JP4894772B2 - Wireless communication apparatus, communication system, program, and route determination method - Google Patents

Description

  The present invention relates to a wireless communication device, a communication system, a program, and a route determination method.

  In recent years, a wireless multi-hop network in which a plurality of wireless communication apparatuses operate autonomously and distributed and can easily expand a communication area has attracted attention. In such a wireless multi-hop network, a communication path between a transmission source apparatus and a reception destination apparatus is determined by a routing protocol, and data is transmitted from the transmission source apparatus along the determined communication path.

  A configuration in which a wireless multi-hop network is connected to a different wired network via a gateway device is also assumed. Here, even when data can be transmitted from the transmission source device to the reception destination device using only the wireless multi-hop network, it is better to use the wired network in consideration of the wireless band in the wireless multi-hop network. is there.

  For example, there is a difference between the number of hops from a transmission source device to a reception destination device on a communication path using only a wireless multi-hop network and the number of hops from a transmission source device to a reception destination device on a communication path using a wired network. If there are few, a method of using a wired network can be considered. For example, Patent Document 1 discloses a method for searching for a communication path using only a wireless multi-hop network and a communication path using a wired network. According to such a search method, the transmission source device transmits a route search message, the gateway device that has received the route search message transfers the route search message, and the other gateway device receives the transferred route search message. The gateway device searches for the communication route to the destination device, the other gateway device transmits the communication route searched via the transfer source gateway device to the source device, and the source device transmits to the destination device. Get the communication path when using a wired network.

Japanese Patent Laid-Open No. 2002-64546

  However, in the conventional search method, after the transmission source device transmits a route search message and the above-described series of processing is performed, the transmission source device acquires a communication path when using a wired network to the reception destination device. To do. For this reason, there has been a problem that it takes an appropriate time to obtain a communication path when the transmission source device uses a wired network to the reception destination device.

  Therefore, the present invention has been made in view of the above problems, and the object of the present invention is to obtain a communication path via a gateway device to another wireless communication device more quickly. It is an object to provide a new and improved wireless communication apparatus, communication system, program, and route determination method.

  In order to solve the above-described problem, according to an aspect of the present invention, a first route through a plurality of gateway devices that connect an arbitrary network and one or more wireless communication devices and the arbitrary network, or There is provided a wireless communication device that communicates with another wireless communication device using a second route through a surrounding wireless communication device without going through the arbitrary network.

  Each of the plurality of gateway devices has route information to the one or more wireless communication devices to be connected to the arbitrary network, and further connects the wireless communication device to the arbitrary network. The target gateway device acquires the route information included in the other gateway device whose connection target is the other wireless communication device with the arbitrary network via the arbitrary network.

  In addition, the wireless communication device uses the first route based on route information acquired from the other gateway device by a gateway device to which the wireless communication device is to be connected to the arbitrary network. A first hop number acquisition unit that acquires the number of hops to the other wireless communication device, and a second hop number that acquires the hop number to the other wireless communication device when the second route is used According to the acquisition unit, the number of hops of the first route acquired by the first hop number acquisition unit, and the number of hops of the second route acquired by the second hop number acquisition unit, A determination unit that determines which of the first route and the second route is used to communicate with the other wireless communication device.

  In such a configuration, the number of hops to another wireless communication device when the first route is used, the route information acquired from the other gateway device by the gateway device whose own device is a connection target with an arbitrary network Get based on. Accordingly, the wireless communication device does not need to actually search for a route to any other wireless communication device via an arbitrary network. Therefore, when the first route is used, the number of hops to the other wireless communication device is further increased. Can be acquired early. As a result, the determination unit can efficiently determine the communication route based on the number of hops of the first route and the number of hops of the second route.

  When the difference between the number of hops of the first route and the number of hops of the second route is equal to or greater than a predetermined value, the determination unit uses the route with the smaller number of hops to use the other wireless communication. It may be determined that communication is performed with the apparatus. In such a configuration, the wireless communication device uses the route with the smaller number of hops when the difference in the number of hops is equal to or greater than a predetermined value regardless of the characteristics of the first route and the second route. Then, it communicates with other wireless communication devices. Therefore, the possibility that the data transmitted from the wireless communication device reaches another wireless communication device or the time required for the data transmitted from the wireless communication device to reach another wireless communication device is further advantageous. Can be.

  Each of the communication devices constituting the arbitrary network is connected by wire, and the determination unit is configured such that a difference between the number of hops of the first route and the number of hops of the second route is a predetermined value or less, and When the bandwidth of the transmission data to the other wireless communication device is equal to or less than a reference value, it may be determined that communication with the other wireless communication device is performed using the first route. In such a configuration, when the difference in the number of hops is equal to or smaller than a predetermined value and the bandwidth of the transmission data is equal to or smaller than the reference value, the wireless communication device uses the first route through any network to transmit another wireless Communicate with the communication device. Here, the arbitrary network is a wired network. Therefore, the wireless communication device can communicate with other wireless communication devices by avoiding contention in the wireless band by using an arbitrary network even if the number of hops is slightly disadvantageous as described above. Can do. Further, when the bandwidth of the transmission data is equal to or greater than the reference value, the wireless communication device uses the second route to transmit data to the gateway device that is the connection target of the wireless communication device with an arbitrary network. The case where traffic is concentrated can be suppressed.

  The determination unit is configured such that a difference between the number of hops of the first route and the number of hops of the second route is equal to or less than a predetermined value, and a bandwidth of transmission data to the other wireless communication device is equal to or greater than a reference value In this case, it may be determined which of the first route and the second route is used to communicate with the other wireless communication device according to the data type of the transmission data. Here, the first route is a route through an arbitrary network which is a wired network, and the reliability of communication is high. Therefore, the wireless communication device can communicate with other wireless communication devices using a more appropriate communication path according to the data type of the transmission data as described above.

  The wireless communication device may further include a receiving unit that receives path information acquired by the gateway device from a gateway device that connects the wireless communication device and the arbitrary network.

  The first hop number acquisition unit determines the number of hops from the other gateway device to the other wireless communication device included in the route information received by the reception unit, and the wireless communication device and the arbitrary network. The number of hops to the other wireless communication device in the case where the first route is used by adding the number of hops to the gateway device that connects the devices may be acquired.

  The first hop number acquisition unit requests the gateway device that connects the wireless communication device and the arbitrary network to acquire the hop number to the other wireless communication device, and the gateway device acquires the other hop number. The number of hops to the other wireless communication device obtained in the gateway device based on the route information obtained from the gateway device may be obtained from the gateway device.

  In order to solve the above-described problem, according to another aspect of the present invention, a plurality of gateway devices connecting an arbitrary network and one or more wireless communication devices, the plurality of gateway devices, and the arbitrary A communication system including a first communication path through a network or a wireless communication apparatus that communicates with another wireless communication apparatus using a second path through a surrounding wireless communication apparatus without going through the arbitrary network. Provided. Each of the plurality of gateway devices has route information to the one or more wireless communication devices to be connected to the arbitrary network, and further connects the wireless communication device to the arbitrary network. The target gateway device acquires the route information included in the other gateway device whose connection target is the other wireless communication device with the arbitrary network via the arbitrary network. In addition, the wireless communication device uses the first route based on route information acquired from the other gateway device by a gateway device to which the wireless communication device is to be connected to the arbitrary network. A first hop number acquisition unit that acquires the number of hops to the other wireless communication device, and a second hop number that acquires the hop number to the other wireless communication device when the second route is used According to the acquisition unit, the number of hops of the first route acquired by the first hop number acquisition unit, and the number of hops of the second route acquired by the second hop number acquisition unit, A determination unit that determines which of the first route and the second route is used to communicate with the other wireless communication device.

  In order to solve the above problems, according to another aspect of the present invention, an arbitrary network and one or more wireless communication devices are connected, and route information to the one or more wireless communication devices is obtained. And the first route through the gateway device that acquires the route information possessed by another gateway device via the arbitrary network and the arbitrary network, or the surrounding radio without passing through the arbitrary network A computer provided in a wireless communication device that communicates with another wireless communication device using a second path via the communication device is connected to the other wireless communication device by a gateway device that connects the wireless communication device and the arbitrary network. Based on the route information acquired from another gateway device connecting the communication device and the arbitrary network, the first process is performed. A first hop number acquisition unit that acquires the number of hops to the other wireless communication device when using the second and a hop number to the other wireless communication device when the second route is used The second hop number acquisition unit, the hop number of the first route acquired by the first hop number acquisition unit, and the hop of the second route acquired by the second hop number acquisition unit According to the number, a program is provided for functioning as a determination unit that determines which of the first route and the second route is used to communicate with the other wireless communication device. .

  Such a program can cause the hardware resources of a computer including, for example, a CPU, a ROM, or a RAM to execute the functions of the first hop number acquisition unit, the second hop number acquisition unit, and the determination unit as described above. . That is, it is possible to cause a computer that uses the program to function as the above-described first hop number acquisition unit, second hop number acquisition unit, and determination unit.

  In order to solve the above-described problem, according to another aspect of the present invention, a plurality of gateway devices connecting an arbitrary network and one or more wireless communication devices, the plurality of gateway devices, and the arbitrary A path executed in a first communication path with a network or a wireless communication apparatus that communicates with another wireless communication apparatus using a second path through a surrounding wireless communication apparatus without passing through the arbitrary network A determination method is provided. Each of the plurality of gateway devices has route information to the one or more wireless communication devices to be connected to the arbitrary network, and the route determination method uses the wireless communication device as the arbitrary communication device. A gateway device to be connected to a network obtains the route information of another gateway device to which the other wireless communication device is to be connected to the arbitrary network via the arbitrary network; The other when the wireless communication device uses the first route based on the route information acquired from the other gateway device by the gateway device that is the connection target of the wireless communication device with the arbitrary network Acquiring the number of hops to the other wireless communication device and the other wireless communication when the second route is used. The step of obtaining the number of hops to the device, the number of hops of the first route, and the number of hops of the second route, using either the first route or the second route, Determining whether to communicate with another wireless communication device.

  As described above, according to the wireless communication device, the communication system, the program, and the route determination method according to the present invention, the communication route through the gateway device to another wireless communication device can be acquired more quickly.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

Further, the “best mode for carrying out the invention” will be described according to the following item order.
[1] Outline of communication system according to this embodiment [2] Background to this embodiment [3] Configuration of gateway [4] Configuration of wireless communication device [5] Operation of wireless communication device [6] Summary

[1] Overview of Communication System According to this Embodiment First, a communication system 1 according to this embodiment will be schematically described with reference to FIGS. 1 and 2.

  FIG. 1 and FIG. 2 are explanatory diagrams showing a configuration of the communication system 1 according to the present embodiment and a communication path in the communication system 1. As illustrated in FIG. 1, the communication system 1 includes a backbone network 12, a plurality of wireless communication devices 20A to 20F, and a plurality of gateways 22X to 22Z. In FIG. 1, in order to distinguish each wireless communication device, a capital letter is added after the reference numeral as in the wireless communication devices 20 </ b> A to 20 </ b> F, but it is not necessary to particularly distinguish each wireless communication device. In this case, the wireless communication device 20 is simply referred to collectively. Similarly, the gateways 22 </ b> X to 22 </ b> Z are simply collectively referred to as the gateway 22 when it is not necessary to distinguish each gateway.

  The backbone network 12 is a transmission path for messages transmitted from devices connected to the backbone network 12, and the transmission path may be wired or wireless. For example, the backbone network 12 may be a public line network such as the Internet, a telephone line network, a satellite communication network, and various types including Ethernet (registered trademark) IEEE (Institute of Electrical and Electronic Engineers) 802.11a, b, g, and n. LAN (Local Area Network) such as LAN (Local Area Network), WiMAX (World Wide Interoperability) planned for IEEE 802.16, etc., and IP-VPN (Internet VPN) Good.

  The gateway 22 connects the wireless multi-hop network including the backbone network 12 and the wireless communication devices 20A to 20F, and enables communication on the backbone network 12 and the wireless multi-hop network. Specifically, the gateway 22 converts the message transmitted from the wireless multi-hop network into a message for the backbone network 12 and transmits the converted message to the backbone network 12. Similarly, the gateway 22 converts the message received from the backbone network 12 into a message for a wireless multi-hop network, and transmits the converted data to the wireless multi-hop network wirelessly.

  Note that the gateway 22X has the wireless communication devices 20A, 20B, 20E, and 20F as connection targets to the backbone network 12, and the gateway 22X, the wireless communication devices 20A, 20B, 20E, and 20F form one subnetwork. . Similarly, the gateway 22Y uses the wireless communication devices 20C and 20D as connection targets to the backbone network 12, and the gateway 22Y and the wireless communication devices 20C and 20D form one subnetwork.

  The wireless communication device 20 can perform unicast for sending a message to a specific wireless communication device or flood communication. Here, the flooding communication is, for example, communication in which each wireless communication device 20 that has received a message including route information broadcasts the message and relays the message one after another. Such relaying by the wireless communication device 20 with a message may be expressed as a hop.

  In FIG. 1, the wireless communication device 20 is shown by a circle, but the wireless communication device 20 is a PC (Personal Computer), a home video processing device (DVD recorder, VCR, etc.), a mobile phone. , PHS (Personal Handyphone System), portable music playback device, portable video processing device, PDA (Personal Digital Assistants), home game device, portable game device, home appliance, etc. Good. Similarly to the wireless communication device 20, the gateway 22 may be an arbitrary information processing device as described above, or may be a router.

  Thus, in the communication system 1 according to this embodiment, the wireless multi-hop network and the backbone network 12 are connected by the gateway 22. Therefore, in the communication system 1 according to the present embodiment, communication is not limited to the communication path (second path) via only the wireless multi-hop network, and communication is also performed using the communication path (first path) via the backbone network 12. Can be done.

  For example, as illustrated in FIG. 1, the wireless communication device 20 </ b> A realizes communication with the gateway 22 </ b> Z connected to the backbone network 12 via the gateway 22 </ b> X that is the target of connection with the backbone network 12. be able to. Further, the radio communication device 20A can communicate with the radio communication device 20D forming the radio multi-hop network using the backbone network 12 via the gateway 22X and the gateway 22Y.

  In addition, as illustrated in FIG. 2, the wireless communication device 20B can perform communication using the backbone network 12 via the wireless communication device 20D forming the wireless multi-hop network, the gateway 22X, and the gateway 22Y. In this case, the number of hops is 2 because it is counted between the wireless communication device 20B and the gateway 22X and between the gateway 22Y and the wireless communication device 20D. Communication between the gateway X and the gateway 22Y may also be counted as the number of hops. Furthermore, the radio communication device 20B can communicate with the radio communication device 20D forming the radio multi-hop network via the radio communication device 20C without using the backbone network 12. In this case, the number of hops is 2 because it is counted between the wireless communication devices 20B and 20C and between the wireless communication devices 20C and 20D.

[2] Background to this embodiment Many of the general wireless networks represented by IEEE802.11b are limited by using a CSMA / CA access method that is a DCF (Distributed Coordination Function) in each wireless communication device. Communication is performed by sharing the wireless band with surrounding wireless communication devices.

  Therefore, as shown in FIG. 2, when there are a plurality of communication paths between the wireless communication devices 20B and 20D and the number of hops of the plurality of communication paths is the same, considering the wireless band of the wireless multi-hop network, It is desirable to use the backbone network 12.

  However, if the backbone network 12 is used in all communications, there is a concern that traffic is concentrated on a specific gateway and congestion occurs as shown in FIG.

  FIG. 3 is an explanatory diagram showing problems in the communication system 8 related to the present embodiment. As shown in FIG. 3, when the backbone network 12 is used in all communications, a tree-like network having the gateway 32X as a vertex is formed. As a result, messages transmitted from the wireless communication devices 30A, 30B, 30E, and 30F are concentrated on the gateway 32X, and there is a concern about the occurrence of traffic congestion.

  Therefore, the communication system 1 according to the present embodiment has been created by focusing on the above-described circumstances. According to the communication system 1 according to the present embodiment, communication via the backbone network 12 can be realized while suppressing the concentration of traffic on the gateway 22 by appropriately selecting a communication path. Hereinafter, the configuration of the gateway 22 and the wireless communication device 20 configuring the communication system 1 will be described in detail with reference to FIGS. 4 to 13.

[3] Configuration of Gateway FIG. 4 is an explanatory diagram showing a hardware configuration of the gateway 22 according to the present embodiment. As shown in FIG. 4, the gateway 22 includes a CPU (Central Processing Unit) 201, a ROM (Read Only Memory) 202, a RAM (Random Access Memory) 203, a host bus 204, a bridge 205, and an external bus. 206, an interface 207, an input device 208, an output device 210, a storage device (HDD) 211, a drive 212, and a communication device 215.

  The CPU 201 functions as an arithmetic processing device and a control device, and controls the overall operation in the gateway 22 according to various programs. Further, the CPU 201 may be a microprocessor. The ROM 202 stores programs used by the CPU 201, calculation parameters, and the like. The RAM 203 primarily stores programs used in the execution of the CPU 201, parameters that change as appropriate during the execution, and the like. These are connected to each other by a host bus 204 including a CPU bus.

  The host bus 204 is connected to an external bus 206 such as a PCI (Peripheral Component Interconnect / Interface) bus via a bridge 205. Note that the host bus 204, the bridge 205, and the external bus 206 are not necessarily configured separately, and these functions may be mounted on one bus.

  The input device 208 is, for example, an input means for a user to input information, such as a mouse, keyboard, touch panel, button, microphone, switch, and lever, and an input that generates an input signal based on the input by the user and outputs the input signal to the CPU 201 It consists of a control circuit. A user of the gateway 22 can input various data and instruct a processing operation to the gateway 22 by operating the input device 208.

  The output device 210 includes, for example, a display device such as a CRT (Cathode Ray Tube) display device, a liquid crystal display (LCD) device, an OLED (Organic Light Emitting Display) device and a lamp, and an audio output device such as a speaker and headphones. The The output device 210 outputs reproduced content, for example. Specifically, the display device displays various information such as reproduced video data as text or images. On the other hand, the audio output device converts reproduced audio data or the like into audio and outputs it.

  The storage apparatus 211 is a data storage apparatus configured as an example of a storage unit of the gateway 22 according to the present embodiment. The storage device 211 may include a storage medium, a recording device that records data on the storage medium, a reading device that reads data from the storage medium, a deletion device that deletes data recorded on the storage medium, and the like. The storage device 211 is composed of, for example, an HDD (Hard Disk Drive). The storage device 211 drives a hard disk and stores programs executed by the CPU 201 and various data. Further, the storage device 211 records a network route table, a sub-network table, and the like which will be described later.

  The drive 212 is a storage medium reader / writer, and is built in or externally attached to the gateway 22. The drive 212 reads information recorded on a removable storage medium 24 such as a mounted magnetic disk, optical disk, magneto-optical disk, or semiconductor memory, and outputs it to the RAM 203.

  The communication device 215 is a communication interface including, for example, a communication device for connecting to the backbone network 12 and the wireless communication device 20. The communication device 215 may be a wireless LAN (Local Area Network) compatible communication device, a wireless USB compatible communication device, or a wire communication device that performs wired communication. The communication device 215 transmits / receives various data to / from the backbone network 12 and the wireless communication device 20.

  Although the hardware configuration of the gateway 22 has been described above with reference to FIG. 4, the hardware of the wireless communication device 20 can be configured substantially the same as the gateway 22, and thus the description thereof is omitted. .

  Next, the function of the gateway 22 according to the present embodiment will be described with reference to FIG.

  FIG. 5 is a functional block diagram showing the configuration of the gateway 22 according to the present embodiment. As shown in FIG. 5, the gateway 22 includes a communication unit 216, a notification signal generation unit 220, a sub-network table creation unit 224, a storage unit 228, an external table acquisition unit 232, and a network route table creation unit 236. And a request response unit 240.

  The communication unit 216 is an interface with the backbone network 12 and the wireless communication device 20, and functions as a transmission unit and a reception unit that transmit and receive various types of information to and from the backbone network 12 and the wireless communication device 20. For example, the communication unit 216 down-converts a high-frequency radio signal transmitted from the radio communication device 20 into a baseband signal, and converts the baseband signal into a bit string. The communication unit 216 wirelessly broadcasts the gateway notification signal generated by the notification signal generation unit 220.

  Note that the communication unit 216 may have a wireless communication function defined in IEEE802.11a, b, g, etc., or a MIMO (Multiple Input Multiple Output) communication function defined in IEEE802.11n. Also good. Further, the communication unit 216 may have a communication function corresponding to WiMAX planned for IEEE 802.16.

  The notification signal generation unit 220 generates a gateway notification signal (beacon) for transmission to the wireless communication device 20 in a predetermined period within the sub-network of the gateway 22. The gateway notification signal includes, for example, a network route table (described later) generated by the network route table creation unit 236.

  The sub-network table creation unit 224 creates a sub-network table that includes information related to the wireless communication device 20 that recognizes or selects the self-device as a gateway. For example, when a gateway recognition notification signal indicating that a certain wireless communication device 20 recognizes its own device as a gateway is received, the subnetwork table creation unit 224 displays path information regarding the wireless communication device 20 as a subnetwork table. Register with. A specific example will be described below with reference to FIGS.

  FIG. 6 is an explanatory diagram showing how a sub-network is formed. FIG. 7 is an explanatory diagram showing a specific example of the sub-network table. For example, as shown in FIG. 6, the wireless communication devices 20A, 20B, 20E, and 20F recognize the gateway 22X, and the gateway 22X receives the gateway recognition notification signal from the wireless communication devices 20A, 20B, 20E, and 20F. And Then, the sub-network table creation unit 224 creates a sub-network table as shown in FIG. 7A, and the radio communication devices 20A, 20B, 20E, 20F and the gateway 22X form the sub-network 3.

  As shown in FIG. 7A, the sub-network table first indicates to which wireless communication device the message is transmitted as the next hop device when the message is transmitted from the gateway 22 to another wireless communication device. Includes the number of hops to the wireless communication device. Here, in this specification, for convenience of explanation, it is assumed that an alphabet added after a symbol indicating each device corresponds to an address of the device. For example, in this specification, it is assumed that the address of the gateway 22X is X and the address of the wireless communication device 20A is A. Therefore, in FIG. 7A, when the gateway 22X transmits a message to the wireless communication device 20A whose address is A, the message is transmitted to the wireless communication device 20A as the next hop device, and the number of hops to the wireless communication device 20A is 1. It shows that there is.

  Similarly, it is assumed that the wireless communication devices 20C and 20D recognize the gateway 22Y, and the gateway 22Y receives the gateway recognition notification signal from the wireless communication devices 20C and 20D. Then, the sub-network table creation unit 224 of the gateway 22Y creates a sub-network table as shown in FIG. 7B, and the wireless communication devices 20C and 20D and the gateway 22Y form the sub-network 4.

  Specifically, as illustrated in FIG. 7B, the sub-network table creation unit 224 of the gateway 22Y has the wireless communication device 20C as the next hop device when transmitting a message to the wireless communication device 20C, and the hop count is 1. Create a sub-network table indicating that The subnetwork table also includes the fact that the next hop device when transmitting a message from the gateway 22Y to the wireless communication device 20D is the wireless communication device 20D and the hop count is 1.

  The storage unit 228 is a storage medium on which the subnetwork table created by the subnetwork table creation unit 224 and the network route table described later are recorded. Such a storage unit 228 includes, for example, a nonvolatile memory such as an EEPROM (Electrically Erasable Programmable Read-Only Memory) and an EPROM (Erasable Programmable Read Only Memory), a magnetic disk such as a hard disk and a disk type magnetic disk, and the like. -R (Compact Disc Recordable) / RW (ReWriteable), DVD-R (Digital Versatile Disc Recordable) / RW / + R / + RW / RAM (Random Access Memory) and BD (Blu-R) (trademark) Optical discs such as BD-RE, MO (Magnet Optical) may be a storage medium such as a disk.

  The external table acquisition unit 232 acquires a subnetwork table of another subnetwork created by the other gateway 22Y and records it in the storage unit 228. For example, the external table acquisition unit 232 may request the other gateway 22Y to transmit the subnetwork table and acquire the subnetwork table transmitted from the other gateway 22Y in response to the request. Alternatively, another gateway 22Y or the like periodically transmits a subnetwork table of its own device via the backbone network 12, and the external table acquisition unit 232 acquires the subnetwork table periodically transmitted in this way. May be.

  The network route table creation unit 236 creates a network route table based on the sub network table recorded in the storage unit 228. Specifically, the network as shown in FIG. 8 is obtained by integrating the subnetwork table of the own device created by the subnetwork table creation unit 224 and the other subnetwork table acquired by the external table acquisition unit 232. Create a route table.

  FIG. 8 is an explanatory diagram showing a specific example of the network route table. More specifically, FIG. 8 shows a network route table created based on the sub-network table shown in FIGS. 7A and 7B.

  As shown in FIG. 8, the network route table creation unit 236 adds the address (X) of its own device as a gateway to the sub-network table of its own device created by the sub-network table creation unit 224, thereby adding the network route table. Register as Further, the network route table creation unit 236 adds the address (Y) of the gateway 22Y to the other subnetwork table acquired from the other gateway 22Y by the external table acquisition unit 232 and registers it as a network route table.

  Such a network route table is recorded in the storage unit 228 and updated as necessary. In the storage unit 228, route information from the own device to the wireless communication device 20 existing within, for example, two hops is also recorded as a local route table as shown in FIG. 9, for example.

  FIG. 9 is an explanatory diagram showing a specific example of the local route table. More specifically, FIG. 9A shows a local route table generated by the gateway 22X, and FIG. 9B shows a local route table generated by the gateway 22Y. The local route table is common to the subnetwork table in that it includes the next hop device and the number of hops when transmitting a message to another wireless communication device 20. On the other hand, the local route table differs from the sub-network table in that it includes information up to the wireless communication device 20 existing within, for example, two hops regardless of whether or not it is included in the sub-network.

  For example, as illustrated in FIG. 9A, the subnetwork table of the gateway 22X does not include information related to the wireless communication device 20C, but the local route table of the gateway 22X includes information related to the wireless communication device 20C. Similarly, as illustrated in FIG. 9B, the subnetwork table of the gateway 22Y does not include information related to the wireless communication device 20B, but the local route table of the gateway 22Y includes information related to the wireless communication device 20B. . Note that the gateway 22 transmits a response request to the wireless communication device 20 existing within two hops, and receives a response to the response request from the wireless communication device 20, whereby the wireless communication device existing within two hops. Up to 20 pieces of information may be acquired. Alternatively, when a notification signal is periodically transmitted from the wireless communication device 20, the gateway 22 may acquire information regarding the wireless communication device 20 by receiving the notification signal.

  Here, returning to the description of the configuration of the gateway 22 with reference to FIG. 5, the request response unit 240 performs processing in response to various requests from the outside. For example, when there is a subnetwork table acquisition request from another gateway 22Y via the backbone network 12, the subnetwork table is read from the storage unit 228 and transmitted to the other gateway 22Y. Alternatively, when there is a network route table acquisition request from the wireless communication device 20, the request response unit 240 reads the network route table from the storage unit 228 and transmits it to the wireless communication device 20.

  Further, when there is an acquisition request for the number of hops from the wireless communication device 20 to the specific wireless communication device, the request response unit 240 calculates the number of hops to the specific wireless communication device based on the network route table. The number of hops may be transmitted to the requesting wireless communication device 20. Specifically, the request response unit 240 searches the network route table for the gateway and the number of hops associated with the destination of the specific wireless communication device.

  If the gateway associated with the destination of the specific wireless communication device is not the own device, the requesting wireless communication device 20 automatically sets the number of hops associated with the destination of the specific wireless communication device. Add the number of hops to the device. Then, the request response unit 240 transmits the addition result to the requesting wireless communication device 20. As a result, the requesting wireless communication device 20 can acquire the number of hops when the backbone network 12 from the requesting wireless communication device 20 to the specific wireless communication device is used.

[4] Configuration of Wireless Communication Device The configuration of the gateway 22 according to the present embodiment has been described above with reference to FIGS. Next, the configuration of the wireless communication device 20 according to the present embodiment will be described with reference to FIGS.

  FIG. 10 is a functional block diagram showing the configuration of the wireless communication device 20 according to the present embodiment. As illustrated in FIG. 10, the wireless communication device 20 includes a communication unit 256, a gateway registration processing unit 260, a storage unit 264, a route table creation unit 268, a comparison table creation unit 272, and a determination unit 276. A transmission data generation unit 280.

  The communication unit 256 is an interface with the backbone network 12 and other wireless communication devices 20B, and serves as a transmission unit and a reception unit that transmit and receive various types of information to and from the backbone network 12 and other wireless communication devices 20B. It has a function. For example, the communication unit 256 down-converts a high-frequency radio signal transmitted from the radio communication device 20 or the gateway 22 into a baseband signal, and converts the baseband signal into a bit string. The communication unit 256 broadcasts the message generated by the transmission data generation unit 280 wirelessly.

  Note that the communication unit 256 may have a wireless communication function defined in IEEE802.11a, b, g, or the like, as in the communication unit 216 of the gateway 22, or a MIMO communication function defined in IEEE802.11n. You may have. The communication unit 256 may have a communication function corresponding to WiMAX planned for IEEE 802.16.

  The gateway registration processing unit 260 selects the gateway 22 to be used when connecting to the backbone network 12 and records it in the storage unit 264. An example of a method for selecting the gateway 22 will be described below.

  First, the gateway registration processing unit 260 adds the gateway 22 that is the transmission source of the gateway notification signal periodically transmitted from each gateway 22 received by the communication unit 256 to the gateway list. Then, the gateway registration processing unit 260 selects the gateway having the shortest hop number from among the gateways 22 registered in the gateway list as the gateway of its own device.

  In addition, when the gateway notification signal is received and the gateway of the transmission source of the gateway notification signal does not exist in the gateway list, the gateway registration processing unit 260 newly adds information of the transmission source gateway to the gateway list. Then, when the gateway list is updated, the gateway registration processing unit 260 selects the gateway with the shortest hop count as the gateway of the own device.

  The gateway registration processing unit 260 also updates the gateway when an individual route table described later is updated. Thus, by appropriately updating the gateway, it is possible to flexibly cope with changes in the situation of the wireless multi-hop network.

  Furthermore, when the gateway registration processing unit 260 selects a gateway, the gateway registration processing unit 260 transmits a gateway recognition notification signal from the communication unit 256 to the selected gateway. With this configuration, the gateway 22 can recognize the wireless communication device 20 that has selected the gateway 22. The gateway registration processing unit 260 may transmit a gateway recognition notification signal at a predetermined cycle, or may transmit it in response to a request from the gateway 22. Such a notification method can be implemented according to the routing protocol to be used, and the overhead required for notification can be reduced.

  In the present embodiment, any routing protocol such as a proactive type, a reactive type, or a hybrid type can be used.

  The storage unit 264 is a storage medium in which various types of information such as a gateway list, an individual route table, and a comparison table are recorded. Similar to the storage unit 228 of the gateway 22, the storage unit 264 is a nonvolatile memory such as an EEPROM or EPROM, a magnetic disk such as a hard disk or a disk-type magnetic disk, a CD-R / RW, or a DVD-R / RW. It may be an optical disc such as / + R / + RW / RAM and BD (Blu-Ray Disc (registered trademark))-R / BD-RE, or a storage medium such as an MO disc.

  The route table creation unit 268 has a function as a second hop number acquisition unit that creates an individual route table indicating a route from its own device to another wireless communication device and records it in the storage unit 264. The route table creation unit 268 can acquire a route from the own device to another wireless communication device using an arbitrary routing protocol. For example, the route table creation unit 268 may acquire a route to another wireless communication device by transmitting a route request and receiving a route reply for the route request. A specific example of the individual route table created by the route table creation unit 268 is shown in FIG.

  FIG. 11 is an explanatory diagram showing a specific example of the individual route table. More specifically, FIG. 11 shows an individual route table created by the route table creation unit 268 of the wireless communication device 20A. Since the message transmitted by the wireless communication device 20A first passes through the wireless communication device 20B and then reaches the wireless communication device 20D via the wireless communication device 20C, the next hop device as shown in FIG. The wireless communication device 20B has a hop count of 3. Similarly, the radio communication device 20A can communicate with the gateway 22X in one hop without going through other devices.

  The comparison table creation unit 272 creates a comparison table for comparing a plurality of communication routes based on the network route table created by the gateway 22 and the individual route table created by the route table creation unit 268. Function as a hop count acquisition unit. In the following, the case where the network route table is periodically transmitted from the gateway 22 by flooding will be described with reference to FIG.

  FIG. 12 is an explanatory diagram showing a specific example of the comparison table created by the comparison table creation unit 272. First, the comparison table creation unit 272 registers a route that can be communicated only with the wireless multi-hop network in the comparison table in the form that there is no gateway. Specifically, as shown in the upper part of FIG. 12, 0 is described in the gateway corresponding to the wireless communication device 20D. Information about the wireless communication device 20D can be created from the individual route table.

  On the other hand, the comparison table creation unit 272 registers a route using the backbone network 12 in the comparison table using the individual route table shown in FIG. 11 and the network route table shown in FIG. To do. For example, the comparison table creation unit 272 first searches the individual route table managed by the routing protocol for the route to the gateway 22X selected by the wireless communication device 20A.

  Then, when there is a route to the gateway 22X, the comparison table creation unit 272 searches the network route table for information related to the wireless communication device 20D that is a route search target. If information related to the wireless communication device 20D exists and the gateway selected by the wireless communication device 20D is different from the gateway X being selected by the own device, the wireless communication device 20D is included in a different subnetwork from the own device. to decide.

  Further, the comparison table creation unit 272 describes X, which is the address of the gateway 22X being selected, as the address of the next hop device, and also describes X, which is the address of the gateway 22X being selected, in the gateway address. sign up. Further, the comparison table creation unit 272 adds (1 + 1) the number of hops between the wireless communication device 20A and the gateway 22X and the number of hops between the gateway 22Y and the wireless communication device 20D to be searched from the network route table information. Register in the comparison table. The comparison table creation unit 272 may acquire the number of hops between the wireless communication device 20A and the gateway 22X from the individual route table and use it for the calculation.

  In this way, a comparison table including the number of hops for both the route via the wireless multi-hop network and the route via the backbone network 12 as shown in FIG. 12 is obtained.

  Next, a case where a route search message is transmitted from the wireless communication device 20 to the gateway 22 will be described. When receiving the route search message from the wireless communication device 20, the request response unit 240 of the gateway 22 refers to the network route table and searches the network route table for information regarding the wireless communication device 20 to be searched. Then, when there is information on the search target wireless communication device 20 and the route search source wireless communication device 20 is different from the gateway 22 being selected by the search target wireless communication device 20, the request response unit 240 acts as a proxy. As a response, a response message is returned to the route search source.

  Here, consider a case where a route search message transmitted from the wireless communication device 20A as a route search source reaches the gateway 22X with a hop count of one. In this case, the response message returned by the gateway 22X includes the number of hops (1) from the wireless communication device 20A to the gateway 22X as the hop number (distance) to the route search wireless communication device 20D and the wireless communication from the gateway 22Y. The hop count (2) obtained by adding the hop count (1) to the communication device 20D is described. The wireless communication device 20A as a route search source registers the contents described in the response message in the comparison table, thereby creating a comparison table including route information of a plurality of routes shown in FIG.

  If the search target wireless communication device 20 exists in the network route table, but the selected gateway 22 is the same between the route search source wireless communication device 20 and the search target wireless communication device, the gateway 22 acts as a proxy. You do not have to respond.

  The determination unit 276 determines, based on the comparison table created by the comparison table creation unit 272, whether to use a route that passes only through the wireless multi-hop network or a route that passes through the backbone network 12. At this time, the determination unit 276 determines the communication path in consideration of the traffic amount and data type of transmission data, and details will be described later with reference to FIGS. 16 and 17.

  The transmission data generation unit 280 generates transmission data including arbitrary data in which the device corresponding to the communication path determined by the determination unit 276 is the next hop device. Optional data includes music data such as music, lectures and radio programs, video data such as movies, television programs, video programs, photographs, documents, pictures and charts, games and software, etc. .

[5] Operation of Wireless Communication Device The configuration of the wireless communication device 20 and the gateway 22 has been described above. Next, operations such as a route determination method executed in the wireless communication device 20 according to the present embodiment will be described.

  FIG. 13 is a flowchart showing the flow of the gateway registration process. As shown in FIG. 13, first, when the wireless communication apparatus 20 receives a gateway notification signal (S304), the gateway registration processing unit 260 determines whether the gateway 22 that is the transmission source of the gateway notification signal is registered in the gateway list. It is determined whether or not (S308). If the transmission source gateway 22 is not registered in the gateway list, the gateway registration processing unit 260 newly registers the transmission source gateway 22 in the gateway list (S312).

  Subsequently, the gateway registration processing unit 260 determines whether or not the transmission source gateway 22 is registered in the individual route table (S316). Then, when the transmission source gateway 22 is registered in the individual route table and the number of hops is the shortest compared to other gateways, it is selected as the gateway of its own device (S320).

  FIG. 14 is a flowchart showing the flow of the gateway update process. As shown in FIG. 14, when the individual route table is updated (S350), the gateway registration processing unit 260 determines whether or not the information related to the gateway registered in the gateway list is updated (S354).

  When the information related to the gateway registered in the gateway list is updated, the gateway registration processing unit 260 selects the gateway with the shortest hop number as the gateway of the own device (S358).

  FIG. 15 is a flowchart showing the flow of the comparison table creation process. Here, a flow in the case where the wireless communication device 20D is a route search target is shown. First, when information related to the wireless communication device 20D exists in the individual route table (S404), the comparison table creation unit 272 adds a gateway address of “0” to the information and registers it in the comparison table (S408).

  Subsequently, when the network route table is received from the gateway 22 by the communication unit 256, the comparison table creating unit 272 determines whether or not the information given to the gateway X that is the selected gateway exists in the network route table. (S416). That is, it is determined whether the own apparatus is included in the sub-network of the gateway 22X. Here, the comparison table creating unit 272 may proceed to the process of S420 only when the information regarding the gateway 22X is also included in the individual route table.

  Further, the comparison table creating unit 272 determines whether or not the information regarding the wireless communication device 20D is included in the network route table (S420). Then, the comparison table creation unit 272 includes information related to the wireless communication device 20D in the network route table, and the wireless communication device 20D selects a gateway different from the gateway 22X that is selected by the own device. The number of hops is added and registered in the comparison table (S428). More specifically, the comparison table creating unit 272, based on the network route table, the number of hops from the wireless communication device 20 to the gateway 22X, and the number of hops from the gateway selected by the wireless communication device 20D to the wireless communication device 20D. Is added.

  16 and 17 are flowcharts showing the flow of route selection processing. The determining unit 276 refers to the comparison table and determines whether there are a plurality of routes to the target wireless communication device 20 (S504). Then, when there are no multiple paths, the determination unit 276 selects an existing path as a communication path (S508).

  On the other hand, when there are a plurality of routes, the determination unit 276 determines whether or not the difference in the number of hops of the plurality of routes is a predetermined value or more (S512). Then, when the difference in the number of hops of the plurality of routes is greater than or equal to the predetermined value, the determining unit 276 selects the route having the smaller number of hops as the communication route (S516). On the other hand, when the difference in the number of hops is smaller than the predetermined value, the determination unit 276 performs route selection in consideration of the data contents shown in FIG. 17 (S520).

In route selection considering data contents, first, as shown in FIG. 17, the determination unit 276 confirms the traffic amount of transmission data (S554). Then, when the traffic amount is equal to or larger than the reference amount (S558), the determination unit 276 selects a route using the backbone network 12 (S562). The reference amount may be a static value such as a half value of the maximum traffic amount supported by the wireless communication device 20, or a dynamic value that changes according to the network status.

On the other hand, when the traffic amount is less than the reference amount, the determination unit 276 confirms the type and priority of the transmission data (S566). Then, the determination unit 276 determines whether to use the backbone network 12 based on the type and priority of transmission data (S570). For example, the determination unit 276 may determine to use the backbone network 12 for transmission data that needs to be reliably transmitted to a destination, such as streaming data or high priority data. Further, the determination unit 276 may consider whether the transmission data is audio data or video data as the type of transmission data.

[6] Summary As described above, in the present embodiment, the number of hops to the other wireless communication device 20 when the backbone network 12 is used is the gateway 22 whose own device is a connection target with an arbitrary network. Is acquired based on the route information acquired from the other gateway 22. Accordingly, since the wireless communication device 20 does not need to actually search for a route to the other wireless communication device 20 via the backbone network 12, the number of hops to the other wireless communication device 20 when the backbone network 12 is used. Can be acquired earlier. As a result, the determination unit 276 can efficiently determine the communication route based on the number of hops of each of the plurality of routes.

  Further, according to the present embodiment, the traffic concentration in the gateway 22 can be distributed to some extent. As a result, for example, when considering a network that assumes moving image distribution, it is possible to control a stream of moving images or the like so that there is room in the wireless band of the entire wireless multihop network by using the backbone network 12 as much as possible. . On the other hand, with respect to highly important data such as control information and relatively low traffic data, it is possible to handle data according to the priority of data, such as using only a wireless multi-hop network with a sufficient wireless bandwidth.

  Furthermore, since the wireless communication device 20 according to the present embodiment holds a plurality of routes, communication can be quickly performed when a communication state such as a wireless link state changes or when a failure occurs in the gateway 22. It is possible to switch routes. This makes it possible to construct a wireless multi-hop network that is robust against network changes and failures.

  In addition, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the example which concerns. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  For example, each step in the processing of the wireless communication device 20 of the present specification does not necessarily have to be processed in time series in the order described as a flowchart. For example, each step in the processing of the wireless communication device 20 may include processing executed in parallel or individually (for example, parallel processing or object processing).

  It is also possible to create a computer program for causing hardware such as the CPU 201, the ROM 202, and the RAM 203 built in the wireless communication device 20 and the gateway 22 to perform the same functions as the components of the wireless communication device 20 and the gateway 22 described above. It is. A storage medium storing the computer program is also provided. Moreover, a series of processing can also be realized by hardware by configuring each functional block shown in the functional block diagram of FIG. 5 with hardware. Similarly, a series of processing can be realized by hardware by configuring each functional block shown in the functional block diagram of FIG. 10 with hardware.

It is explanatory drawing which showed the structure of the communication system concerning this embodiment, and the communication path | route in a communication system. It is explanatory drawing which showed the structure of the communication system concerning this embodiment, and the communication path | route in a communication system. It is explanatory drawing which showed the problem in the communication system relevant to this embodiment. It is explanatory drawing which showed the hardware constitutions of the gateway concerning this embodiment. It is the functional block diagram which showed the structure of the gateway concerning this embodiment. It is explanatory drawing which showed a mode that a subnetwork was formed. It is explanatory drawing which showed the specific example of the subnetwork table. It is explanatory drawing which showed the specific example of the subnetwork table. It is explanatory drawing which showed the specific example of the network route table. It is explanatory drawing which showed the specific example of the local route table. It is explanatory drawing which showed the specific example of the local route table. It is the functional block diagram which showed the structure of the radio | wireless communication apparatus concerning this embodiment. It is explanatory drawing which showed the specific example of the separate path | route table. It is explanatory drawing which showed the specific example of the comparison table produced by the comparison table preparation part. It is the flowchart which showed the flow of the gateway registration process. It is the flowchart which showed the flow of the gateway update process. It is the flowchart which showed the flow of the preparation process of a comparison table. It is the flowchart which showed the flow of the route selection process. It is the flowchart which showed the flow of the route selection process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Communication system 12 Backbone network 20 Wireless communication apparatus 22 Gateway 216, 256 Communication part 220 Notification signal generation part 224 Subnetwork table creation part 228, 264 Storage part 232 External table acquisition part 236 Network route table creation part 240 Request response part 260 Gateway Registration processing unit 268 Route table creation unit 272 Comparison table creation unit 276 Judgment unit

Claims (9)

A first route that passes through an arbitrary network and a plurality of gateway devices that connect one or more wireless communication devices and the arbitrary network, or a second route that passes through the surrounding wireless communication device without passing through the arbitrary network A wireless communication device that communicates with other wireless communication devices using a path:
Each of the plurality of gateway devices has route information to the one or more wireless communication devices to be connected to the arbitrary network, and further connects the wireless communication device to the arbitrary network. The target gateway device acquires the route information of the other gateway device whose connection target is the other wireless communication device with the arbitrary network via the arbitrary network,
The wireless communication device
Based on the route information acquired from the other gateway device by the gateway device to be connected to the arbitrary network, the wireless communication device is connected to the other wireless communication device when the first route is used. A first hop number acquisition unit for acquiring a hop number;
A second hop number acquisition unit for acquiring the number of hops to the other wireless communication device when the second route is used;
The first route according to the hop number of the first route acquired by the first hop number acquisition unit and the hop number of the second route acquired by the second hop number acquisition unit. A determination unit that determines which of the second route is used to communicate with the other wireless communication device;
With
Each of the communication devices constituting the arbitrary network is connected by wire,
The determination unit is configured such that a difference between the number of hops of the first route and the number of hops of the second route is less than a predetermined value, and a bandwidth of transmission data to the other wireless communication device is equal to or greater than a reference value If so, a wireless communication device that determines to communicate with the other wireless communication device using the first route .   When the difference between the number of hops of the first route and the number of hops of the second route is equal to or greater than a predetermined value, the determination unit uses the route with the smaller number of hops to use the other wireless communication. The wireless communication apparatus according to claim 1, wherein the wireless communication apparatus determines to communicate with the apparatus. The determination unit is configured such that a difference between the number of hops of the first route and the number of hops of the second route is less than a predetermined value , and a band of transmission data to the other wireless communication device is less than a reference value If it is, it is determined which of the first route and the second route is used to communicate with the other wireless communication device according to the data type of the transmission data. The wireless communication apparatus according to claim 2.   The wireless communication device further includes a receiving unit that receives route information acquired by the gateway device from a gateway device that connects the wireless communication device and the arbitrary network. The wireless communication device described.   The first hop number acquisition unit determines the number of hops from the other gateway device to the other wireless communication device included in the route information received by the reception unit, and the wireless communication device and the arbitrary network. The number of hops to the other wireless communication device when the first route is used is obtained by adding the number of hops to the gateway device that connects to the wireless communication device according to claim 5. Wireless communication device.   The first hop number acquisition unit requests the gateway device that connects the wireless communication device and the arbitrary network to acquire the hop number to the other wireless communication device, and the gateway device acquires the other hop number. The wireless device according to claim 1, wherein the number of hops to the other wireless communication device obtained in the gateway device based on the route information obtained from the gateway device is obtained from the gateway device. Communication device. A plurality of gateway devices that connect an arbitrary network and one or more wireless communication devices, a first route that passes through the plurality of gateway devices and the arbitrary network, or a surrounding radio that does not pass through the arbitrary network A wireless communication device that communicates with other wireless communication devices using a second path through the communication device, comprising:
Each of the plurality of gateway devices has route information to the one or more wireless communication devices to be connected to the arbitrary network, and further connects the wireless communication device to the arbitrary network. The target gateway device acquires the route information of the other gateway device whose connection target is the other wireless communication device with the arbitrary network via the arbitrary network,
The wireless communication device
Based on the route information acquired from the other gateway device by the gateway device to be connected to the arbitrary network, the wireless communication device is connected to the other wireless communication device when the first route is used. A first hop number acquisition unit for acquiring a hop number;
A second hop number acquisition unit for acquiring the number of hops to the other wireless communication device when the second route is used;
The first route according to the hop number of the first route acquired by the first hop number acquisition unit and the hop number of the second route acquired by the second hop number acquisition unit. A determination unit that determines which of the second route is used to communicate with the other wireless communication device;
With
Each of the communication devices constituting the arbitrary network is connected by wire,
The determination unit is configured such that a difference between the number of hops of the first route and the number of hops of the second route is less than a predetermined value, and a bandwidth of transmission data to the other wireless communication device is equal to or greater than a reference value If so , a communication system that determines to communicate with the other wireless communication device using the first route . An arbitrary network composed of communication devices connected by wire and one or two or more wireless communication devices are connected, route information to the one or two or more wireless communication devices is included, and another gateway device has Using a first route through the gateway device that acquires the route information through the arbitrary network and the arbitrary network, or a second route through a surrounding wireless communication device without passing through the arbitrary network A computer provided in a wireless communication device that communicates with other wireless communication devices
Based on route information acquired from another gateway device connecting the other wireless communication device and the arbitrary network by the gateway device connecting the wireless communication device and the arbitrary network, the first route is changed. A first hop number acquisition unit that acquires the number of hops to the other wireless communication device when used;
A second hop number acquisition unit for acquiring the number of hops to the other wireless communication device when the second route is used;
The difference between the hop number of the first route acquired by the first hop number acquisition unit and the hop number of the second route acquired by the second hop number acquisition unit is less than a predetermined value. When the bandwidth of the transmission data to the other wireless communication device is equal to or greater than a reference value, it is determined that communication with the other wireless communication device is performed using the first route. When;
Program to function as A plurality of gateway devices that connect an arbitrary network and one or more wireless communication devices, a first route that passes through the plurality of gateway devices and the arbitrary network, or a surrounding radio that does not pass through the arbitrary network A route determination method executed in a wireless communication device that communicates with another wireless communication device using a second route through the communication device:
Each of the plurality of gateway devices has path information to the one or more wireless communication devices that are to be connected to the arbitrary network, and the wireless communication device is connected to the arbitrary network. A gateway device that obtains the route information of another gateway device that uses the other wireless communication device as a connection target with the arbitrary network via the arbitrary network;
The wireless communication device is
Based on the route information acquired from the other gateway device by the gateway device to be connected to the arbitrary network, the wireless communication device is connected to the other wireless communication device when the first route is used. Obtaining a hop count;
Obtaining the number of hops to the other wireless communication device when using the second route;
When the difference between the number of hops of the first route and the number of hops of the second route is less than a predetermined value, and the bandwidth of transmission data to the other wireless communication device is a reference value or more, Determining to communicate with the other wireless communication device using the first path ;
A route determination method characterized by comprising:

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