Information processing device and information processing method

Abstract

This information processing device provides the ability to automatically and quickly construct a wireless network suitable for the communication environment when handing over from a mesh network to a wireless LAN. [Solution] The information processing device includes an acquisition means for acquiring information indicating the communication status between each of a plurality of nodes that communicate with each other using a first communication method, and adjacent nodes that can communicate directly with the node; and a determination means for determining at least one of the plurality of nodes as the upper node based on the information indicating the communication status when the first communication method is switched to a second communication method in which a plurality of lower nodes communicate with each other via an upper node.

Description

Technical Field

[0001] The present invention relates to an information processing apparatus and an information processing method for constructing a wireless network.

Background Art

[0002] There is a technology for handing over a communication method between wireless communication devices capable of communicating with a plurality of wireless communication standards to a low-speed and low-power consumption communication standard or a high-speed and high-power consumption communication standard according to the communication function used. Patent Document 1 discloses a technology for shortening the time required for handover from Bluetooth (Registered Trademark) Low Energy (hereinafter BLE) to a wireless LAN in wireless communication between a digital camera and a mobile phone. In BLE communication, communication is performed between a central (digital camera) of a higher node having a role of controlling communication and a peripheral (mobile phone) of a lower node connected to the higher node, so the communicable area is configured centering around the central.

[0003] Bluetooth (Registered Trademark) Mesh, which is an extended function of BLE, is a technology for using BLE as a mesh network. In Bluetooth (Registered Trademark) Mesh, since there is no upper and lower relationship between devices (nodes) such as a central and a peripheral in BLE communication, the communicable area can be expanded by adjacent nodes relaying and transmitting data in a bucket relay manner. In the wireless communication between the digital camera and the mobile phone of Patent Document 1, by replacing BLE with Bluetooth (Registered Trademark) Mesh, each node can perform wireless communication with more devices existing in a wider range.

[0004] In the IEEE 802.11 wireless LAN standard, clients (hereinafter also referred to as CLs) are connected in infrastructure mode, communicating with each other via access points (hereinafter also referred to as APs). When handing over from BLE to wireless LAN, the central becomes the AP, which is the upper-level node of the wireless LAN network. Therefore, peripherals that were connected to the central can communicate with the AP as lower-level nodes (CLs) after the handover to wireless LAN. In other words, it was not anticipated that each CL would be outside the communication area of ​​the AP.

[0005] On the other hand, in the case of Bluetooth® Mesh, there is no hierarchical relationship between nodes, such as upper and lower nodes, so the node (device) that becomes the AP after handover to the wireless LAN is determined. Furthermore, because adjacent devices expand their communication area, some devices may fall outside the AP's communication range after handover to the wireless LAN.

[0006] Patent Document 2 discloses a method for comparing the functional information of each wireless communication device to determine which wireless communication device will operate as an AP. However, if the AP is determined based on functional information without considering the communication environment, it is not guaranteed that all wireless communication devices in the network will be within communication range. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2017-103650 [Patent Document 2] Japanese Patent Publication No. 2010-245847 [Overview of the project] [Problems that the invention aims to solve]

[0008] During a handover from a mesh network to a wireless LAN, if there are devices that go outside the communication range after the handover, it may be difficult to automatically establish a wireless LAN connection configuration in a short amount of time.

[0009] Therefore, the present invention aims to provide an information processing device that can automatically and quickly construct a wireless network suitable for the communication environment when handing over from a mesh network to a wireless LAN. [Means for solving the problem]

[0010] The information processing device according to the present invention is characterized by having an acquisition means for acquiring information indicating the communication status between each of a plurality of nodes that communicate with each other using a first communication method, and adjacent nodes that can communicate directly with the node, and a determination means for determining at least one of the plurality of nodes as the upper node based on the information indicating the communication status when the first communication method is switched to a second communication method in which a plurality of lower nodes communicate with each other via an upper node. [Effects of the Invention]

[0011] According to the present invention, when handing over from a mesh network to a wireless LAN, it becomes possible to automatically and quickly construct a wireless network suitable for the communication environment. [Brief explanation of the drawing]

[0012] [Figure 1] This is a diagram illustrating the configuration of a digital camera. [Figure 2] This is a diagram illustrating the configuration of a mobile phone. [Figure 3] This figure shows examples of wireless network connections using various communication methods. [Figure 4] This is a flowchart illustrating the handover process. [Figure 5] This is a sequence diagram illustrating the collection of communication status and functional information. [Figure 6]A table exemplifying information indicating the communication status of a digital camera. [Figure 7] A table exemplifying the communication status and function information of each node. [Figure 8] A flowchart exemplifying the determination process of an access point. [Figure 9] A sequence diagram explaining a wireless LAN connection.

Embodiments for Carrying Out the Invention

[0013] <Embodiment> Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the embodiments described below are examples of means for realizing the present invention, and may be appropriately modified or changed according to the configuration of the device to which the present invention is applied and various conditions. Also, it is possible to appropriately combine the respective embodiments.

[0014] <Configuration of Digital Camera> FIG. 1 is a diagram exemplifying the configuration of a digital camera 100. The digital camera 100 is an example of a communication device capable of communicating by a plurality of communication methods. The communication device is not limited to the digital camera 100, and may be an electronic device such as a portable media player, a tablet device, or a personal computer. A communication device forming a wireless network is also referred to as a node. The digital camera 100 includes a control unit 101, an imaging unit 102, an operation unit 103, a display unit 104, a wireless communication unit 105, and a short-range wireless communication unit 106.

[0015] The control unit 101 controls the entire digital camera 100 according to the input signal and a program for realizing the functions of each part of the digital camera 100. Instead of controlling the entire digital camera 100 by a program, the control unit 101 may control the entire digital camera 100 by causing a plurality of hardware to execute the processing of each part.

[0016] The imaging unit 102 includes, for example, an optical lens unit, an optical system that controls the aperture, zoom, focus, etc., and an imaging device for converting the light (video) introduced through the optical lens unit into an electrical video signal. The imaging unit 102 converts the subject light imaged by the lens included in the imaging unit 102 into an electrical signal by the imaging device under the control of the control unit 101. The imaging unit 102 outputs the digital data obtained by performing noise reduction processing, etc. on the converted electrical signal as image data.

[0017] The operation unit 103 is an operation member used to receive instructions from the user for the digital camera 100. The operation unit 103 includes, for example, a power button for the user to instruct the on / off of the power of the digital camera 100, a release switch for instructing shooting, and a playback button for instructing the playback of image data. The operation unit 103 also includes a touch panel formed on the display unit 104.

[0018] The display unit 104 displays the viewfinder image during shooting, the captured image data, and character information for interactive operations, etc. Note that the display unit 104 may not be provided in the digital camera 100. The digital camera 100 only needs to have a display control function for connecting to an externally arranged display unit 104 and controlling the display of the connected display unit 104.

[0019] The wireless communication unit 105 is a communication interface for connecting to an external device. The digital camera 100 can transmit and receive data to and from an external device such as a mobile phone 200 via the wireless communication unit 105. For example, the wireless communication unit 105 transmits the image data generated by the imaging unit 102 to an external device. The wireless communication unit 105 includes an interface for communicating with an external device via a wireless LAN compliant with the IEEE802.11 standard. The control unit 101 realizes wireless communication with an external device by controlling the wireless communication unit 105. Note that the communication method of the wireless communication unit 105 is not limited to wireless LAN and includes, for example, an infrared communication method.

[0020] The short-range wireless communication unit 106 includes, for example, an antenna for wireless communication, a modulation / demodulation circuit for processing wireless signals, and a communication controller. The short-range wireless communication unit 106 outputs a modulated wireless signal from the antenna. By demodulating the wireless signal received by the antenna, the short-range wireless communication unit 106 realizes short-range wireless communication compliant with the IEEE 802.15 standard (so-called Bluetooth®). The short-range wireless communication unit 106 is also compatible with Bluetooth® Mesh.

[0021] Bluetooth® communication has a narrower communication range and shorter communication distance compared to Wi-Fi communication. Furthermore, Bluetooth® communication is slower than Wi-Fi communication. On the other hand, Bluetooth® communication consumes less power than Wi-Fi communication. Also, the communication speed achieved by the wireless communication unit 105 is faster than the communication speed achieved by the short-range wireless communication unit 106.

[0022] The wireless communication unit 105 can switch between AP mode, which operates the digital camera 100 as an access point (AP) in infrastructure mode, and CL mode, which operates it as a client (CL) in infrastructure mode.

[0023] In CL mode, the digital camera 100 can operate as a CL device in infrastructure mode. When operating as a CL device, the digital camera 100 can connect to surrounding AP devices and participate in the network formed by AP devices.

[0024] Furthermore, the digital camera 100, in AP mode, uses a simplified AP (hereinafter referred to as simplified AP). It can operate as a simple AP. A simple AP is a type of AP, but with more limited functionality. When the digital camera 100 operates as a simple AP, the digital camera 100 forms its own network. Peripheral devices of the digital camera 100 recognize the digital camera 100 as an AP device and can join the network formed by the digital camera 100.

[0025] <Mobile phone configuration> Figure 2 illustrates the configuration of a mobile phone 200. The mobile phone 200 is an example of an information processing device according to the present invention. The information processing device is not limited to the mobile phone 200, but may be an electronic device such as a digital camera with wireless functionality, a tablet device, or a personal computer. The mobile phone 200 has a control unit 201, an operation unit 202, a display unit 203, a communication unit 204, and a short-range wireless communication unit 205.

[0026] The control unit 201 controls the entire mobile phone 200 according to the input signals and a program that implements the functions of each part of the mobile phone 200. Instead of controlling the entire mobile phone 200 by program, the control unit 201 may control the entire mobile phone 200 by having multiple hardware components perform the processing of each part.

[0027] The operation unit 202 is an operating component used to receive instructions from the user to the mobile phone 200. The operation unit 202 includes, for example, a power button for the user to instruct the mobile phone 200 to turn on / off, and a touch panel formed on the display unit 203.

[0028] The display unit 203 displays image data and text information for interactive operation. The display unit 203 does not necessarily have to be present in the mobile phone 200. The mobile phone 200 only needs to have a display control function that connects to an externally located display unit 203 and controls the display of the connected display unit 203.

[0029] The communication unit 204 is a communication interface for connecting to an external device. The mobile phone 200 can send and receive data with an external device such as a digital camera 100 via the communication unit 204. The communication unit 204 includes an antenna. The control unit 201 can connect to the digital camera 100 wirelessly via the antenna of the communication unit 204. The communication unit 204 may be connected directly to the digital camera 100, or it may be connected to the digital camera 100 via an access point in infrastructure mode.

[0030] The communication unit 204 can use, for example, PTP / IP (Picture Transfer Protocol over Internet Protocol) via a wireless LAN as a protocol for communicating data. However, communication with the digital camera 100 is not limited to PTP / IP. For example, the communication unit 204 may be an infrared communication module, a Bluetooth® communication module, or a wireless communication module such as WirelessUSB. Furthermore, the communication unit 204 may employ wired connections such as USB, HDMI®, and IEEE1394.

[0031] The short-range wireless communication unit 205 includes, for example, an antenna for wireless communication, a modulation / demodulation circuit for processing the wireless signal, and a communication controller. The short-range wireless communication unit 205 outputs a modulated wireless signal from the antenna. The short-range wireless communication unit 106 realizes short-range wireless communication compliant with the IEEE 802.15 standard (so-called Bluetooth®) by demodulating the wireless signal received by the antenna. The short-range wireless communication unit 106 is also compatible with Bluetooth® Mesh.

[0032] Bluetooth® communication has a narrower communication range and shorter communication distance compared to Wi-Fi communication. Also, Bluetooth® communication is slower than Wi-Fi communication. On the other hand, Bluetooth® communication consumes less power than Wi-Fi communication.

[0033] <Network System Configuration> Figure 3 shows examples of wireless network connections for each communication method. The network system shown in Figure 3 includes digital cameras 301-304 having a configuration similar to digital camera 100, and a mobile phone 300 having a configuration similar to mobile phone 200. The mobile phones 300 and digital cameras 301-304 that form the wireless network are also referred to as nodes, terminals, or devices. The mobile phones 300 and digital cameras 301-304 are capable of communication over a mesh network using Bluetooth® Mesh. Communication over a mesh network such as Bluetooth® Mesh is an example of the first communication method. In the first communication method, multiple nodes (digital cameras 301-304) that form a mesh network can communicate with each other, and each of the multiple nodes does not have a relationship with a higher-level node or lower-level node. The dotted lines connecting the devices in Figure 3 show an example of connection when devices that are adjacent nodes communicate with each other using a mesh network.

[0034] Furthermore, the mobile phone 300 and digital cameras 301-304 can also communicate using a wireless LAN communication method compliant with the IEEE 802.11 standard. The wireless LAN communication method compliant with the IEEE 802.11 standard is an example of a second communication method in which multiple lower nodes communicate with each other via a higher node. The higher node functions as an access point (AP), and the lower nodes function as clients (CL). In Figure 3, the solid lines connecting the devices show an example of connection when digital camera 303, operating in AP mode, communicates with digital cameras 301, 302, 304 and mobile phone 300, which are operating in CL mode, using wireless LAN.

[0035] <Overview of Handover Process> Referring to Figure 4, the flow of the handover process will be explained. In this embodiment, the handover is a vertical handover, which switches the currently used communication method or communication interface to another communication method or other communication interface to continue communication.

[0036] The handover process shown in Figure 4 is initiated when, for example, a connection has been established between each node of the digital cameras 301-304 and the mobile phone 300 using a Bluetooth® Mesh network, as illustrated by the dotted lines in Figure 3. The handover process is performed when the mesh network (first communication method) is switched to wireless LAN (second communication method). The handover process is initiated when the control unit 201 of the mobile phone 300 detects a specific signal or operation to initiate the handover.

[0037] In the following description, the handover process shown in Figure 4 is performed by the mobile phone 300, which is an information processing device according to the present invention. The information processing device may be any of the devices forming the mesh network, and the handover process may be performed by any of the digital cameras 301 to 304, which are also information processing devices. In the following description, the devices on the mesh network (mobile phone 300 and digital cameras 301 to 304) are also referred to as nodes.

[0038] In step S401, the control unit 201 of the mobile phone 300 broadcasts a handover request to other devices on the mesh network. In step S402, the control units 201 communicate with each other using Bluetooth® Mesh. Communication status and functional information are acquired from each of the multiple nodes on the mesh network. Specifically, the control unit 201 acquires information indicating the communication status between a node and neighboring nodes that can communicate directly with that node.

[0039] In step S403, the control unit 201 determines which node will operate as an access point (AP), which is the higher-level node in the wireless LAN after the handover, based on the information obtained from each node in step S402. Based on the information indicating the communication status obtained from each node in step S402, the control unit 201 determines at least one of the nodes to be the AP. The AP may be one node or multiple nodes. In addition to the information indicating the communication status, the control unit 201 may also determine the AP based on the functional information of each node.

[0040] In step S404, the control unit 201 sends an AP request to the node determined in step S403, requesting it to operate as an AP. In step S405, the node that received the AP request in step S404 (the node determined to be an AP) sends wireless LAN authentication information to each node on the mesh network to be used for wireless LAN connection. In step S406, the node determined to be an AP activates the wireless LAN AP function and establishes wireless LAN connections with each node on the mesh network.

[0041] <Sending handover requests, obtaining communication status and function information> The handover process shown in Figure 4 will be explained in detail, specifically the handover request transmission process in step S401 and the acquisition of signal status and function information in step S402. The handover process is executed when a specific signal or operation indicating a handover is detected. The specific operation is, for example, pressing a predetermined button included in the operation unit 103 of the digital camera 100, or pressing a predetermined button included in the operation unit 202 of the mobile phone 300. The specific signal is, for example, a signal received from a node (digital camera 100) connected to the communication unit 204 of the mobile phone 300.

[0042] Referring to Figure 5, the communication flow between each node during the handover request transmission process and the communication status / function information acquisition process will be explained. The control unit 201 of the mobile phone 300 detects a predetermined operation to instruct a handover via the operation unit 202, or detects a predetermined signal to instruct a handover via the communication unit 204.

[0043] Upon instruction from the control unit 201, the short-range wireless communication unit 205 broadcasts a handover request to each node on the mesh network. The short-range wireless communication unit 205 first communicates directly with the adjacent nodes, digital cameras 301, 303, and 304, and sends them the handover request.

[0044] In step S501, the short-range wireless communication unit 205 sends a handover request to the digital camera 304. When the short-range wireless communication unit 106 of the digital camera 304 receives the handover request, it returns a response to the mobile phone 300 indicating that it was successfully received. In step S502, the short-range wireless communication unit 205 sends a handover request to the digital camera 303. When the short-range wireless communication unit 106 of the digital camera 303 receives the handover request, it returns a response to the mobile phone 300 indicating that it was successfully received. In step S503, the short-range wireless communication unit 205 sends a handover request to the digital camera 301. When the short-range wireless communication unit 106 of the digital camera 301 receives the handover request, it returns a response to the mobile phone 300 indicating that it was successfully received.

[0045] In step S504, the short-range wireless communication unit 106 of the digital camera 304 is connected to the handheld device. The handover request is sent (forwarded) to the neighboring node, with information indicating that the sender of the handover request is the mobile phone 300 added. When the short-range wireless communication unit 106 of the digital camera 304 receives a handover request from the mobile phone 300, it responds to the mobile phone 300 and forwards the handover request to the neighboring node, the digital camera 303.

[0046] Similar to step S504, in step S505, the digital cameras 301, 302, and 303 add information indicating that the source of the handover request is the mobile phone 300 and send (transfer) the handover request to the neighboring node. In Figure 5, the details of the processing in step S505 are omitted.

[0047] Although the mobile phone 300 is among the neighboring nodes of the digital camera 304, the digital camera 304 does not forward the handover request to the mobile phone 300, which is the source node, in order to avoid the handover request being sent repeatedly indefinitely. For similar reasons, a node that has received a handover request and forwarded it to a neighboring node will not resend the handover request to the neighboring node that has already sent it, even if it receives another handover request from another node.

[0048] Each node, including the mobile phone 300, acquires the number of neighboring nodes, the neighboring nodes with which it communicated, and the strength of the radio waves received during communication with those neighboring nodes (hereinafter referred to as "received strength") when exchanging handover requests and responses to handover requests. Each node records the acquired number of neighboring nodes and received strength in a storage unit as information indicating the communication status. The received strength can be acquired by the short-range radio communication unit 106 or the short-range radio communication unit 205.

[0049] Figure 6 is a table illustrating information showing the communication status of digital camera 304. Digital camera 304 has 2 neighboring nodes. Digital camera 304 is adjacent to mobile phone 300 and digital camera 303, and the received signal strengths from each neighboring node are -65.0 dB and -60.0 dB.

[0050] Since the received signal strength is a value obtained from communication during the period of handover requests and responses to handover requests, it may temporarily decrease due to obstacles during communication. To avoid such sudden events, each node may set a period for measuring the received signal strength before and after sending and receiving handover requests or responses. Each node can record the received signal strength obtained during the measurement period as information indicating the communication status. However, for nodes of mobile devices used by users while on the move, such as smartphones and tablet devices, the measurement period should preferably be relatively short, as the received signal strength may change in real time. Also, the period for measuring the communication status may be set to the most recent period.

[0051] Each node in the mesh network, after a predetermined time has elapsed since the last handover request it receives, transmits information indicating the communication status and functional information to the mobile phone 300 that sent the handover request. The information indicating the communication status includes the number of neighboring nodes, information on neighboring nodes with which it communicated, and the signal strength received from those neighboring nodes. The functional information includes information indicating whether its own node can operate as an AP in wireless LAN communication.

[0052] In step S510, the short-range wireless communication unit 106 of the digital camera 304 transmits information indicating the communication status of the digital camera 304 and functional information to the mobile phone 300. When the short-range wireless communication unit 205 of the mobile phone 300 receives the information from the digital camera 304, it returns a response to the digital camera 304 indicating that it has been successfully received. In step S511, the digital camera 303, similar to step S510, transmits information to the mobile phone 300. In step S512, the digital camera 301 transmits information indicating the communication status and function information of the digital camera 301 to the mobile phone 300, similar to step S510, and receives a response from the mobile phone 300.

[0053] The digital camera 302 which is not an adjacent node of the mobile phone 300 can communicate with the mobile phone 300 via the digital camera 303 or the digital camera 301 which are adjacent nodes. In step S513, the short-range wireless communication unit 106 of the digital camera 302 transmits information indicating the communication status of the digital camera 302 and function information to the digital camera 303. When the short-range wireless communication unit 106 of the digital camera 303 receives the information from the digital camera 302, it returns a response indicating that the reception was normal to the digital camera 302. In step S514, the short-range wireless communication unit 106 of the digital camera 303 transfers information indicating the communication status of the digital camera 302 and function information to the mobile phone 300. When the short-range wireless communication unit 205 of the mobile phone 300 receives the information from the digital camera 302, it returns a response indicating that the reception was normal to the digital camera 303.

[0054] FIG. 7 is a table illustrating the communication status and function information of each node. As shown in FIG. 7, the control unit 201 of the mobile phone 300 stores information indicating the communication status of each node received by the short-range wireless communication unit 205 and function information, and information indicating its own communication status and function information.

[0055] The table shown in FIG. 7 includes items of device, AP function, adjacent node, number of adjacent nodes, reception intensity, and average reception intensity. The device is an item indicating a node forming a mesh network. The AP function is an item indicating whether each device has a function to operate as an access point. The adjacent node is an item indicating an adjacent node connected to each device. The number of adjacent nodes is an item indicating the number of adjacent nodes connected to each device. The reception intensity is an item indicating the reception intensity of radio waves from the corresponding adjacent node. The average reception intensity is an item indicating the average value of the reception intensities of the adjacent nodes connected to each device.

[0056] <Selection of AP> Referring to Figure 8, the AP determination in step S403 of Figure 4 will be explained. Figure 8 is a flowchart illustrating the access point determination process. The access point determination process is performed by the mobile phone 300, which is the source of the handover request.

[0057] A mesh network is a communication method that does not have the concept of upper and lower nodes, and communicates with adjacent nodes. Wireless LAN is a communication method in which lower nodes (CLs) are connected to upper nodes (APs), and CLs communicate with each other via APs. In a handover from a mesh network to a wireless LAN, the selection of APs is important in order to ensure that each node is within the communication range of the AP after the handover. In order for each node to be within the communication range of the AP even in the wireless LAN after the handover, the mobile phone 300 selects an AP that can connect to more nodes in the mesh network and with better communication conditions.

[0058] In step S801, the control unit 201 of the mobile phone 300 obtains the number of devices to perform a handover. The control unit 201 can obtain the number of devices to be handed over from, for example, the communication status information and functional information of each device as described in Figure 7.

[0059] The control unit 201 may also obtain the number of devices connected on the mesh network using a known method such as PING. If the devices to be handed over from the wireless LAN are pre-configured, the number of devices configured to be handed over may be obtained.

[0060] In step S802, the control unit 201 determines whether the number of devices n (n>1) subject to handover is greater than 2. If the number of devices n=2, the process proceeds to step S803. If the number of devices n>2, the process proceeds to step S804.

[0061] In step S803, the control unit 201 refers to the functional information of each device and determines that the device with AP functionality will be the AP for wireless LAN communication. By designating the device that sent the handover request as the AP, the control unit 201 can omit sending the AP request in step S404 of Figure 4. By omitting the AP request sending process, the control unit 201 can reduce the time required for the handover process.

[0062] In step S804, the control unit 201 refers to the functional information of each device, extracts devices that have AP functionality, and compares the number of adjacent nodes of the extracted devices. In step S805, the control unit 201 extracts the device with the largest number of adjacent nodes. The control unit 201 determines whether the number of devices m with the largest number of adjacent nodes is greater than 1. If the number of devices m = 1, the process proceeds to step S806. If the number of devices m > 1, the process proceeds to step S807.

[0063] In step S806, the control unit 201 determines the device with the most neighboring nodes to be the AP. In step S807, the control unit 201 determines the device with the highest average received signal strength (the average of the received signal strengths of the neighboring nodes of each device) to be the AP.

[0064] In the example shown in Figure 7, among the digital cameras 301, 302, 303, and 304, which have AP functionality, digital cameras 301 and 303 have the most neighboring nodes. The control unit 201 determines that digital camera 303, which has the highest average received signal strength obtained by averaging the received signal strength with each neighboring node, is the AP.

[0065] In the example shown in Figure 8, the control unit 201 determines the AP by comparing the number of neighboring nodes in step S804 and the average received signal strength of neighboring nodes in step S807. However, the AP may also be determined based on either the number of neighboring nodes or the average received signal strength.

[0066] In step S808, the control unit 201 determines whether or not to issue a warning to the operator (user) of each device. The control unit 201 determines to issue a warning to the user if, for example, there is a device that may be outside the AP's communication range after the handover. The control unit 201 of the mobile phone 300 that sent the handover request checks whether the device to be handed over is an adjacent node of the device determined to be the AP. If there is a device (node) that is not an adjacent node of the device determined to be the AP, the control unit 201 estimates that there is a device that may be outside the AP's communication range after the handover and determines to issue a warning.

[0067] In the example in Figure 7, if digital camera 303 is determined to be the AP, it is presumed that digital camera 302 will be outside the communication range of digital camera 303 because it is not an adjacent node to digital camera 303. In this way, if there is a device that is not an adjacent node to the device determined to be the AP, the control unit 201 determines that there is a device that may be outside the communication range of the AP after handover to the wireless LAN, and therefore issues a warning.

[0068] Furthermore, if the network is constructed with devices such that the communication range of each device via wireless LAN is significantly greater than the communication range of each device via Bluetooth® Mesh, the conditions for issuing a warning may be relaxed. For example, the control unit 201, In a mesh network, the decision to issue a warning may be based on the number of hops, which is the number of communications involved in sending data from a source node through relay nodes to a destination node. Specifically, the control unit 201 may decide to issue a warning if there are devices that are 3 or more hops away from the device determined to be the AP.

[0069] If it is determined in step S808 that a warning should be issued, the process proceeds to step S809. If it is determined that no warning should be issued, the process shown in Figure 8 terminates.

[0070] In step S809, the control unit 201 presents a warning to the user. The control unit 201 may display the warning on the display unit 203 of the mobile phone 300 that sent the handover request. When there are operators operating the digital cameras 301 to 304, the control unit 201 may transmit the warning information to the digital cameras 301 to 304 via the short-range wireless communication unit 205 and instruct the display of the warning. The digital cameras 301 to 304 display the received warning information on the display unit 104 in response to the instruction for warning display.

[0071] <Transmission of AP request, transmission of wireless LAN authentication information, wireless LAN connection> Among the handover processes shown in FIG. 4, the transmission process of the AP request in step S404, the transmission process of the wireless LAN authentication information in step S405, and the wireless LAN connection process in step S406 will be described. Referring to FIG. 9, the communication flow between each node in the transmission process of the AP request, the transmission process of the wireless LAN authentication information, and the wireless LAN connection process will be described.

[0072] In step S901, the short-range wireless communication unit 205 of the mobile phone 300 that sent the handover request transmits an AP request to the digital camera 303 determined as the AP in the wireless LAN after handover. The short-range wireless communication unit 205 can transmit the AP request to the digital camera 303 via the mesh network. When the short-range wireless communication unit 106 of the digital camera 303 receives the AP request, it returns a response indicating that the AP request has been received to the mobile phone 300.

[0073] The control unit 101 of the digital camera 303 sets wireless LAN authentication information for network connection in the wireless LAN. The wireless LAN authentication information includes SSID, encryption key, authentication method, and channel information. The wireless LAN authentication information may be stored in advance in the storage unit of each device, or may be generated by the control unit 101 or the control unit 201 when each device is determined as the AP.

[0074] In step S902, the near-field radio communication unit 106 of the digital camera 303, which has received an AP request, transmits wireless LAN authentication information to the mobile phone 300 performing the handover via the mesh network. The near-field radio communication unit 205 of the mobile phone 300 returns a response to the digital camera 303 indicating that it has received the wireless LAN authentication information. Similarly, in steps S903 and S904, the near-field radio communication unit 106 of the digital camera 303 also transmits wireless LAN authentication information to the digital cameras 301 and 304 performing the handover via the mesh network. The digital cameras 301 and 304 return a response to the digital camera 303 indicating that it has received the wireless LAN authentication information.

[0075] The mobile phone 300 and digital cameras 301 and 304, having received the wireless LAN authentication information, transmit the wireless LAN authentication information to neighboring nodes. The mobile phone 300 and digital cameras 301 and 304 do not need to transmit the wireless LAN authentication information to neighboring nodes to which they have already transmitted it. In step S905, the short-range wireless communication unit 106 of the digital camera 301 transmits the wireless LAN authentication information to the digital camera 302, which is performing the handover, via the mesh network. The communication unit 106 returns a response to the digital camera 301 indicating that it has received wireless LAN authentication information.

[0076] In step S906, the control unit 101 of the digital camera 303 activates the wireless communication unit 105 and starts AP mode, which operates as an AP based on wireless LAN authentication information. In step S907, the control unit 201 of the mobile phone 300 activates the wireless LAN function of the communication unit 204 and prepares to connect to the AP as a CL in infrastructure mode. In steps S908 to S910, the control unit 101 of the digital cameras 301, 302, and 304 activates the wireless LAN function of the wireless communication unit 105 and starts CL mode for operation as a CL.

[0077] When the digital camera 303 starts operating as an AP, the wireless communication unit 105 of the digital camera 303 starts transmitting a beacon to notify the surroundings of the presence of the AP. The mobile phone 300 and the digital cameras 301, 302, and 304 operate as CLs. The communication unit 204 of the mobile phone 300 and the wireless communication unit 105 of the digital cameras 301, 302, and 304 can detect APs operating with the SSID of the wireless LAN authentication information.

[0078] In step S911, the communication unit 204 of the mobile phone 300 establishes a wireless LAN connection with the detected AP, the digital camera 303. The wireless communication unit 105 of the digital camera 303 returns a response to the mobile phone 300 indicating that it has authenticated the wireless LAN connection. Similarly, in steps S912 to S914, the wireless communication units 105 of the digital cameras 301, 302, and 304 establish a wireless LAN connection with the detected AP, the digital camera 303. The wireless communication unit 105 of the digital camera 303 returns a response to the digital cameras 301, 302, and 304 indicating that it has authenticated the wireless LAN connection.

[0079] In the above embodiment, the mobile phone 300, which is an information processing device according to the present invention, determines the AP after the handover based on information indicating the communication status in the mesh network during a handover from the mesh network to the wireless LAN. As a result, the mobile phone 300 can automatically and quickly construct the wireless LAN network so that more devices (nodes) are within the communication range of the AP after the handover.

[0080] The present invention also includes cases in which a software program that realizes the functions of the above-described embodiments is supplied directly from a recording medium or via wired / wireless communication to a system or device having a computer capable of executing the program and executed. The program code itself supplied to and installed on the computer in order to realize the functions and processes of the above-described embodiments can realize the present invention. In other words, the present invention also includes the computer program itself for realizing the functions and processes of the above-described embodiments. The computer program may be object code, a program executed by an interpreter, script data supplied to an OS, etc., as long as it has the functions of a program, and is not limited to the form of a program.

[0081] The recording medium for supplying the program may be, for example, a hard disk, a magnetic recording medium such as magnetic tape, an optical / magneto-optical storage medium, or a non-volatile semiconductor memory. Furthermore, the computer program that implements the functions and processing of the embodiment may be stored on a server on a computer network and supplied to the client computer by the client computer connecting to the server and downloading it.

[0082] The various controls described above may or may not be performed by a single piece of hardware (e.g., a processor or circuit). Multiple pieces of hardware (e.g., multiple processors, multiple circuits, or a combination of one or more processors and one or more circuits) may share the processing. This allows for control of the entire device.

[0083] Furthermore, the above-mentioned processors are processors in a broad sense, including general-purpose processors and specialized processors. General-purpose processors include, for example, CPUs (Central Processing Units), MPUs (Micro Processing Units), and DSPs (Digital Signal Processors). Specialized processors include, for example, GPUs (Graphics Processing Units), ASICs (Application Specific Integrated Circuits), and PLDs (Programmable Logic Devices). Programmable logic devices include, for example, FPGAs (Field Programmable Gate Arrays) and CPLDs (Complex Programmable Logic Devices).

[0084] Furthermore, the embodiments described above (including modified examples) are merely examples, and configurations obtained by appropriately modifying or changing the above-described configurations within the scope of the gist of the present invention are also included in the present invention. Configurations obtained by appropriately combining the above-described configurations are also included in the present invention.

[0085] <Other Embodiments> The present invention can also be realized by supplying a program that implements one or more of the functions of the above-described embodiments to a system or device via a network or storage medium, and by having one or more processors in the computer of that system or device read and execute the program. It can also be realized by a circuit that implements one or more functions.

[0086] This embodiment includes the following configurations, methods, and programs. (Composition 1) For each of a plurality of nodes communicating with each other using a first communication method, an acquisition means is provided to acquire information indicating the communication status between the node and adjacent nodes that can communicate directly with the node. When the first communication method is switched to a second communication method in which multiple lower nodes communicate with each other via a higher node, a determination means determines that at least one of the multiple nodes will be the higher node based on information indicating the communication status. An information processing device characterized by having the following features. (Configuration 2) In the first communication method described above, the plurality of nodes can communicate with each other, and each of the plurality of nodes does not have a relationship with the other as an upper-level node or lower-level node. The information processing device according to configuration 1, characterized by the above. (Composition 3) The information indicating the communication status includes at least one of the following: the number of neighboring nodes of the node, and the intensity of radio waves that the node receives from the neighboring nodes. An information processing device according to configuration 1 or 2, characterized by the above. (Composition 4) The determination means determines that the node with the largest number of neighboring nodes among the plurality of nodes will be the upper-level node in the second communication method. An information processing device according to any one of configurations 1 to 3, characterized by the above. (Composition 5) The determination means determines, among the plurality of nodes, the node with the highest average value of the radio wave intensity received from the adjacent nodes as the upper node in the second communication method. An information processing device according to any one of configurations 1 to 4, characterized by the above. (Composition 6) The determination means determines that, among the plurality of nodes, the node having the function of the higher-level node is the higher-level node in the second communication method. An information processing device according to any one of configurations 1 to 5, characterized by the above. (Composition 7) The information processing device according to any one of configurations 1 to 6, characterized in that the second communication method is a communication method based on the IEEE 802.11 standard, the upper node functions as an access point, and the lower node functions as a client. (Composition 8) The system further includes a means for displaying a warning to the user if, after the first communication method has been switched to the second communication method, there are nodes that may be outside the communication range of the higher-level node. An information processing device according to any one of configurations 1 to 7, characterized by the above. (Composition 9) The notification means displays the warning if there is a node among the plurality of nodes that is not an adjacent node of the higher-level node. The information processing apparatus according to configuration 8, characterized by the above. (method) For each of a plurality of nodes communicating with each other using a first communication method, the step of obtaining information indicating the communication status between the node and adjacent nodes that can communicate directly with the node; When the first communication method is switched to a second communication method in which multiple lower nodes communicate with each other via a higher node, the steps include determining at least one of the multiple nodes to be the higher node based on information indicating the communication status. An information processing method characterized by having the following features. (program) A program for causing a computer to function as one of the means of the information processing device described in any of configurations 1 to 9. [Explanation of symbols]

[0087] 200, 300: Mobile phone (information processing device), 201: Control unit, 205: Short-range wireless communication unit

Claims

1. For each of a plurality of nodes communicating with each other using a first communication method, an acquisition means is provided to acquire information indicating the communication status between the node and adjacent nodes that can communicate directly with the node. When the first communication method is switched to a second communication method in which multiple lower nodes communicate with each other via a higher node, a determination means determines that at least one of the multiple nodes will be the higher node based on information indicating the communication status. An information processing device characterized by having the following features.

2. In the first communication method described above, the plurality of nodes can communicate with each other, and each of the plurality of nodes does not have a relationship with the other as an upper-level node or lower-level node. The information processing apparatus according to feature 1.

3. The information indicating the communication status includes at least one of the following: the number of neighboring nodes of the node, and the intensity of radio waves that the node receives from the neighboring nodes. The information processing apparatus according to feature 1.

4. The determination means determines that the node with the largest number of neighboring nodes among the plurality of nodes will be the upper-level node in the second communication method. The information processing apparatus according to feature 1.

5. The determination means determines, among the plurality of nodes, the node with the highest average value of the radio wave intensity received from the adjacent nodes as the higher-level node in the second communication method. The information processing apparatus according to feature 1.

6. The determination means determines, among the plurality of nodes, the node that has the function of the higher-level node, to be the higher-level node in the second communication method. The information processing apparatus according to feature 1.

7. The information processing device according to claim 1, characterized in that the second communication method is a communication method based on the IEEE 802.11 standard, the upper node functions as an access point, and the lower node functions as a client.

8. The system further includes a means for displaying a warning to the user if, after the first communication method has been switched to the second communication method, there are nodes that may be outside the communication range of the higher-level node. The information processing apparatus according to feature 1.

9. The notification means displays the warning if there is a node among the plurality of nodes that is not an adjacent node of the higher-level node. The information processing apparatus according to feature 8.

10. For each of a plurality of nodes communicating with each other using a first communication method, the step is to acquire information indicating the communication status between the node and adjacent nodes that can communicate directly with the node. When the first communication method is switched to a second communication method in which multiple lower nodes communicate with each other via a higher node, the steps include determining at least one of the multiple nodes to be the higher node based on information indicating the communication status. An information processing method characterized by having the following features.

11. The computer is used as one of the means in the information processing apparatus described in any one of claims 1 to 9. A program to enable this function.

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