Terminal device and message transmission method

Abstract

A terminal device according to one embodiment of the present invention comprises: an acquisition unit that acquires a first message for a partner designated as a destination; a collection unit that collects information on one or more other terminals present within a range in which short-range wireless communication is possible; and a first transmission unit that transmits the first message to a first terminal selected on the basis of the information from among the one or more other terminals via the short-range wireless communication.

Description

Terminal device and message transmission method

[0001] The present invention relates to a terminal device and a message transmission method.

[0002] A communication technology between terminals using short-range communication is known. For example, Patent Document 1 discloses an invention that enables terminals to share information via short-range wireless communication when mobile communication terminals in a disaster area are out of communication range due to a malfunction or the like during a disaster such as an earthquake.

[0003] JP 2009-124448 A

[0004] The technology described in Patent Document 1 is limited to sharing disaster information such as text or photos showing the disaster situation.

[0005] In response to this, the present invention provides a technique for delivering a message to a designated recipient even in a situation where a public network is unavailable.

[0006] One aspect of the present disclosure provides a terminal device having an acquisition unit that acquires a first message addressed to a party designated as a destination, a collection unit that collects information about one or more other terminals within a range where short-range wireless communication is possible, and a first transmission unit that transmits the first message from the one or more other terminals to a first terminal selected based on the information via the short-range wireless communication.

[0007] Another aspect of the present disclosure provides a message sending method including the steps of obtaining a first message for a party designated as a destination, collecting information on one or more other terminals within a range where short-range wireless communication is possible, and sending the first message from the one or more other terminals to a first terminal selected based on the information via the short-range wireless communication.

[0008] According to the present invention, a message can be delivered to a designated recipient even when a public network is unavailable.

[0009] 1 is a diagram illustrating an example of the system configuration of a message relay system 1. FIG. 2 is a diagram illustrating an example of the functional configuration of the message relay system 1. FIG. 3 is a diagram illustrating an example of the hardware configuration of a terminal device 10. FIG. 4 is a sequence chart illustrating a network connection in a coverage area. FIG. 5 is a diagram illustrating a base station database. FIG. 6 is a sequence chart illustrating a method of collecting terminal information. FIG. 7 is a sequence chart illustrating message transmission by a transmitting terminal. FIG. 8 is a diagram illustrating a transmitted message database. FIG. 9 is a diagram illustrating a relay message database. FIG. 10 is a sequence chart illustrating message relay by a relay terminal. FIG. 11 is a sequence chart illustrating message reception by a receiving terminal. FIG. 12 is a diagram illustrating relay processing in a public network. FIG. 13 is a diagram illustrating an outline of a method of transmitting route information. FIG. 14 is a diagram illustrating an outline of a method of transmitting arrival confirmation.

[0010] 1. Configuration FIG. 1 illustrates the system configuration of a message relay system 1. In this example, the message relay system 1 (or simply referred to as the system) is a system for transmitting and receiving messages from a user's terminal device (or simply referred to as the terminal) to another terminal in an out-of-service area where a public network cannot be connected, using direct wireless communication between terminals (hereinafter referred to as "short-range wireless communication"). Short-range wireless communication refers to direct communication between two devices without a repeater or network, such as wireless communication performed according to standards such as Wi-Fi Direct or Bluetooth. The communication distance according to these standards is approximately several tens of meters to 100 meters, and is sometimes referred to as short-range communication. An out-of-service area (or simply referred to as "out-of-service area") refers to an area (e.g., a disaster area) where access to the public network is blocked due to network failure caused by damage to base station equipment due to a disaster (such as an earthquake). An in-service area (or simply referred to as "in-service area") refers to an area where base stations are functioning normally and terminals have network connectivity. The base station is a wireless base station equipped with an antenna for performing mobile communications in accordance with a predetermined communication standard (e.g., LTE or 5G). The message relay system 1 includes a terminal device 10, a terminal device 20, and a terminal device 30.

[0011] Terminal device 10, terminal device 20, and terminal device 30 basically have the same functions for sending and receiving messages. For ease of explanation, the terminal that sends a message will be referred to as terminal device 10, the relay terminal that relays the message will be referred to as terminal device 20, and the destination terminal of the message will be referred to as terminal device 30. There may be multiple relay terminals, and when distinguishing between the multiple relay terminals, subscripts such as terminal device 20A, 20B, 20C, etc. will be used. When there is no need to distinguish between them, they will simply be referred to as terminal device 20. In this document, "destination" refers to the final destination specified by the sender of a message. Furthermore, "destination" refers to the device that receives data when data is sent from one device to another.

[0012] In this example, each component of the system has various network configurations depending on whether it belongs to an out-of-service area or an in-service area. Each terminal connects via short-range wireless communication 91 and / or a public network 92, as shown in FIG. 1 . In an out-of-service area, base station 81 is not functioning, so each terminal forms a network formed by connecting with other terminals via short-range wireless communication 91. On the other hand, in an in-service area, base station 82 is functioning normally, so each terminal can connect to public network 92 via base station 82. In this example, public network 92 is a computer network such as the Internet or a mobile network. Some terminals in the out-of-service area (terminal device 20N in the example of FIG. 1 ) communicate with some terminals in the in-service area (terminal device 20Z in the example of FIG. 1 ) via short-range wireless communication.

[0013] In recent years, messaging services such as SMS (Short Message Service) and messaging apps have become widespread, making it possible to quickly confirm the safety of people even during disasters. However, if a network failure occurs due to a disaster or other reason, and the area where the victim is located is out of service, communication means may be cut off, making it impossible to report the victim's safety to a distant location or to call for rescue. Therefore, in this embodiment, even in a situation where the terminals cannot connect to a public network, the terminals are wirelessly connected to each other via short-range wireless communication to relay messages, enabling the transmission and reception of messages between terminals within the service area.

[0014] In the message relay system 1, the terminal device 10 (transmitting terminal) is a source terminal device (also referred to as a user terminal) that transmits a message (an example of a first message) in an out-of-service area. The terminal device 10 includes, for example, a smartphone, a tablet, or a personal computer. In this example, the terminal device 10 receives an instruction from a user to transmit a message (an example of a first message) to a party designated as a destination. Because it is difficult to use mobile network communication via a public network 92 in an out-of-service area, the terminal device 10 connects to another terminal within a range where short-range wireless communication is possible via short-range wireless communication 91. The terminal device 10 transmits a message addressed to the destination to the other connected terminal.

[0015] Terminal device 20 (relay terminal) relays a message received from one terminal to another terminal in message relay system 1. Terminal device 20 not only relays a message received directly from terminal device 10, which is the sender of the message, to other terminal devices 20, but also receives a message (an example of a second message) received via short-range wireless communication from a terminal device 20 other than the sender of the message, and relays the message to a specified destination.

[0016] Like the terminal device 10, the terminal device 20 includes a smartphone, tablet, or personal computer. In this example, the terminal device 20 (including terminal devices 20A to 20Z) performs different processing on received messages depending on whether it is in an area with no service area or an area with service area. When the terminal device 20 (e.g., terminal devices 20A to 20N) is in an area with no service area and mobile network communication is difficult to use, the terminal device 20 connects to another terminal within the range of short-range wireless communication and transmits the message received from the sender to the other connected terminal. On the other hand, when the terminal device 20 (e.g., terminal device 20Z) is in an area with service area and mobile network communication is available, the terminal device 20 accesses the public network 92 and transmits the message directly to the destination terminal.

[0017] The terminal device 30 (receiving terminal) is a terminal device in the message relay system 1 that receives a message addressed to a destination specified by a sender. Like the terminal device 10, the terminal device 30 includes a smartphone, a tablet, or a personal computer. In this example, the terminal device 30 can use the public network 92 in an area within the service area, and therefore can receive a message via the public network 92. Alternatively, if the terminal device 30 itself is out of service area due to the operating status of a base station, the terminal device 30 receives a message from the terminal device 20 via short-range wireless communication 91.

[0018] Regarding the distinction between the first message and the second message, the term "message" described below includes both or either the first message or the second message.

[0019] 2 is a diagram illustrating an example of the functional configuration of the message relay system 1. In this embodiment, the same application program is installed on the terminal device 10, the terminal device 20, and the terminal device 30, and these devices have the same functions for sending and receiving messages. Therefore, only the terminal device 10 will be described here. In this example, the functions of the terminal device 10 are implemented by an SMS application and a relay application. The SMS application is a general-purpose application program that allows the sender to input a message and issue a transmission instruction. The relay application is an application program dedicated to the message relay system 1 that requests another terminal to relay a message via short-range wireless communication.

[0020] When the SMS application cannot send a message via public network 92 because the SMS application is out of range, the relay application can obtain the message from the SMS application. At the receiving terminal, the data of the message received by the relay application is restored and displayed in the SMS application. In other words, the relay application allows data exchange between users in the same way as when messages are sent and received between SMS applications. In message relay system 1, the SMS application and the relay application work together to perform processing.

[0021] The terminal device 10 has, as a transmitting terminal function, functional blocks (components) including an acquisition unit 11, a collection unit 12, a first transmission unit 13, and a first reception unit 14. The terminal device 10 also has, as a relay / receiving terminal function, functional blocks including a second reception unit 21, a first determination unit 22, a second transmission unit 23, an addition unit 24, a second determination unit 31, and a reception processing unit 32. The terminal device 10 also has a memory unit 18 as a function common to the transmitting terminal function and the relay / receiving terminal function (and other application programs). The above functions are implemented by a relay app.

[0022] The terminal device 10 has a reception unit 15. The reception unit 15 is implemented by an SMS application. The reception unit 15 receives input of a message body and a transmission instruction from a user. Furthermore, the terminal device 10 has a control unit 19. The control unit 19 performs various controls. The control unit 19 may be a function of a relay application, a function of an SMS application, or a function of neither application. First, a functional block related to the transmission terminal function will be described.

[0023] The acquisition unit 11 acquires a first message for a party designated as a destination. In this example, the acquisition unit 11 acquires a message for which the acceptance unit 15 has accepted an input and a transmission instruction from the acceptance unit 15. Here, a situation is assumed in which a user in an out-of-service area attempts to send a message (an example of a first message) to a partner user in an in-service area.

[0024] The collection unit 12 collects information (hereinafter referred to as "terminal information") about one or more other terminals (so-called "mobile communication terminals") within a range where short-range wireless communication is possible. This allows the terminal device 10 to search for nearby terminals.

[0025] The first transmitter 13 transmits a first message via short-range wireless communication to a first terminal (such as a nearby terminal device 20) selected from one or more other terminals based on the terminal information. The terminal information is information about the other terminals, and includes identification information and location information of the other terminals. The location information is information about the cell that was last located in the record of the other terminals (hereinafter referred to as the "last cell"), and includes, for example, a cell ID, a location time (the time when the terminal was connected to the base station), and location information.

[0026] The first receiving unit 14 receives an arrival confirmation from one of the one or more other terminals indicating that the first message has reached its destination (after being relayed by one or more terminal devices). If the arrival confirmation is not received by the terminal device 10 (within a certain period of time), the first sending unit 13 transmits the first message to a second terminal other than the first terminal among the one or more other terminals.

[0027] The storage unit 18 stores various data and programs. In this example, the data stored in the storage unit 18 includes terminal information and arrival confirmation.

[0028] Next, functional blocks related to the relay terminal function and the receiving terminal function will be described. The second receiving unit 21 receives a second message with a specified destination from one or more other terminals via short-range wireless communication. The second message is, for example, a message transmitted from terminal device 10 to terminal device 20 via short-range wireless communication. The first determining unit 22 determines whether the local device can connect to a public network. If the local device can connect to the public network, the second transmitting unit 23 transmits the second message via the public network. On the other hand, if the local device cannot connect to the public network, the second transmitting unit 23 transmits the second message via short-range wireless communication to a third terminal (such as another nearby terminal device 20) selected based on information from one or more other terminals. The adding unit 24 adds identification information of the local device to the second message. The identification information includes, for example, a MAC address for each terminal. The second transmitting unit 23 transmits the second message to which the identification information has been added by the adding unit 24. The second determining unit 31 determines whether the second message is addressed to the local device. The relay terminal or the receiving terminal determines the destination of the received message, thereby enabling forwarding or receiving processing. If it is determined that the second message is addressed to the relay terminal or the receiving terminal, the receiving processing unit 32 performs receiving processing of the second message.

[0029] The second message includes route information indicating the route of the terminal devices that relayed the second message. The route information is information indicating which terminals the message was relayed between in the message relay system 1.

[0030] The receiving processing unit 32 sends a confirmation of arrival of the message to the sender of the second message, indicating that the message has reached the device itself, by tracing back the route indicated by the route information included in the second message.

[0031] FIG. 3 is a diagram illustrating an example of the hardware configuration of the terminal device 10. The terminal device 10 is physically configured as a computer including a processor 101, a memory 102, a storage 103, a communication device 104, an input device 105, a display device 106, and a bus connecting these devices. Each of these devices operates using power supplied from a battery (not shown). In the following description, the term "device" can be interpreted as a circuit, a device, a unit, or the like. The hardware configuration of the terminal device 10 may be configured to include one or more of the devices shown in FIG. 3, or may be configured without including some of the devices. Furthermore, the terminal device 10 may be configured by communicating and connecting multiple devices each having a different housing.

[0032] Each function of the terminal device 10 is realized by loading specified software (programs) onto hardware such as the processor 101 and memory 102, causing the processor 101 to perform calculations, control communication via the communication device 104, and control at least one of reading and writing data in the memory 102 and storage 103.

[0033] The processor 101 controls the entire computer by running, for example, an operating system. The processor 101 may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc. Furthermore, for example, a baseband signal processing unit, a call processing unit, etc. may be realized by the processor 101.

[0034] The processor 101 reads programs (program codes), software modules, data, etc. from at least one of the storage 103 and the communication device 104 into the memory 102, and executes various processes in accordance with these. The programs used are those that cause a computer to execute at least some of the operations described below. The functional blocks of the terminal device 10 may be implemented by a control program stored in the memory 102 and running on the processor 101. Various processes may be executed by one processor 101, or may be executed simultaneously or sequentially by two or more processors 101. The processor 101 may be implemented by one or more chips. The programs may be transmitted to the terminal device 10 via a telecommunications line.

[0035] The memory 102 is a computer-readable recording medium and may be configured by, for example, at least one of a read-only memory (ROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a random access memory (RAM), etc. The memory 102 may also be called a register, a cache, a main memory (primary storage device), etc. The memory 102 can store executable programs (program codes), software modules, etc. for implementing the method according to this embodiment.

[0036] Storage 103 is a computer-readable recording medium, and may be composed of at least one of, for example, an optical disk such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disk, a digital versatile disk, a Blu-ray (registered trademark) disk), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy (registered trademark) disk, a magnetic strip, etc. Storage 103 may also be called an auxiliary storage device.

[0037] The communication device 104 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also called, for example, a network device, a network controller, a network card, or a communication module.

[0038] Each device, such as the processor 101 and the memory 102, is connected by a bus for communicating information. The bus may be configured using a single bus, or different buses may be used between each device.

[0039] The terminal device 10 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized by the hardware. For example, the processor 101 may be implemented using at least one of these pieces of hardware.

[0040] In this example, the programs stored in storage 103 include an application program for inputting and outputting messages and an application program for transmitting these messages to other terminals. The application program for inputting and outputting messages is, for example, a general-purpose SMS sending and receiving program (hereinafter referred to as an "SMS application"). The application program for transmitting messages to other terminals is a program dedicated to this process (hereinafter referred to as a "relay application"), and works in conjunction with the SMS application (see the software configuration in FIG. 2).

[0041] When the processor 101 is executing the SMS app or the relay app, the processor 101, the memory 102, the storage 103, and the communication device 104 are examples of functional blocks for operating the terminal device 10. When the processor 101 is executing the SMS app, the processor 101 is an example of the accepting unit 15. When the processor 101 is executing the relay app, the processor 101 is an example of the acquiring unit 11, the collecting unit 12, the control unit 19, the first determining unit 22, the adding unit 24, the second determining unit 31, and the receiving processing unit 32. At least one of the memory 102 and the storage 103 is an example of the storage unit 18. The communication device 104 is an example of the first transmitting unit 13, the first receiving unit 14, the second receiving unit 21, and the second transmitting unit 23.

[0042] Terminal device 20 and terminal device 30 have a common hardware configuration with terminal device 10. With regard to the hardware configuration of terminal device 20 or terminal device 30, when the processor is executing various programs, the processor, memory, storage, and communication device are examples of functional blocks for operating terminal device 20 or terminal device 30. The configuration of message relay system 1 has been described above. Next, the operation of message relay system 1 will be described.

[0043] 2. Operation The operation of the message relay system 1 will now be described. Here, an example will be described in which a message is input and sent in the form of a so-called SMS message. The public network 92 is a network for sending and receiving SMS, i.e., a mobile network.

[0044] 4 is a sequence chart illustrating a network connection in a coverage area. It is assumed here that no base station failure due to a disaster or the like has occurred, and the terminal device 10 can communicate with the base station 81 (i.e., the public network 92 is available). In step S11, the terminal device 10 wirelessly accesses the base station 81.

[0045] In step S12, the base station 81 acquires its own base station information. The base station information (an example of information) is information indicating a cell ID managed by the base station, unique identification information, and location information (for example, an address or coordinates) of the location of the base station.

[0046] In step S13, the base station 81 transmits its own base station information to the terminal device 10 connected to the base station 81. The base station 81 may transmit the base station information when transmitting data to the terminal device 10.

[0047] In step S14, the terminal device 10 acquires the base station information of the currently connected base station 81 and records it in a database. The terminal device 10 acquires the base station information at a specific period. Alternatively, when the connected base station is changed due to the terminal moving, for example, the terminal device 10 acquires the base station information of the newly connected base station. Here, the database for managing base station information will be described.

[0048] FIG. 5 is a diagram illustrating a base station database. In this example, the base station database 1001 includes multiple records. Each record corresponds to a record for each time (timestamp). Each record includes a timestamp, base station information, base station location information, and terminal location information. The timestamp is a record of the time when the terminal device 10 acquired the base station information. The base station information is identifiable information uniquely assigned to each base station, such as a CID (Cell ID), MCC (Mobile Country Code), MNC (Mobile Network Code), LAC (Location Area Code), or TAC (Tracking Area Code). The CID is a cell ID (unique ID) for each base station. The MCC is a code assigned to each country in which the base station is located (for example, 440 in Japan). The MNC is a code assigned to each telecommunications carrier that operates the network. The LAC or TAC is a code assigned to each area within the network range covered by the base station. The base station location information is location information such as the address or coordinates of the location of the base station. The terminal location information is information identifying the location of the terminal device 10 for each timestamp using GPS or the like. The base station information may be stored in a database of the terminal device 10, may be updated as appropriate, or may be deleted starting with the oldest data when the data exceeds a certain capacity. At least a part of the base station information may be treated as in-service information.

[0049] As a result, even if the terminal device 10 is unable to connect to the mobile network or the Internet due to a network failure or other reason, the terminal device 10 can continue to retain information about the base station to which it was connected immediately before the failure occurred (the terminal's own location information).

[0050] 2-1. Collection of Terminal Information Fig. 6 is a sequence chart illustrating the process of collecting terminal information in the message relay system 1. This process may be performed periodically while the base station 81 is functioning normally, or may be initiated in response to a network failure. This process is performed by each of the terminal device 10 and the terminal device 20 on which the relay app is running. Here, an example in which the terminal device 10 performs this process will be described.

[0051] In step S501, the relay app of the terminal device 10 searches for other terminals in the vicinity of the terminal device 10. This search is performed according to the standard of short-range wireless communication 91 that may be used (potentially) for message relay. In one example, the terminal device 10 scans for other terminals according to the standard of short-range wireless communication 91 and stores a list of other terminals that have been discovered. Note that the terminals scanned (or discovered) according to the standard of short-range wireless communication 91 may be outside or within range.

[0052] In step S502, the relay application of the terminal device 10 transmits an inquiry to one other terminal device 20 in accordance with the standard of the short-range wireless communication 91. The terminal device 20 to which the inquiry is to be transmitted is identified one by one from the list of other terminals in order.

[0053] The relay app of the terminal device 20 that received the inquiry refers to its own stored database and reads out the presence information and identification information (step S503). This process includes, for example, obtaining any data contained in the base station database 1001. This allows the terminal device 20 to obtain the cell ID and presence time of the base station to which it was last connected. The terminal device 20 transmits the terminal information to the terminal device 10 that sent the inquiry (step S504). The terminal information includes the presence information and identification information read out in step S503.

[0054] In step S505, the relay application of the terminal device 10 records the acquired terminal information in a database (terminal database). Furthermore, the terminal device 10 records information indicating the received radio wave intensity in the short-range wireless communication 91 with the terminal device 20 in a record of the corresponding terminal information in the terminal database.

[0055] The processes from step S502 to step S504 are repeatedly performed for the multiple terminals discovered in step S501.

[0056] As a result, the terminal device 10 can obtain the presence information of multiple terminals. By comparing the information, it is possible to determine the terminal that is closer to the coverage area and use this information for prioritizing message transmission. This process may be executed in combination with any of the processes described in Sections 2-2 to 2-6 below. This process may also be performed between terminals connected via the public network 92.

[0057] 2-2. Message Transmission by a Sending Terminal FIG. 7 is a sequence chart illustrating a message transmission process by a sending terminal in the message relay system 1. Here, it is assumed that the location of the user who owns the terminal device 10 has become an out-of-service area due to a network failure or the like. The operation of the terminal device 10 is divided into processing by the SMS app and the relay app. In step S101, the SMS app of the terminal device 10 accepts message input from the user. The user uses a UI provided by the SMS app to specify the recipient and input the message.

[0058] In step S102, the SMS application of the terminal device 10 receives a message sending instruction from the user. Specifically, after completing input of the message, the user presses a send button (not shown) displayed on the screen of the SMS application.

[0059] In step S103, the SMS app of the terminal device 10 checks connection to the public network 92 upon receiving a transmission instruction from the user. If connection to the public network 92 is possible, the SMS app accesses the public network 92 and sends a message. More specifically, the SMS app sends the message to a server that processes SMS messages (a so-called SMS center). This is the normal processing of the SMS app. If a message is sent via the public network 92, the processing described below is not performed for that message. The relay app of the terminal device 10 monitors the status of the SMS app. If connection to the public network 92 is impossible, the relay app of the terminal device 10 proceeds to the next step. Note that this processing may be omitted if network connection checks are performed periodically.

[0060] Therefore, in step S104, if connection to the public network 92 is not possible, the message is automatically forwarded from the SMS app of the terminal device 10 to the relay app. This may be processing by the relay app that monitors the status of the SMS app, forwarding processing by the SMS app, or a function of linking the SMS app and relay app that are linked in advance. Note that the data structure of the message forwarded from the SMS app to the relay app at this time is exactly the same.

[0061] In step S105, the relay app of the terminal device 10 identifies (or selects) other terminals to be relay terminals for the message. Specifically, the terminal device 10 identifies a predetermined number of other terminals to be relay terminals for the message from among multiple other terminals registered in the terminal database. The number of other terminals identified at one time is determined in the relay app (e.g., five). The relay app selects a predetermined number of other terminals from among the multiple other terminals registered in the terminal database in order of priority given by a predetermined criterion. In one example, the priority is given to terminals with stronger radio wave strength. Note that the relay app may narrow down the target terminals based on the type of terminal (smartphone, wireless earphones, or speaker) (e.g., excluding terminals other than smartphones).

[0062] In step S106, the relay app of the terminal device 10 transmits the message instructed by the user to the selected terminal via short-range wireless communication 91. In this example, the message transmitted via short-range wireless communication 91 has the same data structure as a message transmitted by normal SMS. That is, the message has a header and a body. The header includes information such as the message type, sender identification information, destination identification information, a message reference number (or message ID), and the expiration date of the message. The sender and destination identification information is, for example, a telephone number. The body includes user data, i.e., the message content (character string). Furthermore, information indicating that the data is being relayed by the relay app is added to the header or footer. This information includes information identifying the (original) sender of the message.

[0063] The relay application of the terminal device 10 records the transmitted message in a transmitted message database, which is stored in the storage unit 18 of the terminal device 10.

[0064] FIG. 8 is a diagram illustrating an example of a sent message database. In this example, the message database 2001 includes multiple records. Each record corresponds to one message. Each record includes a message ID, a sending time, a destination ID, a sender ID, a message body, a relay destination, and a message arrival confirmation. The message ID, destination ID, and sender ID are ID information representing a uniquely identifiable message, a destination, and a sender (sender), respectively, for each received message. The sending time indicates the time the message was sent, and the message body is the message content (character string) entered by the sender user. The relay destination indicates the terminal selected as the initial destination of the message. The message arrival confirmation is a flag indicating whether a message arrival confirmation has been received. Note that FIG. 8 simply illustrates accompanying information (such as the sending time, destination ID, and sender ID) of a message for the sake of explanation; however, the message data sent to the relay terminal is directly recorded in the message database 2001, and this accompanying information may be included in the header or footer of the message data.

[0065] The relay application of the terminal device 10 repeatedly retransmits the message until a retransmission stop condition for the message is satisfied. The retransmission stop condition is a condition determined by the relay application or a user, such as a condition that a message arrival confirmation has been received for the message.

[0066] When retransmitting a message, the relay application may exclude terminals that have already sent a message as a relay terminal in the message database 2001 when selecting other terminals to serve as relay terminals (step S105). If the priority of relay terminals is determined in descending order of signal strength, terminals ranked 1 to 5 in signal strength are selected as relay terminals. For the first retransmission, terminals ranked 6 to 10 in signal strength are selected as relay terminals. For the second retransmission, terminals ranked 11 to 15 in signal strength are selected as relay terminals. Signal strength generally correlates with distance, and it is believed that terminals with stronger signal strength tend to be closer and terminals with weaker signal strength tend to be farther away. In other words, this process generally corresponds to expanding the transmission range with each retransmission, such that the first time a message is transmitted, the message is transmitted to the nearest terminal, the first retransmission is transmitted to a terminal further away, and the second retransmission is transmitted to a terminal even further away.

[0067] Referring again to FIG. 7 , in step S107, the relay app of the terminal device 20 receives a message from the terminal device 10. Short-range wireless communication 91 between the relay apps is automatically established. Establishing short-range wireless communication 91 "automatically" means that communication is established without obtaining permission from the user each time. In this regard, the relay app may obtain permission from the user in advance (for example, when installing the relay app). The relay app of the terminal device 20 records the received message, i.e., the message to be relayed, in a database.

[0068] FIG. 9 is a diagram illustrating an example of a relay message database. In this example, the message database 2002 includes multiple records. Each record corresponds to one message. Each record includes a message ID, a destination ID, a sender ID, a message body, and a relay destination. The message ID, destination ID, and sender ID are ID information representing a uniquely identifiable message, destination, and sender (sender) for each received message. The message body is the content of the message entered by the sender user. The route information indicates the relay destination, which indicates the terminal selected as the next destination of the message. The relay app of the terminal device 20 can avoid duplication of messages received via short-range wireless communication 91 based on the message ID. Note that the message database 2002 does not necessarily need to record all received messages. If a message received from the terminal device 10 or another terminal is a duplicate of a previously received message (i.e., if it has the same message ID), the relay app may delete the received data without recording it in the message database 2002.

[0069] 2-3. Message Relay by Relay Terminal FIG. 10 is a sequence chart illustrating message relay processing by a relay terminal in the message relay system 1. Here, an example in which terminal device 20N relays a message is described. Although not specifically illustrated, the operation of each terminal device is basically performed by the processing of the relay app of each terminal. In step S201, the relay app of terminal device 20N receives a short-range wireless communication message from another device. Here, it can also be considered that the acquisition unit 11 of terminal device 20N has acquired the message from the other terminal. The received message is recorded in the message database 2002, as already explained.

[0070] In step S202, the relay application of terminal device 20N checks the destination of the received message. Specifically, the relay application references the destination ID included in the message and determines whether it matches the ID of its own terminal. If the received message is addressed to its own device, i.e., terminal device 20N, the relay application performs a receiving process (the receiving process will be described later).

[0071] In step S203, the relay app of the terminal device 20N checks whether it can connect to the public network 92 (similar processing to step S103). If connection to the public network 92 is possible, the relay app accesses the public network 92 and transmits a message. More specifically, the relay app transmits the message to a server (a so-called SMS center) that processes SMS messages. At this time, the relay app adds, to the header or footer of the message data, information indicating that the message is a message relayed by the relay app and identification information of the terminal (terminal device 20N in this example) that transmitted the message to the public network 92. The relay app transmits the message data with this information added to the SMS center. If the message has been transmitted via the public network 92, the relay app does not perform the processing described below. If connection to the public network 92 is impossible, the relay app proceeds to the next step.

[0072] In step S204, the relay application of the terminal device 20N identifies another terminal to be a relay terminal for the message. This process is performed in the same manner as in step S105. In step S205, the relay application transmits a message to the selected other terminal. This process is performed in the same manner as in step S106. That is, identification information of the terminal device 20N is added to the data (header or footer) of this message as information indicating the relay route (or forwarding route) of the message. Furthermore, the relay application adds identification information of the last cell of the terminal device 20N to the header or footer of the message. At this time, the relay application also adds a flag indicating the operating status of the last cell. The operating status of the last cell indicates whether the terminal device 20 was in a service area or out of service area when last checked. In step S206, the other terminal device 20 receives the message from the terminal device 20N. This process is performed in the same manner as in step S107.

[0073] The processes of steps S204 to S206 may be modified as appropriate. For example, in step S205, the relay application transmits the message after excluding the terminal device 10 that is the sender or the terminal device 20 that has been used for relaying at least once from the relay terminals. The terminal device 20N may execute various processes by referring to ID information or route information included in the message.

[0074] 2-4. Message Reception by Receiving Terminal If it is determined in step S202 that the message received via short-range wireless communication 91 is addressed to the terminal (terminal device 30), the relay app of the terminal device 30 performs a receiving process. Details of the receiving process will now be described.

[0075] 11 is a sequence chart illustrating a message reception process by a receiving terminal in the message relay system 1. In step S301, the relay application restores SMS message data from the received data. As described in step S106 or step S205, a header or footer indicating the message relay route is added to the relayed data. The relay application removes this header or footer to obtain data in the same format as the SMS message.

[0076] In step S302, the relay application passes the restored message data to the SMS application. The SMS application processes the passed message data in the same way as normal SMS message data. That is, the SMS application writes the message data to the corresponding storage area, notifies the user, and displays a message in response to a user operation (step S303).

[0077] The route through which the terminal device 30, which is the destination terminal, receives the message includes not only a route that ultimately receives the message via short-range wireless communication 91, but also a route that ultimately receives the message via a public network 92 (specifically, an SMS center and a base station) if the terminal device 30 is within the range of the public network 92. The processing of this route will be described. Consider an example in which a terminal device 20 (here, terminal device 20Z) that receives message data from another terminal device 20 is within the range of a base station that is functioning normally. In step S203, the relay app of terminal device 20Z determines that it can connect to the public network 92 and transmits the message data to the SMS center. The SMS center identifies the cell in which the destination terminal (terminal device 30 in this example) is within the range of the public network 92 and transmits the message data to the base station corresponding to that cell. The base station then transmits the message data to the terminal device 30, which is the destination terminal. From the perspective of the terminal device 30 receiving the message data from the base station, this is the same as a normal SMS message. In this case, the SMS app performs the same reception processing as a normal SMS message.

[0078] As described above, according to this embodiment, a terminal device 10 belonging to an out-of-service area can use short-range wireless communication 91 with other terminals to relay a message to a terminal device 20Z in an in-service area, and ultimately deliver the message to the destination terminal device 30.

[0079] 2-5. Processing on the Public Network If it is determined in step S103 or step S203 that connection to the public network 92 is possible, the message is sent to the public network 92 (more specifically, to the SMS center) and processed in the same way as a normal SMS message. Consider a situation where base stations near the current location of the destination terminal device 30 are not functioning properly due to a disaster or the like, and the terminal device 30 is out of range. In this case, even if the SMS center attempts to send a message to the terminal device 30 via the public network 92, the message cannot be sent because the terminal device 30 is out of range. In such a case, the public network 92 requests the terminal device 20 to relay the message.

[0080] FIG. 12 illustrates a relay process in a public network. In this example, the SMS center queries an HSS or the like to identify the final cell of the terminal device 30 (step S401). Furthermore, the SMS center identifies cells (hereinafter referred to as "neighboring cells") that are neighboring the final cell and whose base stations are functioning normally (step S402). In this example, the SMS center has access to a database that records base station information and identifies neighboring cells by referring to this database. The SMS center selects other terminal devices 20 located in the neighboring cells (step S403). The other terminal devices 20 located in the neighboring cells are identified by, for example, querying an HSS or the like. The SMS center queries the selected terminal devices 20 to see if they have the relay app installed. The SMS center records the identification information of terminal devices 20 that have responded that the relay app is installed. When the SMS center receives responses from a predetermined number of terminal devices 20 indicating that the relay app is installed, it requests these terminal devices 20 to relay the message (step S404). This message has the same format as the data sent to the other terminal in step S106 or step S205.

[0081] The terminal device 20 that receives this request from the SMS center relays the message to another device according to the message relay process described in Fig. 10. However, in this case, since the destination terminal, terminal device 30, is out of service, terminal device 20 does not transmit the message to the public network 92 even if it is within service area, but transmits the message to the other terminal device 20 via short-range wireless communication 91. In this case, the message data transmitted from the SMS center includes information indicating that the destination terminal, terminal device 30, is out of service area. The relay app refers to this information and selects the other terminal device 20 connected via short-range wireless communication 91, rather than the public network 92, as the direct destination of the message.

[0082] Note that the method for identifying other terminal devices 20 that are located in neighboring cells and have a relay app installed is not limited to this example. For example, the SMS center does not acquire location information about the terminal device 30, but instead requests a server (not shown) that manages message relaying to relay the message. In this case, the relay app in the terminal (terminal device 20 or terminal device 10) on which the relay app is installed periodically transmits its own location information to the server. The server manages the location information of each terminal device in a database. When requested to relay a message from the SMS center, the server identifies in the database neighboring cells for the terminal device 30's final cell and requests the terminal device 20 that is predicted from the database to be located in the neighboring cell to relay the message (i.e., transmits message data). The processing performed by the terminal device 20 that receives this request from the server is the same as when the SMS center requests relaying.

[0083] 2-6. Sending a Delivery Confirmation When a predetermined process is performed on the message data at the destination terminal, the relay app sends a delivery confirmation to the source terminal. The predetermined process is, for example, the transfer of the message data from the relay app to the SMS app, or the opening of the message in the SMS app. In this example, the message relay system 1 sends the delivery confirmation by reversing the route indicated by the route information added to the message data.

[0084] FIG. 13 is a diagram illustrating a message transmission path. In one example, a message M is delivered from a sender (terminal device 10) to a destination (terminal device 30) via a relay terminal (terminal device 20N) outside the service area and a relay terminal (terminal device 20Z) within the service area. At this time, each terminal adds route information when transmitting the message M. For example, when a message M is transmitted from the terminal device 10 to the terminal device 20N, the identification information of the terminal device 10 is added to the route information. The route information at this time is represented as route information R1. The terminal device 10 also adds the identification information of the final cell as the route information. A flag indicating the operation status of the corresponding base station is added to the identification information of the final cell. In the example of FIG. 13, the notation "(D)" indicates that the base station corresponding to that cell is not operating (i.e., out of service area). When a message M is transmitted from the terminal device 20N, the identification information of the terminal device 20N and the identification information of the final cell are added as route information. The route information at this time is represented as route information R2. When a message M is transmitted from terminal device 20Z, the identification information of terminal device 20Z and the identification information of the final cell are added as route information. The route information at this point is called route information R3. In this way, the transmission route is recorded in message M. This allows terminal device 30 to obtain information about the route (terminal via which) message M was transferred when it received it.

[0085] Returning to the explanation of the arrival confirmation, when the message arrives at the destination terminal device 30, the terminal device 30 performs the receiving process already described. After a predetermined process is performed on the message data, the relay application of the terminal device 30 performs the process of sending an arrival confirmation.

[0086] FIG. 14 is a diagram illustrating an example of an outline of the process for transmitting a delivery confirmation. In the message relay system 1, the delivery confirmation A follows the route shown in the figure and is transmitted from the destination (terminal device 30) to the sender (terminal device 10). Specifically, after a predetermined process is performed on the message data, the relay application of the terminal device 30 generates route information R31 by rearranging the route indicated by the route information R3 in reverse order. The relay application transmits the delivery confirmation A with the route information R31 added to it to the terminal indicated by the route information (terminal device 20Z in this example). Since the route information R31 indicates that terminal device 20Z is within the service area, the relay application of the terminal device 30 transmits the delivery confirmation to terminal device 20Z via the public network 92 (specifically, an SMS center).

[0087] The relay application of terminal device 20Z receives the arrival confirmation with route information R31 added. The relay application identifies the next terminal (terminal device 20N in this example) from route information R31, deletes the information about the next terminal from route information R31, and generates route information R32. The relay application transmits arrival confirmation A with route information R32 added to the terminal (terminal device 20N in this example) indicated by the route information. Because route information R32 indicates that terminal device 20N is out of range, the relay application transmits the arrival confirmation to terminal device 20N via short-range wireless communication 91.

[0088] The relay app of terminal device 20N receives the arrival confirmation with route information R32 added. The relay app identifies the next terminal (terminal device 10 in this example) from route information R32, deletes the information about the next terminal from route information R31, and generates route information R33. The relay app transmits arrival confirmation A with route information R33 added to the terminal (terminal device 10 in this example) indicated by the route information. Since route information R33 indicates that terminal device 10 is out of range, the relay app transmits the arrival confirmation to terminal device 10 via short-range wireless communication 91.

[0089] The relay application of the terminal device 10 receives the arrival confirmation with the route information R33 attached. The relay application determines from the route information R33 that the arrival confirmation is addressed to the terminal device 10. The relay application notifies the user of the arrival confirmation. The relay application also identifies the message for which the arrival confirmation is addressed from the message ID included in the arrival confirmation.

[0090] The relay application of the terminal device 10 that is the sender of the message continues to attempt to resend the message until it receives an arrival confirmation, at which point it stops resending the message.

[0091] As a result, the message relay system 1 can notify the sender of the arrival confirmation by tracing the reverse route of the route along which the message M was delivered.

[0092] 3. Modifications The present invention is not limited to the above-described embodiment, and various modifications are possible. Some modifications will be described below. Two or more of the following features may be combined and applied.

[0093] (1) Message Relay System 1 The hardware configuration and network configuration of the message relay system 1 are not limited to those exemplified in the embodiment. The message relay system 1 may have any hardware configuration and network configuration as long as the required functions can be realized. For example, multiple physical devices may cooperate to function as the message relay system 1. For example, the message relay system 1 may include various networks such as a short-range wireless communication 91 or a public network 92. The message relay system 1 may also include various base stations. In this case, the terminal device 20Z connected to the base station 82 in an in-service area may obtain, from the base station, information on the presence of the terminal to which the message is addressed. This allows the terminal device 20Z to obtain information on the base station to which the terminal device 30 was last connected, even when the terminal device 30 is in an out-of-service area.

[0094] The message relay system 1 relays messages only when a predefined activation condition is met, and does not need to transfer messages when the activation condition is not met. For example, this activation condition may be the occurrence of a disaster such as an earthquake. In this case, the message relay system 1 does not relay messages under normal circumstances (when no earthquake has occurred). In this case, each terminal outside the service area receives information that an earthquake has occurred (i.e., the activation condition has been met) via a route other than the public network 92. According to this example, messages are not relayed in a situation where, for example, a terminal device simply malfunctions and is unable to communicate with the base station (when no earthquake has occurred).

[0095] (2) Terminal Device 10, Terminal Device 20, Terminal Device 30 The correspondence between the functional elements of the terminal device 10 and the hardware is not limited to that exemplified in the embodiment. For example, in the embodiment, at least some of the functions described as being implemented in the terminal device 10 may be implemented in another device or system, and conversely, at least some of the functions described as being implemented in another device or system may be implemented in the terminal device 10. The same applies to the terminal device 20 or the terminal device 30.

[0096] (3) Software Configuration The software configuration of the terminal device 10, the terminal device 20, or the terminal device 30 is not limited to the example described in the embodiment. For example, in the embodiment, an example has been described in which a general-purpose SMS app performs processing in cooperation with a relay app dedicated to the message relay system 1. However, the relay app may perform processing related to sending and receiving SMS messages. In other words, the relay app may be capable of sending, relaying, and receiving SMS messages independently of the general-purpose SMS app.

[0097] (4) Message Transmission Method at the Transmitting Terminal The sequence chart shown in FIG. 7 merely illustrates an example of the operation, and the message transmission method at the transmitting terminal is not limited thereto. Some of the illustrated operations may be changed or omitted, the order may be changed, or new operations may be added. For example, even if the terminal device 10 is able to connect to the public network 92, it may request another terminal to relay a message. Furthermore, although the embodiment has been described as an example in which the relay app of the terminal device 10 repeatedly retransmits the message until it receives a confirmation of arrival, the message retransmission may be omitted. Alternatively, the message retransmission may be repeated for a certain period of time regardless of the confirmation of arrival. Furthermore, the priority used when selecting another terminal in step S105 may take into account other information, such as the type of device or the frequency of use of the terminal, instead of or in addition to radio wave strength.

[0098] (5) Message Relay Method at the Relay Terminal The sequence chart shown in FIG. 10 merely illustrates one example of the operation, and the message relay method at the relay terminal is not limited to this. Some of the illustrated operations may be changed or omitted, the order may be changed, or new operations may be added. If the connection of the terminal device 20N to the public network 92 is restored in step S203, the relay app may send a direct message to the terminal device 30 at the time of restoration. In this case, the terminal device 20N may store the message in the message database 2001 for a predetermined time (e.g., one hour or more). Furthermore, if short-range wireless communication is established with the terminal device 30, which is the destination terminal, the terminal device 20 may notify other terminals that a direct message has been sent to the terminal device 30.

[0099] (6) Method for Sending Arrival Confirmation The method for sending arrival confirmation is not limited to the example described in the embodiment. The transmission route of the arrival confirmation is not limited to the reverse of the message transmission route, and may be a route that passes through a terminal not included in the message transmission route. For example, as described in Section 2-6, the relay app of the terminal device 30 specifies a route obtained by rearranging the message transmission route in reverse order as the transmission route of the arrival confirmation. However, it is conceivable that another terminal (e.g., terminal device 20N) that was near a certain terminal (e.g., terminal device 20Z) when the message was sent moves out of the communication range of the short-range wireless communication 91, and therefore, even if the terminal device 20Z attempts to send an arrival confirmation to the terminal device 20N, the short-range wireless communication 91 cannot be established. In such a case, the relay app of the terminal device 20Z may search for a terminal not included in the route information that can establish the short-range wireless communication 91, and send the arrival confirmation to that terminal. Alternatively, the relay app of the terminal device 30 may initially specify only the destination without specifying route information, and transmit the arrival confirmation to the public network 92 or another nearby terminal. In this case, the message arrival confirmation is relayed in the same manner as the message. Alternatively, the message relay system 1 may omit sending the message arrival confirmation depending on the application specifications or user instructions. In these cases, since adding route information to the message is of little technical significance, the relay application of the relay terminal does not need to add the identification information of the relay terminal.

[0100] (7) Method of Collecting Location Information The sequence chart shown in FIG. 6 merely shows an example of the operation, and the method of collecting location information is not limited to this. Some of the illustrated operations may be changed or omitted, the order may be changed, or new operations may be added. For example, the relay app of the terminal device 10 or the terminal device 20 may obtain terminal information of other terminals in the same cell as the terminal device 10 or the terminal device 20 from the public network 92 (e.g., a base station or core network of a mobile network).

[0101] (8) Database The databases (or the data itself) of the message relay system 1 shown in Figures 5, 8, and 9 are not limited to those exemplified in the embodiments. In this example, any data may be registered in the database. For example, the data recorded in the base station database 1001 may be coordinate information of a base station or terminal for each timestamp. The timestamps may be recorded at any interval. The route information recorded in the message database 2002 may include information indicating the time at which a message was relayed by each terminal.

[0102] (9) Messages The messages are not limited to those exemplified in the embodiments. The messages may be in any form as long as the recipient is specified. For example, the messages may include images, videos, or audio instead of or in addition to text. The configurations or operations described in the embodiments may be modified as appropriate depending on the type of message. Furthermore, the messages are not limited to so-called SMS messages. The messages may have a unique data structure used in a specific application program, for example. The public network 92 is determined depending on the data structure of the message. For example, in the case of an SMS message, the public network 92 is a mobile network, and in the case of a unique message used in a messaging app, the public network 92 is the Internet.

[0103] (10) Others The various programs executed by the processor 101 may be provided by downloading via a network such as the Internet, or may be provided in a state recorded on a computer-readable non-transitory recording medium such as a DVD-ROM. Each processor may be, for example, a CPU, an MPU (Micro Processing Unit), or a GPU (Graphics Processing Unit).

[0104] The block diagrams used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of hardware and / or software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are directly or indirectly connected (e.g., wired, wireless, etc.) and these multiple devices. The functional block may also be realized by combining software with the single device or multiple devices.

[0105] Functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs transmission is called a transmitting unit or transmitter. As mentioned above, there are no particular limitations on how these functions are implemented.

[0106] For example, the terminal device 10 according to an embodiment of the present disclosure may function as a computer that performs the processing of the present disclosure.

[0107] Each aspect / embodiment described in the present disclosure may be applied to at least one of systems using LTE (Long Term Evolution), LTE-Advanced (LTE-A), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system), FRA (Future Radio Access), NR (New Radio), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, UWB (Ultra-Wideband), Bluetooth (registered trademark), or other suitable systems, and next-generation systems enhanced based on these. Furthermore, a combination of multiple systems (e.g., a combination of at least one of LTE and LTE-A with 5G) may also be applied.

[0108] The order of the procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this disclosure may be changed unless it is consistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the particular order presented.

[0109] Input and output information may be stored in a specific location (for example, memory) or may be managed using a management table. Input and output information may be overwritten, updated, or added to. Output information may be deleted. Input information may be sent to another device.

[0110] The determination may be made based on a value represented by one bit (0 or 1), a Boolean value (true or false), or a numerical comparison (e.g., comparison with a predetermined value).

[0111] Although the present disclosure has been described in detail above, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described herein. The present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the present disclosure as defined by the claims. Therefore, the description of the present disclosure is intended to be illustrative and does not have any limiting meaning on the present disclosure.

[0112] Software, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise, should be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc. Additionally, software, instructions, information, etc. may be transmitted or received over a transmission medium. For example, if software is transmitted from a website, server, or other remote source using wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave), then such wired and / or wireless technologies are included within the definition of a transmission medium.

[0113] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof. Note that terms described in this disclosure and terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings.

[0114] Furthermore, the information, parameters, etc. described in this disclosure may be expressed using absolute values, may be expressed using relative values ​​from a predetermined value, or may be expressed using other corresponding information.

[0115] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0116] As used in this disclosure, any reference to an element using a designation such as "first," "second," etc. does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed or that the first element must in some way precede the second element.

[0117] The "unit" in the configuration of each of the above devices may be replaced with "means," "circuit," "device," or the like.

[0118] When the terms "include," "including," and variations thereof are used in this disclosure, these terms are intended to be inclusive, similar to the term "comprising." Furthermore, when the term "or" is used in this disclosure, it is not intended to be an exclusive or.

[0119] In this disclosure, where articles are added by translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0120] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."

[0121] 1...Message relay system, 10...Terminal device, 1001...Base station database, 101...Processor, 102...Memory, 103...Storage, 104...Communication device, 105...Input device, 106...Display device, 11...Acquisition unit, 12...Collection unit, 13...First transmission unit, 14...First reception unit, 15...Acceptance unit, 18...Storage unit, 19...Control unit, 20...Terminal device, 2001...Message database, 20...Terminal device, 21...Second reception unit, 22...First determination unit, 23...Second transmission unit, 24...Addition unit, 30...Terminal device, 31...Second determination unit, 32...Reception processing unit, 81, 82...Base station, 91...Short-range wireless communication, 92...Public network, A...Delivery confirmation, M...Message, R1, R2, R3, R31, R32, R33...Route information

Claims

1. A terminal device having an acquisition unit that acquires a first message addressed to a party designated as a destination; a collection unit that collects information on one or more other terminals within a range where short-range wireless communication is possible; and a first transmission unit that transmits the first message from the one or more other terminals to a first terminal selected based on the information via the short-range wireless communication.

2. A terminal device as described in claim 1, further comprising a first receiving unit that receives a confirmation of arrival from one of the one or more other terminals indicating that the first message has reached the destination, and if the confirmation of arrival is not received, the first transmitting unit transmits the first message to a second terminal other than the first terminal among the one or more other terminals.

3. The terminal device according to claim 1, wherein the one or more other terminals are mobile communication terminals, and the information about the other terminals includes in-service information about base stations with which the other terminals are communicating.

4. A terminal device as described in claim 1, comprising: a second receiving unit that receives a second message with a specified destination from the one or more other terminals via the short-range wireless communication; a first determining unit in the terminal that determines whether or not the terminal can connect to a public network; and a second transmitting unit that transmits the second message via the public network if the terminal can connect to the public network.

5. The terminal device according to claim 4, wherein, when the terminal device is unable to connect to the public network, the second transmitting unit transmits the second message via the short-range wireless communication to a third terminal selected from the one or more other terminals based on the information.

6. The terminal device according to claim 4, further comprising an adding unit that adds identification information of the device to the second message, and the second transmitting unit transmits the second message to which the identification information has been added by the adding unit.

7. A terminal device according to claim 4, comprising: a second determination unit that determines whether the second message is addressed to the device itself; and a reception processing unit that performs reception processing of the second message when it is determined that the second message is addressed to the device itself.

8. The terminal device according to claim 7, wherein the second message includes route information indicating the route of the terminal device that relayed the second message, and the receiving processing unit includes processing for sending an arrival confirmation indicating that the second message has reached the sender of the second message, so as to trace back the route indicated by the route information included in the second message.

9. A message sending method comprising the steps of: acquiring a first message for a party designated as a destination; collecting information on one or more other terminals within a range where short-range wireless communication is possible; and sending the first message from the one or more other terminals to a first terminal selected based on the information via the short-range wireless communication.

Images