JP6957288B2 - Terminal equipment - Google Patents

Description

Embodiments of the present invention relate to terminal devices, relay devices, communication devices, communication systems, communication methods and programs.

In a client-server model system, a large number of axes may occur from the client to the server. In such a case, the load on the network or the server increases. In particular, when processing a large number of small-sized packets, the processing load on the network interface of the server increases. Therefore, in order to speed up communication, there is a method of converting a communication protocol from, for example, TCP (Transmission Control Protocol) to UDP (User Datagram Protocol) or the like with a network relay device.

Japanese Patent No. 4229807

However, a system that converts a communication protocol with a relay device has a problem that if an abnormality occurs in the relay device or the like, the communication protocol cannot be converted and communication between the client and the server cannot be performed. .. An object to be solved by an embodiment of the present invention is to provide a terminal device, a relay device, a communication device, a communication system, a communication method, and a program for stabilizing communication.

The terminal device of the embodiment includes a first communication unit, a second communication unit, and a control unit. The first communication unit is to one or more destinations selected from a destination group consisting of a communication device, one or more relay devices that relay transmission of a first individual packet destined for the communication device, and a destination group. The first individual packet is transmitted. The second communication unit receives a diagnostic packet indicating the operation of the relay device. The control unit selects the first relay device as the transmission destination of the first individual packet. The control unit detects the non-receipt of the diagnostic packet after the transmission of the first individual packet to the first relay device or the non-transmission of the first individual packet based on the transmission record included in the diagnostic packet. do. When the control unit detects that the first individual packet has not been transmitted, the control unit selects a device other than the first relay device included in the destination group as a transmission destination.

The block diagram which shows the outline of the communication system which concerns on 1st Embodiment and 2nd Embodiment. FIG. 3 is a block diagram showing an example of a main circuit configuration of a communication system in FIG. 1 and components included in the communication system. FIG. 2 is a block diagram showing an example of a functional configuration according to the first embodiment of the terminal device, the relay device, and the server device in FIG. The figure which shows an example of the data structure of the individual packet which concerns on 1st Embodiment to 4th Embodiment. The figure which shows an example of the data structure of the aggregate packet which concerns on 1st Embodiment to 4th Embodiment. The figure which shows an example of the data structure of the diagnostic packet which concerns on 1st Embodiment to 4th Embodiment. The flowchart which shows an example of the process which concerns on 1st Embodiment by the processor provided in the terminal apparatus in FIG. The flowchart which shows an example of the processing which concerns on 1st Embodiment to 4th Embodiment by the processor provided in the terminal apparatus in FIG. FIG. 5 is a flowchart showing an example of processing according to the first to fourth embodiments by a processor included in the relay device in FIG. FIG. 2 is a flowchart showing an example of processing according to the first embodiment by a processor included in the relay device in FIG. The flowchart which shows an example of the processing which concerns on 1st Embodiment to 4th Embodiment by the processor provided in the server apparatus in FIG. The flowchart which shows an example of the processing which concerns on 1st Embodiment to 4th Embodiment by the processor provided in the server apparatus in FIG. The flowchart which shows an example of the processing which concerns on 1st Embodiment to 4th Embodiment by the processor provided in the server apparatus in FIG. The sequence diagram which shows the information flow of the communication system which concerns on 1st Embodiment. The sequence diagram which shows the information flow of the communication system which concerns on 1st Embodiment. The sequence diagram which shows the information flow of the communication system which concerns on 1st Embodiment. FIG. 2 is a block diagram showing an example of a functional configuration according to a second embodiment of the terminal device, the relay device, and the server device in FIG. The figure which shows an example of the data structure of the diagnostic packet which concerns on 2nd Embodiment to 4th Embodiment. The flowchart which shows an example of the process which concerns on 2nd Embodiment by the processor provided in the terminal apparatus in FIG. FIG. 5 is a flowchart showing an example of processing according to the second to fourth embodiments by a processor included in the relay device in FIG. The sequence diagram which shows the information flow of the communication system which concerns on 2nd Embodiment. The block diagram which shows the outline of the communication system which concerns on 3rd Embodiment and 4th Embodiment. The flowchart which shows an example of the process which concerns on 3rd Embodiment by the processor provided in the terminal apparatus in FIG. The sequence diagram which shows the information flow of the communication system which concerns on 3rd Embodiment. The sequence diagram which shows the information flow of the communication system which concerns on 3rd Embodiment. The sequence diagram which shows the information flow of the communication system which concerns on 3rd Embodiment. The flowchart which shows an example of the process which concerns on 4th Embodiment by the processor provided in the terminal apparatus in FIG. The sequence diagram which shows the information flow of the communication system which concerns on 4th Embodiment. The sequence diagram which shows the information flow of the communication system which concerns on 4th Embodiment.

Hereinafter, communication systems according to some embodiments will be described with reference to the drawings. The same elements are designated by the same reference numerals in each drawing and its description below.
[First Embodiment]
Hereinafter, the communication system according to the first embodiment will be described.
FIG. 1 is a block diagram showing an outline of the communication system 1 according to the first embodiment. FIG. 2 is a block diagram showing an example of a main circuit configuration of a main part circuit configuration of a communication system 1 and a component included in the communication system 1 according to the first embodiment. The communication system 1 is, for example, a client-server model system composed of a terminal device 10 which is a client and a server device 30 which is a server. Communication system 1 can be applied to various systems such as station affairs system, transportation system, disaster prevention system, social infrastructure system such as water treatment system, building control system, distribution system and military system. In the following embodiment, the communication system 1 will be described by taking the case where the communication system 1 is applied to the station affairs system as an example. The communication system 1 includes a plurality of terminal devices 10, a plurality of relay devices 20, a server device 30, and a controlled device DA. Each of the plurality of terminal devices 10 is installed in, for example, one of a plurality of regions A (region A1, region A2, ..., Region An (n is a natural number)). The terminal device 10 installed in the area A1 is the terminal device 10-1-1, the terminal device 10-1-2, ..., The terminal device 10 installed in the area A2 is the terminal device 10-2-1. Terminal devices 10-2-2, ..., Terminal devices 10 installed in the area An shall be referred to as terminal devices 10-n-1, terminal devices 10-n-2, .... Further, the terminal devices 10 installed in the area A1 are collectively referred to as the terminal device 10-1, the terminal devices 10 installed in the area A2 are collectively referred to as the terminal devices 10-2, ..., The terminal devices installed in the area An. 10 is generically referred to as a terminal device 10-n. Further, the relay device 20 installed in the area A1 is the relay device 20-1, the relay device 20 installed in the area A2 is the relay device 20-2, ..., The relay device installed in the area An is the relay device 20-n. It shall be referred to as.
Further, a network NW1-1 is provided in the area A1, a network NW1-2 is provided in the area A2, ..., A network NW1-n is provided in the area An.
The terminal device 10-k and the relay device 20-k installed in the area Ak (k is a natural number of n or less) are connected to the network NW1-k. The network NW1-1 to network NW1-n are collectively referred to as network NW1.
The network NW1 is typically a communication network including a LAN (local area network). The network NW1 is typically a communication network including a private network such as an intranet. The network NW1 may be a communication network including the Internet. The network NW1 may be a communication network including a WAN (wide area network). Further, the network NW1 may be a fieldbus such as Profibus, Modbus or TC-net. Further, the network NW1 may be a wired communication line or a wireless communication line. Further, the network NW1 may be a mixture of a wired communication line and a wireless communication line.
Further, the network NW1 and the server device 30 are connected to the network NW2. The network NW2 is typically a communication network that includes the Internet. The network NW is 1, typically a communication network that includes a WAN. The network NW2 may be a communication network including a private network such as an intranet. The network NW2 may be a communication network including a LAN. Further, the network NW2 may be a communication network including a dedicated line or a public mobile phone network. Further, the network NW2 may be a wired communication line or a wireless communication line. Further, the network NW2 may be a mixture of a wired communication line and a wireless communication line.

The terminal device 10 is connected to the controlled device DA. Alternatively, the terminal device 10 is built in the controlled device DA. Alternatively, the terminal device 10 and the controlled device DA may be an integrated device. The terminal device 10 performs processing based on the data transmitted from the controlled device DA. Further, the terminal device 10 controls the control target device DA. The terminal device 10 transmits a request or the like addressed to the server device 30.
Controlled device DA is, for example, station affairs equipment, plant, manufacturing machine, equipment on disaster prevention system, equipment on transportation system, medical equipment, IoT (internet of things) equipment, PC (personal computer), tablet PC, smart. Various devices such as phones or game machines. For example, when the communication system 1 is applied to a station service system, the controlled device DA is, for example, a station service device. The station affairs equipment includes an automatic ticket gate, an automatic ticket vending machine, an automatic ticket vending machine, and the like.
The terminal device 10 includes a processor 11, a ROM (read-only memory) 12, a RAM (random-access memory) 13, an auxiliary storage device 14, a first communication I / F15, and a second communication I / F16.

The processor 11 corresponds to a central part of a computer that performs processing such as calculation and control necessary for the operation of the terminal device 10. The processor 11 controls each unit in order to realize various functions of the terminal device 10 based on a program such as system software, application software, or firmware stored in the ROM 12 or the auxiliary storage device 14. The processor 11 includes, for example, a CPU (central processing unit), an MPU (micro processing unit), a SoC (system on a chip), a DSP (digital signal processor), a GPU (graphics processing unit), an ASIC (application specific integrated circuit), and the like. PLD (programmable logic device) or FPGA (field-programmable gate array). The processor 11 is an example of a control unit. A computer centered on the processor 11 is an example of a control unit.

The ROM 12 corresponds to the main storage device of a computer centered on the processor 11. The ROM 12 is a non-volatile memory used exclusively for reading data. The ROM 12 stores the above program. Further, the ROM 12 stores data or various set values used by the processor 11 for performing various processes.

The RAM 13 corresponds to the main storage device of a computer centered on the processor 11. The RAM 13 is a memory used for reading and writing data. The RAM 13 is used as a so-called work area or the like for storing data temporarily used by the processor 11 for performing various processes.

The auxiliary storage device 14 corresponds to an auxiliary storage device of a computer centered on the processor 11. The auxiliary storage device 14 is, for example, an EEPROM (electric erasable programmable read-only memory), an HDD (hard disk drive), an SSD (solid state drive), or the like. The auxiliary storage device 14 may store the above program. Further, the auxiliary storage device 14 stores data used by the processor 11 for performing various processes, data generated by the processes of the processor 11, various setting values, and the like.

The RAM 13 or the auxiliary storage device 14 may store the transmission buffer. In the transmission buffer, for example, packets waiting to be transmitted are registered.
The RAM 13 or the auxiliary storage device 14 or the like stores the first arrival list. In the first arrival list, individual packets that have arrived at the terminal device 10 are registered.

The program stored in the ROM 12 or the auxiliary storage device 14 includes a program for executing a process described later. As an example, the terminal device 10 is transferred to the administrator of the terminal device 10 or the like with the program stored in the ROM 12 or the auxiliary storage device 14. However, the terminal device 10 may be transferred to the administrator or the like in a state where the program is not stored in the ROM 12 or the auxiliary storage device 14. Further, the terminal device 10 may be transferred to the administrator or the like in a state where a program different from the program is stored in the ROM 12 or the auxiliary storage device 14. Then, the program for executing the process described later may be separately transferred to the administrator or the like and written to the ROM 12 or the auxiliary storage device 14 under the operation of the administrator or the serviceman or the like. The transfer of the program at this time can be realized by recording on a removable storage medium such as a magnetic disk, a magneto-optical disk, an optical disk, or a semiconductor memory, or by downloading via a network NW.

The first communication I / F 15 is an interface for the terminal device 10 to communicate with the controlled device DA. The terminal device 10 is connected to the controlled device DA by, for example, the first communication I / F15. The first communication I / F 15 receives the detection signal D1 transmitted from the controlled device DA. Further, the first communication I / F15 transmits a control signal D2 to the controlled device DA.

The second communication I / F 16 is an interface for the terminal device 10 to communicate via the network NW1 or the like. The terminal device 10 is connected to the network NW1 by, for example, the second communication I / F16. The second communication I / F 16 is an example of the first communication unit. The second communication I / F 16 is an example of the second communication unit. The second communication I / F 16 is an example of the first terminal communication unit. The second communication I / F 16 is an example of the second terminal communication unit.

The relay device 20 has a function of relaying communication between the terminal device 10 and the server device 30. Further, the relay device 20 has a function of converting a protocol in communication between the terminal device 10 and the server device 30. The relay device 20 is, for example, a gateway or the like. The relay device 20 includes a processor 21, a ROM 22, a RAM 23, an auxiliary storage device 24, and a communication I / F 25.

The processor 21 corresponds to a central part of a computer that performs processing such as calculation and control necessary for the operation of the relay device 20. The processor 21 controls each unit in order to realize various functions of the relay device 20 based on a program such as system software, application software, or firmware stored in the ROM 22 or the auxiliary storage device 24. The processor 21 is, for example, a CPU, MPU, SoC, DSP, GPU, ASIC, PLD, FPGA, or the like. Alternatively, the processor 21 is a combination of these. The processor 21 is an example of a processing unit. A computer centered on the processor 21 is an example of a processing unit.

The ROM 22 corresponds to the main storage device of a computer centered on the processor 21. The ROM 22 is a non-volatile memory used exclusively for reading data. The ROM 22 stores the above program. The ROM 22 also stores data or various set values used by the processor 21 to perform various processes.

The RAM 23 corresponds to the main storage device of a computer centered on the processor 21. The RAM 23 is a memory used for reading and writing data. The RAM 23 is used as a so-called work area or the like for storing data temporarily used by the processor 21 for performing various processes.

The auxiliary storage device 24 corresponds to an auxiliary storage device of a computer centered on the processor 21. The auxiliary storage device 24 is, for example, an EEPROM, an HDD, an SSD, or the like. The auxiliary storage device 24 may store the above program. Further, the auxiliary storage device 24 stores data used by the processor 21 for performing various processes, data generated by the processes of the processor 21, various setting values, and the like.

The RAM 23, the auxiliary storage device 24, or the like stores the first aggregation buffer. In the first aggregation buffer, individual packets waiting to be aggregated are registered.

The program stored in the ROM 22 or the auxiliary storage device 24 includes a program for executing a process described later. As an example, the relay device 20 is transferred to the administrator of the relay device 20 or the like with the program stored in the ROM 22 or the auxiliary storage device 24. However, the relay device 20 may be transferred to the administrator or the like in a state where the program is not stored in the ROM 22 or the auxiliary storage device 24. Further, the relay device 20 may be transferred to the administrator or the like in a state where a program different from the program is stored in the ROM 22 or the auxiliary storage device 24. Then, the program for executing the process described later may be separately transferred to the administrator or the like and written to the ROM 22 or the auxiliary storage device 24 under the operation of the administrator or the service person. The transfer of the program at this time can be realized by recording on a removable storage medium such as a magnetic disk, a magneto-optical disk, an optical disk, or a semiconductor memory, or by downloading via a network NW.

The communication I / F 25 is an interface for the relay device 20 to communicate via the network NW1 or the like. The relay device 20 is connected to the network NW1 by, for example, the communication I / F25. The communication I / F 25 is an example of the first communication unit. The communication I / F 25 is an example of the second communication unit. The communication I / F 25 is an example of a third communication unit. The communication I / F 25 is an example of the first relay communication unit. The communication I / F 25 is an example of a second relay communication unit. The communication I / F 25 is an example of a third relay communication unit.

The server device 30 performs processing based on the content of the request transmitted by the terminal device 10, for example. Then, the server device 30 transmits a response addressed to the source of the request, for example, based on the content of the request. The server device 30 includes a processor 31, a ROM 32, a RAM 33, an auxiliary storage device 34, and a communication I / F 35. The server device 30 is an example of a communication device.

The processor 31 corresponds to a central part of a computer that performs processing such as calculation and control necessary for the operation of the server device 30. The processor 31 controls each unit to realize various functions of the server device 30 based on a program such as system software, application software, or firmware stored in the ROM 32 or the auxiliary storage device 34 or the like. The processor 31 is, for example, a CPU, MPU, SoC, DSP, GPU, ASIC, PLD, FPGA, or the like. Alternatively, the processor 31 is a combination of these. The processor 31 is an example of a generation unit. A computer centered on the processor 31 is an example of a generator.

The ROM 32 corresponds to the main storage device of a computer centered on the processor 31. The ROM 32 is a non-volatile memory used exclusively for reading data. The ROM 32 stores the above program. The ROM 32 also stores data or various set values used by the processor 31 to perform various processes.

The RAM 33 corresponds to the main storage device of a computer centered on the processor 31. The RAM 33 is a memory used for reading and writing data. The RAM 33 is used as a so-called work area or the like for storing data temporarily used by the processor 31 for performing various processes.

The auxiliary storage device 34 corresponds to an auxiliary storage device of a computer centered on the processor 31. The auxiliary storage device 34 is, for example, EEPROM, HDD, SSD, or the like. The auxiliary storage device 34 may store the above program. In addition, the auxiliary storage device 34 stores data used by the processor 31 to perform various processes, data generated by the processes of the processor 31, various set values, and the like.

The RAM 33, the auxiliary storage device 34, and the like store a second aggregation buffer. In the second aggregation buffer, individual packets waiting to be aggregated are registered.
The RAM 33, the auxiliary storage device 34, and the like store a second arrival list. In the second arrival list, individual packets that have arrived at the server device 30 are registered.

The program stored in the ROM 32 or the auxiliary storage device 34 includes a program for executing a process described later. As an example, the server device 30 is transferred to the administrator of the server device 30 or the like with the program stored in the ROM 32 or the auxiliary storage device 34. However, the server device 30 may be transferred to the administrator or the like in a state where the program is not stored in the ROM 32 or the auxiliary storage device 34. Further, the server device 30 may be transferred to the administrator or the like in a state where a program different from the program is stored in the ROM 32 or the auxiliary storage device 34. Then, the program for executing the process described later may be separately transferred to the administrator or the like and written to the ROM 32 or the auxiliary storage device 34 under the operation of the administrator or the serviceman or the like. The transfer of the program at this time can be realized by recording on a removable storage medium such as a magnetic disk, a magneto-optical disk, an optical disk, or a semiconductor memory, or by downloading via a network.

The communication I / F 35 is an interface for the server device 30 to communicate via the network NW2 or the like. The server device 30 is connected to the network NW2 by, for example, the communication I / F35.

The terminal device 10, the relay device 20, and the server device 30 will be further described with reference to FIG. FIG. 3 is a block diagram showing the functional configurations of the terminal device 10, the relay device 20, and the server device 30.

The terminal device 10 includes an input unit 101, an ID addition unit 102, a transmission destination selection unit 103, a transmission unit 104, a first reception unit 105, a diagnosis unit 106, a second reception unit 107, an ID confirmation unit 108, a reception selection unit 109, and the like. The output unit 110 is included.

The input unit 101 receives the detection signal D1 from the control target device DA. For example, the first communication I / F functions as the input unit 101.

The ID addition unit 102 adds a detection ID (identifier) for uniquely identifying the detection signal D1 to the detection signal. The ID addition unit 102 is, for example, a combination of a terminal ID uniquely assigned to each terminal device 10 and a value (sequence number) that is incremented each time a detection signal is generated in each controlled device DA. Is the detection ID. Here, the detection signal D1 to which header information such as the packet type, ID, and data size is added is referred to as an individual packet D3. For example, the processor 11 functions as an ID addition unit 102.

The destination selection unit 103 selects whether to transmit the individual packet D3 to the relay device 20 or to the server device 30 depending on the operating status of the relay device 20. For example, the processor 11 functions as a destination selection unit 103.

The transmission unit 104 transmits the individual packet D3 to the relay device 20 or the server device 30. For example, the second communication I / F 16 functions as a transmission unit 104.

The first receiving unit 105 receives the diagnostic packet D5 transmitted from the relay device 20. For example, the second communication I / F 16 functions as the first receiving unit 105.

The diagnosis unit 106 confirms whether the diagnosis packet D5 is received within a certain time after transmitting the individual packet D3, and if the diagnosis packet D5 can be received, diagnoses that the relay device 20 is normal, and determines that the relay device 20 is normal. If it cannot be received, it is diagnosed that the relay device 20 is abnormal. Further, the diagnosis unit 106 may confirm whether the diagnosis packet can be received at a fixed cycle and diagnose the abnormality of the relay device 20. Further, the diagnostic unit 106 assumes that if the diagnostic packet D5 cannot be received within a certain period of time after transmitting the individual packet D3, it will take time for the relay device 20 to recover, and the destination of the individual packet D3 is fixed. It may be fixed to the server device 30 for hours. For example, the processor 11 functions as a diagnostic unit 106.

The second receiving unit 107 receives the individual packet D3 transmitted from the relay device 20 or the server device 30. The individual packet D3 received by the second receiving unit 107 stores, for example, an ID for identifying the packet, a control signal D2, and the like. For example, the second communication I / F 16 functions as the second receiving unit 107.

The ID confirmation unit 108 confirms whether or not the individual packet D3 has arrived by referring to the terminal ID and the sequence number of the received individual packet D3. For example, the processor 11 functions as an ID confirmation unit 108.

The reception selection unit 109 refers to the terminal ID and the sequence number of the individual packet D3 to determine whether the individual packet D3 has already arrived. Then, if the reception selection unit 109 determines that the individual packet D3 has arrived, the reception selection unit 109 discards the individual packet. For example, the processor 11 functions as a reception selection unit 109.

The output unit 110 reads the control signal D2 from the individual packet D3 and outputs the control signal D2. The output destination is, for example, the controlled device DA or the like. For example, the first communication I / F functions as an output unit 110.

The relay device 20 includes a first reception unit 201, an aggregation unit 202, an aggregation packet generation unit 203, a first transmission unit 204, a diagnostic packet generation unit 205, a second transmission unit 206, a second reception unit 207, a separation unit 208, and a first unit. (3) The transmission unit 209 is included.

The first receiving unit 201 receives the individual packet D3 transmitted by the terminal device 10. For example, the communication I / F 25 functions as the first receiving unit 201.

The aggregation unit 202 concatenates and holds individual packets at a fixed time interval, a fixed number of packets, or a fixed packet size. The aggregation unit 202 can determine how many individual packets are to be concatenated based on the bandwidth of the network NW2, the MTU (maximum transmission unit) size, the transmission frequency from the terminal device 10, and the like. For example, when the MTU is 1500 bytes, the aggregation unit 202 may set the aggregation packet to 1500 bytes or less. For example, the processor 21 and the RAM 23 function as the aggregation unit 202.

The aggregated packet generation unit 203 generates an aggregated packet D4 in which header information such as a packet type, a relay device ID, and a sequence number is added to one or more concatenated individual packets. For example, the processor 21 functions as an aggregate packet generation unit 203.

The first transmission unit 204 transmits the aggregated packet D4 to the server device 30. For example, the communication I / F 25 functions as the first transmission unit 204.

The diagnostic packet generation unit 205 removes the data part of the detection signal from the concatenated individual packets, and generates the diagnostic packet D5 to which header information such as the packet type, the ID of the relay device, and the sequence number is added. If the individual packets to be concatenated do not exist in the aggregation unit 202, the diagnostic packet D5 containing only the packet type, the ID of the relay device, and the sequence number is transmitted. The interval for transmitting the diagnostic packet D5 is, for example, a period of about several milliseconds. When the aggregated packet generation unit 203 aggregates individual packets at regular time intervals, the time interval at which the diagnostic packet generation unit 205 transmits the diagnostic packet D5 is set to the time interval at which the aggregate packet generation unit 203 aggregates the individual packets. It may be the same. For example, the processor 21 functions as a diagnostic packet generator 205.

The second transmission unit 206 simultaneously transmits the diagnostic packet D5 to the plurality of terminal devices 10. For example, the communication I / F 25 functions as the second transmission unit 206.

The second receiving unit 207 receives the aggregated packet D4 transmitted from the server device 30. For example, the communication I / F 25 functions as the second receiving unit 207.

The separation unit 208 separates the aggregated packet D4 transmitted from the server device 30 into individual packets D3. For example, the processor 21 functions as a separator 208.

The third transmission unit 209 transmits the separated individual packet D3 to each terminal device 10. For example, the communication I / F 25 functions as the third transmission unit 209.

The server device 30 includes a reception unit 301, a separation unit 302, a reception selection unit 303, a determination unit 304, an ID addition unit 305, a destination selection unit 306, a first transmission unit 307, an aggregation unit 308, an aggregation packet generation unit 309, and a first unit. (Ii) The transmission unit 310 is included.

The receiving unit 301 receives the individual packet D3 transmitted from the terminal device 10 and the aggregated packet D4 transmitted from the relay device 20. For example, the communication I / F 35 functions as the receiving unit 301.

The separation unit 302 determines whether the received packet is an individual packet D3 or an aggregate packet D4, and if it is an aggregate packet D4, separates it into individual packets. Further, the separation unit 302 outputs the destination information for changing the destination to be returned depending on whether the received packet is an aggregate packet or an individual packet. For example, the processor 31 functions as a separator 302.

The reception selection unit 303 reads the ID of the individual packet, and discards the individual packet that has already been received. For example, the processor 31 functions as a reception selection unit 303.

The determination unit 304 processes the application based on the detection signal D1 included in the data portion of the received individual packet D3, and generates the control signal D2. For example, in the case of station affairs equipment, fare calculation or IC (integrated circuit) card access information issuance. For example, the processor 31 functions as a determination unit 304.

The ID addition unit 305 adds an ID for uniquely identifying the control signal D2 generated by the determination unit 304 to the control signal. For example, the ID is a pair of the ID of the destination terminal device 10 and the sequence number that is incremented each time a control signal is generated. A control signal to which header information such as a packet type, ID, and data size is added is also referred to as an individual packet D3. For example, the processor 31 functions as the ID addition unit 305.

The destination selection unit 306 selects whether to transmit the individual packet D3 to the terminal device 10 or the relay device 20 based on the destination information determined by the separation unit 302. When the destination selection unit 306 receives the individual packet D3 from the terminal device 10, the first transmission unit 307 transmits the individual packet D3 to the terminal device 10. When the destination selection unit 306 receives the aggregated packet D4 from the relay device 20, the destination selection unit 306 stores the individual packet D3 in the aggregate unit 308. For example, the processor 31 functions as a destination selection unit 306.

The first transmission unit 307 transmits the individual packet D3 to the terminal device 10. For example, the communication I / F 35 functions as the first transmission unit 307.

The aggregation unit 308 concatenates and holds individual packets at a fixed time interval, a fixed number of packets, or a fixed packet size. For example, the processor 31 and the RAM 33 function as the aggregation unit 308.

The aggregated packet generation unit 309 generates an aggregated packet D4 in which header information such as a packet type, a destination relay device ID, and a sequence number is added to the concatenated individual packets. For example, the processor 31 functions as an aggregate packet generator 309.

The second transmission unit 310 transmits the aggregated packet D4 to the relay device 20. For example, the communication I / F 35 functions as the second transmitter 310.

The individual packet D3 has, for example, a data structure as shown in FIG. FIG. 4 is a diagram showing an example of the data structure of the individual packet D3. The individual packet D3 includes a packet type (D31), a terminal ID (D32), a sequence number (D33), a data size (D34), and data (D35).
The packet type (D31) includes a value for determining whether the packet including the packet type (D31) is an individual packet or an aggregate packet. The packet type (D31) is, for example, a predetermined value, a port number for communication, or the like.
The terminal ID (D32) includes the terminal ID of the source or destination terminal device 10. For example, the terminal ID (D32) includes, for example, a value obtained by combining the IP address and the port number of the terminal device. Alternatively, for example, the terminal ID (D32) uses a unique session ID issued by the server device 30 to the terminal device 10 each time the terminal device 10 accesses the server device 30.
The sequence number (D33) includes a number that increases each time the terminal device 10 or the server device 30 that is the source of the individual packet D3 transmits the individual packet. For example, the ID addition unit 102 may increase the number by one, or may increase the number by the size of the individual packet D3.
The data size (D34) includes a value indicating the data capacity of the data (D35).
The data (D35) stores a detection signal D1 input to the terminal device 10, a control signal D2 generated by the server device 30, and the like.
The individual packet D3 is transmitted by, for example, TCP. Alternatively, the individual packet D3 may be transmitted by UDP.

The aggregated packet D4 has, for example, a data structure as shown in FIG. FIG. 5 is a diagram showing an example of the data structure of the aggregated packet D4. The aggregated packet D4 includes a packet type (D31), a relay ID (D41), a sequence number (D42), and one or more individual packet data (for example, individual packet data 1 (D43), individual packet data 2 (D43), ….)including.
The packet type (D31) is the same as that of the individual packet D3.
The relay ID (D41) includes an ID that uniquely identifies the transmission source or transmission destination relay device 20. For example, a value obtained by combining the IP address and the port number of the relay device 20, or a unique session ID issued by the communication device each time the relay device 20 connects to the server device 30 is used.
The sequence number (D42) includes a number that is incremented each time each of the relay device 20 and the server device 30 transmits an aggregated packet. For example, the number is incremented by 1 each time an aggregate packet is transmitted. Alternatively, the number may be increased by the size of the aggregated packet each time the aggregated packet is transmitted.
Each individual packet data (D43) is the individual packet D3 excluding the packet type D31.
The aggregated packet D4 is transmitted by, for example, UDP.

The diagnostic packet D5 has, for example, a data structure as shown in FIG. FIG. 6 is a diagram showing an example of the data structure of the diagnostic packet D5. The diagnostic packet D5 includes a packet type (D31), a relay ID (D41), a sequence number (D42), and zero or more individual packet headers (for example, individual packet header 1 (D51), individual packet header 2 (D51), etc. ….)including.
The packet type (D31), relay ID (D41), and sequence number (D42) are the same as those of the aggregated packet D4.
Each individual packet header (D51) is generated based on the individual packet D3. That is, the individual packet header (D51) is obtained by extracting the terminal ID (D32) and the sequence number (D33) from the individual packet D3. The individual packet header (D51) is an example of transmission recording.
The diagnostic packet D5 is transmitted by, for example, UDP.

Hereinafter, the operation of the communication system 1 according to the first embodiment will be described with reference to FIGS. 7 to 13. The content of the process in the following operation description is an example, and various processes capable of obtaining the same result can be appropriately used. Each of FIGS. 7 and 8 is a flowchart of processing by the processor 11 of the terminal device 10. The processor 11 executes these processes based on a program stored in the ROM 12 or the auxiliary storage device 14. The processor 11 simultaneously processes the processes shown in FIGS. 7 and 8 in parallel or in parallel. 9 and 10 are flowcharts of processing by the processor 21 of the relay device 20. The processor 21 executes these processes based on a program stored in the ROM 22 or the auxiliary storage device 24 or the like. The processor 21 simultaneously processes the processes shown in FIGS. 9 and 10 in parallel or in parallel. Each of FIGS. 11 to 13 is a flowchart of processing by the processor 31 of the server device 30. The processor 31 executes these processes based on a program stored in the ROM 32, the auxiliary storage device 34, or the like. The processor 31 simultaneously processes the processes shown in FIGS. 11 to 13 in parallel or in parallel. When the processor 11 starts the process shown in FIG. 13, the variable i is assigned to the RAM 13 and the like.
Unless otherwise specified, the processor 11, the processor 21, and the processor 31 proceed to step S (m + 1) after the processing of step S (m) (m is a natural number).

The terminal device 10 generates data destined for the server device 30 in response to the input of the detection signal D1 from the controlled device DA. The data is transmitted in the form of individual packets. The individual packet is registered in, for example, a transmission buffer for waiting for transmission.

In step S111 of FIG. 7, the processor 11 of the terminal device 10 determines whether or not to generate an individual packet destined for the server device 30. That is, the processor 11 confirms whether or not the detection signal D1 is input from the controlled device DA, for example. If the processor 11 does not generate an individual packet, the processor 11 determines No in step S111 and repeats step S111. On the other hand, if the processor 11 generates an individual packet, the processor 11 determines Yes in step S111 and proceeds to step S112.

In step S112, the processor 11 generates an individual packet destined for the server device 30. For example, the individual packet includes the detection signal D1 input in step S71. The individual packet generated in step S112 is an example of the first individual packet.

In step S113, the processor 11 instructs the second communication I / F 16 to transmit the individual packet generated in step S112 to the relay device 20. In response to this instruction, the second communication I / F 16 transmits the individual packet to the relay device 20. The transmitted individual packet is received by the communication I / F 25 of the relay device 20. At this time, for example, the processor 11 cancels the registration of the individual packet in the processing buffer.

On the other hand, in step S211 of FIG. 9, the processor 21 of the relay device 20 waits for the packet to be received by the communication I / F 25. If the packet is received, the processor 21 determines Yes in step S211 and proceeds to step S212.

In step S212, the processor 21 determines whether or not the packet received in step S211 is an individual packet. If the packet received in step S211 is an individual packet, the processor 21 determines Yes in step S212 and proceeds to step S213.

In step S213, the processor 21 registers the individual packet received in step S211 in the first aggregation buffer. The processor 21 returns to step S211 after step S213.

Further, in step S221 of FIG. 10, the processor 21 resets the timer. The timer is a timer for measuring the time since the second diagnostic packet was transmitted last time. The second diagnostic packet will be described later.

In step S222, the processor 21 determines whether or not the aggregation condition is satisfied. The aggregation condition includes at least one or more of the following conditions (1) to (3), for example.
(1) A certain period of time or more has passed since the relay device 20 last aggregated the individual packets.
(2) The number of individual packets registered in the first aggregation buffer has exceeded a certain number.
(3) The total data capacity of the individual packets registered in the first aggregation buffer has exceeded a certain level.
If, for example, the processor 21 determines that any of the conditions shown in the above (1) to (3) included in the aggregation condition is satisfied, it is determined in step S222 that the aggregation condition is satisfied. If the processor 21 determines that the aggregation condition is not satisfied, it determines No in step S222 and proceeds to step S223.

In step S223, the processor 21 determines whether or not the time T1 or more has elapsed since the timer was reset. The time T1 is set in advance by, for example, the administrator of the relay device 20. Alternatively, the time T1 may be predetermined by the designer of the relay device 20 or the like. If the time T1 or more has not elapsed since the timer was reset, the processor 21 determines No in step S223 and returns to step S222. Thus, the processor 21 repeats steps S222 and S223 until the aggregation condition is satisfied or the time T1 or more elapses after resetting the timer.

If the processor 21 determines that the aggregation condition is satisfied while in the standby state of step S222 and step S223, it determines Yes in step S222 and proceeds to step S224.
In step S224, the processor 21 generates an aggregated packet that aggregates a plurality of individual packets registered in the first aggregation buffer. At this time, for example, the processor 21 targets the individual packets registered in the first aggregation buffer in order from the oldest individual packet. Then, the processor 21 combines and aggregates the individual packets to be aggregated. The processor 21 cancels the registration of the individual packets to be aggregated in the first aggregation buffer. Further, it is preferable that the processor 21 generates an aggregated packet so that the size of the aggregated packet does not exceed the MTU (maximum transmission unit). For example, when the processor 21 determines that the size of the aggregated packet exceeds the MTU when the number of aggregation targets is increased further, the processor 21 does not further aggregate individual packets. The aggregated packet generated in step S224 is an example of the first aggregated packet.
However, when the number of individual packets registered in the first aggregation buffer is one, the processor 21 generates an aggregation packet including only one individual packet. Further, the processor 21 generates an aggregated packet including only one individual packet even when the size of the aggregated packet exceeds the MTU just by aggregating the two individual packets.

In step S225, the processor 21 instructs the communication I / F 25 to transmit the aggregated packet aggregated packet generated in step S224 to the server device 30. In response to this instruction, the communication I / F 25 transmits the aggregated packet to the server device 30. The transmitted aggregated packet is received by the communication I / F 35 of the server device 30.

In step S226, the processor 21 generates a first diagnostic packet. The first diagnostic packet is, for example, the diagnostic packet D5 as shown in FIG.
In step S227, the processor 21 instructs the communication I / F 25 to transmit the first diagnostic packet generated in step S226 to the terminal device 10. In response to this instruction, the communication I / F 25 transmits the first diagnostic packet to the terminal device 10. The transmitted first diagnostic packet is received by the second communication I / F 16 of the terminal device 10. The destination of the first diagnostic packet is the terminal device 10 which is the source of each of the individual packets targeted for aggregation in step S224. The processor 21 returns to step S222 after the processing of step S227.

On the other hand, in step S114 of FIG. 7, the processor 11 of the terminal device 10 determines whether or not the first diagnostic packet has been received by the first communication I / F15. If the first diagnostic packet is not received, the processor 11 determines No in step S114 and proceeds to step S115.

In step S115, the processor 11 determines whether or not a timeout has occurred. That is, the processor 11 confirms whether or not the time T2 or more has elapsed after the process of step S113. The time T2 is set in advance by, for example, the administrator of the terminal device 10. Alternatively, the time T2 may be predetermined by the designer of the terminal device 10 or the like. If the processor 11 has not timed out, the processor 11 determines No in step S115 and returns to step S114. Thus, the processor 11 repeats steps S114 and S115 until the first diagnostic packet is received by the first communication I / F15 or timed out.

If the first diagnostic packet is received by the first communication I / F15 while in the standby state of step S114 and step S115, the processor 11 determines Yes in step S114 and returns to step S111. ..

On the other hand, in step S311 of FIG. 11, the processor 31 of the server device 30 waits for the packet to be received by the communication I / F 25. If the packet is received, the processor 31 determines Yes in step S311 and proceeds to step S312.

In step S312, the processor 31 determines whether or not the packet received in step S311 is an aggregate packet. If the packet received in step S311 is an aggregate packet, the processor 31 determines Yes in step S312 and proceeds to step S313.

In step S313, the processor 31 divides the individual packets included in the aggregated packets received in step S311 into individual individual packets.

In step S314, the processor 31 discards the individual packets that have already arrived among the individual packets included in the aggregated packets received in step S311. The processor 31 determines whether or not it has arrived by referring to, for example, the second arrival list.

In step S315, the processor 31 registers the individual packets divided in step S313, excluding the individual packets discarded in step S314, in the processing buffer.

In step S316, the processor 31 registers the individual packet registered in the processing buffer in step S315 in the second arrival list. The processor 31 returns to step S311 after the processing of step S316.

Further, in step S331 of FIG. 12, the processor 31 determines whether or not individual packets are registered in the processing buffer. If the individual packet is not registered in the processing buffer, the processor 31 determines No in step S331 and repeats step S331. On the other hand, if the individual packet is registered in the processing buffer, the processor 31 determines Yes in step S331 and proceeds to step S332.

In step S332, the processor 31 determines one individual packet as a processing target from the ones registered in the processing buffer. Then, the processor 31 performs processing based on the content of the individual packet to be processed. At this time, the processor 31 determines, for example, the individual packet having the oldest date and time registered in the processing buffer as the processing target. Further, the processor 31 cancels the registration of the individual packet determined as the processing target in the processing buffer.

In step S333, the processor 31 determines whether or not it is necessary to return a response to the terminal device 10 which is the source of the individual packet determined as the processing target in step S332 as a result of the processing in step S332. If it is not necessary for the processor 31 to return a response to the terminal device 10, the processor 31 determines No in step S333 and proceeds to step S334. On the other hand, if the processor 31 needs to return a response to the terminal device 10, it determines Yes in step S333 and proceeds to step S334.

In step S334, the processor 31 determines whether or not the individual packet determined as the processing target in step S332 has arrived at the server device 30 via the relay device 20. If the individual packet arrives at the server device 30 via the relay device 20, the processor 31 determines Yes in step S334 and proceeds to step S335.

In step S335, the processor 31 generates a response destined for the terminal device 10 which is the source of the individual packet determined as the processing target in step S332. The response includes, for example, the control signal D2. The processor 31 generates the response as an individual packet arriving at the terminal device 10 via the relay device 20. The relay device 20 is a relay device 20 via which individual packets determined to be processed in step S332 have passed.

In step S336, the processor 31 registers the individual packet, which is the response generated in step S334, in the second aggregation buffer. The processor 31 returns to step S331 after the processing of step S336.

Further, in step S341 of FIG. 13, the processor 31 sets the value of the variable i to 1.

In step S342, the processor 31 determines whether or not the individual packet transmitted via the relay device 20-i among the individual packets registered in the second aggregation buffer satisfies the aggregation condition. The aggregation condition of the individual packet transmitted via the relay device 20-i includes at least one or more of the following conditions (4) to (6), for example.
(4) A certain time or more has passed since the server device 30 last aggregated the individual packets transmitted via the relay device 20-i.
(5) The number of individual packets registered in the second aggregation buffer and transmitted via the relay device 20-i has exceeded a certain number.
(6) The total data capacity of the individual packets transmitted via the relay device 20-i registered in the second aggregation buffer has exceeded a certain level.
If, for example, the processor 31 determines that any of the conditions (4) to (6) included in the aggregation condition is satisfied, it is determined in step S341 that the aggregation condition is satisfied. If the individual packets transmitted via the relay device 20-i do not satisfy the aggregation condition, the processor 31 determines No in step S342 and proceeds to step S343.

In step S343, the processor 31 increments the variable i and increments the value of the variable i by 1.

In step S344, the processor 31 determines whether or not the value of the variable i exceeds n. If the value of the variable i does not exceed n, the processor 31 determines No in step S344 and returns to step S342. On the other hand, if the value of the variable i exceeds n, the processor 31 determines Yes in step S344 and returns to step S341.
Thus, the processor 31 repeats the processes of steps S342 to S344 to check whether the individual packets transmitted to each of the relay devices 20-1 to 20-n satisfy the aggregation condition. Then, the processor 31 repeats the processes of steps S341 to S344 until any of the individual packets transmitted to the relay devices 20-1 to the relay device 20-n satisfy the aggregation condition.

If the individual packets transmitted via the relay device 20-i satisfy the aggregation condition, the processor 31 determines Yes in step S342 and proceeds to step S345.
In step S345, the processor 31 aggregates the individual packets transmitted via the relay device 20-i among the individual packets registered in the second aggregation buffer to generate the aggregated packets. At this time, for example, among the individual packets transmitted via the relay device 20-i, the processor 31 extracts from the second aggregation buffer in order from the individual packet having the oldest date and time registered in the second aggregation buffer. And aggregate. The processor 31 cancels the registration of the individual packet taken out from the second aggregation buffer in the second aggregation buffer. Further, it is preferable that the processor 31 generates the aggregated packet so that the size of the aggregated packet does not exceed the MTU. For example, when the processor 31 determines that the size of the aggregated packet exceeds the MTU when the next individual packet is aggregated, the processor 31 completes the generation of the aggregated packet without performing further aggregation.
However, when the number of individual packets transmitted via the relay device 20-i registered in the second aggregation buffer is one, the processor 31 generates an aggregation packet including only one individual packet. Further, the processor 31 generates an aggregated packet including only one individual packet even when the size of the aggregated packet exceeds the MTU just by aggregating the two individual packets.
The aggregated packet generated in step S345 is an example of a second aggregated packet.

In step S346, the processor 31 instructs the communication I / F 35 to transmit the aggregated packet generated in step S345 to the relay device 20-i. In response to this instruction, the communication I / F 35 transmits the aggregated packet to the relay device 20-i. The transmitted aggregated packet is received by the communication I / F 25 of the relay device 20-i. The processor 31 proceeds to step S343 after the processing of step S346.

On the other hand, if the packet received in step S211 is an aggregated packet, the processor 21 of the relay device 20 determines No in step S212 and proceeds to step S214.
In step S214, the processor 21 divides the individual packets included in the aggregated packets received in step S211 into individual individual packets.

In step S215, the processor 21 instructs the communication I / F 25 to transmit each individual packet divided in step S214 to the terminal device 10 which is the destination of each individual packet. In response to this instruction, the communication I / F 25 transmits each of the individual packets to the terminal device 10 which is the destination of each individual packet. The transmitted individual packet is received by the second communication I / F 16 of the terminal device 10 which is the destination of each individual packet.

On the other hand, in step S121 of FIG. 7, the processor 11 of the terminal device 10 waits for the individual packet to be received by the second communication I / F 16. If the individual packet is received, the processor 11 determines Yes in step S121 and proceeds to step S122.

In step S122, the processor 11 waits for the individual packet received in step S121 to arrive. The processor 11 determines whether or not it has arrived by referring to, for example, the first arrival list. If the individual packet received in step S121 has arrived, the processor 11 determines Yes in step S122 and returns to step S121. On the other hand, if the individual packet received in step S121 has not arrived, the processor 11 determines No in step S122 and proceeds to step S123.

In step S123, the processor 11 registers the individual packet received in step S121 in the first arrival list.

In step S124, the processor 11 performs processing based on the content of the individual packet received in step S121. For example, if the individual packet contains a control signal D2, the processor 11 instructs the first communication I / F 15 to input the control signal D2 to the controlled device DA. In response to this instruction, the first communication I / F 15 inputs the control signal D2 to the controlled device DA connected to the first communication I / F 15. The processor 11 returns to step S121 after the processing of step S124.
The controlled device DA to which the control signal D2 is input operates based on the control signal D2.

If the processor 11 times out in the standby state of step S114 and step S115 of FIG. 7, it determines Yes in step S115 and proceeds to step S117. The timeout occurs, for example, when the relay device 20 has an abnormality and the first diagnostic packet is not transmitted to the terminal device 10. Alternatively, the timeout occurs, for example, when there is an abnormality in the route between the terminal device 10 and the relay device 20, and communication between the terminal device 10 and the relay device 20 cannot be performed normally.
In step S116, the processor 11 sends the individual packet generated in step S112 to the second communication I / F 16 so as to arrive at the server device 30 without passing through the relay device 20 and transmit the individual packet to the server device 30. Instruct against. In response to this instruction, the second communication I / F 16 transmits the individual packet to the server device 30. The transmitted individual packet is received by the communication I / F 35 of the server device 30.

On the other hand, if the packet received in step S311 of FIG. 11 is an individual packet, the processor 31 of the server device 30 determines No in step S312 and proceeds to step S317.

In step S317, the processor 31 determines whether or not the individual packet received in step S311 has arrived. The processor 31 determines whether or not it has arrived by referring to, for example, the second arrival list. If the individual packet received in step S311 has arrived, the processor 31 determines Yes in step S317 and proceeds to step S318.

In step S318, the processor 31 discards the individual packet received in step S311. The processor 31 returns to step S311 after the processing of step S318.

On the other hand, if the individual packet received in step S311 has not arrived, the processor 31 determines No in step S317 and proceeds to step S319.

In step S319, the processor 31 registers the individual packet received in step S311 in the processing buffer.

In step S320, the processor 31 registers the individual packet received in step S311 in the second arrival list. The processor 31 returns to step S311 after the processing of step S320.

Further, if the individual packet taken out from the processing buffer in step S332 has not arrived at the server device 30 via the relay device 20, the processor 31 determines No in step S334 and proceeds to step S337. ..

In step S337, the processor 31 generates a response destined for the terminal device 10 that is the source of the individual packets taken out of the processing buffer in step S332. The response includes, for example, the control signal D2. The processor 31 generates the response as an individual packet arriving at the terminal device 10 without going through the relay device 20. The individual packet generated in step S337 is an example of the second individual packet.

In step S338, the processor 31 sends the individual packet generated in step S337 to the communication I / F 35 so as to arrive at the destination terminal device 10 without going through the relay device 20. Instruct against. In response to this instruction, the communication I / F 35 transmits the individual packet to the terminal device 10. The transmitted individual packet is received by the second communication I / F 16 of the terminal device 10. The processor 31 returns to step S331 after the process of step S338.

On the other hand, in step S117 of FIG. 7, the processor 11 of the terminal device 10 determines whether or not the second diagnostic packet has been received by the second communication I / F 16. If the second diagnostic packet has not been received by the second communication I / F 16, the processor 11 determines No in step S117 and proceeds to step S118. The second diagnostic packet will be described later.

In step S118, the processor 11 determines whether or not to generate individual packets in the same manner as in step S111. Similar to step S111, if the processor 11 does not generate an individual packet, the processor 11 determines No in step S118 and returns to step S117. Thus, the processor 11 repeats steps S117 and S118 until it determines that the second diagnostic packet is received by the second communication I / F 16 or generates an individual packet.

If the processor 11 determines to generate an individual packet while in the standby state of step S117 and step S118, it determines Yes in step S118 and proceeds to step S119.
The processor 11 generates individual packets in the same manner as in step S112. The individual packet generated in step S119 is an example of the first individual packet.

In step S120, the processor 11 causes the individual packet destined for the server device 30 to arrive at the server device 30 without going through the relay device 20 and transmits the second communication I / to the server device 30. Instruct F16. In response to this instruction, the second communication I / F 16 transmits the individual packet to the server device 30. The transmitted individual packet is received by the communication I / F 35 of the server device 30.

On the other hand, if the processor 21 of the relay device 20 is in the standby state of step S222 and step S223 of FIG. 10 and the time T1 or more has elapsed after resetting the timer, it determines Yes in step S223 and steps. Proceed to S227.
In step S227, the processor 21 determines whether or not the relay device 20 is operating normally. If the processor 21 determines that the relay device 20 is not operating normally, the processor 21 determines No in step S227 and returns to step S222. On the other hand, if the processor 21 determines that the relay device 20 is operating normally, it determines Yes in step S227 and proceeds to step S228.

In step S228, the processor 21 generates a second diagnostic packet. The second diagnostic packet is a diagnostic packet that does not include individual packet data. Further, the second diagnostic packet is generated so as to be distinguishable from the first diagnostic packet. The processor 21 that generated the second diagnostic packet instructs the communication I / F 25 to transmit the second diagnostic packet to all the terminal devices 10 in the same area as the area where the relay device 20 is installed. .. That is, the processor 21 of the relay device 20-k instructs the communication I / F 25 to transmit the second diagnostic packet to each of the terminal devices 10-k connected to the network NW1-k. In response to this instruction, the communication I / F 25 transmits the second diagnostic packet to the respective terminal devices 10-k. The transmitted second diagnostic packet is received by the second communication I / F 16 of each terminal device 10-k. The processor 21 returns to step S221 after the processing of step S228.
The second diagnostic packet is data that notifies the terminal device 10 that the relay device 20 that is the source of the second diagnostic packet is operating normally. The second diagnostic packet is, for example, data that is periodically transmitted from the relay device 20 to the terminal device 10 every time T1.

On the other hand, if the second diagnostic packet is received by the second communication I / F 16 while in the standby state of step S117 and step S118 of FIG. 7, the processor 11 of the terminal device 10 says Yes in step S117. The determination is made and the process returns to step S111.

From the above, the computer centered on the processor 11 functions as a control unit by performing the processes shown in FIGS. 7 and 8. The computer centered on the processor 21 functions as a processing unit by performing the processes shown in FIGS. 9 and 10. The computer centered on the processor 31 functions as a generator by performing the processes shown in FIGS. 11 to 13.

The operation of the communication system 1 according to the first embodiment will be further described with reference to FIGS. 14 to 16. Each of FIGS. 14 to 16 is a sequence diagram showing an example of the information flow of the communication system 1. Note that FIGS. 14 to 16 do not cover the flow of information in the communication system 1, and there may be a flow of information (not shown). In the description of the sequence diagram, the region Ak will be taken as an example.

FIG. 14 shows an example of a communication sequence when there is no abnormality in the relay device 20.
The terminal ID of the terminal device 10-k-1 is "1", and the terminal ID of the terminal device 10-k-2 is "2". The terminal device 10-k-1 transmits an individual packet D3 including the detection signal D1 of “α” input by the input process to the relay device 20. Further, the terminal device 10-k-2 transmits an individual packet D3 including the detection signal D1 of "β" input by the input process to the relay device 20. The individual packet D3 transmitted by the terminal device 10-k-1 includes the terminal ID 1 (ID: 1) and the sequence number 1 (Seq: 1). The individual packet D3 transmitted by the terminal device 10-k-2 includes the terminal ID 2 (ID: 2) and the sequence number 1 (Seq: 1).
The relay device 20 that has received the individual packet D3 buffers the individual packet in the aggregation buffer by the aggregation process. Then, the relay device 20 aggregates the buffered individual packets and generates an aggregated packet D4 and a diagnostic packet D5 to which the ID of the relay device 20 and the sequence number of the aggregated packet are added. The relay device 20 transmits the aggregated packet D4 to the server device 30, and transmits the diagnostic packet D5 to the terminal device 10-k-1 and the terminal device 10-k-2. The terminal device 10-k-1 and the terminal device 10-k-2 receive the diagnostic packet D5. Since the terminal device 10-k-1 and the terminal device 10-k-2 that have received the diagnosis packet D5 have received the diagnosis packet D5, it is determined that there is no abnormality in the relay device 20.
After receiving the aggregated packet D4, the server device 30 separates the aggregated packet D4 into individual individual packets included in the aggregated packet D4 by a separation process. Then, the server device 30 reads the terminal ID and the sequence number of the individual packet, confirms that the individual packet has not been received, and performs the determination process. The control signals D2 "X" and "Y" are generated by the determination process, and the aggregate packet D6 is generated by the aggregation process. The data structure of the aggregated packet D6 is, for example, the same as the data structure of the aggregated packet D4. Since the aggregated packet D4 in which the detection signal D1 is stored is transmitted from the relay device 20, the aggregated packet D6 in which the control signal D2 is stored is transmitted to the relay device 20. After receiving the aggregated packet D6, the relay device 20 separates a plurality of individual packets D7 included in the aggregated packet D6 from the aggregated packet D6 by a separation process. Then, the relay device 20 transmits the individual packet D7 to each of the terminal device 10-k-1 and the terminal device 10-k-2. The data structure of the individual packet D7 is the same as that of the individual packet D3, for example.
The terminal device 10-k-1 and the terminal device 10-k-2 read the terminal ID and sequence number of the individual packet D7 in which the control signal D2 is stored, confirm that the individual packet is an unreceived individual packet, and confirm that the individual packet is an unreceived individual packet. The output process of D2 is performed.
By transmitting the diagnostic packet D5 to the terminal device 10, the relay device 20 can confirm that the relay device 20 is operating normally, and the relay device 20 aggregates the packets to load the server device 30. Can be reduced.

FIG. 15 shows an example of a communication sequence when an abnormality occurs in the relay device 20.
It is assumed that the relay device 20 is in a state in which the individual packet D3 cannot be received, or is in a state in which processing cannot be performed even if the individual packet D3 is received. In this case, the relay device 20 cannot transmit the diagnostic packet D5 to the terminal device 10-k-1 and the terminal device 10-k-2. Therefore, the terminal device 10-k-1 and the terminal device 10-k-2 confirm that the diagnostic packet cannot be received within a certain time after the individual packet D3 is transmitted. Based on the confirmation, the terminal device 10-k-1 and the terminal device 10-k-2 determine that the relay device 20 is abnormal. Then, each of the terminal device 10-k-1 and the terminal device 10-k-2 transmits the individual packet D3 to the server device 30.
When the server device 30 receives the individual packet D3 transmitted from each of the terminal device 10-k-1 and the terminal device 10-k-2, the server device 30 reads the terminal ID and the sequence number of the individual packet. Then, the server device 30 confirms that the received individual packet D3 is an unreceived individual packet. The server device 30 that has confirmed that it has not been received performs a determination process. The server device 30 generates the control signals D2 "X" and "Y" by the determination process, respectively. Since the individual packet D3 in which the detection signal D1 is stored is transmitted from the terminal device 10, the server device 30 does not perform the aggregation process. Then, the server device 30 transmits the individual packet D7 in which the control signal D2 is stored to the terminal device 10-k-1 and the terminal device 10-k-2.
The terminal device 10-k-1 and the terminal device 10-k-2 read the terminal ID and the sequence number from the individual packet D7 in which the control signal D2 is stored, and confirm that the individual packet is an unreceived individual packet. The terminal device 10-k-1 and the terminal device 10-k-2, which have been confirmed to have not been received, perform output processing of the control signal D2.
Since the terminal device 10 can select the transmission destination of the individual packet according to the state of the relay device 20, even if an abnormality occurs in the relay device 20, the control can be continued with a constant delay time. can. When the timing for generating the diagnostic packet is set to a cycle of about several milliseconds, the communication delay time when an abnormality occurs in the relay device 20 becomes several milliseconds, and the real-time control property can be ensured.

FIG. 16 shows an example of a communication sequence when an abnormality occurs in the diagnostic packet generation unit 205 or the second transmission unit 206 of the relay device 20.
It is assumed that the relay device 20 is in a state in which the diagnostic packet D5 cannot be transmitted or is in a state in which the transmission of the diagnostic packet D5 is delayed. Further, it is assumed that the relay device 20 can transmit the aggregated packet D4 to the server device 30. In this case, the terminal device 10-k-1 and the terminal device 10-k-2 cannot receive the diagnostic packet D5 transmitted from the relay device 20 before the time-out occurs.
The terminal device 10-k-1 and the terminal device 10-k-2 confirm that the diagnostic packet D5 cannot be received within a certain period of time after transmitting the individual packet D3, and determine that the relay device 20 is abnormal. , The individual packet D3 is transmitted to the server device 30.
From the above, the server device 30 receives the aggregated packet D4 transmitted from the relay device 20 and the individual packet D3 transmitted from each of the terminal device 10-k-1 and the terminal device 10-k-2. When the server device 30 receives the aggregated packet D4, the server device 30 performs a separation process on the aggregated packet D4. Then, the server device 30 reads the terminal ID and the sequence number of the individual packets included in the aggregated packet D4. Further, when the server device 30 receives the individual packet D3, the server device 30 reads the terminal ID and the sequence number of the individual packet D3. The server device 30 performs determination processing on the individual packet included in the aggregated packet D4 and the individual packet arriving earlier in the individual packet D3, and the server device 30 performs the same individual packet arriving after that. Discard.
By adding the ID and the sequence number to the individual packets, the server device 30 does not process the detection signal D1 in duplicate. Further, the terminal device 10 and the server device 30 can continue normal control even when some functions of the relay device 20 become abnormal.

According to the communication system 1 of the first embodiment, the relay device 20 aggregates a plurality of individual packets transmitted from the terminal device 10 and transmits them to the server device 30. Therefore, the communication system 1 can reduce the communication load of the server device 30. Further, the server device 30 aggregates the responses to each terminal device 10 and transmits them to the relay device 20. As a result, the communication load of the server device 30 is reduced.

Further, according to the communication system 1 of the first embodiment, when the relay device 20 normally transmits the aggregated packet that aggregates the individual packets received from the terminal device 10 to the server device 30, the relay device 20 sends the diagnostic packet to the terminal device 10. By transmitting, it is possible to notify the terminal device 10 that the transmission has been performed normally. The terminal device 10 can know from the diagnostic packet that the transmission has been performed normally. Further, the terminal device 10 can determine that the relay device 20 has an abnormality when the diagnostic packet is not sent. Then, when the relay device 20 determines that the relay device 20 has an abnormality, the relay device 20 directly transmits the individual packet to the server device 30 without going through the relay device 20. Therefore, even if there is an abnormality in the relay device 20, individual packets are transmitted to the server device 30 without being lost. Further, from the above, the communication system 1 can communicate between the terminal device 10 and the server device 30 even when the relay device 20 has an abnormality. That is, stable communication is possible between the terminal device 10 and the server device 30.

The second diagnostic packet is periodically transmitted even while the terminal device 10 is not transmitting the individual packet data. Therefore, the terminal device 10 can know that the relay device 20 has recovered from the abnormal state by receiving the second diagnostic packet.

When the controlled device DA is a station equipment, the amount of data of the detection signal D1 and the control signal D2 is small, so that the effect of reducing the load by packet aggregation is large. Therefore, the communication system 1 of the embodiment is particularly useful when the controlled device DA is a station equipment. Further, when the control target device DA is an automatic ticket gate, real-time performance is required for the time from the output of the detection signal D1 to the input of the control signal D2. Therefore, when the controlled device DA includes an automatic ticket gate, the communication system 1 of the embodiment is particularly useful.

[Second Embodiment]
Hereinafter, the communication system according to the second embodiment will be described.
Since the configuration of the communication system 1 according to the second embodiment is the same as that of FIGS. 1 and 2 of the first embodiment, the description thereof will be omitted. However, the communication system 1 according to the second embodiment shows a functional configuration as shown in FIG. 17 instead of FIG. FIG. 17 is a block diagram showing the functional configurations of the terminal device 10, the relay device 20, and the server device 30.

The terminal device 10 includes an input unit 101, an ID addition unit 102, a transmission destination selection unit 103, a transmission unit 104, a first reception unit 105, a diagnosis unit 106, a second reception unit 107, an ID confirmation unit 108, a reception selection unit 109, and the like. In addition to the output unit 110, the abnormality notification unit 121 is included.

The abnormality notification unit 121 has a function of transmitting an abnormality signal D8 to the outside and temporarily stopping the input unit 101. The abnormality signal D8 of the terminal device 10 is notified to the user who uses the terminal device 10 or the controlled device DA. For example, the lamp or screen display of the automatic ticket gate notifies the user that an abnormality has occurred in the communication system 1. Further, the abnormality notification unit 121 temporarily stops the input unit 101. As a result, the abnormality notification unit 121 can reduce the load on the server device 30.

The relay device 20 includes a first reception unit 201, an aggregation unit 202, an aggregation packet generation unit 203, a first transmission unit 204, a diagnostic packet generation unit 205, a second transmission unit 206, a second reception unit 207, a separation unit 208, and a first unit. (Iii) In addition to the transmission unit 209, the load measurement unit 221 is included.

The load measuring unit 221 has a function of measuring the height of the load of the relay device 20. The additions measured by the load measuring unit 221 are, for example, the usage rate of the processor 21 of the relay device 20, the usage rate of the RAM 23, the usage rate of the network, and the like. The load measurement unit 221 measures the height of the load at the timing when the relay device 20 generates the aggregated packet, and notifies the diagnosis packet generation unit of the load information. When the load height of the relay device 20 exceeds a certain value, the diagnostic packet generation unit 205 transmits the diagnostic packet D5 to the terminal device 10 without storing a part of the individual packet header D51.

Since the functional configuration of the server device 30 is the same as that of FIG. 3 of the first embodiment, the description thereof will be omitted.

The aggregated packet D4 generated by the diagnostic packet generation unit 205 of the second embodiment has, for example, a data structure as shown in FIG.
The diagnostic packet generation unit 205 reduces the number of individual packet headers D51 included in the diagnostic packet D5 according to the height of the load measured by the load measurement unit. For example, when the load is equal to or greater than the first threshold value, the diagnostic packet generation unit 205 determines that the load of the relay device 20 is higher than the reference value, and reduces the number of individual packet headers D51 included in the diagnostic packet D5. Further, the diagnostic packet generation unit 205 reduces the individual packet header D51 more as the load increases, for example. Then, the diagnostic packet generation unit 205 does not include the individual packet header in the diagnostic packet D5, for example, when the load height is equal to or higher than the second threshold value.
Similarly, the aggregation unit 202 reduces the number of individual packet data D43 to be concatenated according to the height of the load measured by the load measurement unit. For example, when the load is equal to or greater than the first threshold value, the aggregation unit 202 determines that the load of the relay device 20 is higher than the reference value, and reduces the number of individual packet data D43 to be concatenated. Further, for example, the aggregation unit 202 reduces the number of individual packet data D43 to be connected as the load increases. Then, for example, when the height of the load is equal to or higher than the second threshold value, the aggregation unit 202 does not concatenate the individual packet data D43. Therefore, the aggregated packet generation unit 203 is also inferior to generating the aggregated packet D4.
The number of individual packet headers D51 included in the diagnostic packet D5 generated by the diagnostic packet generation unit 205 and the number of individual packet data D43 concatenated by the aggregation unit 202 are the same. Further, the individual packet header D51 included in the diagnostic packet D5 generated by the diagnostic packet generation unit 205 and the individual packet data D43 concatenated by the aggregation unit 202 correspond to the same individual packet.
The diagnostic packet D5 shown in FIG. 18 is generated when four individual packets are to be aggregated, as an example.
For example, when the load is less than 40%, the diagnostic packet generation unit 205 generates a diagnostic packet D5 including all four individual packet headers D51. At this time, the number of individual packet data D43 concatenated by the aggregation unit 202 is also four. For example, when the load is 40% or more and less than 50%, the diagnostic packet generation unit 205 reduces the individual packet header D51 by one to generate a diagnostic packet D5 including only three individual packet headers D51. At this time, the number of individual packet data D43 concatenated by the aggregation unit 202 is also three. For example, when the load is 50% or more and less than 60%, the diagnostic packet generation unit 205 reduces the individual packet header D51 by half, that is, by two, and generates a diagnostic packet D5 including only two individual packet headers D51. At this time, the number of individual packet data D43 concatenated by the aggregation unit 202 is also two. For example, when the load is 60% or more and less than 70%, the diagnostic packet generation unit 205 reduces the individual packet header D51 by three to generate a diagnostic packet D5 including only one individual packet header D51. At this time, the number of individual packet data D43 concatenated by the aggregation unit 202 is also one. For example, when the load is 70% or more, the diagnostic packet generation unit 205 reduces all four individual packet headers D51 to generate a diagnostic packet D5 that does not include the individual packet header D51. At this time, the number of individual packet data D43 concatenated by the aggregation unit 202 is also 0. In the above example, the first threshold is 40%. Further, in the case of the above example, the second threshold value is 70%.
The diagnostic packet D5 shown in FIG. 18 is an example, and does not limit the threshold values such as the first threshold value and the second threshold value. Further, the diagnostic packet D5 shown in FIG. 18 is an example, and does not limit the number in which the diagnostic packet generation unit 205 reduces the individual packet header D51. Further, the threshold value does not have to be a fixed value.

Hereinafter, the operation of the communication system 1 according to the second embodiment will be described with reference to FIGS. 8, 9, 11, 11, 13, 19, and 20. The content of the process in the following operation description is an example, and various processes capable of obtaining the same result can be appropriately used. In the second embodiment, the terminal device 10 performs the processes shown in FIGS. 19 and 8 instead of the processes shown in FIGS. 7 and 8 of the first embodiment. FIG. 19 is a flowchart of processing by the processor 11 of the terminal device 10. The processor 11 executes this process based on a program stored in the ROM 12 or the auxiliary storage device 14. The processor 11 simultaneously processes the processes shown in FIGS. 19 and 8 in parallel or in parallel. Further, in the second embodiment, the relay device 20 performs the processes shown in FIGS. 9 and 20 instead of the processes shown in FIGS. 9 and 10 of the first embodiment. FIG. 20 is a flowchart of processing by the processor 21 of the relay device 20. The processor 21 executes this process based on a program stored in the ROM 22 or the auxiliary storage device 24 or the like. The processor 21 simultaneously processes the processes shown in FIGS. 9 and 20 in parallel or in parallel. Further, the server device 30 performs the processes shown in FIGS. 11 to 13 in the same manner as in the first embodiment.

In the second embodiment, if the processor 11 of the terminal device 10 determines Yes in step S114 of FIG. 19, the process proceeds to step S131.
In step S131, the processor 11 determines whether or not the individual packet transmitted in step S113 is normally transmitted from the relay device 20 to the server device 30. The processor 11 makes the determination by referring to the first diagnostic packet received in step S114. That is, if the first diagnostic packet includes the individual packet header generated from the individual packet transmitted in step S113, the processor 11 determines that the packet has been normally transmitted. Then, if the first diagnostic packet does not include the individual packet header generated from the individual packet transmitted in step S113, the processor 11 considers that the individual packet has not been transmitted. If the processor 11 determines that the individual packet transmitted in step S113 has been normally transmitted from the relay device 20, it determines Yes in step S131 and returns to step S111. On the other hand, if the processor 11 determines that the individual packet transmitted in step S113 is not normally transmitted from the relay device 20, it determines No in step S131 and proceeds to step S116.

Further, in the second embodiment, if the processor 21 of the relay device 20 determines Yes in step S222 of FIG. 20, the process proceeds to step S231.
In step S231, the processor 21 of the relay device 20 acquires load information indicating the height of the load of the relay device 20.

In step S232, the processor 21 generates aggregate packets in the same manner as in step S224. However, in step S232, when the load on the relay device 20 is high, the processor 21 does not aggregate all the individual packets to be aggregated, but reduces the number of individual packets included in the aggregated packets. Further, the processor 21 reduces the number of individual packets included in the aggregated packet as the load on the relay device 20 increases. The processor 21 cancels the registration of the individual packets to be aggregated, including those not included in the aggregated packets, in the first aggregation buffer.
In step S233, the processor 21 instructs the communication I / F 25 to transmit the aggregated packet generated in step S232 to the server device 30. In response to this instruction, the communication I / F 25 transmits the aggregated packet to the server device 30. The transmitted aggregated packet is received by the communication I / F 35 of the server device 30.

In step S234, the processor 21 generates a first diagnostic packet. The processor 21 reduces the number of individual packet headers included in the first diagnostic packet as the load on the relay device 20 increases. Further, the individual packet header included in the first diagnostic packet corresponds to the individual packet data included in the aggregated packet generated in step S232.

In step S235, the processor 21 instructs the communication I / F 25 to transmit the first diagnostic packet generated in step S234 to the terminal device 10. In response to this instruction, the communication I / F 25 transmits the first diagnostic packet to the terminal device 10. The transmitted first diagnostic packet is received by the second communication I / F 16 of the terminal device 10. The destination of the first diagnostic packet is the terminal device 10 which is the source of each of the individual packets targeted for aggregation in step S224. The processor 21 returns to step S222 after the processing of step S235.

The operation of the communication system 1 according to the second embodiment will be further described with reference to FIG. FIG. 21 is a sequence diagram showing an example of the information flow of the communication system 1. Note that FIG. 21 does not cover the flow of information in the communication system 1, and there may be a flow of information (not shown).

FIG. 21 shows an example of a communication sequence when the load of the relay device 20 is high. It is assumed that when the relay device 20 receives individual packets from the terminal device 10-k-1 and the terminal device 10-k-2, the load of the relay device is 50%. Since the load on the relay device 20 is high, the diagnostic packet D5 and the aggregate packet D4 are included without including the individual packet header D51 and the individual packet data D43 corresponding to the ID and sequence number of the terminal device 10-k-2. Suppose to generate. The diagnostic packet D5 and the aggregated packet D4 include an individual packet header D51 having an ID and a sequence number of the terminal device 10-k-1 and an individual packet data D43. The relay device 20 transmits the generated diagnostic packet D5 and the aggregated packet D4. Since the terminal device 10-k-1 has an individual packet header having a terminal ID of 1 in the diagnostic packet D5, it can be determined that the individual packet D3 is transmitted via the relay device 20. On the other hand, the terminal device 10-k-2 determines that the individual packet D3 has not been transmitted from the relay device 20 because the diagnostic packet D5 does not have an individual packet header with a terminal ID of 2, and directly transmits the individual packet D3 to the server device 30. Send to.
The server device 30 transmits the control signal D2 for the detection signal D1 received as an aggregate packet to the relay device 20 as an aggregate packet. Then, the server device 30 transmits the control signal D2 for the detection signal D1 received as an individual packet to the terminal device 10-k-2 as an individual packet.

The communication system 1 of the second embodiment has the same effect as that of the first embodiment.
Further, according to the communication system 1 of the second embodiment, the relay device 20 does not aggregate a part of the received individual packets when the load is high. This makes it possible to prevent the load on the relay device 20 from becoming too high.
Further, the relay device 20 transmits a diagnostic packet indicating that the individual packet has not been transmitted to the server device 30 to the terminal device 10 which is the source of the individual packet that has not been aggregated. As a result, the terminal device 10 can know that the individual packet was not transmitted to the server device 30. Then, in this case, the terminal device 10 directly transmits the individual packet to the server device 30 without going through the relay device 20.
From the above, the communication system 1 can prevent the load on the relay device 20 from becoming too high to allow communication between the terminal device 10 and the server device 30.

[Third Embodiment]
Hereinafter, the communication system according to the third embodiment will be described.
The configuration of the communication system 1b according to the third embodiment will be described with reference to FIG. Unlike the first embodiment and the second embodiment, the communication system 1b is provided with a plurality of relay devices 20 in each area A. Then, each relay device is connected to the network NW1 of each region A. FIG. 22 shows a case where two relay devices 20 are installed in each area A. However, depending on the area A, there may be a case where only one relay device 20 is installed. In addition, a plurality of relay devices 20-k installed in the area Ak shall be referred to as relay device 20-k-1, relay device 20-k-2, ....
The circuit configuration of the main part of each device included in the communication system 1b is the same as that of the communication system 1 shown in FIG. 2 of the first embodiment and the second embodiment, and thus the description thereof will be omitted. Further, the functional configuration of each device included in the communication system 1b is the same as that of the communication system 1 shown in FIG. 17 of the second embodiment, and thus the description thereof will be omitted.

Hereinafter, the operation of the communication system 1b according to the third embodiment will be described with reference to FIGS. 8, 9, 11, 11, 13, 20, and 23. The content of the process in the following operation description is an example, and various processes capable of obtaining the same result can be appropriately used. In the third embodiment, the terminal device 10 performs the processes shown in FIGS. 23 and 8 instead of the processes shown in FIGS. 19 and 8 of the second embodiment. FIG. 23 is a flowchart of processing by the processor 11 of the terminal device 10. The processor 11 executes this process based on a program stored in the ROM 12 or the auxiliary storage device 14. When the processor 11 starts the process shown in FIG. 23, the variable j is assigned to the RAM 13 and the like. The processor 11 simultaneously processes the processes shown in FIGS. 23 and 8 in parallel or in parallel. The relay device 20 performs the processes shown in FIGS. 9 and 20 as in the second embodiment. Further, the server device 30 performs the processes shown in FIGS. 11 to 13 in the same manner as in the first embodiment and the second embodiment. In the following description, the case of region Ak will be described as an example.

In the third embodiment, the processor 11 proceeds to step S141 after the processing of step S112 of FIG. 23.
In step S141, the processor 11 sets the value of the variable j to 1. As a result, the destination of the individual packet becomes the relay device 20-k-1.

In step S142, the processor 11 instructs the first communication I / F 15 to transmit individual packets to the relay device 20-k-j. In response to this instruction, the first communication I / F 15 transmits the individual packet to the relay device 20-k-j. The transmitted individual packet is received by the communication I / F 25 of the relay device 20-k-j.

In the third embodiment, if the processor 11 determines Yes in the process of step S115, the processor 11 proceeds to step S143. Still, in the third embodiment, if the processor 11 determines No in step S131, the processor 11 proceeds to step S143.
In step S143, the processor 11 increments the variable j and increments the value of the variable j by 1. As a result, the destination of the individual packet is changed from the relay device 20-k-j to the relay device 20-k- (j + 1).

In step S144, the processor 11 determines whether or not there is a relay device 20 to be transmitted next. That is, the processor 11 confirms whether or not the relay device 20-k-j exists. If there is a relay device 20 to be transmitted next, the processor 11 determines Yes in step S144 and returns to step S142. In step S142 when the process proceeds from step S144 to step S142, the processor 11 performs a process so as to transmit the same individual packet as the individual packet transmitted in the previous step S142.

Further, if there is no relay device 20 to be transmitted next, the processor 11 determines No in step S144 and proceeds to step S145.
In step S145, the processor 11 makes the same individual packet as the individual packet transmitted in step S142 arrive at the server device 30 without passing through the relay device 20, and transmits the second communication to the server device 30. Instruct I / F16. In response to this instruction, the second communication I / F 16 transmits the individual packet to the server device 30. The transmitted individual packet is received by the communication I / F 35 of the server device 30. The processor 11 proceeds to step S117 after the process of step S145.

In the third embodiment, the processor 31 of the server device 30 replaces the relay device 20-1 to the relay device 20-n with the relay device 20-1-1, the relay device 20-1-2, ... It is confirmed whether the individual packets transmitted to each of the device 20-n-1, the relay device 20-n-2, ... Satisfy the aggregation condition. Then, the processor 31 is any of the individual packets transmitted to the relay device 20-1-1, the relay device 20-1-2, ... To the relay device 20-n-1, the relay device 20-n-2, ... Depending on the aggregation condition, the relay device 20 satisfying the aggregation condition is subjected to the same processing as in steps S345 and S346.

The operation of the communication system 1b according to the third embodiment will be further described with reference to FIGS. 24 to 26. Each of FIGS. 24 to 26 is a sequence diagram showing an example of the information flow of the communication system 1b. Note that FIGS. 24 to 26 do not cover the flow of information in the communication system 1b, and a flow of information (not shown) may exist.

FIG. 24 shows an example of a communication sequence when there is no abnormality in the relay device 20-k-1.
The terminal device 10-k-1 and the terminal device 10-k-2 initially transmit the individual packet D3 to the relay device 20-k-1. Here, the relay device 20-k to which the terminal device 10-k transmits individual packets is set in advance by, for example, the administrator of the terminal device 10-k. Alternatively, the relay device 20-k to which the terminal device 10-k transmits individual packets may be the relay device 20-k having the earliest activation time. The subsequent communication sequence is the same as the communication sequence of the first embodiment. That is, the relay device 20-k-1 transmits the aggregated packet D4 to the server device 30. Then, the relay device 20-k-1 transmits the diagnostic packet D5 to the terminal device 10-k-1 and the terminal device 10-k-2. After that, the server device 30 transmits the aggregated packet D6 to the relay device 20-k-1. Then, the relay device 20-k-1 transmits the individual packet D7 to the terminal device 10-k-1 and the terminal device 10-k-2. In this case, the relay device 20-k-2 is on standby, and for example, the second diagnostic packet is transmitted to each terminal device 10-k at regular intervals.

FIG. 25 shows an example of a communication sequence when an abnormality occurs in the relay device 20-k-1.
The terminal device 10-k-1 and the terminal device 10-k-2 initially transmit the individual packet D3 to the relay device 20-k-1. At this time, it is assumed that the relay device 20-k-1 cannot transmit the aggregated packet D4 and the diagnostic packet D5 due to the occurrence of an abnormality. Therefore, the terminal device 10-k-1 and the terminal device 10-k-2 cannot receive the diagnostic packet D5. Therefore, the terminal device 10-k-1 and the terminal device 10-k-2 determine that an abnormality has occurred in the relay device 20-k-1, and transmit the individual packet D3 to the relay device 20-k-2. do. After that, the relay device 20-k-2 aggregates the individual packets and transmits the aggregated packet D4 to the server device 30. Then, the server device 30 transmits the aggregated packet D6 to the relay device 20-k-2. The relay device 20-k-2 that has received the aggregated packet D6 divides the aggregated packet D6 into individual individual packets D7. Then, the relay device 20-k-2 transmits the individual packet D7 to the terminal device 10-k-1 and the terminal device 10-k-2.

FIG. 26 shows an example of a communication sequence when the load of the relay device 20-k-1 is high.
The terminal device 10-k-1 and the terminal device 10-k-2 initially transmit the individual packet D3 to the relay device 20-k-1. Here, it is assumed that the load of the relay device 20-k-1 is 50%. Since the relay device 20-k-1 has a high load, the diagnostic packet D5 does not include the individual packet header D51 and the individual packet data D43 corresponding to the ID and sequence number of the terminal device 10-k-2. It is assumed that the aggregated packet D4 is generated. The diagnostic packet D5 and the aggregated packet D4 include an individual packet header D51 having an ID and a sequence number of the terminal device 10-k-1 and an individual packet data D43. The relay device 20-k-1 transmits the generated diagnostic packet D5 and the aggregated packet D4. Since the terminal device 10-k-1 has an individual packet header having a terminal ID of 1 in the diagnostic packet D5, it can be determined that the individual packet D3 is transmitted via the relay device 20-k-1. On the other hand, the terminal device 10-k-2 determines that the individual packet D3 has not been transmitted from the relay device 20-k-1 because the diagnostic packet D5 does not have an individual packet header with a terminal ID of 2, and sets the individual packet D3. It is transmitted to the relay device 20-k-2. After that, the relay device 20-k-2 aggregates the individual packets and transmits the aggregated packet D10 to the server device 30. The server device 30 aggregates the responses to the aggregated packet D4 and transmits them to the relay device 20-k-1, and aggregates the responses to the individual packets D3 included in the aggregated packet D10 and transmits them to the relay device 20-k-2. .. The data structure of the aggregated packet D10 is, for example, the same as that of the aggregated packet D4.

The relay device 20-k-1 in FIGS. 24 to 26 is an example of the first relay device. The relay device 20-k-2 in FIGS. 24 to 26 is an example of the second relay device.

According to the communication system 1b of the third embodiment, since the relay device 20 is multiplexed, packets can be aggregated by using another relay device 20 even if an abnormality occurs in the relay device 20. Is. Further, as a result, even if there is an abnormality in the relay device 20, the communication load of the server device 30 can be reduced.
According to the communication system 1b of the third embodiment, when the terminal device 10 determines that the relay device 20 has an abnormality, the terminal device 10 transmits an individual packet to the other relay device 20. This enables multiplexing of the relay device 20.

[Fourth Embodiment]
Hereinafter, the communication system according to the fourth embodiment will be described.
Since the configuration of the communication system 1b according to the fourth embodiment is the same as that of FIGS. 1 and 22 of the third embodiment, the description thereof will be omitted. Further, since the functional configuration of each device included in the communication system 1b according to the fourth embodiment is the same as that of FIG. 17 of the third embodiment, the description thereof will be omitted.

Hereinafter, the operation of the communication system 1b according to the fourth embodiment will be described with reference to FIGS. 8, 9, 11, 11, 13, 20, and 27. The content of the process in the following operation description is an example, and various processes capable of obtaining the same result can be appropriately used. In the fourth embodiment, the terminal device 10 performs the processes shown in FIGS. 27 and 8 instead of the processes shown in FIGS. 19 and 8 of the second embodiment. FIG. 27 is a flowchart of processing by the processor 11 of the terminal device 10. The processor 11 executes this process based on a program stored in the ROM 12 or the auxiliary storage device 14. The processor 11 simultaneously processes the processes shown in FIGS. 27 and 8 in parallel or in parallel. The relay device 20 performs the processes shown in FIGS. 9 and 20 as in the second and third embodiments. Further, the server device 30 performs the processes shown in FIGS. 11 to 13 in the same manner as in the first to third embodiments.

In the fourth embodiment, the processor 11 proceeds to step S151 after the process of step S112 of FIG. 27.
In step S151, the processor 11 sends an individual packet destined for the server device 30 to all the relay devices 20 in the same area A as the area A where the terminal device 10 is installed in the second communication I / F16. Instruct. In response to this instruction, the second communication I / F 16 transmits the individual packet to each relay device 20. The transmitted individual packet is received by the communication I / F 25 of each relay device 20. At this time, for example, the processor 11 cancels the registration of the individual packet in the processing buffer.

In the fourth embodiment, if the processor 11 determines No in step S131 of FIG. 27, the processor 11 proceeds to step S152.
In step S152, the processor 11 determines whether or not the first diagnostic packet has been received from all of the relay devices 20 to which the individual packets transmitted in step S151 are transmitted. If the processor 11 has not received the first diagnostic packet from all of the relay devices 20 in the same area A, the processor 11 determines No in step S152 and returns to step S115. On the other hand, if the processor 11 receives the first diagnostic packet from all of the relay devices 20 in the same area A, the processor 11 determines Yes in step S152 and proceeds to step S116.

In the fourth embodiment, the processor 31 of the server device 30 replaces the relay device 20-1 to the relay device 20-n with the relay device 20-1-1, the relay device 20-1-2, ... It is confirmed whether the individual packets transmitted to each of the device 20-n-1, the relay device 20-n-2, ... Satisfy the aggregation condition. Then, the processor 31 is any of the individual packets transmitted to the relay device 20-1-1, the relay device 20-1-2, ... To the relay device 20-n-1, the relay device 20-n-2, ... Depending on the aggregation condition, the relay device 20 satisfying the aggregation condition is subjected to the same processing as in steps S345 and S346.

The operation of the communication system 1b according to the fourth embodiment will be further described with reference to FIGS. 28 and 29. Each of FIGS. 28 and 29 is a sequence diagram showing an example of the information flow of the communication system 1b. Note that FIGS. 28 and 29 do not cover the flow of information in the communication system 1b, and there may be a flow of information (not shown).

FIG. 28 shows an example of a communication sequence when there is no abnormality in the relay device 20-k-1 and the relay device 20-k-2.
The terminal device 10-k-1 and the terminal device 10-k-2 each transmit the individual packet D3 to both the relay device 20-k-1 and the relay device 20-k-2. After that, the relay device 20-k-1 that has received the individual packet D3 transmits the aggregated packet D4 to the server device 30, and transmits the diagnostic packet D5 to the terminal device 10-k-1 and the terminal device 10-k-2. .. Further, the relay device 20-k-2 that has received the individual packet D3 transmits the aggregated packet D10 to the server device 30, and transmits the diagnostic packet D9 to the terminal device 10-k-1 and the terminal device 10-k-2. .. The data structure of the diagnostic packet D9 is, for example, the same as that of the diagnostic packet D5.
The server device 30 reads the terminal ID and sequence number of the individual packet of the aggregated packet D4 by the reception selection unit 303, confirms that the individual packet has not been received, and performs a determination process. After that, when the aggregated packet D10 is received, the reception selection unit 303 reads the terminal ID and sequence number of the individual packet of the aggregated packet D10, confirms that it is a received individual packet, and discards the packet. Since the server device 30 generates the control signal D2 from the detection signal D1 stored in the aggregate packet D4 received from the relay device 20-k-1, the server device 30 transmits the aggregate packet D6 transmitted from the server device 30 to the relay device 20-k-. Send to 1.

FIG. 29 shows an example of a communication sequence when an abnormality occurs in the relay device 20-k-1.
The terminal device 10-k-1 and the terminal device 10-k-2 each transmit the individual packet D3 to both the relay device 20-k-1 and the relay device 20-k-2. After that, the relay device 20-k-2 that has received the individual packet D3 transmits the aggregated packet D10 to the server device 30, and transmits the diagnostic packet D9 to the terminal device 10-k-1 and the terminal device 10-k-2. ..
The server device 30 reads the terminal ID and sequence number of the individual packet of the aggregated packet D10 by the reception selection unit 303, confirms that the individual packet has not been received, and performs a determination process. Since the server device 30 generates the control signal D2 from the detection signal D1 stored in the aggregate packet D10 received from the relay device 20-k-2, the server device 30 transmits the aggregate packet D6 transmitted from the server device 30 to the relay device 20-k-. Send to 2.

According to the communication system 1b of the fourth embodiment, the terminal device 10 transmits individual packets to a plurality of relay devices 20. Therefore, even if an abnormality occurs in a part of the relay device 20 which is the destination of the individual packet, the other relay device 20 which is the destination of the individual packet aggregates the individual packet and transmits the individual packet to the server device 30. .. As a result, even if an abnormality occurs in the relay device 20, the individual packet arrives at the communication server without the terminal device 10 retransmitting the individual packet. Further, the server device 30 discards the same individual packets transmitted from the plurality of relay devices 20 except for the first arriving packet. From the above, the communication system 1b of the fourth embodiment can prevent a delay in the transmission time when an abnormality occurs in the relay device 20.

The first to fourth embodiments can be modified as follows.
The terminal device 10 may periodically make an inquiry to the relay device 20 to confirm whether or not communication can be performed normally. Then, when the terminal device 10 cannot communicate normally, the transmission destination of the individual packet may be changed to another relay device 20 or a server device 30.

When the terminal device 10 determines that the relay device 20 has an abnormality, the terminal device 10 may periodically make an inquiry to the relay device 20 to confirm whether the relay device 20 has returned to normal operation.

In the fourth embodiment, the terminal device 10-k sends the individual packet to a part of the relay devices 20-k among the plurality of relay devices 20-k instead of all the relay devices 20-k in the area Ak. You may send it. Then, when the terminal device 10-k determines that the individual packet has not been transmitted to the server device 30 in any of the relay devices 20-k, the terminal device 10-k does not transmit the individual packet among the plurality of relay devices 20-k. It may be transmitted to a part or all of the relay device 20-k.

In the first to fourth embodiments, the regions are divided into regions such as region A1, region A2, ..., Region An. However, this division is not limited to each region. For example, this delimiter may be divided into units such as an organization.

The communication system 1 and the communication system 1b may include other devices such as a PC instead of the server device 30. The other device operates in the same manner as the server device 30. The other device is an example of a communication device.

Each device in the first to fourth embodiments may be a device composed of a plurality of devices. Further, a part of the device may be realized by cloud computing.

Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other embodiments, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are also included in the scope of the invention described in the claims and the equivalent scope thereof.
Hereinafter, the inventions described in the claims at the time of filing the application of the present application will be added.
[C1]
The first individual packet is sent to one or more destinations selected from a destination group consisting of a communication device, one or more relay devices that relay transmission of a first individual packet destined for the communication device, and a destination group. The first communication unit to send and
A second communication unit that receives a diagnostic packet indicating the operation of the relay device, and
The first relay device is selected as the transmission destination of the first individual packet, and the diagnostic packet is not received or is included in the diagnostic packet after the transmission of the first individual packet to the first relay device. A terminal device including a control unit that selects a device other than the first relay device included in the destination group as a transmission destination when a non-transmission of the first individual packet is detected based on a transmission record. ..
[C2]
The terminal device according to [C1], wherein the control unit selects a second relay device as a device other than the first relay device.
[C3]
The terminal device according to [C1], wherein the control unit selects a first relay device and a second relay device as a transmission destination of the first individual packet.
[C4]
The input section where the detection signal is input and
Further provided with an output unit that outputs a control signal corresponding to the detection signal.
The second communication unit receives the second individual packet corresponding to the first individual packet, and receives the second individual packet.
The first individual packet includes the detection signal.
The terminal device according to any one of [C1] to [C3], wherein the second individual packet includes the control signal.
[C5]
A first communication unit that receives individual packets destined for the communication device from the terminal device, and
A processing unit that aggregates the individual packets to generate an aggregated packet and generates a diagnostic packet containing information regarding the transmission of the aggregated packet.
A second communication unit that transmits the aggregated packet to the communication device, and
A relay device including a third communication unit that transmits the diagnostic packet to the terminal device.
[C6]
It also has a load measurement unit that measures the load.
The processing unit
When the load measured by the load measuring unit is equal to or greater than the reference value, some or all of the individual packets received by the first communication unit are not aggregated.
The relay device according to [C5], which generates the diagnostic packet including information about not aggregating a part or all of the individual packets.
[C7]
A first communication unit that receives a first individual packet including a detection signal transmitted from a terminal device and a first aggregated packet transmitted from a relay device in which the first individual packet is aggregated. When,
In response to the reception of the first individual packet, a second individual packet including a control signal corresponding to the detection signal is generated.
In response to the reception of the first aggregated packet, the second individual packet generates a second aggregated packet in which the second individual packet is aggregated.
Generator and
A communication device including a second communication unit that transmits the second individual packet to the terminal device and transmits the second aggregated packet to the relay device.
[C8]
Includes a terminal device and one or more relay devices that relay the transmission of a first individual packet destined for a communication device.
The terminal device is
A first terminal communication unit that transmits the first individual packet to one or more destinations selected from a destination group consisting of the communication device and one or more relay devices.
A control unit that selects a first relay device as a transmission destination of the first individual packet is provided.
The relay device is
The first relay communication unit that receives the first individual packet and
A processing unit that aggregates the first individual packet to generate an aggregated packet and generates a diagnostic packet containing information regarding transmission of the aggregated packet.
A second relay communication unit that transmits the aggregated packet to the communication device, and
A third relay communication unit that transmits the diagnostic packet to the terminal device is provided.
The terminal device is
A second terminal communication unit that receives the diagnostic packet is further provided.
The control unit may not receive the diagnostic packet after the transmission of the first individual packet to the first relay device, or may not transmit the first individual packet based on a transmission record included in the diagnostic packet. A communication system that, when detected, selects a device other than the first relay device included in the destination group as a transmission destination.
[C9]
The terminal device sets the first relay device from the destination group including the communication device and one or more relay devices that relay the transmission of the first individual packet destined for the communication device. Select as the destination for the packet and
The terminal device transmits the first individual packet to the first relay device.
The relay device receives the first individual packet and receives the first individual packet.
The relay device aggregates the first individual packet to generate an aggregated packet.
The relay device generates a diagnostic packet containing information regarding the transmission of the aggregated packet, and the relay device transmits the aggregated packet to the terminal device.
The relay device transmits the aggregated packet to the communication device, and the relay device transmits the aggregated packet to the communication device.
When the terminal device detects the non-receipt of the diagnostic packet after the transmission of the first individual packet or the non-transmission of the first individual packet based on the transmission record included in the diagnostic packet, the transmission destination. A communication method for selecting a device other than the first relay device included in the group as a transmission destination.
[C10]
The computer that the terminal device has
From a destination group consisting of a communication device and one or more relay devices that relay the transmission of the first individual packet destined for the communication device, the first relay device is the transmission destination of the first individual packet. The non-reception of the diagnostic packet after the transmission of the first individual packet to the first relay device or the non-transmission of the first individual packet is detected based on the transmission record included in the diagnostic packet. In this case, a device other than the first relay device included in the destination group is selected as the transmission destination.
A program that functions as a control unit.
[C11]
The computer that the relay device has
Individual packets received from the terminal device and destined for the communication device are aggregated to generate an aggregated packet, and a diagnostic packet containing information regarding the transmission of the aggregated packet is generated.
Controlled to transmit the aggregated packet to the communication device
Controlling the diagnostic packet to be transmitted to the terminal device,
A program that functions as a processing unit.
[C12]
Computers equipped with communication devices
In response to the reception of the first individual packet including the detection signal transmitted from the terminal device, the second individual packet including the control signal corresponding to the detection signal is generated.
In response to the reception of the first aggregated packet in which the first individual packet is aggregated, which is transmitted from the relay device, the second aggregated packet in which the second individual packet is aggregated is generated.
The second individual packet is transmitted to the terminal device, and the second aggregated packet is controlled to be transmitted to the relay device.
A program that functions as a generator.

1 ... Communication system, 10 ... Terminal device, 11,21,31 ... Processor, 12,22,32 ... ROM, 13,23,33 ... RAM, 14,24,34 ... Auxiliary storage device, 15 ... 1st communication I / F, 16 ... 2nd communication I / F, 20 ... relay device, 25, 35 ... communication I / F, 30 ... server device, 101 ... input unit, 102, 305 ... ID addition unit, 103, 306 ... destination selection unit, 104 ... transmission unit, 105, 201 ... first receiving unit, 106 ... diagnostic unit, 107, 207 ... second receiving unit , 108 ... ID confirmation unit, 109, 303 ... reception selection unit, 110 ... output unit, 121 ... abnormality notification unit, 202, 308 ... aggregation unit, 203, 309 ... aggregation packet generation unit, 204, 307 ... 1st transmitter, 205 ... Diagnostic packet generator, 206, 310 ... 2nd transmitter, 208, 302 ... Separation, 209 ... 3rd transmitter, 221 ... Load measurement, 301 …… Receiver, 304 …… Judgment, DA …… Controlled device

Claims (3)

The first individual packet is sent to one or more destinations selected from a destination group consisting of a communication device, one or more relay devices that relay transmission of a first individual packet destined for the communication device, and a destination group. The first communication unit to send and
A second communication unit that receives a diagnostic packet indicating the operation of the relay device, and
The first relay device is selected as the transmission destination of the first individual packet, and the diagnostic packet is not received or is included in the diagnostic packet after the transmission of the first individual packet to the first relay device. When a non-transmission of the first individual packet is detected based on the transmission record, a control unit that selects a device other than the first relay device included in the destination group as a transmission destination, and a control unit.
The input section where the detection signal is input and
It is provided with an output unit that outputs a control signal corresponding to the detection signal.
The second communication unit receives the second individual packet corresponding to the first individual packet, and receives the second individual packet.
The first individual packet includes the detection signal.
The second individual packet is a terminal device including the control signal. The terminal device according to claim 1, wherein the control unit selects a second relay device as a device other than the first relay device. The terminal device according to claim 1, wherein the control unit selects a first relay device and a second relay device as a transmission destination of the first individual packet.

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