JP6326736B2 - Relay device, relay method, and relay program - Google Patents

Description

  The present invention relates to a relay device, a relay method, and a relay program.

  In recent years, wireless communication using an ad hoc network system is attracting attention in mobile phones and portable game machines. An ad hoc network system is a system in which, for example, a communication device such as a mobile phone autonomously performs routing without going through a base station or an access point, thereby enabling wireless communication between the communication devices. In an ad hoc network system, for example, a base station and an access point are not required, and thus a network can be easily constructed even in a place where such an infrastructure does not exist.

  In an ad hoc network system, for example, wireless communication may be performed via a relay device such as a router. Thereby, for example, even when the communication devices are separated from each other by a certain distance or more, wireless communication between the communication devices can be performed via the relay device.

  In such an ad hoc network system, for example, a broadcast packet may be transmitted. The broadcast packet is, for example, packet data in which the same information is simultaneously transmitted to an unspecified number. By transmitting the broadcast packet, for example, setting information can be transmitted to each communication device. For example, the communication device can perform various settings based on the setting information. In this case, for example, when the relay device receives a broadcast packet, the relay device unconditionally transmits the received packet data.

  As a technique related to the ad hoc network system, for example, there are the following techniques. That is, there is a technique in which each station STA to STD transmits a multicast packet having an ACK function to another station when receiving data transmitted by the multicast packet.

  According to this technology, for example, efficient communication by multicast communication is possible, and power saving of the communication terminal device can be realized.

JP 2009-176163 A

  However, in the ad hoc network system, as described above, the relay device transmits a broadcast packet unconditionally, for example. Thereby, for example, in an ad hoc network system, the degree of occupation of the communication band may increase beyond a certain level. This point will be described below.

  FIG. 14 is a diagram illustrating a configuration example of an ad hoc network system 550 including relay apparatuses (#X to #Z) 500-X to 500-Z.

  When the relay device 500-X receives the broadcast packet, the relay device 500-X broadcasts the received broadcast packet unconditionally. Further, when the relay device 500-Y receives the broadcast packet transmitted from the relay device 500-X, the relay device 500-Y broadcasts the received broadcast packet unconditionally. Further, when receiving the broadcast packet transmitted from the relay device 500-Y, the relay device 500-Z broadcasts the received broadcast packet unconditionally.

  In this case, the relay device 500-Y may receive the same broadcast packet as the broadcast packet transmitted from the relay device 500-X from the relay device 500-Z. Therefore, as compared with the case where the relay apparatus 500-Y receives the packet from one relay apparatus 500-X, the transmission opportunity of the packet data transmitted in the wireless section is increased, and the occupation rate of the communication band is increased. .

  The above-described technique for providing an ACK function to a multicast packet is, for example, a technique for a multicast packet, not a broadcast packet. Further, in this technique, for example, when each station receives a multicast packet transmitted from another station, the station transmits the multicast packet to which the ACK is added to the other station. Therefore, in the above-described technique, there are two transmission opportunities in the wireless section because a multicast packet is transmitted from each station and a multicast packet with an ACK added to the multicast packet is transmitted. Therefore, in the above-described technique, the transmission opportunities in the radio section are increased and the communication band is occupied as compared to the case where the multicast packet is transmitted with one transmission opportunity or the case where there is no transmission opportunity of the multicast packet itself. The degree is increasing.

  In one aspect, an object is to reduce the degree of occupation of a communication band.

  In one aspect, a relay device that transmits received packet data to a communication device that is a transmission destination of the packet data, receives a plurality of packet data transmitted by broadcast, and receives the plurality of received packet data. Among them, the transmission unit that transmits packet data to which a response request is added by broadcast and the result of determining the presence / absence of the response according to the result of determining the presence / absence of the response transmitted from the communication device with respect to the response request A packet control unit that discards the packet data without transmitting it by broadcast.

  As one aspect, it is possible to provide a relay device, a relay method, and a relay program that reduce the degree of occupation of the communication band.

FIG. 1 is a diagram illustrating a configuration example of an ad hoc network system. FIG. 2 is a diagram illustrating a configuration example of an ad hoc network system. FIG. 3 is a diagram illustrating a configuration example of the server apparatus. FIG. 4 is a diagram illustrating a configuration example of the gateway device. FIG. 5 is a diagram illustrating a configuration example of the relay apparatus. FIG. 6 is a flowchart showing an operation example in the relay apparatus. FIG. 7 is a flowchart showing an operation example in the relay apparatus. FIG. 8A and FIG. 8B are diagrams showing a configuration example of packet data. FIG. 9 is a diagram illustrating a configuration example of an ad hoc network system. FIG. 10 is a flowchart showing an operation example in the gateway device. FIG. 11 is a flowchart showing an operation example in the gateway device. FIG. 12A shows a server device, and FIG. 12B shows a configuration example of a gateway device. FIG. 13 is a diagram illustrating a configuration example of a relay device. FIG. 14 is a diagram illustrating a configuration example of an ad hoc network system.

  Hereinafter, modes for carrying out the present invention will be described. First, a configuration example of the processing device in the present embodiment will be described, and then an example of vector data creation processing performed in the processing device will be described.

[First Embodiment]
A first embodiment will be described. FIG. 1 is a diagram illustrating a configuration example of an ad hoc network system 10 according to the first embodiment. The ad hoc network system 10 includes a relay device 300 and a communication device 600.

  In the ad hoc network system 10 illustrated in FIG. 1, an example in which packet data addressed to the communication device 600 is relayed by the relay device 300 and transmitted to the communication device 600 is illustrated. In the ad hoc network system 10, the relay device 300 and the communication device 600 can perform wireless communication without using a base station or an access point, for example.

  The relay device 300 transmits (or relays) the received packet data to the communication device 600 that is the transmission destination of the packet data. The relay apparatus 300 includes a transmission unit 350 and a packet control unit 351.

  The transmission unit 350 receives a plurality of packet data transmitted by broadcast, and transmits the packet data to which a response request is added among the plurality of received packet data by broadcast.

  The packet control unit 351 discards the received packet data without broadcasting by determining whether or not there is a response according to the result of determining whether or not there is a response transmitted from the communication device 600 in response to the response request.

  For example, when it is determined that the response to the response request is not received from the communication device 600, the packet control unit 351 discards the packet data without transmitting the packet data received after the determination by broadcast.

  As described above, the relay device 300 discards the received packet data without broadcasting by determining whether or not there is a response according to the result of determining whether or not there is a response transmitted from the communication device 600 in response to the response request. Yes. Thereby, for example, the number of transmissions of packet data is reduced and the degree of occupation of the communication band can be reduced as compared with the case where the packet data received by the relay device 300 is transmitted by broadcast.

  On the other hand, for example, when receiving a response from the communication device 600, the packet control unit 351 transmits the packet data received after the determination by broadcast.

[Second Embodiment]
Next, a second embodiment will be described. First, a configuration example of the ad hoc network system will be described.

<Configuration example of ad hoc network system>
FIG. 2 is a diagram illustrating a configuration example of the ad hoc network system 10 according to the second embodiment.

  The ad hoc network system 10 includes a server device (hereinafter also referred to as “server”) 100, a gateway device (hereinafter also referred to as “gateway”) 200, and a plurality of relay devices 300-1 to 300-4. Prepare.

  In the ad hoc network system 10 illustrated in FIG. 2, for example, an example is illustrated in which each relay device 300-1 to 300-4 is provided in each home. In this case, each relay device 300-1 to 300-4 measures data such as the amount of electricity and gas used in each home, and the measured data is transmitted via other relay devices 300-1 to 300-4. Transmit to the gateway 200. In the example of FIG. 2, the relay device 300-4 transmits the data measured by the local station to the gateway 200 via the relay devices 300-3 and 300-1. For example, the relay device 300-3 relays data transmitted from the relay device 300-4, and further transmits data measured by the local station to the gateway 200 via the relay device 300-1.

  In the example of the ad hoc network system 10 illustrated in FIG. 2, wireless communication is performed between the gateway 200 and the relay apparatuses 300-1 and 300-2. In addition, wireless communication is performed between the relay device 300-1 and the relay device 300-3 and between the relay device 300-3 and the relay device 300-4. However, wired communication is performed between the gateway 200 and the server 100.

  In the example of the ad hoc network system 10 illustrated in FIG. 2, the number of gateways 200 connected to the server 100 represents one example, but a plurality of gateways 200 may be connected to the server 100. Details of the gateway 200 will be described later. Also, the number of relay devices 300-1 to 300-4 may be one or plural.

  The server 100 receives data transmitted from each of the relay devices 300-1 to 300-4 via the gateway 200. For example, the server 100 can display received data on a screen, calculate an electricity bill for each household based on the received data, and calculate statistical information. Further, the server 100 may generate various setting information, such as how to increase the price of the electricity bill, and instruct the gateway 200 to transmit the setting information to each relay device 300-1 to 300-4. it can. Details of the server 100 will be described later.

  The gateway 200 receives the data transmitted from each of the relay devices 300-1 to 300-4, and transmits the received data to the server 100. When the gateway 200 receives a transmission instruction such as setting information transmitted from the server 100, the gateway 200 generates a broadcast packet including the setting information and transmits the generated broadcast packet by broadcast.

  The relay devices 300-1 to 300-4 may measure data such as electricity and gas usage, and may be referred to as meters, for example. Moreover, since the relay apparatus 300-1 to 300-4 can transmit the data measured in each home to the gateway 200, it also has a function as a communication apparatus, for example. For example, the meter may be arranged in each home as a device separate from the relay devices 300-1 to 300-4. In this case, each of the relay apparatuses 300-1 to 300-4 can receive data measured by the meter from the meter and transmit the data to the gateway 200. Details of the relay devices 300-1 to 300-4 will be described later. In addition, since the structure of each relay apparatus 300-1 to 300-4 is the same, it may be called the relay apparatus 300 unless otherwise specified.

<Configuration Example of Server 100>
Next, a configuration example of the server 100 will be described. FIG. 3 is a diagram illustrating a configuration example of the server 100.

  The server 100 includes a control unit 110 and a storage unit 120. The control unit 110 includes a GW (Gateway) communication transmission unit 111, a GW communication reception unit 112, and a packet control unit 113.

  For example, when receiving the setting information and the transmission instruction from the packet control unit 113, the GW communication transmission unit 111 transmits the setting information and the like to the gateway 200 according to the transmission instruction. In this case, the GW communication transmission unit 111 generates, for example, packet data including setting information and transmits the packet data to the gateway 200.

  For example, the GW communication reception unit 112 receives packet data transmitted from the gateway 200, extracts data from the received packet data, and outputs the extracted data to the packet control unit 113.

  For example, the packet control unit 113 generates setting information and the like, outputs the generated setting information and the like to the GW communication transmission unit 111, and instructs the GW communication transmission unit 111 to transmit the information. Further, for example, when receiving data from the GW communication receiving unit 112, the packet control unit 113 can display the data on a monitor (not shown) or display various types of statistical information on the monitor.

  The storage unit 120 stores data, setting information, and the like in each process performed in the control unit 110. For example, under the control of the GW communication transmission unit 111 and the GW communication reception unit 112, data, setting information, and the like are appropriately stored in the storage unit 120, and the stored data, instructions, and the like are appropriately read out.

<Configuration Example of Gateway 200>
Next, a configuration example of the gateway 200 will be described. FIG. 4 is a diagram illustrating a configuration example of the gateway 200.

  The gateway 200 includes a control unit 210 and a storage unit 220. The control unit 210 includes a server communication reception unit 211, a server communication transmission unit 212, a wireless transmission unit 213, and a wireless reception unit 214.

  The server communication receiving unit 211 receives, for example, packet data transmitted from the server 100 and extracts setting information and the like from the received packet data. The server communication receiving unit 211 outputs the extracted setting information and the like to the packet control unit 215.

  The server communication transmission unit 212 transmits the data received from the packet control unit 215 to the server 100 in accordance with an instruction from the packet control unit 215. In this case, for example, the server communication transmission unit 212 generates packet data including data, and transmits the generated packet data to the server 100.

  The radio transmission unit 213 converts the packet data generated by the packet control unit 215 into a radio signal by performing error correction coding processing, modulation processing, frequency conversion processing, and the like according to an instruction from the packet control unit 215. . The wireless transmission unit 213 transmits the converted wireless signal to the relay device 300.

  The wireless reception unit 214 receives a wireless signal transmitted wirelessly from the relay device 300, and performs a frequency conversion process, a demodulation process, an error correction decoding process, and the like on the received wireless signal so that a packet is transmitted from the wireless signal. Extract data. The wireless reception unit 214 outputs the extracted packet data to the packet control unit 215.

  When receiving the setting information from the server communication receiving unit 211, the packet control unit 215 generates a broadcast packet including the setting information, and instructs the wireless transmission unit 213 to transmit the generated broadcast packet by broadcast.

  Note that packet data transmitted by broadcast may be referred to as a broadcast packet, for example. Details of the broadcast packet will be described later.

  In addition, when receiving packet data from the wireless reception unit 214, the packet control unit 215 extracts data from the packet data. Then, the packet control unit 215 instructs the server communication transmission unit 212 to transmit the extracted data to the server 100.

  Note that the packet control unit 215 can also generate a broadcast packet to check and maintain the network state regardless of whether or not the setting information is received from the server communication reception unit 211. The packet control unit 215 periodically transmits the broadcast packet generated in this manner to the wireless transmission unit 213, so that the broadcast packet is periodically transmitted from the gateway device 200.

  Further, for example, when receiving information other than the setting information from the server communication reception unit 211, the packet control unit 215 generates normal packet data that is not a broadcast packet, and transmits the normal packet data to the relay device 300 via the wireless transmission unit 213. It is also possible to do.

  The storage unit 220 can store data and the like as appropriate under the control of the control unit 210, and can appropriately read out the stored data.

<Configuration Example of Relay Device 300>
Next, a configuration example of the relay device 300 will be described. FIG. 5 is a diagram illustrating a configuration example of the relay device 300.

  The relay device 300 includes a control unit 310 and a storage unit 320. The control unit 310 includes a wireless reception unit 311, a wireless transmission unit 312, and a packet control unit 313.

  Note that the transmission unit 350 and the packet control unit 351 in the first embodiment correspond to, for example, the wireless transmission unit 312 and the packet control unit 313, respectively. In addition, the communication device 600 according to the first embodiment corresponds to, for example, the gateway 200 or another relay device.

  The wireless reception unit 311 receives a wireless signal transmitted from the gateway 200 or another relay device. The wireless reception unit 311 extracts packet data from the wireless signal, for example, by performing frequency conversion processing, demodulation processing, error correction decoding processing, and the like on the received wireless signal. The wireless reception unit 311 outputs the extracted packet data to the packet control unit 313.

  Further, the wireless reception unit 311 can also receive a wireless signal transmitted by broadcast transmitted from the gateway 200 or another relay device. Thereby, for example, the relay device 300 can receive a broadcast packet transmitted from the gateway 200 or another relay device. Even in this case, the wireless reception unit 311 extracts the broadcast packet from the wireless signal, and outputs the extracted broadcast packet to the packet control unit 313.

  The wireless transmission unit 312 transmits the packet data received from the packet control unit 313 to the gateway 200 or another relay device in accordance with an instruction from the packet control unit 313. In this case, for example, the wireless transmission unit 312 converts the wireless signal into a wireless signal by performing error correction coding processing, modulation processing, frequency conversion processing, and the like on the packet data, and the wireless signal is converted into the gateway 200 or another relay. Send to device.

  In addition, the wireless transmission unit 312 can transmit a wireless signal by broadcast in accordance with an instruction from the packet control unit 313, for example. Even in this case, the wireless transmission unit 312 converts the broadcast packet received from the packet control unit 313 into a wireless signal, and transmits the converted wireless signal.

  For example, when receiving packet data (or broadcast packet) from the wireless reception unit 311, the packet control unit 313 confirms a destination (or transmission destination) included in the packet data. The packet control unit 313 outputs the packet data to another processing unit in the relay apparatus 300 when the destination is the local station, and outputs the packet data to the wireless transmission unit 312 when the destination is not the local station. Thereby, for example, the relay apparatus 300 can transmit packet data other than that addressed to the own station to other relay apparatuses and the gateway 200, and packet data can be relayed.

  In addition, when the broadcast packet addressed to the own station includes setting information, the packet control unit 313 extracts the setting information from the packet and outputs the extracted setting information to the setting control unit 314. After outputting the setting information to the setting control unit 314, the packet control unit 313 terminates the received broadcast packet, for example.

  Further, when receiving data such as electricity and gas usage measured by the setting control unit 314, the packet control unit 313 generates packet data including the data. Then, the packet control unit 313 instructs the wireless transmission unit 312 to transmit the generated packet data to the gateway 200. Thereby, for example, the relay apparatus 300 can transmit the measured data to the gateway 200 or directly to the gateway 200 via another relay apparatus.

  For example, when receiving setting information from the packet control unit 313, the setting control unit 314 performs various settings according to the setting information. In addition, the setting control unit 314 measures the amount of electricity and gas used according to the setting information. The setting control unit 314 outputs the measured usage amount and the like as data to the packet control unit 313.

<Operation example>
Next, an operation example in the ad hoc network system 10 will be described. As for this operation example, there are two operation examples: an operation example in the gateway 200 and an operation example in the relay device 300. Examples of operations in the gateway 200 include a broadcast packet generation process and a transmission process of the generated broadcast packet to the relay apparatus 300. On the other hand, an operation example in the relay apparatus 300 includes, for example, broadcast packet relay processing.

  First, an operation example in the relay device 300 will be described, and then an operation example in the gateway 200 will be described.

<Operation Example in Relay Device 300>
6 and 7 are flowcharts showing an example of the relay processing operation in the relay device 300. FIG.

  When the relay apparatus 300 starts relay processing (S10), it receives a broadcast packet (S11). For example, the relay device 300 receives a broadcast packet transmitted from the gateway 200 or relayed by another relay device.

  Next, the relay apparatus 300 adds “1” to the reception counter of the broadcast packet (S12).

  For example, when receiving a broadcast packet from the wireless reception unit 311, the packet control unit 313 reads a count value from the storage unit 320, adds “1” thereto, and stores the added count value in the storage unit 320. The reception counter corresponds to the packet control unit 313 and the storage unit 320, for example.

  Next, the relay device 300 determines whether or not an ACK flag is added to the broadcast packet (S13).

  In the second embodiment, for example, the relay device 300 or the gateway 200 sets the ACK flag for a broadcast packet once every several times (for example, once every n (n is an integer of 2 or more)). The added broadcast packet can be transmitted.

  The relay device 300 and the gateway 200 can determine whether to relay the broadcast packet using the broadcast packet with the ACK flag added. Details will be described later.

  Note that a broadcast packet to which an ACK flag is added may be referred to as a broadcast packet with an ACK request, for example.

  The reception counter described above counts, for example, the timing of transmitting a broadcast packet with an ACK request. When the count value is “n”, the relay device 300 or the gateway 200 generates a broadcast packet with an ACK request, Can be sent. Details will be described later.

  Here, a configuration example of a broadcast packet with an ACK request will be described. FIG. 8A shows a configuration example of a broadcast packet with an ACK request. However, the broadcast packet with an ACK request is, for example, a kind of packet data, and the packet data including information indicating the destination is broadcast and the ACK request is a broadcast packet with an ACK request.

  As shown in FIG. 8A, the packet data 400 includes a header area 410 and a payload area 420. The header area 410 includes a type area 411, an identifier area 412, a destination area 413, a transmission source area 414, and a control flag area 415.

  The type area 411 includes information indicating the type of the packet data 400, for example. In the example of FIG. 8A, the type area 411 includes type information indicating that the packet data 400 is data.

  The identifier area 412 includes, for example, packet data identifiers. The identifier, for example, identifies other packet data. In the example of FIG. 8A, the identifier area 412 includes “0001” as the identifier.

  The destination area 413 includes destination information of the packet data 400, for example. In the example of FIG. 8A, the destination area 413 includes destination information indicating broadcast. By inserting this information, the packet data 400 becomes a broadcast packet. What is used as the destination information is, for example, address information of the transmission destination relay device 300 or gateway 200.

  The transmission source area 414 includes transmission source information of the packet data 400, for example. In the example of FIG. 8A, “A” indicating that a certain relay apparatus 300 is the transmission source is inserted in the transmission source area 414. For example, address information of the relay device 300 or the gateway 200 that is the transmission source is used as the transmission source information.

  The control flag area 415 includes information indicating whether the ACK flag is on or off, for example. When the ACK flag is on, the packet data 400 is packet data 400 with an ACK request. When the ACK flag is off, the packet data 400 is packet data 400 without an ACK flag.

  The ACK request is, for example, a response request, and the relay apparatus 300 that has received the packet data 400 with the ACK request determines whether or not to transmit an ACK signal (or an acknowledgment) based on a predetermined determination criterion. When it is determined to transmit a signal, the transmission destination is also determined. Details will be described later.

  For example, data or the like is inserted into the payload area 420.

  In the second embodiment, the packet data 400 is generated by the gateway 200, for example. Moreover, turning on the ACK flag and generating packet data with an ACK flag request may be performed by the gateway 200 or the relay device 300, for example. Details will be described later.

  Returning to FIG. 6, the relay apparatus 300 determines whether or not an ACK flag is present (S13). For example, the packet control unit 313 accesses the control flag area 415 of the broadcast packet and determines whether or not the ACK flag is on.

  When it is determined that the ACK flag is present (Yes in S13), the relay device 300 determines whether or not to transmit an ACK signal (S14).

  The relay device 300 determines whether or not to transmit the ACK signal according to the determination criterion by receiving the broadcast packet with the ACK request. There are various criteria for this discrimination. For example, the reception strength may be used, or the reception order of broadcast packets with an ACK request may be used as a reference.

  An example of the discrimination criterion based on the reception intensity will be described below. FIG. 9 shows a configuration example of the ad hoc network system 10, and an example of a discrimination criterion based on reception strength will be described using this.

  For example, the relay device (#B) 300-B receives the broadcast packet with an ACK request broadcast from the relay device (#A) 300-A (for example, S11 in FIG. 6). When receiving the broadcast packet with an ACK request, the relay device 300-B broadcasts (or relays) the received packet (S19 in FIG. 7 described later). When the other relay apparatuses (#C to #E) 300-C to 300-E receive the broadcast packet with the ACK request transmitted from the relay apparatus 300-B, the received relay packet (#C to #E) 300-C to 300-E broadcasts the received packet.

  Therefore, for example, the relay device 300-B transmits a broadcast with an ACK request having the same identifier as the broadcast packet with an ACK request transmitted (or relayed) by the own station to the other relay devices 300-A and 300-C to 300-E. May be received from.

  Then, relay apparatus 300-B measures the reception strengths of a plurality of broadcast packets with an ACK request having the same identifier, and selects the broadcast packet with an ACK request having the highest reception strength from among them. The relay device 300-B can determine the transmission source relay device that transmitted the packet as the transmission destination of the ACK signal.

  In the example of FIG. 9, the relay device 300-B receives broadcast packets with an ACK request from the plurality of relay devices 300-A and 300-C to 300-E, but is transmitted from one relay device. The packet may be received. In such a case, for example, when the reception intensity of the received packet is equal to or lower than the threshold, the relay apparatus 300-B can determine not to transmit the ACK signal, or has received the packet Thus, it can be determined that an ACK signal is transmitted to the transmission source of the packet.

  In the example of FIG. 9, the transmission source of the relay device 300-B is the relay devices 300-A and 300-C to 300-E, but may be the gateway 200, for example.

  For example, an index such as SIR (Signal to Interference Ratio) or SINR (Signal to Interference Noise Ratio) may be used as the reception intensity.

  As a determination criterion, in the case of the reception order for a broadcast packet with an ACK request, for example, it can be determined as follows.

  That is, in the example of FIG. 9, when the relay device 300-B receives a broadcast packet with an ACK request from the relay device 300-A, the relay device 300-B broadcasts the received packet. The relay apparatuses 300-A and 300-C to 300-E that have received the packet transmit (or relay) the packet by broadcast. Accordingly, the relay device 300-B can receive from the other relay devices 300-A and 300-C to 300-E a plurality of broadcast packets having the same identifier as the broadcast packet with an ACK request received from the relay device 300-A.

  For example, when a plurality of broadcast packets with an ACK request having the same identifier are received in a certain period, the relay device 300-B selects the broadcast packet with an ACK request earliest among them. Then, relay device 300-B determines to transmit an ACK signal to the transmission source (relay device 300-A in the example of FIG. 9) that has transmitted the selected broadcast packet with an ACK request.

  In this case, when only the broadcast packet with an ACK request (for example, S11 in FIG. 6) transmitted from the relay apparatus 300-A first can be received, the relay apparatus 300-B determines not to transmit the ACK signal. You can also. Alternatively, in such a case, the relay device 300-B may determine to transmit an ACK signal to the relay device 300-A.

  For example, the packet control unit 313 determines the reception strength and the reception order. For example, for the identifier of the broadcast packet with an ACK request, the packet control unit 313 measures the reception strength of a plurality of the packets with the same identifier, or stores the reception order of the plurality of the packets with the same identifier in the storage unit 320. This makes it possible to determine. For example, the reception strength may be measured by the wireless reception unit 311, and the packet control unit 313 may receive and determine the result.

  Returning to FIG. 6, when the relay apparatus 300 determines to transmit an ACK signal (Yes in S14), the relay apparatus 300 generates an ACK signal and transmits the generated ACK signal to the transmission source that transmitted the broadcast packet (S15).

  FIG. 8B shows a configuration example of the ACK signal, and shows a configuration example of the ACK signal for the broadcast packet shown in FIG.

  As shown in FIG. 8B, for example, an ACK signal is a kind of packet data 400. The type area 411 of the packet data 400 includes information indicating an ACK signal, and the identifier area 412 includes the same identifier (“0001”) as the received broadcast packet. Further, in the ACK signal, the transmission source (“A”) of the received broadcast packet is set as the destination, and the transmission source is the local station information (“B”). Such generation of the ACK signal is performed in the packet control unit 313, for example.

  Returning to FIG. 6, on the other hand, when relay device 300 determines not to transmit an ACK signal (No in S14), the process proceeds to S16 without transmitting an ACK signal.

  Further, the relay apparatus 300 proceeds to the process of S16 without performing any particular process even when the ACK flag is not added to the received broadcast packet (S13).

  The relay apparatus 300 transmits a broadcast reception counter after transmitting an ACK signal (S15), after deciding not to transmit an ACK signal (No in S14), or when an ACK flag is not added (No in S13). Is equal to the ACK request interval (S16).

  The ACK request interval is, for example, timing for transmitting a broadcast packet with an ACK request. For example, it is assumed that such an ACK request interval is held in advance in the gateway 200 and the relay device 300 so that the interval is shared. For example, when the number of broadcast packets received from the wireless reception unit 311 is “n” times, the packet control unit 313 determines that it is the same as the ACK request interval, and when it is not “n” times, It can be determined that they are not the same.

  When the broadcast reception counter is equal to the ACK request interval (Yes in S16), the relay device 300 clears the count value of the broadcast reception counter to “0” (S17). For example, the packet control unit 313 overwrites the count value stored in the storage unit 320 with “0”.

  Next, the relay device 300 turns on the ACK request for the received packet received in S11 (S18 in FIG. 7). For example, the packet control unit 313 generates a broadcast packet (for example, FIG. 8A) in which information with the ACK flag turned on is inserted.

  The relay device 300 may add an ACK flag to the broadcast packet received in S11 (Yes in S13), but even in this case, in this process (S18), the received broadcast packet with an ACK request is added. In addition, an ACK flag is added. Therefore, even when the ACK flag is not added to the received broadcast packet (S11), the relay device 300 can generate and transmit the packet when it is time to transmit the broadcast packet with an ACK request.

  Next, the relay device 300 relays the broadcast packet received in S11 (S19). That is, the relay device 300 broadcasts a broadcast packet (S18) with an ACK flag added to the broadcast packet received in S11.

  Next, the relay device 300 starts a waiting timer (S20). For example, the packet control unit 313 starts a timer and counts the timer period.

  Next, the relay device 300 determines whether or not an ACK signal has been received from another relay device within a certain period for the transmitted broadcast packet with an ACK request (S19) (S21).

  For example, in the example of FIG. 9, the relay apparatus 300-B receives ACK signals from other relay apparatuses 300-A and 300-C to 300-E within a certain period for the relayed broadcast packet with an ACK request. It is determined whether or not it has been received.

  Returning to FIG. 7, when the relay apparatus 300 receives an ACK signal from another relay apparatus (Yes in S21), the relay apparatus 300 transitions to a relayed state (S22). And the relay apparatus 300 complete | finishes a series of processes (S23).

  On the other hand, when the relay apparatus 300 does not receive an ACK signal from another relay apparatus (No in S21), the relay apparatus 300 transits to a no relay state (S24) and ends a series of processes (S23).

  For example, in the example of FIG. 9, it is assumed that the relay device 300-B receives an ACK signal from the relay device 300-E. In this case, the relay device 300-E indicates that the packet data is subsequently transmitted from the relay device 300-B due to reasons such as better reception strength (or the earliest reception order) than the relay device 300-B. You can think of it as expected.

  Therefore, in such a case, the relay apparatus 300-B can answer the expectation of packet data transmission in the relay apparatus 300-E, for example, by continuing to relay the broadcast packet received thereafter.

  On the other hand, when the relay device 300-B receives no ACK signal from any of the relay devices 300-A and 300-C to 300-E for the relayed broadcast packet with the ACK request, Therefore, it can be considered that the reception of packet data is not expected.

  Therefore, in such a case, the relay apparatus 300-B can prevent the broadcast packet received thereafter from being relayed.

  The relay apparatus 300 determines whether or not to relay a broadcast packet to be received thereafter, depending on whether the state transits to the relayed state (S22) or the state transits to the no relay state (S24).

  For example, whether or not an ACK signal has been received (S21) can be determined by the packet control unit 313 depending on whether or not an ACK signal has been received from the wireless reception unit 311. When the packet control unit 313 receives an ACK signal (Yes in S21), the packet control unit 313 transitions to a relayed state (S22), and when it does not receive an ACK signal (No in S21), transitions to a relayless state (S24). ). For example, the packet control unit 313 stores the post-transition information in the storage unit 320.

  Returning to FIG. 7, after determining the relay state transition (S22, S24) and then receiving the broadcast packet (S11 in FIG. 6), the relay device 300 performs the above-described process again.

  In this case, since the reception timing of the received broadcast packet is not the same as the ACK request interval (No in S16), for example, the broadcast packet (S11) received by the relay device 300 is a broadcast packet to which no ACK flag is added. ing.

  When receiving the broadcast packet to which the ACK flag is not added, the relay device 300 performs the following processing.

  That is, the relay device 300 determines whether or not there is a relayed state (S30 in FIG. 7). For example, the packet control unit 313 reads information on the state of the relay device 300 stored in the storage unit 320, and determines whether the relay device 300 is in a relayed state (S22) or a relayless state (S24).

  When determining that the relay is present (Yes in S30), the relay device 300 confirms that the ACK request for the received packet (S11) is off (S31). For example, the packet control unit 313 accesses the control flag area 415 of the broadcast packet received from the wireless reception unit 311 and confirms that the ACK flag is off.

  Next, the relay device 300 broadcasts (or relays) the received broadcast packet (S32).

  As described above, in the relayed state, for example, since transmission of packet data is expected from any other relay device, the relay device 300 relays the received broadcast packet.

  For example, when the packet control unit 313 confirms that the ACK flag is off, the packet control unit 313 rewrites the transmission source of the received broadcast packet with the address information of the local station, and outputs it to the wireless transmission unit 312. Thereby, for example, the received broadcast packet is transmitted by broadcast.

  And the relay apparatus 300 complete | finishes a series of processes (S23).

  On the other hand, when the relay device 300 is in the no relay state (No in S30), the relay device 300 discards the received broadcast packet without relaying (S33), and ends the series of processing (S23).

  As described above, in the state without relay, for example, any other relay device is not expected to transmit a broadcast packet, and therefore the relay device 300 does not relay the received broadcast packet.

  For example, the packet control unit 313 discards (or terminates) the broadcast packet received from the wireless reception unit 311 without outputting it to the wireless transmission unit 312.

  Thus, in the second embodiment, for example, when the relay device 300 does not receive an ACK signal from another relay device for a relayed broadcast packet with an ACK request, the relay device 300 transmits a broadcast packet received thereafter ( Discard without relaying. Thereby, for example, since the relay apparatus 300 does not transmit a broadcast packet, the amount of broadcast packets transmitted can be reduced and the degree of occupation of the communication band can be reduced compared to the case of transmitting broadcast packets.

  Note that the relay device 300 may relay a broadcast packet with an ACK request to the gateway 200, for example. Therefore, the relay apparatus 300 may receive an ACK signal from the gateway 200. Even in this case, when the ACK signal cannot be received from any other relay device including the gateway 200, the relay device 300 does not relay the broadcast packet received thereafter. Further, when the relay device 30 receives an ACK signal from any other relay device including the gateway 200, the relay device 30 relays the broadcast packet received thereafter.

<Operation example of gateway 200>
Next, an operation example in the gateway 200 will be described. 10 and 11 are flowcharts showing an operation example in the gateway 200. The gateway 200 performs, for example, broadcast packet generation processing and transmission processing, and relay processing when a broadcast packet is received.

  When the gateway 200 starts processing (S40), it generates a broadcast packet (S41). For example, the packet control unit 215 generates packet data (for example, FIG. 8A) whose transmission destination is “broadcast”.

  Next, the gateway 200 adds “1” to the broadcast transmission counter (S42). For example, the packet control unit 215 reads the counter value stored in the storage unit 220, adds “1” to the counter value, and stores the added counter value in the storage unit 220.

  Next, the gateway 200 determines whether or not the broadcast transmission counter is equal to the ACK request interval (S43).

  For example, similarly to the processing in the relay apparatus 300 (for example, S16 in FIG. 6), the gateway 200 measures the timing of transmitting a broadcast packet with an ACK request using a broadcast transmission counter. For example, the packet control unit 215 reads the counter value from the storage unit 220 and determines whether or not it is the timing (for example, n times) to transmit the broadcast packet with an ACK request.

  When the broadcast transmission counter has the same ACK request interval (Yes in S43), the gateway 200 turns on the ACK request flag of the generated broadcast packet (S44). For example, the packet control unit 215 inserts information indicating that the ACK flag is on in the control flag area 415 (for example, FIG. 8A) of the generated packet data.

  Next, the gateway 200 clears the value of the broadcast transmission counter to “0”. For example, the packet control unit 215 overwrites the broadcast counter value stored in the storage unit 220 with “0”.

  Then, the gateway 200 broadcasts a broadcast packet with an ACK request (S45).

  On the other hand, when the broadcast transmission counter is not the same as the ACK request interval (No in S43), the gateway 200 broadcasts the generated broadcast packet without turning on the ACK request (S45). For example, the packet control unit 215 inserts information indicating that the ACK flag is off in the control flag area 415 of the generated packet data, and outputs the information to the wireless transmission unit 213.

  Next, when the gateway 200 receives a broadcast packet from the relay device 300 (S50), the gateway 200 performs substantially the same processing as the relay operation in the relay device 300. Such processing is performed in the packet control unit 215, for example.

  That is, when receiving the broadcast packet (S50), the gateway 200 checks whether or not the ACK flag is added (S51). If the ACK flag is added (Yes in S51), the gateway 200 is based on the determination criterion. Then, the presence / absence of transmission of the ACK signal and the transmission destination are determined (S52 in FIG. 11). The determination criterion may be, for example, the signal strength as in the relay device 300 (S14 in FIG. 6) or the reception order of broadcast packets with an ACK request.

  When the gateway 200 determines to transmit an ACK signal (Yes in S52), the gateway 200 generates an ACK signal, and transmits the generated ACK signal to the relay apparatus 300 that has transmitted the broadcast packet with an ACK request (S53). ).

  On the other hand, when the gateway 200 determines not to transmit the ACK signal (No in S52), the gateway 200 proceeds to S54 without transmitting the ACK signal.

  After transmitting the ACK signal (S53) or determining not to transmit the ACK signal (No in S52), the gateway 200 broadcasts (or relays) the broadcast packet with the ACK request received in S50 (S54). .

  Next, the gateway 200 starts an ACK waiting timer (S55), and determines whether or not an ACK signal for the relayed broadcast packet with an ACK request (S54) has been received within a certain timer period (S56).

  When the gateway 200 receives an ACK signal within a predetermined period (Yes in S56), the gateway 200 transits to a relayed state (S57), and ends a series of processing (S58).

  On the other hand, when the gateway 200 does not receive an ACK signal within a certain period (No in S56), the gateway 200 transits to a relayless state (S59) and ends a series of processing (S58).

  After that, when receiving the broadcast packet without the ACK flag added (No in S51 in FIG. 10), the gateway 200 determines whether or not there is a relayed state (S60 in FIG. 11), and receives the received broadcast according to the state. The packet is relayed or discarded without relaying (S61, S62).

  Therefore, the gateway 200 may not receive an ACK signal for the relayed broadcast packet with an ACK request from the relay apparatus 300. In such a case, the broadcast packet received from the relay apparatus 300 is discarded without being relayed thereafter. .

  Therefore, since the gateway device 200 may not transmit the broadcast packet, the transmission amount of the broadcast packet is reduced and the degree of occupation of the communication band can be reduced as compared with the case of transmitting the broadcast packet.

[Other embodiments]
Next, other embodiments will be described.

  In the second embodiment described above, when the relay device 300 or the gateway 200 receives one ACK signal, the broadcast packet relay (for example, S32 in FIG. 7 and S61 in FIG. 11) is not broadcast. Instead, it may be transmitted by unicast.

  For example, the packet control units 313 and 215 count the number of ACK signals, and when only one is received, the destination of the received broadcast packet is the source included in the ACK signal (relay device 300 or gateway 200). And packet data having the transmission source as its own station is generated. The packet control units 313 and 215 output the generated packet data to the wireless transmission units 312 and 213, thereby transmitting the received broadcast packet as unicast packet data.

  As a result, for example, the relay device 300 or the gateway 200 has a smaller amount of transmission data than when relaying a broadcast packet, and can further reduce the degree of occupation of the communication band compared to the second embodiment. Become.

  In the second embodiment described above, the relay apparatus 300 or the gateway 200 has been described as transmitting an ACK signal to a certain relay apparatus 300 or the gateway 200 (for example, S14 in FIG. 6).

  For example, the relay device 300 or the gateway 200 may transmit an ACK signal to a plurality of transmission sources. With respect to the discrimination criterion described in the second embodiment, instead of determining any one transmission source, the relay device 300 or the gateway 200 selects an ACK signal by selecting a plurality of transmission sources from the upper level. A plurality of transmission destinations may be determined.

  Thereby, for example, when there are a plurality of paths when packet data is transmitted, a redundant path is secured, and packet data can be transmitted to a destination more reliably than in the case of one path.

  Furthermore, in the second embodiment described above, the relay apparatus 300 or the gateway 200 has been described as transitioning to a relayed state when receiving an ACK signal (for example, Yes in S21 of FIG. 7, S22).

  For example, the relay device 300 or the gateway 200 counts the number of received ACK signals within a certain period, and relays including the number of received when the broadcast packet with an ACK request is relayed next time (for example, S19 in FIG. 7). May be.

  For example, in the example of FIG. 9, when the relay device 300-B receives the ACK signal from the relay device 300-A and the relay device 300-C, the next broadcast packet with an ACK request includes the number of receptions “2”. (Or relay) (for example, S19 in FIG. 7). When relay device 300-D receives an ACK signal from relay device 300-A, it transmits the number of receptions “1” in the next broadcast packet with an ACK request.

  At this time, when receiving the broadcast packet with the ACK request including the reception number, the relay device 300-E determines whether or not to transmit the ACK signal and the transmission destination based on the reception number (for example, S14 in FIG. 6).

  For example, the relay device 300-E receives the broadcast packet with an ACK request including the reception number “2” from the relay device 300-B and the broadcast packet with an ACK request including the reception number “1” from the relay device 300-D. Consider the case of receiving.

  In this case, the relay device 300-E transmits an ACK signal to the relay device 300-B having a large number of receptions. For example, the relay device 300-E can secure a communication path by transmitting an ACK signal to the relay device 300-B that is expected to transmit more packet data.

  Alternatively, the relay device 300-E may transmit an ACK signal to the relay device 300-D with a small number of receptions. In this case, the relay apparatus 300-E can secure the communication path by distributing the communication paths as much as possible.

  How the relay apparatus 300-E determines the transmission destination of the ACK signal based on the number of receptions may be determined based on, for example, the design policy of the ad hoc network system 10. Thus, the determination of the transmission destination of the ACK signal based on the number of receptions is also one of the discrimination criteria (for example, S14 in FIG. 6) for determining the transmission destination of the ACK signal.

  Note that the number of received ACK signals is counted (for example, S21 in FIG. 7), the next number of received broadcast packets with an ACK request is included (for example, S19 in FIG. 7), and the transmission destination of the ACK signal is determined based on the number of received signals. (For example, S14 in FIG. 7) is performed in the packet control unit 313, for example.

  Furthermore, in the above-described second embodiment, the example of the radio wave intensity and the order of reception has been described as an example of the determination criterion for determining the transmission destination of the ACK signal. As a determination criterion, for example, the transmission destination of the ACK signal may be determined based on the address information of the transmission source in the broadcast packet with an ACK request. For example, the relay device 300 determines a relay device including address information with the smallest (or largest) address information of the transmission source as a transmission destination of the ACK signal (for example, S14 in FIG. 6).

  Furthermore, as a criterion for determining the transmission destination of the ACK signal, any one of the above-described examples may be appropriately selected according to the characteristics of the ad hoc network system 10, for example. For example, the relay device 300 appropriately selects one of the determination criteria from, for example, radio field strength, reception order, the number of received ACK signals, and the transmission source of a broadcast packet with an ACK request, and whether or not an ACK signal is transmitted, Alternatively, the transmission destination of the ACK signal may be determined.

  In the above-described second embodiment, the configuration examples of the server 100, the gateway 200, and the relay device 300 have been described using, for example, FIGS. Configuration examples of the server 100, the gateway 200, and the relay device 300 may be, for example, the configuration examples illustrated in FIGS. 12A to 13 respectively.

  The server 100 includes a CPU (Central Processing Unit) 130, a ROM (Read Only Memory) 131, a RAM (Random Access Memory) 132, a memory 133, an internal bus 134, and an IF (Interface) 135.

  The CPU 130 can appropriately read out the program stored in the ROM 131, load it into the RAM 132, and execute the loaded program, thereby realizing the function of the packet control unit 113 in the second embodiment, for example. Therefore, the CPU 130 corresponds to, for example, the packet control unit 113 in the second embodiment.

  The memory 133 corresponds to the storage unit 120 in the second embodiment, for example.

  Further, the IF 135 converts the data into packet data in a packet format that can be transmitted to the gateway 200 under the control of the CPU 130, for example, and transmits the packet data. Further, the IF 135 extracts data from the packet data received from the gateway 200 and outputs it to the CPU 130. Accordingly, the IF 135 corresponds to, for example, the GW communication transmission unit 111 and the GW communication reception unit 112 in the second embodiment.

  The gateway 200 includes a CPU 230, a ROM 231, a RAM 232, a memory 233, an internal bus 234, a wireless transmission unit 235, a transmission antenna 236, a reception antenna 237, a wireless reception unit 238, and an IF 239.

  The CPU 230 reads the program stored in the ROM 231, loads it into the RAM 232, and executes the loaded program, thereby realizing the function of the packet control unit 215 in the second embodiment. Therefore, the CPU 230 corresponds to, for example, the packet control unit 215 in the second embodiment.

  The memory 233 corresponds to, for example, the storage unit 220 in the second embodiment.

  Further, the wireless transmission unit 235 performs modulation processing, frequency conversion processing, and the like on the data output from the CPU 230, converts the data into a wireless signal, and outputs the wireless signal to the transmission antenna 236. The transmission antenna 236 transmits a radio signal to the relay device 300. Accordingly, the wireless transmission unit 235 and the transmission antenna 236 correspond to, for example, the wireless transmission unit 213 in the second embodiment.

  In addition, the reception antenna 237 receives the radio signal transmitted from the relay device 300 and outputs the radio signal to the radio reception unit 238. The wireless reception unit 238 performs frequency conversion processing and demodulation processing on the wireless signal, extracts data, and outputs the data to the CPU 230. Accordingly, the reception antenna 237 and the wireless reception unit 238 correspond to, for example, the wireless reception unit 214 in the second embodiment.

  Further, IF 239 extracts data from the packet data received from server 100 and outputs the data to CPU 230. The IF 239 converts data output from the CPU 230 into packet data and transmits the packet data to the server 100. Accordingly, the IF 239 corresponds to, for example, the server communication reception unit 211 and the server communication transmission unit 212 in the second embodiment.

  The relay device 300 includes a CPU 330, a ROM 331, a RAM 332, a memory 333, an internal bus 334, a wireless transmission unit 335, a transmission antenna 336, a reception antenna 337, and a wireless reception unit 338.

  The CPU 330 can implement the functions of the packet control unit 313 and the setting control unit 314 in the second embodiment, for example, by reading the program stored in the ROM 331, loading it into the RAM 332, and executing the loaded program. Therefore, the CPU 330 corresponds to, for example, the packet control unit 313 and the setting control unit 314 in the second embodiment.

  In addition, the wireless transmission unit 335 performs modulation processing and frequency conversion processing on data output from the CPU 330 to convert the data into a wireless signal, and outputs the wireless signal to the transmission antenna 336. The transmission antenna 336 transmits a radio signal to the gateway 200 and other relay devices. Therefore, the wireless transmission unit 335 and the transmission antenna 336 correspond to, for example, the wireless transmission unit 312 in the second embodiment.

  Further, the reception antenna 337 receives a radio signal transmitted from the gateway 200 or another relay device and outputs the radio signal to the radio reception unit 338. For example, the wireless reception unit 338 performs frequency conversion processing, demodulation processing, or the like on the wireless signal to extract data and outputs the data to the CPU 330. Accordingly, the reception antenna 337 and the wireless reception unit 338 correspond to the wireless reception unit 311, for example.

  The memory 333 corresponds to, for example, the storage unit 320 in the second embodiment.

  Furthermore, in any of the above-described embodiments, for example, the communication between the gateway 200 and the relay device 300 and the communication between the relay devices 300 have been described using the example of wireless communication. For example, wired communication may be performed between the gateway 200 and the relay device 300 and between the relay devices 300. For example, in such wired communication, the same operation as that of the second embodiment can be performed by performing communication by broadcast and transmission / reception of an ACK signal.

  The above is summarized as an appendix.

(Appendix 1)
A relay device that transmits received packet data to a communication device that is a transmission destination of the packet data,
A transmitter that receives a plurality of packet data transmitted by broadcast and transmits the packet data to which a response request is added among the plurality of received packet data;
A packet control unit that discards the packet data received after determining the presence / absence of the response without broadcasting, according to the result of determining the presence / absence of the response transmitted from the communication device with respect to the response request. A relay device characterized by

(Appendix 2)
The supplementary note 1, wherein the packet control unit discards the received packet data without broadcasting by determining the presence or absence of the response when there is no response to the response request from the communication device. Relay device.

(Appendix 3)
2. The relay apparatus according to claim 1, wherein when the packet control unit receives a response to the response request from the communication apparatus, the packet control unit broadcasts the received packet data after determining the presence / absence of the response.

(Appendix 4)
When the packet control unit receives the packet data to which the response request is added, the communication device of the transmission source that has transmitted the packet data to which the response request is added based on a determination criterion Decide to send to
The relay apparatus according to appendix 1, wherein the transmission unit transmits the response according to the determination.

(Appendix 5)
The relay apparatus according to appendix 1, wherein the determination criterion is a reception strength of packet data to which the response request is added, a reception order of the packet data, or a transmission source of the packet data.

(Appendix 6)
When the response is received by the packet control unit, the transmission unit includes the number of received responses received in the packet data to which the response request is added, and transmits by broadcast.
The packet control unit, when receiving packet data to which a response request including the reception number is added, determines to transmit a response to the response request based on the reception number. The relay device described.

(Appendix 7)
The relay apparatus according to claim 1, wherein the transmission unit transmits packet data to which the response request is added at a predetermined timing.

(Appendix 8)
The packet control unit generates packet data to which a response request is added among the plurality of received packet data,
The relay apparatus according to appendix 1, wherein the transmission unit transmits packet data to which the generated response request is added.

(Appendix 9)
The transmission unit according to claim 1, wherein the transmission unit receives the packet data to which the response request is transmitted and is transmitted from the communication apparatus, and transmits the received packet data to which the response request is added by broadcast. Relay device.

(Appendix 10)
When there is one response transmitted from the communication device in response to the response request, the packet control unit transmits the received packet data to the communication device that has transmitted the response after determining the presence or absence of the response. The relay device according to appendix 1, wherein

(Appendix 11)
When the packet control unit receives a plurality of packet data to which the response request is added, based on a discrimination criterion, the packet control unit transmits the packet data to which the response request is added. The relay apparatus according to appendix 4, wherein the relay apparatus determines to transmit a response to the response request to a communication apparatus.

(Appendix 12)
A relay method in a relay device that transmits received packet data to a communication device that is a transmission destination of the packet data,
The transmission unit receives a plurality of packet data transmitted by broadcast, and transmits the packet data to which a response request is added among the plurality of received packet data by broadcast,
According to the result of determining the presence / absence of a response transmitted from the communication device with respect to the response request by packet control, the received packet data is discarded without broadcasting by determining the presence / absence of the response. Relay method.

(Appendix 13)
A relay program for a computer that transmits received packet data to a communication device that is a transmission destination of the packet data,
A process of receiving a plurality of packet data transmitted by broadcast and transmitting the packet data to which a response request is added among the received plurality of packet data;
A process of discarding the packet data received after determining the presence / absence of the response without broadcasting it according to the result of determining the presence / absence of the response transmitted from the communication device to the response request is performed on the computer. Relay program.

10: Ad hoc network system 100: Server device 200: Gateway device 210: Control unit 215: Packet control unit 220: Storage unit 230: CPU
300 (300-1 to 300-4, 300-A to 300-E): relay device 310: control unit 311: wireless reception unit 312: wireless transmission unit 313: packet control unit 320: storage unit 330: CPU
400: Packet data 412: Identifier area 413: Destination area 414: Transmission source area 415: Control flag area

Claims (6)

A relay device that transmits received packet data to a communication device that is a transmission destination of the packet data,
A transmitter that receives a plurality of packet data transmitted by broadcast and transmits the packet data to which a response request is added among the plurality of received packet data;
A packet control unit that discards the packet data received after determining the presence / absence of the response without broadcasting, according to the result of determining the presence / absence of the response transmitted from the communication device with respect to the response request. A relay device characterized by   2. The packet control unit according to claim 1, wherein when there is no response to the response request from the communication device, the packet control unit discards the received packet data after determining the presence or absence of the response without transmitting by broadcast. Relay device.   2. The relay apparatus according to claim 1, wherein when the packet control unit receives a response to the response request from the communication apparatus, the packet control unit transmits the received packet data after determining the presence or absence of the response. . When the packet control unit receives the packet data to which the response request is added, the communication device of the transmission source that has transmitted the packet data to which the response request is added based on a determination criterion Decide to send to
The relay apparatus according to claim 1, wherein the transmission unit transmits the response according to the determination. A relay method in a relay device that transmits received packet data to a communication device that is a transmission destination of the packet data,
The transmission unit receives a plurality of packet data transmitted by broadcast, and transmits the packet data to which a response request is added among the plurality of received packet data by broadcast,
According to the result of determining the presence / absence of a response transmitted from the communication device with respect to the response request by packet control, the received packet data is discarded without broadcasting by determining the presence / absence of the response. Relay method. A relay program for a computer that transmits received packet data to a communication device that is a transmission destination of the packet data,
A process of receiving a plurality of packet data transmitted by broadcast and transmitting the packet data to which a response request is added among the received plurality of packet data;
A process of discarding the packet data received after determining the presence / absence of the response without broadcasting it according to the result of determining the presence / absence of the response transmitted from the communication device to the response request is performed on the computer. Relay program.

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