Access point and communication method

Abstract

An access point according to an embodiment of the present invention is used for multi-access point connection between a plurality of access points and a terminal, and includes an acquisition unit, a communication unit, and a control unit. The acquisition unit acquires, from each of the plurality of access points, role information indicating whether the access point is a first access point that communicates with the terminal, is a second access point that communicates with the first access point, or is capable of executing both functions of the first access point and the second access point. The communication unit is capable of supporting both the functions of the first access point and the second access point. The control unit controls the configuration of a role of an access point including the host in accordance with the role information and at least one of terminal information capable of identifying the distance between the host access point and the terminal, communication status information including the amount of data flow passing through the host access point, and path information of a network.

Description

Access points and communication methods

[0001] The embodiments relate to an access point and a communication method.

[0002] A wireless LAN (Local Area Network) is known as a communication system that wirelessly connects an access point and a wireless terminal device. By using the wireless LAN, the wireless terminal device can access a network via an AP (Access Point) within the communication area. IEEE 802.11bn assumes a multi-AP connection that includes multiple shared APs that communicate with the terminal and a sharing AP that aggregates and controls the multiple shared APs.

[0003] Arik Klein et al., “M-AP Coordinated Transmission framework”, IEEE802.11-23 / 1871, November 2023Jiayi Zhang et al., “Considerations on Multi-AP Operation”, IEEE802.11-23 / 1461r1, September 2023

[0004] In a multi-AP connection, multiple sharing APs are connected to one sharing AP, which may cause communication to be concentrated at the sharing AP, resulting in a bottleneck.

[0005] The present invention has been made in light of the above circumstances, and an object of the present invention is to provide an access point and a communication method that can realize faster and more efficient communication.

[0006] An access point according to an embodiment is an access point used for multi-access point connection between a plurality of access points and a terminal, and includes an acquisition unit, a communication unit, and a control unit. The acquisition unit acquires role information from the plurality of access points indicating whether the access point is a first access point that communicates with the terminal or a second access point that communicates with the first access point, and whether the access point is capable of performing the functions of both the first access point and the second access point. The communication unit is capable of supporting the functions of both the first access point and the second access point. The control unit controls the setting of the role of access points, including the access point itself, based on at least one of terminal information that can identify the distance between the access point itself and the terminal, communication status information that includes the amount of data flow passing through the access point, and network route information, as well as the role information.

[0007] According to the embodiment, it is possible to provide an access point and a communication method that can realize high-speed and efficient communication.

[0008] FIG. 1 is a block diagram showing an example of an access point and a terminal constituting a part of a communication system according to the present embodiment. FIG. 2 is a block diagram showing an example of the hardware configuration of an AP included in the communication system according to the present embodiment. FIG. 3 is a block diagram showing an example of the hardware configuration of a terminal device included in the communication system according to the present embodiment. FIG. 4 is a block diagram showing an example of the functional configuration of a sharing AP included in the communication system according to the present embodiment. FIG. 5 is a block diagram showing an example of the functional configuration of a shared AP included in the communication system according to the present embodiment. FIG. 6 is a block diagram showing an example of the functional configuration of a dual-mode AP included in the communication system according to the present embodiment. FIG. 7 is a block diagram showing an example of the functional configuration of a terminal device included in the communication system according to the present embodiment. FIG. 8 is a diagram showing an example of terminal information according to the present embodiment. FIG. 9 is a diagram showing an example of multi-AP management information and role information according to the present embodiment. FIG. 10 is a flowchart showing dynamic mode switching processing in the communication system according to the present embodiment. FIG. 11 is a flowchart showing a predetermined condition determination process and role control process for a dual-mode AP according to the present embodiment. FIG. 12 is a flowchart showing a predetermined condition determination process and role control process for a sharing AP according to the present embodiment. FIG. 13 is a flowchart showing a predetermined condition determination process and role control process for a shared AP according to the present embodiment. FIG. 14 is a diagram showing a first specific example of dynamic switching of network paths in the communication system according to the present embodiment. Fig. 15 is a diagram showing a second specific example of dynamic switching of network paths in the communication system according to the present embodiment. Fig. 16 is a diagram showing a third specific example of dynamic switching of network paths in the communication system according to the present embodiment. Fig. 17 is a diagram showing a fourth specific example of dynamic switching of network paths in the communication system according to the present embodiment.

[0009] Each embodiment will be described below with reference to the drawings. Each embodiment illustrates an apparatus or method for embodying the technical idea of ​​the invention. The drawings are schematic or conceptual. Hereinafter, the same reference numerals are used to designate components having substantially the same functions and configurations. The numbers following the letters that make up the reference numerals are used to distinguish between elements that are referred to by the reference numerals containing the same letters and have similar configurations. Similarly, each of the letters and "hyphen + number" following the numbers that make up the reference numerals is used to distinguish between elements that are referred to by the reference numerals containing the same numbers and have similar configurations. When it is not necessary to distinguish between elements indicated by reference numerals containing the same letters or numbers, these elements will be referred to by reference numerals containing only letters or numbers.

[0010] FIG. 1 is a block diagram illustrating an example of a minimum configuration of a multi-AP (access point) connection that constitutes part of a communication system according to an embodiment. As shown in FIG. 1, the communication system 1 includes a sharing AP 10, shared APs 20-1 and 20-2, and a terminal device 30. The sharing AP 10 is connected to a wide area network (WAN) 40. Each AP may also be referred to as a base station. In this specification, the shared APs 20-1 and 20-2 are also referred to as access points that "belong" to the sharing AP 10 in the multi-AP connection system. Conversely, when the shared APs 20-1 and 20-2 are viewed from the sharing AP 10, the shared APs 20-1 and 20-2 can also be considered "subordinate" access points of the sharing AP 10 in the multi-AP connection system.

[0011] The sharing AP 10 is, for example, an access point of a wireless LAN. The sharing AP 10 is configured to communicate wirelessly with a server (not shown) on the WAN 40. The sharing AP 10 is configured to communicate wirelessly with each of the shared AP 20-1 and the shared AP 20-2.

[0012] Each of the shared AP 20-1 and the shared AP 20-2 is, for example, a wireless LAN access point. Each of the shared AP 20-1 and the shared AP 20-2 is installed in a location physically separated from each other. The communication areas of the shared AP 20-1 and the shared AP 20-2 may overlap. Each of the shared AP 20-1 and the shared AP 20-2 is configured to wirelessly communicate with the terminal device 30. Communication between each of the shared AP 20-1 and the shared AP 20-2 and the terminal device 30 complies with, for example, the IEEE 802.11 standard.

[0013] The terminal device 30 is, for example, a wireless terminal such as a smartphone, a tablet terminal, or a PC (Personal Computer). In FIG. 1 , the terminal device 30 is located within the communication area of ​​the shared AP 20-1 and the shared AP 20-2. The terminal device 30 is configured to communicate with, for example, a server on the WAN 40 by communicating with the sharing AP 10 via at least one of the shared APs 20-1 and 20-2. In other words, it can be said that the terminal device 30 and the sharing AP 10 are wirelessly connected via at least one of the shared APs 20-1 and 20-2. Hereinafter, this type of wireless connection method between the terminal device 30 and the sharing AP 10 is referred to as a multi-AP connection method.

[0014] Furthermore, the terminal device 30 is a wireless terminal that supports multi-link communication, which performs communication using two or more channels. For example, the terminal device 30 includes a non-AP MLD, affiliated STA1, and affiliated STA2. The non-AP MLD is an MLD (multi-link device) on the terminal device 30 side that manages the link status of each of the affiliated STA1 and STA2 under its control. The non-AP MLD also performs processing to establish a wireless link with the sharing AP 10 in the multi-AP connection method.

[0015] In the multi-AP connection method, a wireless link is established between the AP MLD of the sharing AP 10 and the non-AP MLD of the terminal device 30 via the affiliated AP (not shown) of the shared AP 20-1 and a wireless link is established via the affiliated AP (not shown) of the shared AP 20-2. Then, each of the affiliated STA1 and affiliated STA2 of the terminal device 30 selects the established wireless link and performs data exchange. In this way, in the multi-AP connection method, the affiliated STA1 and affiliated STA2 of one terminal device 30 establish wireless links and communicate with the affiliated APs of multiple different shared APs 20. However, for simplicity of explanation, this will also be referred to as multiple APs and one terminal communicating via a multi-AP connection.

[0016] The example of the multi-AP connection method in Figure 1 shows a case where a sharing AP 10 and a terminal device 30 exchange data using a wireless link between an affiliated STA 1 and a shared AP 20-1, and a wireless link between an affiliated STA 2 and a shared AP 20-2.

[0017] The wireless communication used in the communication system 1 complies with, for example, the IEEE 802.11 standard. The IEEE 802.11 standard has wireless communication functions based on the OSI (Open Systems Interconnection) reference model. In the OSI reference model, wireless communication functions are divided into seven layers (Layer 1: Physical Layer, Layer 2: Data Link Layer, Layer 3: Network Layer, Layer 4: Transport Layer, Layer 5: Session Layer, Layer 6: Presentation Layer, and Layer 7: Application Layer). The data link layer includes a Logical Link Control (LLC) sublayer and a Media Access Control (MAC) sublayer. Frequency bands used in the wireless communication of the communication system 1 include, for example, the 2.4 GHz band, the 5 GHz band, the 6 GHz band, the 45 GHz band, and the 60 GHz band. Multiple channels are assigned to each frequency band.

[0018] Next, an example of the hardware configuration of the AP 50 included in the communication system 1 according to this embodiment will be described with reference to the block diagram shown in FIG.

[0019] In this embodiment, the AP 50 assumes a hardware configuration of a dual-mode AP 60 that can perform the roles of the sharing AP 10 and the shared AP 20 in both sharing mode and shared mode, in addition to the sharing AP 10 and shared AP 20 shown in Figure 1.

[0020] As shown in FIG. 2, the AP 50 includes, for example, a central processing unit (CPU) 11, a read only memory (ROM) 12, a random access memory (RAM) 13, a wireless communication module 14, and a wired communication module 15.

[0021] The CPU 11 is an integrated circuit capable of executing various programs and controls the overall operation of the AP 50. The ROM 12 is, for example, a non-volatile semiconductor memory that stores programs and control data for controlling the AP 50. The RAM 13 is, for example, a volatile semiconductor memory that serves as a work area for the CPU 11. The wireless communication module 14 is a circuit connected to an antenna and used to transmit and receive data via wireless signals, and is used when establishing a wireless connection between the terminal device 30 and the AP 50. The wired communication module 15 is a circuit used to transmit and receive data via wired signals, and is configured to be connectable to the WAN 40 when the sharing AP 10 or dual-mode AP 60 is in sharing mode, for example. The antenna may be built into the AP 50 or may be externally connected.

[0022] The AP 50 may have other hardware configurations. For example, the AP 50 may be wirelessly connected to the WAN 50. In this case, the AP 50 may not include the wired communication module 15, and a wireless communication module may be used instead of the wired communication module 15. The CPU 11 may also be called a "processor."

[0023] Next, an example of the hardware configuration of the terminal device 30 included in the communication system 1 according to this embodiment will be described with reference to the block diagram of Fig. 3. As shown in Fig. 3, the terminal device 30 includes, for example, a CPU 31, a ROM 32, a RAM 33, a wireless communication module 34, a display 35, and a storage 36.

[0024] The CPU 31 is a processing circuit that controls the overall operation of the terminal device 30. The ROM 32 is, for example, a non-volatile semiconductor memory. The ROM 32 stores programs and data for controlling the terminal device 30. The RAM 33 is, for example, a volatile semiconductor memory. The RAM 33 is used as a work area for the CPU 31. The wireless communication module 34 is a circuit connected to an antenna and used to send and receive data via wireless signals. The wireless communication module 34 is used when wirelessly connecting to the AP 50. The display 35 is, for example, an LCD (Liquid Crystal Display) or an EL (Electro-Luminescence) display. The display 35 displays a GUI (Graphical User Interface) corresponding to application software, etc. The storage 36 is a non-volatile storage device. The storage 36 stores system software, etc. for the terminal device 30. The CPU 31 may also be called a "processor."

[0025] Next, an example of the functional configuration of the sharing AP 10 included in the communication system 1 according to this embodiment will be described with reference to the block diagram of Fig. 4. The sharing AP 10 includes a management unit 110, an acquisition unit 120, a determination unit 130, a control unit 140, a wireless signal processing unit 150, and a wireless signal processing unit 160.

[0026] The management unit 110 manages terminal information and multi-AP management information. The terminal information is information that can identify the distance between the AP itself and the terminal device 30. The multi-AP management information is information about each AP related to the multi-AP connection, and in this embodiment, includes communication status information and network route information. The communication status information is information that includes the amount of data flow passing through the AP itself. The role information indicates whether the AP performs the role of a shared AP 20 (also referred to as a first access point) that communicates with the terminal device 30, the role of a sharing AP 10 (also referred to as a second access point) that communicates with the shared AP 20, or the role of both the shared AP 20 and the sharing AP 10. In other words, the role information indicates whether the AP is a sharing AP 10, a shared AP 20, or a dual-mode AP 60. Note that, if the AP is a dual-mode AP 60, the role information may also include information about its current role (sharing mode or shared mode).

[0027] The acquisition unit 120 acquires terminal information and role information shared by other APs. The acquisition unit 120 also acquires a request signal requesting a change of network path from the shared AP 20. The determination unit 130 determines whether the amount of data flow processed by itself is equal to or greater than a threshold.

[0028] When the data flow rate is equal to or greater than the threshold, the control unit 140 transmits a request signal to the dual-mode AP 60, requesting it to perform the role of the sharing AP 10, i.e., operate in sharing mode, based on communication status information including the data flow rate passing through the control unit 140. Furthermore, when the control unit 140 receives a request signal from the shared AP 20 requesting a change in the network path, the control unit 140 controls the network path to be changed by referring to the path information. For example, the control unit 140 controls the network path to reduce the data flow of the shared AP 20 that transmitted the request signal.

[0029] It is assumed that the wireless signal processing unit 150 and the wireless signal processing unit 160 each perform wireless communication using different frequency bands. The wireless signal processing unit 150 and the wireless signal processing unit 160 each transmit frames generated from an upper layer to the outside as wireless signals via an antenna. The wireless signal processing unit 150 and the wireless signal processing unit 160 also process wireless signals received by the antenna. When simultaneously notifying multiple shared APs 20, the wireless signal processing unit 150 and the wireless signal processing unit 160 may transmit beacon signals or the like by multicast or broadcast.

[0030] Next, an example of the functional configuration of the shared AP 20 included in the communication system 1 according to this embodiment will be described with reference to the block diagram of Fig. 5. The shared AP 20 includes a management unit 210, an acquisition unit 220, a determination unit 230, a control unit 240, a wireless signal processing unit 250, and a wireless signal processing unit 260. Compared to the sharing AP 10, the shared AP 20 is similar to the sharing AP 10 except for the information stored in the management unit 210 and the operation of the control unit 240.

[0031] The management unit 210 manages terminal information and multi-AP management information. Role information may also be managed. When the amount of data flow processed by the control unit 240 is equal to or greater than a threshold, the control unit 240 controls the sharing AP 10 to transmit communication status information including the amount of data flow passing through the control unit 240 and a request signal requesting a change of the network path.

[0032] Next, an example of the functional configuration of the dual-mode AP 60 included in the communication system 1 according to this embodiment will be described with reference to the block diagram of Fig. 6. The dual-mode AP 60 includes a management unit 610, an acquisition unit 620, a determination unit 630, a control unit 640, a mode setting unit 670, a wireless signal processing unit 650, and a wireless signal processing unit 660.

[0033] The management unit 610 manages terminal information and role information. The acquisition unit 620 acquires the terminal information and role information. The determination unit 630 determines whether the distance between the terminal device 30 and itself is within a threshold based on the terminal information. The determination unit 630 also determines whether the amount of data flow processed by itself is equal to or greater than a threshold.

[0034] The control unit 640 controls the setting of the role of the AP, including itself, and the network route, based on at least one of the terminal information and the communication status information, and the role information. Specifically, when the distance is within a threshold, the control unit 640 controls the mode setting unit 670 so that the AP itself executes the shared mode. Based on the communication status information including the amount of data flow passing through the control unit 640, the control unit 640 transmits a request signal to the dual-mode AP requesting that it operate in the sharing mode. Furthermore, when the control unit 640 receives a request signal from another AP requesting that it operate in the sharing mode, the control unit 640 controls the dual-mode AP to operate in the sharing mode via the mode setting unit 670.

[0035] The mode setting unit 670 sets its own role to sharing mode, shared mode, or dual mode.

[0036] Radio signal processing units 650 and 660 perform the same processing as radio signal processing units 150 and 160, respectively, and therefore detailed description thereof will be omitted.

[0037] Next, an example of the functional configuration of the terminal device 30 included in the communication system 1 according to this embodiment will be described with reference to the block diagram of FIG.

[0038] The terminal device 30 includes a management unit 310 , a data processing unit 320 , a control unit 330 , a quality measurement unit 340 , a radio signal processing unit 350 and a radio signal processing unit 360 .

[0039] The management unit 310 manages link management information, which includes information indicating the status of wireless links with each AP used in the multi-AP connection.

[0040] Data processing unit 320 extracts data from the radio signal received by at least one of radio signal processing unit 350 and radio signal processing unit 360, and processes the data so that it can be used by a higher-level application.

[0041] The control unit 330 controls the logical wireless connection between the sharing AP 10 in the multi-AP connection and the non-AP MLD of the terminal device 30. For example, the control unit 330 controls the wireless link based on multi-AP management information included in a beacon frame from the shared AP 20.

[0042] The quality measurement unit 340 measures the quality of each wireless link connected to the wireless signal processing units 350 and 360. The quality of the wireless link is evaluated by measuring, for example, the received power, the amount of delay, jitter, etc.

[0043] The wireless signal processing unit 350 and the wireless signal processing unit 360 receive wireless signals transmitted from the shared AP 20, convert them into wireless frames, and send the wireless frames to downstream processing units such as the data processing unit. The wireless signal processing unit 350 and the wireless signal processing unit 360 convert the data input from the data processing unit 320 into wireless signals and transmit them to the outside.

[0044] Next, an example of terminal information according to this embodiment is shown in FIG. 8 . As shown in FIG. 8 , the terminal information includes information indicating the status and location of the wireless link between the shared AP 20 used in the multi-AP connection and the affiliated STA of the terminal device 30. In the example of FIG. 8 , the information includes information indicating the status of the wireless link between the shared AP 20-1 and the shared AP 20-2 and the affiliated STA #1 and the affiliated STA #2 of the terminal device 30, as well as the status of the wireless link between the shared AP 20-1 and the shared AP 20-2 and the affiliated STA #1 and the affiliated STA #2 of the terminal device 30. "Enable" indicates a state in which data exchange using the wireless link between the shared AP of the corresponding identifier and the affiliated STA is enabled. "Disable" indicates a state in which data exchange using the wireless link between the shared AP of the corresponding identifier and the affiliated STA is disabled. The location is information about at least one of the absolute location of the terminal device 30, the relative location of the terminal device 30 and the AP itself, and the received signal strength indicator (RSSI) of the signal from the terminal device 30.

[0045] Next, an example of multi-AP management information and role information according to this embodiment is shown in Fig. 9. As shown in Fig. 9, the multi-AP management information is a table showing the correspondence between AP identifiers, capabilities, destinations, communication status, and route information for the sharing AP 10, the shared AP 20, and the dual-mode AP 60. Information showing the correspondence between AP identifiers and capabilities corresponds to role information.

[0046] The AP identifier is an identifier that uniquely identifies an access point. The capability is information about the role (mode) that the access point can support, and is either "sharing" only, "shared" only, or "sharing / shared," i.e., both sharing mode and shared mode. The destination is the AP identifier of the sharing AP 10 to which the shared AP 20 belongs. The communication status is the data rate of data passing through the information corresponding to the communication status itself, or a data rate estimate equivalent to the data rate, or an estimated airtime occupancy rate, and may be ranked (A, B, C, etc.) according to, for example, communication quality. The route information is, for example, the source address and destination address of the data flow, or information equivalent to the addresses.

[0047] For example, a terminal with an AP identifier of “AP#2” among the shared APs has the capability “sharing / shared”, and therefore it is known to be a dual-mode AP 60 .

[0048] Next, the dynamic mode switching process in the communication system according to this embodiment will be described with reference to the flowchart in Fig. 10. Here, it is assumed that the dual-mode AP 60, the sharing AP 10, and the shared AP 20 that make up the network each perform the process at predetermined intervals, but this is not limiting and the process may also be performed when a new AP or terminal device 30 joins the communication system.

[0049] In step SA1, the wireless transceiver of each AP transmits and receives terminal information, multi-AP management information, and role information between adjacent APs or between the APs to which the AP belongs or subordinate APs. In other words, the terminal information, multi-AP management information, and role information are shared between APs that make up the network of the communication system.

[0050] The terminal information to be shared may include at least one of the absolute position of the terminal device 30, the relative position of the terminal device 30 and the AP itself, and the received signal strength indicator (RSSI) of the signal from the terminal device 30. When an AP transmits and receives terminal information, multi-AP management information, and role information to and from adjacent APs, the AP may, for example, broadcast its own role information and the terminal information and multi-AP management information it holds, while receiving information broadcast from the adjacent AP. Note that the timing of transmitting and receiving the terminal information, multi-AP management information, and role information, i.e., the timing at which the terminal information, multi-AP management information, and role information are shared, may be when a new AP joins the network, when a certain period of time has elapsed, when the network topology has changed, or the like.

[0051] In step SA2, the determination unit of each AP determines whether at least one of the location and communication conditions based on the terminal information satisfies a predetermined condition. The predetermined condition indicates, for example, a condition that results in inefficient communication due to the distance from the terminal, or a condition that results in a bottleneck in communication, such as a large number of connected terminals, a large amount of data related to the data flow, or poor communication conditions. If the predetermined condition is satisfied, the process proceeds to step SA3. If the predetermined condition is not satisfied, the process returns to step SA2 and repeats the same process.

[0052] In step SA3, the control unit of each AP controls the setting of the role of APs, including itself, and the network route, based on at least one of the terminal information, communication status, and route information, and the role information. For example, when changing the role of an AP, if the dual-mode AP is operating as a sharing AP, it is set to operate as a shared AP, and if the dual-mode AP is operating as a shared AP, it is set to operate as a sharing AP. Alternatively, the dual-mode AP may be set to perform the functions of both a shared AP and a sharing AP. When requesting a role change, a request signal is sent to a neighboring AP or another AP with which it belongs, requesting that the role of the other AP be changed.

[0053] Next, the process of determining whether a predetermined condition is met and the process of controlling the role of the dual-mode AP 60, which correspond to steps SA3 and SA4, will be described with reference to the flowchart of Fig. 11. Note that the processes of steps SB1, SB5, and SB9 are executed in parallel.

[0054] In step SB1, the determination unit 630 of the dual-mode AP 60 determines whether the distance between itself and the terminal position of the terminal device 30 is equal to or less than a threshold value. If the distance between itself and the terminal position is equal to or less than the threshold value, the process proceeds to step SB2, and if the distance between itself and the terminal position is greater than the threshold value, the process proceeds to step SB3.

[0055] In step SB2, the wireless signal processors 650 and 660 of the dual mode AP 60 notify the other APs that they will set themselves to the shared mode.

[0056] In step SB3, the control unit 640 of the dual-mode AP 60 sets itself to the shared mode via the mode setting unit 670, and communicates with the terminal device 30 that is located at a distance equal to or less than the threshold. In step SB4, since the distance between itself and the terminal device 30 is large, the role is not changed.

[0057] In step SB5, the determination unit 630 of the dual-mode AP 60 determines whether the amount of data flow passing through the dual-mode AP 60 is equal to or greater than a threshold. If the amount of data flow is equal to or greater than the threshold, the process proceeds to step SB6. If the amount of data flow is less than the threshold, the process proceeds to step SB4, and the role is not changed.

[0058] In step SB6, the determination unit 630 of the dual-mode AP 60 determines whether its role is a sharing AP. If its role is a sharing AP, the process proceeds to step SB7. If its role is a shared AP rather than a sharing AP, the process proceeds to step SB8.

[0059] In step SB7, the control unit 640 and the wireless signal processing units 650 and 660 of the dual-mode AP 60 transmit a request signal to operate in the sharing mode to the dual-mode AP 60 that belongs to the same set of shared APs or that has the largest number of the same terminals among the set of shared APs, among the subordinate dual-mode APs 60 that are operating in the shared mode. This allows the dual-mode AP 60 to share the role of the sharing AP 10, thereby reducing the possibility that the dual-mode AP 60 itself will become a bottleneck in the data flow in the network.

[0060] In step SB8, the control unit 640 and the radio signal processing units 650 and 660 of the dual-mode AP 60 transmit a request signal to the sharing AP to which the dual-mode AP belongs, requesting that the sharing AP review the data flow allocation with other shared APs.

[0061] In step SB9, the determination unit 630 of the dual-mode AP 60 determines whether or not a request signal has been received from another AP. If a request signal has been received from another AP, the process proceeds to step SB10. If a request signal has not been received from another AP, the process proceeds to step SB4, and the role is not changed.

[0062] In step SB10, when the control unit 640 of the dual-mode AP 60 receives a request signal from another AP via the mode setting unit 670, the control unit 640 controls the role and data flow according to the request signal. For example, when the dual-mode AP 60's role is a shared AP, if the control unit 640 receives a request signal to change its role to a sharing AP shown in step SB7, the dual-mode AP 60 changes its mode from shared to sharing. Alternatively, when the dual-mode AP 60 is in sharing mode, if the dual-mode AP 60 receives a request signal to review the data flow allocation with other shared APs, the dual-mode AP 60 reorganizes the data flow paths for the multiple shared APs under its control.

[0063] Next, the process of determining whether a predetermined condition is met and the process of controlling a role of the sharing AP 10, which correspond to steps SA3 and SA4, will be described with reference to the flowchart of FIG.

[0064] In step SC1, the determination unit 130 of the sharing AP 10 determines whether the amount of data flowing through the sharing AP 10 is equal to or greater than a threshold. If the amount of data flow is equal to or greater than the threshold, the process proceeds to step SC2. If the amount of data flow is less than the threshold, the process continues to step SC1, and the amount of data flowing through the sharing AP 10 is monitored.

[0065] In step SC2, the control unit 140 and the wireless signal processing units 150 and 160 of the sharing AP 10 transmit a request signal to change the role of the sharing AP to the dual-mode AP that belongs to the same set of shared APs or that has the largest number of the same terminals among the set of shared APs, among the subordinate dual-mode APs operating in the shared mode. This allows the dual-mode AP to share the role of the sharing AP, thereby reducing the possibility that the dual-mode AP itself will become a bottleneck in the data flow in the network.

[0066] Next, the process of determining whether a predetermined condition is met and the process of controlling the role of the shared AP 20, which correspond to steps SA3 and SA4, will be described with reference to the flowchart of FIG.

[0067] In step SD1, the determination unit 230 of the shared AP 20 determines whether the amount of data flowing through itself is equal to or greater than a threshold. If the amount of data flow is equal to or greater than the threshold, the process proceeds to step SD2. If the amount of data flow is less than the threshold, the process continues to step SD1, and the amount of data flowing through itself is monitored.

[0068] In step SD2, the control unit 240 and wireless signal processing units 250, 260 of the single shared AP send a request signal to the sharing AP 10 to which it belongs (or the dual-mode AP 60 in sharing mode) to review the data flow allocation with other shared APs 20.

[0069] Although the dynamic mode switching processes shown in Figures 11 to 13 have been described as processes autonomously executed by each AP, the entire network may be managed by a controller (not shown), a specific sharing AP 10, or a dual-mode AP 60. For example, the controller, the specific sharing AP 10, or the dual-mode AP 60 collects and centrally manages role information, terminal connection status, and communication status from each AP. The controller, the specific sharing AP 10, or the dual-mode AP 60 may change the affiliation of the sharing AP and the shared AP and switch the connection based on various centrally managed information and predetermined conditions, or may instruct the dual-mode AP whether to operate as a sharing AP or a shared AP. This allows the communication status of the network to be grasped and determined based on various centrally managed conditions, and the operating instructions to each AP to be dynamically switched.

[0070] Next, a first specific example of dynamic switching of network paths in the communication system 1 according to this embodiment will be described with reference to Fig. 14. In the network shown in Fig. 14(a), four shared APs (AP #2 to AP #5) belong to one sharing AP (AP #1), and the sharing AP 10 and three terminal devices 30 (STA #1 to STA #3 in the figure) communicate via a multi-AP connection. It is assumed that AP #1 is the sharing AP 10 that operates only in sharing mode, AP #2 is a dual-mode AP 60, and AP #3 to AP #5 are shared APs 20 that operate only in shared mode.

[0071] STA#1 communicates with AP#2 and AP#3 via a multi-AP connection. STA#2 communicates with AP#2 and AP#4 via a multi-AP connection. STA#3 communicates with AP#4 and AP#5 via a multi-AP connection.

[0072] Here, as shown in FIG. 14(a), it is assumed that the data flow volume of AP #1, which is a sharing AP 10, is equal to or greater than a threshold. In this case, as shown in FIG. 14(b), AP #1 transmits a request signal to AP #2, which is a subordinate dual-mode AP, to change to sharing mode. The request signal specifies AP #3 and AP #4 as the shared APs 20 to be subordinate, and specifies the targets for multi-AP connection with STA #1. Upon receiving the request signal, AP #2, which is a dual-mode AP, sets its own mode to change from shared mode to sharing mode. In addition, in accordance with the request signal, AP #2 uses AP #3 and AP #4 as shared APs 20 and communicates with STA #1 via multi-AP connection.

[0073] As a result, the data flow to the WAN, which was previously entirely borne by AP#1, can now be shared between AP#1 and AP#2, thereby preventing a decrease in communication speed.

[0074] Next, a second specific example of dynamic switching of network paths in the communication system according to this embodiment will be described with reference to Fig. 15. The network shown in Fig. 15(a) is the same as that shown in Fig. 14(a). In Fig. 15(a), it is assumed that the data flow volume of AP #4, which is a shared AP 20, is equal to or greater than a threshold.

[0075] In Figure 15(b), the network path is reconstructed by referencing the path information. That is, AP #4 transmits a request signal to AP #1, the sharing AP 10 to which it belongs, to review the allocation of data flow with other shared APs (AP #2, AP #3, AP #5). When AP #1 receives this request signal, it sets the data flow path so that AP #3 also communicates with STA #1 and STA #2, in order to prevent data flow concentration on AP #4. This reduces the concentration of data flow on AP #4.

[0076] Next, a third specific example of dynamic switching of network paths in the communication system according to this embodiment will be described with reference to Fig. 16. The network path shown in Fig. 16(a) is in the same state as that shown in Fig. 15(b). Fig. 16 assumes that STA #4 has newly joined the network.

[0077] 16(b) assumes that AP #2 determines, based on terminal location information, that the distance between AP #2 and STA #4 is equal to or less than a threshold. AP #2 sets STA #4 to operate in shared mode and notifies another sharing AP, AP #1, that AP #2 will operate in shared mode with STA #4. Upon receiving this notification, AP #1 determines AP #2 and AP #3, which are close to STA #4, as shared APs 20 and establishes a multi-AP connection with STA #4. In other words, AP #2 can act as a sharing AP for STA #1 and STA #2, while also acting as a shared AP for STA #4. In other words, AP #2 can operate in a dual mode, which allows both sharing mode and shared mode to be performed in parallel.

[0078] As a result, when a new terminal device 30 joins, the AP closest to the newly joined terminal device 30 is selected as the shared AP, thereby improving the communication efficiency of the multi-AP connection.

[0079] Next, a fourth specific example of dynamic switching of network paths in the communication system according to this embodiment will be described with reference to Fig. 17 . As shown in Fig. 17 , all APs may be configured as dual-mode APs 60. In Fig. 17 , AP #2 operates in sharing mode, AP #1 and AP #3 operate in shared mode and communicate with STA #1, and AP #3 and AP #4 operate in shared mode and communicate with STA #2. If all APs are configured as dual-mode APs 60, network paths can be switched more dynamically.

[0080] According to the present embodiment described above, role information indicating whether the device will operate in a shared AP only mode, a sharing AP only mode, or a mode switchable between a shared AP and a sharing AP mode is acquired, and the settings of the roles of access points including the device itself and the network routes are controlled according to the role information and at least one of the terminal information and the communication status information. As a result, for an AP that is overloaded with communications due to an excessive data flow or the like, the network route can be reconstructed to reduce the load, thereby achieving faster communications, lower power consumption, and improved efficiency.

[0081] In the above-described embodiments, the CPUs installed in the sharing AP 10, the shared AP 20, the dual-mode AP 60, and the terminal device 30 may be other circuits (or processors). For example, an MPU (micro processing unit) or the like may be provided instead of a CPU. Each of the processes described in each embodiment may be realized by dedicated hardware. The processes of the sharing AP 10, the shared AP 20, the dual-mode AP 60, and the terminal device 30 may be a mixture of processes executed by software and processes executed by hardware, or may be only one of them.

[0082] In the above embodiment, the flowcharts used to explain the operations are merely examples. The order of the operations described in the embodiment may be changed to the extent possible, or other processes may be added. A wireless communication standard other than the IEEE 802.11 standard may be used as the wireless communication standard.

[0083] The present invention is not limited to the above-described embodiments, and various modifications can be made in the implementation stage without departing from the spirit of the invention. Furthermore, the embodiments may be implemented in appropriate combinations, in which case the combined effects can be obtained. Furthermore, the above-described embodiments include various inventions, and various inventions can be extracted by combining selected elements from the disclosed elements. For example, if the problem can be solved and the desired effect can be obtained even if some elements are deleted from all elements shown in the embodiments, the configuration from which these elements are deleted can be extracted as an invention.

[0084] 1...Communication system 3...Terminal device 14...Wireless communication module 15...Wired communication module 20, 20-1, 20-2...Shared AP 30...Terminal device 34...Wireless communication module 35...Display 36...Storage 110, 210, 310, 610...Management unit 120, 220, 620...Acquisition unit 130, 230, 630...Determination unit 140, 240, 330, 640...Control unit 150, 160, 250, 260, 350, 360, 650, 660...Wireless signal processing unit 320...Data processing unit 340...Quality measurement unit 670...Mode setting unit

Claims

1. An access point used for multi-access point connection between a plurality of access points and a terminal, comprising: an acquisition unit that acquires from the plurality of access points role information indicating whether the access point is a first access point that communicates with the terminal, or a second access point that communicates with the first access point, and whether it is capable of performing the functions of both the first access point and the second access point; a communication unit that is compatible with the functions of both the first access point and the second access point; and a control unit that controls the setting of the role of access points including itself, in accordance with at least one of terminal information that can identify the distance between itself and the terminal, communication status information including the amount of data flow passing through itself, and network route information, and the role information.

2. The access point according to claim 1, wherein the terminal information includes at least one of the absolute position of the terminal, the relative position of the terminal and the access point itself, and a received signal strength value related to the terminal; and the access point further comprises a determination unit that determines whether the distance between the terminal and the access point itself is within a threshold based on the terminal information; and the control unit controls the access point to perform the role of the first access point if the distance is within the threshold.

3. The access point of claim 1, further comprising a determination unit that determines whether the amount of data flow it processes is equal to or greater than a threshold, and when the amount of data flow is equal to or greater than the threshold, the control unit transmits a request signal to another access point based on the communication status information and the route information, requesting that the other access point perform the role of the second access point.

4. The access point described in claim 3, wherein when the access point itself performs the role of the second access point, the control unit transmits the request signal to the access point that has the largest number of common attributes with the plurality of first access points that belong to the access point itself when the access point itself performs the role of the second access point, and the role information indicates that the access point performs the roles of both the first access point and the second access point.

5. The access point described in claim 1, wherein the acquisition unit acquires a request signal from another access point requesting that the access point perform the role of the second access point, and the control unit controls the access point to perform the role of the second access point in accordance with the request signal, the communication status information, and the route information.

6. A communication method used for multi-access point connection between a plurality of access points and a terminal, wherein an acquisition means acquires role information from the plurality of access points indicating whether the access point is a first access point communicating with the terminal or a second access point communicating with the first access point, and whether it is capable of performing the functions of both the first access point and the second access point; a communication means supports the functions of both the first access point and the second access point; and a control means controls the setting of the role of the access points, including itself, according to at least one of terminal information capable of identifying the distance between itself and the terminal, communication status information including the amount of data flow passing through itself, and network route information, and the role information.

Images