 400 transmits a start message for starting provisioning to the first device 300 (S9040).

If the public key is not available using an out of band technology, the second device 400 and the first device 300 exchange public keys (S9050, S9060).

However, when the public key is available through the out-of-band mechanism, the second device 400 transmits an epoxy public key to the first device 300 and the first device 300. Static public keys can be read from using out-of-band technology.

Thereafter, the second device 400 authenticates the first device 300 by performing an authentication procedure with the first device 300 (S9070).

프로비저닝Provisioning 데이터 배포 단계(Distribution of Provisioning Data Step) Distribution of Provisioning Data Step

When the first device 300 is authenticated, the second device 400 and the first device 300 calculates and generates a session key.

Thereafter, the second device 400 transmits provisioning data to the first device 300 (S9080).

The provisioning data may include an application key, a device key, a network key, an IVindex, a unicast address, and the like.

Upon receiving the provisioning data, the first device 300 transmits a completion message in response to the provisioning data, and the provisioning procedure is terminated (S9090).

The Bluetooth mesh network may be composed of a stationary device and a mobile device having a high mobility because there is little or no mobility.

An example of the non-flowable device may be devices that are fixed due to lack of mobility in an initially installed state such as a light device such as a light bulb, a TV, a switch, or the like.

An example of the mobile device may be a mobile terminal.

In FIG. 10, nine non-flowing devices S1 to S9 form a Bluetooth mesh network. The S1 to S9 may transmit and receive a message through the above-described floating technique or routing technique.

In this case, when the device 1 400, which is a mobile device, wants to search for a mesh network that exists around the device 1 400, the device 1 400 searches for nearby devices using various methods.

For example, the device 1 400 scans an advertisement message transmitted by at least one of the devices S1 to S9, or establishes a Bluetooth LE connection with one of the devices S1 to S9 to obtain information of the mesh network. Can be obtained.

However, as shown in FIG. 10, the search range of the first device 400 is limited so that the first device 400 may search only S2, S3, and S5 included in the search range. There is a problem that it is difficult to obtain information on the entire mesh network consisting of S1 to S9.

Accordingly, in order to solve this problem, the present invention provides a method for the first device 400 to obtain information about the entire mesh network through S2, S3, or S5 within a search range.

For example, each device forming the mesh network has information related to the mesh network, and the first device 400 obtains the information related to the mesh network by obtaining the information from the device forming the mesh network. It provides a method for doing so.

Referring to FIGS. 11 and 12, the mobile device searches for all devices constituting the mesh network by receiving information related to the mesh network without establishing a Bluetooth LE connection with the device forming the mesh network. Can be.

First, it is assumed that at least one device forming the mesh network has information of all devices forming the mesh network.

In detail, the second device 500 constituting the mesh network may transmit an advertisement message including network information of the mesh network to neighboring devices in the advertisement state (S11010).

In this case, the second device may be a non-fluid device as described above, and the advertisement message may be periodically transmitted through a broadcast method.

The advertisement message may be configured in the packet format as shown in FIG. 12, wherein the AD Type field indicates the type of network information included and the AD Data field includes a specific value corresponding to the AD type.

Table 2 below shows an example of AD Type and AD Data that may be included in the advertisement message.

The network information may include configuration information including information related to the configuration of the mesh network and device information related to each device forming the mesh network.

In Table 2, "Mesh ID", "Mesh Type", "Mesh Purpose" and "Mesh Name" may be included in the configuration information, and the "Member device ID", "Member device name" and "Member device type". May be included in the device information.

The first device 400 receiving the network information may search for all devices forming the mesh network through the network information.

However, if it is impossible to search all devices forming the mesh network using only the network information included in the advertisement message, for example, when only some information is transmitted due to the packet size limitation of the advertisement message, The first device 400 may transmit a scan request message requesting additional information to the second device 500 (S11020).

The second device 500 may transmit a response message including the additional information to the first device 400 in response to the scan request message.

In this case, the additional information may include network information not included in the advertisement message.

Upon receiving the response message, the first device 400 may search for all devices forming the mesh network, and transmit the specific information to the discovered device or transmit a control message indicating a specific operation. You can control the device.

13 to 16, the mobile device establishes a Bluetooth LE connection with a device forming a mesh network, and receives information related to the mesh network to search for all devices forming the mesh network. have.

In detail, the second device 500 transmits an advertisement message including the information of the second device 500 to the first device 400 (S13010).

In this case, the advertisement message may include a flag indicating that the second device 500 has information of all devices forming the mesh network.

Upon receiving the advertisement message, the first device 400 can discover the second device 500 and know that the second device 500 has information of all devices forming the mesh network. Can be.

Thereafter, as shown in FIG. 6, the first device 400 transmits a connection request message to form a Bluetooth LE connection with the second device 500 (S13020), and performs an authentication procedure and a security procedure. A Bluetooth LE connection may be formed with the second device 500 (S13030).

The first device 400, which has established a Bluetooth LE connection with the second device 500, reads a read request message to request network information related to the mesh network stored in the GATT data base of the second device 500. Read Request message) is transmitted (13040).

Upon receiving the read request message, the second device 500 transmits a read response message including network information stored in a GATT database to the first device 400 (S13050).

14 illustrates an example of network information stored in a GATT data base of the second device, and FIG. 16 illustrates an example of the read response message.

As illustrated in FIG. 14, the network information may include configuration information including information related to the configuration of the mesh network and device information related to each device forming the mesh network.

The configuration information may include “Mesh ID”, “Mesh Type”, “Mesh Purpose” “Mesh Name”, and “Number of Member device”, and the device information includes “Member device ID” and “Member device name”. And “Member device type”.

As illustrated in FIG. 15, the response message may include a “Length” field, a “Channel ID” field, and an “Information Payload”.

At this time, if the "Channel ID" field is set to "0x0004", it indicates that the format of the "Information Payload field" is configured as an Attribute Structure as shown in FIG. 15 to transmit and receive messages using the Attribute Protocol.

The “Attribute Type” field indicates a type of information as in the Characteristic name of FIG. 15, and the “Attribute Value” field includes a specific value corresponding to the attribute type.

The first device 400 discovers all devices constituting the mesh network through the read response message, and transmits or receives a message with devices constituting the mesh network or instructs a specific device to perform a specific operation. You can send a message to control the discovered device.

FIG. 16 illustrates an example of a packet type for transmitting and receiving data to and from a device in which the first device 400 configures a mesh network.

FIG. 16A illustrates an example of a packet for transmitting / receiving data to and from a device forming a mesh network when the first device 400 is not joined to or wants to join the mesh network. Indicates.

In this case, the “Device UUID” field may include a device ID value used in the mesh network.

FIG. 16B illustrates an example of a packet for transmitting and receiving data to and from a device forming a mesh network when the first device 400 joins the mesh network through the procedure described with reference to FIG. 9. .

In this case, the “CIVI” field may include an IV index value currently used in the mesh network.

FIG. 16C illustrates an example of a packet for controlling a specific device forming a mesh network when the first device 400 joins the mesh network through the procedure described with reference to FIG. 9.

A description of the value included in each field of FIG. 16 is as follows.

IVI: The value of the IV index used to generate nonce values for authenticating and encrypting messages.

-NID: A Network ID value used as an ID for identifying a network key.

SEQ: incremented each time a source device creates a new message, used to check for duplicate messages.

-SRC: A value representing the ID of the device that first generated the ID Mesh Packet of the 16-bit node.

-DST: ID (Node Address) of the device that the ID Mesh Packet of 16-bit Node should finally reach.

OP: An operation code (Opcode) indicating the operation to be performed by the device corresponding to the DST.

As another embodiment of the present invention, as described with reference to FIGS. 11 and 12, when the advertisement message is included with the network information and is transmitted, all the information cannot be included due to the limitation of the packet size. The rest of the network information that could not be transmitted through can be transmitted.

In this case, the advertisement message may include network information and the flag described above.

17 and 18, a mobile device requests network information related to a mesh network from a device forming a mesh network, forms a Bluetooth LE connection with the requested device, and receives the network information to receive the mesh network. It is possible to search the entire device constituting.

In detail, the first device 400 transmits a request message for requesting network information related to a mesh network to the second device 500 (S17010).

The request message may be transmitted to neighboring devices through broadcasting in the form of the above-mentioned Bluetooth advertisement message.

As shown in FIG. 18, the request message has a 2-byte header and payloads of various sizes.

The PDU type field included in the header may include an “ADV_MESH_IND” value indicating that the PDU type field is an advertisement message requesting the network information. If the PDU type field does not include the “ADV_MESH_IND” value, The AD Type may include a value indicating that the message is an advertisement message for requesting the network information.

Thereafter, the second device 500 may transmit an advertisement message including the network information to the first device 400 (S17020).

As described above with reference to FIGS. 11 and 12, the network information may include configuration information including information related to the configuration of the mesh network and device information related to each device forming the mesh network.

The step S17020 is an optional step and may not be performed in this embodiment.

If step S17020 is not performed or step S17020 is performed but all the network information has not been transmitted, the first device 400 as described above with reference to FIG. 6, the second device 500 In step S17030, a connection request message for establishing a Bluetooth LE connection may be received, and a Bluetooth LE connection may be formed through an authentication procedure and a security procedure (S17040).

The first device 400, which has established a Bluetooth LE connection with the second device 500, reads a read request message to request network information related to the mesh network stored in the GATT data base of the second device 500. Read Request message) is transmitted (17050).

Upon receiving the read request message, the second device 500 transmits a read response message including network information stored in a GATT data base to the first device 400 (S17060).

The network information stored in the GATT Data base of the second device 500 is the same as that of FIG. 14, and the format of the read response message is the same as that shown in FIG. 16.

As described above, the first device 400 that discovers all the devices constituting the mesh network through the read response message includes the devices constituting the mesh network using the packet formats shown in FIG. 12. It is possible to control the discovered device by sending and receiving a message and a control message or by transmitting a control message indicating a specific operation to a specific device.

The methods described with reference to FIGS. 11 to 18 may be performed individually, but may be mixed and used according to circumstances.

Referring to FIG. 19, when the devices constituting the mesh network are searched through the method described with reference to FIGS. 11 to 18, the devices may be output through the output unit of the mobile device.

Specifically, (a) the first device 400, which is a mobile device, may search for mesh network 1 and mesh network 2 through the method described with reference to FIGS. 11 to 18. .

(b) The first device 400 may output a search result through an output unit. For example, instead of individual devices constituting each mesh network, IDs of mesh networks such as G1 and G2, purposes of mesh networks such as light systems, and types of devices constituting the mesh network. And so on.

If the user selects a specific mesh network, (c) may output the devices constituting the specific mesh network. For example, an ID of the selected mesh network, a device type of the selected mesh network, and a device name of each device may be output.

In this case, the user may select individual devices configuring the mesh network through the rotary selection button.

Through the above method, the first device 400 may output the searched mesh network and the devices configuring the searched mesh network.

The present invention described above is capable of various substitutions, modifications, and changes without departing from the technical spirit of the present invention for those skilled in the art to which the present invention pertains. It is not limited by the drawings.

The present disclosure relates to the transmission and reception of Bluetooth data, and more particularly, to a method and apparatus for discovering a device in a mesh network using Bluetooth Low Energy (LE) technology.

Claims

In a mesh network of Bluetooth, a method of acquiring information of a device constituting a mesh network by a first device includes:

Receiving an advertisement message including at least one of configuration information or device information of the mesh network from a second device;

Transmitting a connection request message to the second device based on the advertisement message; And

Establishing a Bluetooth LE connection with the second device based on the connection request message.
The method of claim 1,

The configuration information includes at least one of ID information indicating the mesh network, type information of devices constituting the mesh network, configuration purpose information, name information of the mesh network, or information on the number of devices constituting the mesh network. How to.
The method of claim 1,

The device information includes at least one of name information, type information, or ID information of a specific device constituting the mesh network.
The method of claim 1,

Transmitting a scan request message requesting the configuration information or additional information related to device information to the second device; And

Receiving a response message including the additional information in response to the scan request message.
The method of claim 1,

The advertisement message further includes a flag indicating that the second device is a device obtaining configuration information or device information of the mesh network.
The method of claim 5, wherein

Sending a read request message requesting the configuration information or additional information related to device information to the second device; And

Receiving a read response message that includes the additional information in response to the read request message.
The method of claim 6,

The additional information may include ID information indicating the mesh network, type information of devices constituting the mesh network, configuration purpose information, name information of the mesh network, information on the number of devices constituting the mesh network, and the mesh network. And at least one of name information, type information, and ID information of a specific device.
In a mesh network of Bluetooth, a method of acquiring information of a device constituting a mesh network by a first device includes:

Transmitting a request message for requesting network information related to the mesh network to a second device;

Receiving a connection request message for establishing a Bluetooth LE connection to transmit the network information;

Establishing a Bluetooth LE connection with the second device based on the connection request message; And

Receiving a response message including the network information from the second device,

The network information includes at least one of configuration information or device information of the mesh network.
The method of claim 8,

The configuration information includes at least one of ID information indicating the mesh network, type information of devices constituting the mesh network, configuration purpose information, name information of the mesh network, or information on the number of devices constituting the mesh network. How to.
The method of claim 8,

The device information includes at least one of name information, type information, or ID information of a specific device constituting the mesh network.
The method of claim 8,

Receiving an advertising message comprising a portion of the network information.
In the first device for setting the role of the device in a mesh network of Bluetooth,

Communication unit for communicating with the outside by wireless or wired; And

Including a processor that is functionally connected with the communication unit, The processor,

Receiving an advertisement message including at least one of configuration information or device information of the mesh network from a second device;

Transmit a connection request message to the second device based on the advertisement message;

And control to form a Bluetooth LE connection with the second device based on the connection request message.