JP4179923B2 - Message transmission system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a message transmission system, and more particularly to a message transmission system that transmits a message by wireless communication.
[0002]
[Prior art]
Due to the rapidly developing mobile communication technology in recent years, mobile phones such as mobile phones, PDAs (Personal Digital Assistants), small personal computers, etc. have become widespread, and each person has one or more devices. In mobile terminals, a rechargeable battery is generally used as a power source in order to enable free portability, and network access is generally performed wirelessly. For this reason, it is possible to construct a serverless network between mobile terminals, and communication is performed by each person.
[0003]
In such a serverless network, it is effective to use short-range wireless (Bluetooth) in terms of mobility and power consumption. When sharing information on a serverless network using Bluetooth, it is necessary to transmit a message from a caller to everyone.
[0004]
In this case, as one of conventional message transmission methods, there is a method of transmitting a message from a certain terminal to all connectable terminals. The terminal that has received the message transfers the message to all the terminals that can be connected from the terminal, so that all the connected terminals receive the message.
[0005]
FIG. 10 is a diagram showing a conventional message transmission method.
[S101] Caller terminal A transmits a message to be transmitted to connectable terminals B and C.
[S102] Terminal B connects to terminals D and E and transmits the message received from caller A.
[S103] The terminal C is connected to the terminals B, E, and F and transmits the message received from the caller A. At this time, the terminals B and E are notified that the message has already been received.
[S104] The terminal E transmits the received message to the terminals D and G. At this time, a terminal message is returned from the terminal D. Note that the terminal E receives the message from the terminal B, and notifies the terminals C and F of the achieved message when connected.
[S105] The terminal F transmits the message received from the terminal C to the terminals E and G, but receives the received message from both terminals. In this way, the message is transmitted to the terminals A to G. The total number of transmissions / receptions at this time is 11 times.
[0006]
In addition, as a conventional message transmission method, there is a method in which data is individually transmitted in order one by one to a terminal to which a message is to be transmitted. When data is transmitted from a caller terminal to a terminal that cannot be directly connected, the message is relayed to another terminal.
[0007]
FIG. 11 shows a conventional message transmission method.
[S111] The caller A sends a message to the terminal B and obtains information that the terminal B can connect to the terminal D at the same time.
[S112] Caller A sends a message to terminal B with data instructed to transfer to terminal D. Terminal B transmits the received message to terminal D as instructed.
[S113] The caller A sends a message to the terminal C, and obtains information that the terminal C can connect to the terminal E at the same time.
[S114] Caller A sends a message to terminal C with data instructed to transfer to terminal E. Terminal C transmits the received message to terminal E as instructed.
[S115] The caller A transmits a message to the terminal F, and obtains information that the terminal F can connect to the terminal G at the same time.
[S116] Caller A sends a message to terminal F with data instructed to transfer to terminal G. Terminal F transmits the received message to terminal G as instructed. In this way, the message is transmitted to the terminals A to G. The total number of transmissions / receptions at this time is 12.
[0008]
Furthermore, as a conventional message transmission technique, a message is transmitted from a server to a communication terminal, the communication terminal transmits a message to another communication terminal using short-range wireless communication, and an inquiry is made from another communication terminal. A technique of responding when a request is received has been proposed (for example, Patent Document 1).
[0009]
[Patent Document 1]
JP 2002-164840 A (paragraph numbers [0028] to [0031], FIG. 1)
[0010]
[Problems to be solved by the invention]
However, in the conventional technique as described above (Japanese Patent Laid-Open No. 2002-164840), the burden on the communication terminal on the transmission side that receives a message from the server and performs transmission / reception with a plurality of terminals is large, and an optimum transmission route is also considered. Therefore, there was a problem that message transmission could not be performed efficiently.
[0011]
Further, in the conventional message transmission technique shown in FIG. 10, since one terminal receives the same message from a plurality of terminals or indicates that it has already received a message, the number of communication processes is There is a problem in that the more crowded each other, the greater the power consumption associated with message transmission / reception. Furthermore, although it is essential to know the transmission status for accurate communication, there has been a problem that the sender cannot know whether or not the transmission has been performed to all the parties who want to transmit the message.
[0012]
On the other hand, the conventional message transmission technique shown in FIG. 11 has a problem that the caller needs to repeat transmission / reception as many times as the number of other parties to be transmitted, and the load on the caller increases as the number of terminals to be transmitted increases. It was.
[0013]
The present invention has been made in view of these points, and an object of the present invention is to provide a message transmission system that efficiently transmits message information and improves communication quality and service quality.
[0014]
[Means for Solving the Problems]
In the present invention, in order to solve the above-mentioned problem, in the message transmission system 1 that transmits a message by wireless communication as shown in FIG. 1, a connection information holding unit 11 that holds connection information about the interconnection state between terminals, In order to describe new connection information in the forwarding destination terminal including the forwarding route and the forwarding route calculation unit 12a that calculates the forwarding route passing through all the terminals with the own terminal as the starting point and the ending point based on the connection information When a message is received, a source message transmission unit 13a configured to add the connection information table of the message to the message and transmit the message, and describe the connection information about the own terminal in the connection information table, And forwarding terminals 10b-1 to 10b-n including a data transmission / reception unit 13b for transmitting a message to the next forwarding destination terminal. A message transmission system 1, are provided.
[0015]
Here, the connection information holding unit 11 holds connection information related to an interconnection state between terminals. Based on the connection information, the forwarding route calculation unit 12a calculates a forwarding route that goes through all the terminals, with its own terminal as the start point and the end point. The transmission source message transmission unit 13a adds a connection information table for describing new connection information in the forward destination terminal, including the forwarding route, and transmits the message. When the data transmitting / receiving unit 13b receives the message, the data transmitting / receiving unit 13b describes the connection information about the terminal itself in the connection information table, and transmits the message to the next forwarding destination terminal.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a principle diagram of a message transmission system according to the present invention. The message transmission system 1 does not have a server and transmits the same message between terminals on a network composed of a plurality of terminals (mobile terminals) connected to each other by radio waves having a finite reach. System.
[0017]
The message transmission system 1 includes a transmission source terminal 10a that transmits a message, and forwarding terminals 10b-1 to 10b-n that relay and forward the message of the transmission source. In order to make the explanation easy to understand, the terminal is classified as a transmission source terminal / forwarding terminal, but in reality, both functions are installed in one terminal (message transmission device).
[0018]
For the source terminal 10a, the connection information holding unit 11 holds connection information related to the mutual connection state between the terminals. Based on the connection information, the forwarding route calculation unit 12a calculates a forwarding route that goes through all the terminals, with its own terminal as the start point and the end point. The transmission source message transmission unit 13a adds a connection information table for describing new connection information in the forward destination terminal, including the forwarding route, and transmits the message.
[0019]
When the data transmission / reception unit 13b receives a message for the forwarding terminals 10b-1 to 10b-n, the connection information regarding the terminal itself is described in the connection information table, and the message is transmitted to the next forwarding destination terminal. Further, the data transmitting / receiving unit 13b of the forwarding terminal at the end of the forwarding route generates and transmits receipt certification data indicating completion of message forwarding. A connection information table is also added to this receipt certificate data.
[0020]
The forwarding route recalculation unit 12b recalculates a new forwarding route for an unforwarded terminal based on the connection information when the message cannot be transmitted to the terminal designated as the forwarding route.
[0021]
FIG. 2 is a diagram showing the configuration of the message transmission device. The message transmission device (terminal) 10 includes a connection information holding unit 11, a forwarding route determination unit 12, a data communication unit 13, a message generation unit 14-1, and a message presentation unit 14-2.
[0022]
The forwarding route determination unit 12 includes the forwarding route calculation unit 12a and the forwarding route recalculation unit 12b, and the data communication unit 13 includes the transmission source message transmission unit 13a and the data transmission / reception unit 13b. The message generator 14-1 generates a message based on a user instruction. The message presentation unit 14-2 presents the received message to the user.
[0023]
Next, the connection information holding unit 11 and the connection information table will be described. FIG. 3 is a diagram showing connection information held by the connection information holding unit 11. The connection information 11-1 is information indicating the interconnection state of the transmission source terminal 10a and the forwarding terminals 10b-1 to 10b-n, and the link strength value is described as the interconnection state for each terminal name (or unique ID). Is done.
[0024]
For example, if the link strength between the terminal A and the terminal B is 10, the strength value 10 is written at the position of the terminal AB. The larger the link strength value, the better the connection state, and communication is possible with less power consumption (if the link strength value is 0, it indicates that the terminals are not connected).
[0025]
FIG. 4 is a diagram showing a connection information table. The connection information table T is transmitted in addition to the message or the receipt certification data, and the terminal that has received the message or the receipt certification data stores the current connection state between the own terminal and the other terminal in the connection information table T ( Enter the link strength value.
[0026]
Also, the completed connection information table T is added again to the message or the receipt proof data and transmitted to the next destination together with the message. In the connection information table T shown in the figure, a forwarding route (forwarding order) is also added, and the terminal A is the transmission source, and messages are transmitted in the order of A → B → C →. It is shown.
[0027]
Next, the operation of the system of the present invention will be described in detail. In explaining the operation, the processing of each terminal is classified into three types: message transmission processing, message transfer processing, and receipt certificate data transfer processing. The message transmission process is a process of actively transmitting a message by selecting a terminal to be sent by one terminal as a message source. The message transfer process is a process for passively receiving a message from a connected terminal, confirming the message, and transmitting it to the next forwarding destination. The receipt certificate data transfer process is a process of passively receiving receipt certificate data from a connected terminal and transmitting it to the next forwarding destination.
[0028]
FIG. 5 is a flowchart showing the operation of the message transmission process.
[S1] The source terminal 10a creates a message to be transmitted according to a user instruction.
[S2] The source terminal 10a confirms the connection state of the terminal group that is the target of message forwarding from the connection information between the terminals held in the terminal itself.
[S3] As a result of step S2, if the connection state of all terminals to be forwarded is known, the process proceeds to step S4, and if an unknown terminal exists, the process proceeds to step S5.
[S4] The forwarding route calculation unit 12a calculates a forwarding route that returns from the terminal to the terminal through all the forwarding destination terminals. Go to step S7.
[S5] The forwarding route calculation unit 12a calculates a forwarding route that returns from the terminal to the terminal via a forwarding destination terminal whose connection state is known, and determines the forwarding order.
[S6] The forwarding route calculation unit 12a places the forwarding destination terminal whose connection state is unknown after the last terminal in the forwarding order determined in step S5 (arranges in a random order when there are a plurality).
[S7] The source message transmitter 13a creates a connection information table T for assigning numbers in the determined forwarding order and for entering the forwarding destination terminal names and their connection states.
[S8] The sender message transmitter 13a enters the connection information of the sender terminal 10a in the connection information table T created in step S7.
[S9] The connection information table T generated in step S8 is added to the message generated in step S1 to obtain a forward message.
[S10] The source message transmitter 13a transmits the forward message generated in step S9 to the next destination terminal.
[0029]
When obtaining a forwarding route, a message is transmitted from the transmission source terminal 10a and a transmission route that minimizes the number of transmissions / receptions until the receipt certificate data is returned is determined, or a message is transmitted from the transmission source terminal 10a. During the processing procedure until the receipt proof data is returned, the forwarding route is determined by obtaining the forwarding route that minimizes the total amount of power.
[0030]
6 and 7 are flowcharts showing the operation of the message transfer process.
[S21] The data transmitting / receiving unit 13b of the forwarding terminal 10b receives a message from the connected terminal.
[S22] The data transmitting / receiving unit 13b extracts the message from the received message, and the message presenting unit 14-2 presents the message to the user.
[S23] The data transmission / reception unit 13b reads the connection information table T added to the received message, sets this as a new connection state, and updates the information held in the terminal itself.
[S24] The data transmitter / receiver 13b confirms the current connection state of the terminal itself.
[S25] The data transmitting / receiving unit 13b writes the information obtained in step S24 as new information in the connection information table T added to the message, and updates the table.
[S26] The data transmitter / receiver 13b confirms the next forwarding destination terminal based on the forwarding order information (forwarding route) obtained from the message.
[S27] The data transmitter / receiver 13b determines whether all the terminals designated as the forwarding destination at the present time have already entered the connection information, that is, whether or not the message has been received. If the message has been received (if it is the last recipient), go to step S35, and if there is an unreceived terminal, go to step S28.
[S28] The data transmitter / receiver 13b determines whether or not the next forwarding destination terminal is included in the connectable terminals confirmed in step S24. If it is included, go to step S37, otherwise go to step S29.
[S29] The data transmitting / receiving unit 13b determines whether there is a terminal that matches the connectable terminal confirmed in step S24 among the unreceived terminals. If it exists, go to step S30, otherwise go to step S32.
[S30] The data transmitting / receiving unit 13b determines, as a next forwarding destination, a terminal having the smallest designated forwarding order number among terminals that have not been received in step S29 and are determined to be connectable to the terminal itself. .
[S31] The data transmitting / receiving unit 13b rewrites the forwarding order number in the connection information table T, and assigns a new forwarding order (next number of the terminal itself) to the next forwarding destination terminal determined in step S30. Go to step S37.
[S32] If the data transmission / reception unit 13b can confirm from the recognized connection information that there is a forwarding route to an unreceived terminal, the process proceeds to step S33. If no forwarding route to all unreceived terminals exists, Those terminals are determined to have been disconnected from the network, and the process proceeds to step S35.
[S33] The forward route recalculation unit 12b calculates the forward route from the own terminal through the terminal to the caller for those that have the forward route among unreceived terminals.
[S34] The data transmitting / receiving unit 13b performs a new forwarding order designation by rewriting the forwarding order information in the connection information table T in order to reflect the forwarding route determined in step S33. Go to step S37.
[S35] The data transmitting / receiving unit 13b sets the data indicating that all the new connection information tables T updated in step S25 have been received as reception certification data. Note that only the connection information added to the message may be returned and used as receipt certification data.
[S36] The data transmission / reception unit 13b transmits the receipt certification data generated in step S35 to the designated forwarding destination terminal and terminates.
[S37] The data transmitting / receiving unit 13b adds the updated connection information table T to the message again.
[S38] The data transmitter / receiver 13b transmits the message generated in step S37 to the terminal designated as the next destination.
[0031]
8 and 9 are flowcharts showing the operation of the receipt certificate data transfer process.
[S41] The data transmitter / receiver 13b receives the receipt proof data from the connected terminal.
[S42] The data transmission / reception unit 13b reads the connection information table T added to the received receipt certification data, and updates the connection information of the other terminals held in the own terminal as new information.
[S43] The data transmitting / receiving unit 13b confirms the current connection state of the terminal itself.
[S44] The connection information table T added to the receipt proof data as the new information obtained in step S43 is updated.
[S45] The data transmitting / receiving unit 13b confirms the next forwarding destination terminal based on the forwarding order information obtained from the receipt certification data.
[S46] The data transmitting / receiving unit 13b proceeds to step S51 if the next forwarding destination terminal is included in the connectable terminals confirmed in step S43, and proceeds to step S47 otherwise.
[S47] If the data transmission / reception unit 13b confirms from the recognized connection information that there is a forwarding route to the source terminal 10a, the process proceeds to step S49. If there is no forwarding route to the source terminal 10a, It is determined that the source terminal 10a or the route to it is disconnected from the network, and the process goes to step S48.
[S48] The data transmitter / receiver 13b discards the receipt proof data and ends.
[S49] The forwarding route recalculation unit 12b calculates a forwarding route from the own terminal through the known terminal to the caller and determines the route.
[S50] The data transmitter / receiver 13b designates a new forwarding order by rewriting the forwarding order information in the connection information table T in order to reflect the forwarding route determined in step S49.
[S51] The data transmitting / receiving unit 13b adds the updated connection information table T to the receipt certification data again.
[S52] The data transmitting / receiving unit 13b transmits the receipt certification data generated in step S51 to the terminal designated as the next destination. However, when the transmission source terminal 10a receives the receipt proof data, Step S41 and Step S42 are executed, and the process ends.
[0032]
Of the above process steps, the process of designating the forwarding order is a process of assigning numbers in the order of forwarding in the connection information table T of FIG. If the same terminal has to be passed twice due to the connection form, a plurality of numbers may be assigned.
[0033]
In addition, regarding the calculation of the forwarding route, an existing calculation method (a calculation method already adopted in a navigation system or the like) such as a solution method of the traveling salesman problem is used. When this calculation is performed, the usage cost between the terminals is required. However, when it is desired to reduce the number of transmissions and receptions, 0 is used if the connection between the terminals is possible, and 1 is used if the connection is impossible. Calculate the route with the lowest cost.
[0034]
Further, when it is desired to reduce the power consumption, it is necessary to pass through a portion with a high link strength. Therefore, the reciprocal of the link strength is used as a cost between terminals, and a route is calculated so as to minimize the traveling cost.
[0035]
As described above, in the present invention, in a serverless network environment, a message is transmitted through an appropriate forwarding route that is initially determined by calculation. The effect of reducing the total power consumption associated with transmission / reception increases. Further, it is possible to solve the problem that a large burden is applied only to a single terminal. Furthermore, the receipt of the receipt is forwarded so that the current state of the network can be known, and more accurate communication can be performed.
[0036]
(Supplementary note 1) In a message transmission system for transmitting a message by wireless communication,
A connection information holding unit that holds connection information related to the state of mutual connection between terminals, a forwarding route calculation unit that calculates a forwarding route passing through all terminals with the terminal as a starting point and an end point based on the connection information, A source terminal that includes a route, and that includes a source message transmission unit that transmits a connection information table for describing new connection information in a forward destination terminal to a message, and
When the message is received, the connection information regarding the own terminal is described in the connection information table, and the forwarding terminal including a data transmission / reception unit that transmits the message to the next forwarding destination terminal;
A message transmission system comprising:
[0037]
(Additional remark 2) The said data transmission / reception part of the said forward terminal used as the last of the forward route produces | generates the receipt certification data which shows the completion of the forwarding of a message which added the connection information table, and transmits. The message transmission system described.
[0038]
(Additional remark 3) When the said data transmission / reception part receives receipt certification data and recognizes that the forwarding route to the said transmission origin terminal does not exist from connection information, it discards receipt certification data, It is characterized by the above-mentioned. The message transmission system according to attachment 2.
[0039]
(Additional remark 4) When the said data transmission / reception part receives a message and receipt certification data, it describes and updates new connection information in the said connection information table, The message and receipt certification data are transmitted. 2. The message transmission system according to 2.
[0040]
(Additional remark 5) When the said forwarding terminal cannot transmit a message to the terminal designated as the forwarding route, the forwarding route which recalculates the new forwarding route with respect to the unforwarded terminal based on connection information The message transmission system according to claim 1, further comprising a recalculation unit, wherein the data transmission / reception unit transmits a message in which an old forwarding route is replaced with a new forwarding route.
[0041]
(Additional remark 6) The said forwarding route calculation part calculates | requires the forwarding route from which the frequency | count of transmission / reception until the receipt certification data returns by transmitting a message from the said transmission origin terminal, and the said forwarding route recalculation part is said forwarding 6. The message transmission system according to appendix 5, wherein a message is transmitted from a terminal and a forwarding route that minimizes the number of times of transmission / reception until the receipt proof data is transmitted to the source terminal is obtained.
[0042]
(Additional remark 7) The said forwarding route calculation part calculates | requires the forwarding route from which the total amount of electric power becomes the smallest during the processing procedure after transmitting a message from the said transmission origin terminal, and returning receipt certification data, The calculation unit transmits a message from the forwarding terminal and obtains a forwarding route in which the total amount of electric power is the smallest during the processing procedure until the receipt proof data is transmitted to the source terminal. 5. The message transmission system according to 5.
[0043]
(Supplementary Note 8) In a message transmission device that transmits a message by wireless communication,
A connection information holding unit for holding connection information related to the mutual connection state between terminals;
When the local terminal is the source terminal, the forward route is calculated based on the connection information, with the local terminal serving as the start and end points and passing through all terminals. A forwarding route determination unit that recalculates a new forwarding route for an unforwarded terminal based on the connection information when a message cannot be sent to the terminal that is
If the local terminal is the source terminal, it sends the connection information table that includes the forward route and describes new connection information at the forward destination terminal to the message. If the local terminal is the forward terminal, Describe connection information about the terminal in the connection information table, and send a message to the next forwarding destination terminal. If the terminal is at the end of the forwarding route, it generates receipt certification data indicating the completion of forwarding the message. A data communication unit to transmit
A message transmission device comprising:
[0044]
(Supplementary Note 9) In a message transmission method for transmitting a message by wireless communication,
When a message is transmitted from the source terminal to other multiple forwarding terminals in the same network, the source terminal calculates the forwarding route by using connection information regarding the mutual connection status between the forwarding terminals currently known. Decide
The source terminal adds a forwarding route and a connection information table for describing new connection information of each forwarding terminal to the message, and transmits it to the next forwarding terminal.
The forwarding terminal that received the message fills its connection information in the connection information table attached to the message and sends it to the next forwarding terminal,
The terminal at the end of the forwarding route generates and sends receipt data indicating that the message forwarding is complete,
If the message cannot be sent to the terminal specified as the forwarding route, the message is transmitted to all the forwarding terminals by recalculating the new forwarding route for the unforwarded terminal based on the connection information. A message transmission method characterized by the above.
[0045]
【The invention's effect】
As described above, in the message transmission system of the present invention, the source terminal calculates the forwarding route that passes through all the terminals with the own terminal as the starting point and the ending point based on the connection information regarding the interconnection state between the terminals. Then, a connection information table including the forwarding route and describing new connection information at the forwarding destination terminal is added to the message and transmitted. When the message is received, the forwarding terminal describes the connection information about the terminal itself in the connection information table and transmits the message to the next forwarding destination terminal. As a result, messages can be transmitted efficiently, and communication quality and service quality can be improved.
[Brief description of the drawings]
FIG. 1 is a principle diagram of a message transmission system according to the present invention.
FIG. 2 is a diagram illustrating a configuration of a message transmission device.
FIG. 3 is a diagram illustrating connection information held by a connection information holding unit.
FIG. 4 is a diagram showing a connection information table.
FIG. 5 is a flowchart showing an operation of message transmission processing;
FIG. 6 is a flowchart showing an operation of message transfer processing.
FIG. 7 is a flowchart showing an operation of message transfer processing.
FIG. 8 is a flowchart showing an operation of a receipt certificate data transfer process.
FIG. 9 is a flowchart showing an operation of a receipt certificate data transfer process.
FIG. 10 is a diagram illustrating a conventional message transmission method.
FIG. 11 is a diagram illustrating a conventional message transmission method.
[Explanation of symbols]
1 Message transmission system
10a Source terminal
10b-1 to 10b-n Forwarding terminal
11 Connection information holding unit
12a Forwarding route calculation part
12b Forward route recalculation part
13a Source message transmitter
13b Data transceiver

Claims (5)

In a message transmission system that transmits messages by wireless communication,
A connection information holding unit that holds connection information related to the state of mutual connection between terminals, a forwarding route calculation unit that calculates a forwarding route passing through all terminals with the terminal as a starting point and an end point based on the connection information, A source terminal that includes a route, and that includes a source message transmission unit that transmits a connection information table for describing new connection information in a forward destination terminal to a message, and
When the message is received, the connection information regarding the own terminal is described in the connection information table, and the forwarding terminal including a data transmission / reception unit that transmits the message to the next forwarding destination terminal;
A message transmission system comprising: 2. The message according to claim 1, wherein the data transmission / reception unit of the forwarding terminal at the end of the forwarding route generates and transmits receipt proof data indicating completion of forwarding of the message, to which a connection information table is added. Transmission system. 3. The data transmission / reception unit receives the certification data and discards the certification data when recognizing that there is no forwarding route from the connection information to the source terminal. Message transmission system. When the forward terminal cannot transmit a message to the terminal designated as the forward route, the forward terminal recalculates a new forward route for the unforwarded terminal based on the connection information. The message transmission system according to claim 1, wherein the data transmission / reception unit transmits a message in which an old forwarding route is replaced with a new forwarding route. In a message transmission device that transmits a message by wireless communication,
A connection information holding unit for holding connection information related to the mutual connection state between terminals;
When the local terminal is the source terminal, the forward route is calculated based on the connection information, with the local terminal serving as the start and end points and passing through all terminals. A forwarding route determination unit that recalculates a new forwarding route for an unforwarded terminal based on the connection information when a message cannot be sent to the terminal that is
If the local terminal is the source terminal, it sends the connection information table that includes the forward route and describes new connection information at the forward destination terminal to the message. If the local terminal is the forward terminal, Describe connection information about the terminal in the connection information table, and send a message to the next forwarding destination terminal. If the terminal is at the end of the forwarding route, it generates receipt certification data indicating the completion of forwarding the message. A data communication unit to transmit
A message transmission device comprising:

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