JP2014116673A - Call connection method, system, terminal and program for switching call connection of telephone line to packet line - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a call connection method, system, terminal and program in which, during a speech or when starting a speech between terminals via a telephone line, the telephone line can be automatically switched to a packet line.SOLUTION: The call connection method includes: a first step of establishing a speed via a telephone line between a first terminal and a second terminal; a second step of converting destination information of the second terminal for a packet line into a voice signal by the second terminal and transmitting the voice signal to the first terminal via the telephone line; a third step of converting the received audio signal into destination information by the first terminal and originating a call towards the second terminal based on the destination information via the packet line; and a fourth step of establishing communication via the packet line between the first terminal and the second terminal. The destination information is a telephone number or a URL address of VoIP for the packet line in the second terminal, or information capable of identifying the telephone number or URL.

Description

  The present invention relates to a technique for automatically switching a call connection of a telephone line to a packet line.

  In recent years, a terminal in a mobile phone or a smartphone is equipped with a plurality of communication interfaces and can be used properly according to usage. Specifically, in the case of a voice call in which users talk to each other, it is preferable to use a telephone line (for example, a 3G network) with the smallest possible delay. On the other hand, in the case of packet communication such as browsing a Web server (for example, the Internet connecting a wireless LAN or WiMAX as an access network), it is preferable to use a packet line with a low communication cost. In the case of a telephone line, voice signals are transmitted / received using an analog signal band, whereas in the case of a packet line, packets are transmitted / received using a digital signal band. In the case of a packet line, a voice call is also possible by using VoIP (Voice over Internet Protocol).

  Conventionally, there is a technique for transmitting a short message that can be transmitted and received between terminals via a telephone line using a DTMF (Dual Tone Multi-Frequency) signal or FSK (Frequency Shift Keying) off-hook signaling within a voice band (for example, Patent Document 1). According to this technique, when a short message is input, the transmission source terminal configures a short message format and establishes communication with the short message service center. Then, the transmission source terminal transmits the short message format to the center in the voice band via the physical layer FSK off-hook signaling. The center transfers the short message to the partner terminal.

  In addition, a technique is described in which a user possesses a mobile phone and a communication device, and realizes two-way communication between the mobile phone connected to the mobile phone network and the communication device connected to the Internet. . Specifically, the mobile phone transmits a command to the communication device using a DTMF signal, and the communication device converts the DTMF signal into an application command, whereby an operation corresponding to the command is executed.

JP2012-75170A JP 2011-507413 A

Senjin-tei, “Introduction to character codes”, [online], [Search December 5, 2012], Internet <URL: http://www.shuiren.org/chuden/teach/code/main3.htm>

  At present, many processor chips that implement a plurality of communication interfaces installed in a terminal cannot use both communication interfaces at the same time. For example, a terminal compatible with CDMA2000 cannot execute packet communication (concurrent communication) for accessing a Web site during a voice call via a telephone line.

  As a specific example, it is assumed that a user calls a call center operator via a telephone line for support. During the conversation here, the operator may want to guide the user's terminal to a specific Web site. However, in this case, the operator must instruct the user to disconnect the telephone line once and access a specific Web site via the packet line again.

  Originally, if it is a packet line, not only packet communication but also a voice call using VoIP is possible. However, a caller who desires a voice call usually calls a partner terminal via a telephone line. This is because there are many cases where the partner terminal does not install the VoIP application, or it is unclear whether it is installed or not even if it is installed. Conversely, if the other terminal desires a voice call based on VoIP via the packet line, it is also preferable for the caller to make a call from the beginning via the packet line having a low communication cost. It should be.

  Therefore, an object of the present invention is to provide a call connection method, system, terminal, and program capable of automatically switching to a packet line during a call between terminals via a telephone line or at the start of a call.

According to the present invention, in a call connection method between a first terminal and a second terminal that can communicate via a telephone line and a packet line,
A first step of establishing a call via a telephone line between a first terminal and a second terminal;
A second step in which the second terminal converts destination information of the second terminal for the packet line into a voice signal and transmits the voice signal to the first terminal via the telephone line;
A third step in which the first terminal converts the received voice signal into destination information and makes a call to the second terminal based on the destination information via the packet line;
And a fourth step of establishing communication between the first terminal and the second terminal via a packet line.

  According to another embodiment of the call connection method of the present invention, the destination information is a VoIP (Voice over Internet Protocol) telephone number or URL (Uniform Resource Locator) address in the second terminal for a packet line, or Information that can specify the telephone number or URL is also preferable.

According to another embodiment of the call connection method of the present invention, for the second step,
The second terminal converts the destination information into a DTMF (Dual Tone Multi-Frequency) audio signal,
It is also preferable that the first terminal converts the received DTMF audio signal into destination information.

  According to another embodiment of the call connection method of the present invention, for the third step, the first terminal disconnects the telephone line call with the second terminal after receiving the voice signal. Is also preferable.

  According to another embodiment of the call connection method of the present invention, for the first step, first, either the first terminal or the second terminal is connected to the second terminal or the second terminal via the telephone line. It is also preferable to make a call to the destination number of one terminal.

  According to another embodiment of the call connection method of the present invention, for the third step, the first terminal automatically starts a VoIP application that uses a packet line and is based on destination information via the packet line. It is also preferable to make a call to the second terminal.

According to another embodiment of the call connection method of the present invention,
For the second step,
The second terminal converts the request information indicating whether or not the VoIP application is installed into a voice signal, and transmits the voice signal to the first terminal via the telephone line;
The first terminal converts the voice signal into request information, confirms installation of the application based on the request information, converts response information based on the confirmation into a voice signal, and converts the voice signal through the telephone line. To the second terminal,
The second terminal converts the received voice signal into response information, and converts the destination information of the second terminal for the packet line into a voice signal only when the response information is already installed. It is also preferable to send the signal to the first terminal via a telephone line.

  According to another embodiment of the call connection method of the present invention, regardless of whether the first terminal and the second terminal are connected by a telephone line or a packet line, the setting and browser It is also preferable to convert the control information into an audio signal and transmit / receive the audio signal.

According to the present invention, in a system having a first terminal and a second terminal equipped with both a telephone line interface and a packet line interface,
The second terminal has a control-side line switching application that converts destination information of the second terminal for the packet line into a voice signal and transmits the voice signal to the first terminal via the telephone line,
The first terminal has a controlled-side line switching application that converts the received voice signal into destination information and makes a call to the second terminal based on the destination information via the packet line. .

According to the present invention, in a terminal equipped with both a telephone line interface and a packet line interface,
A control-side line switching application that converts destination information of the second terminal for a packet line into a voice signal and transmits the voice signal to the first terminal via a telephone line;
And a controlled line switching application for converting the received voice signal into destination information and calling the second terminal based on the destination information via the packet line.

According to the present invention, in a program for causing a computer provided in a terminal equipped with both a telephone line interface and a packet line interface to function,
Control-side line switching application means for converting destination information of the second terminal for the packet line into a voice signal and transmitting the voice signal to the first terminal via the telephone line;
The computer is caused to function as controlled-side line switching application means for converting received voice signals into destination information and making a call to a second terminal based on the destination information via a packet line.

  According to the call connection method, system, terminal, and program of the present invention, terminals can be automatically switched to a packet line during a call or at the start of a call via a telephone line.

It is a system configuration diagram in the present invention. It is a basic sequence diagram in the present invention. It is the sequence diagram which expanded the 2nd step in this invention. It is a control sequence diagram of setting and browser using an audio signal. It is a function block diagram of the terminal in this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a system configuration diagram according to the present invention.

  According to FIG. 1, the terminal 1A and the terminal 1B can be connected to both a telephone line and a packet line. The terminal 1 may be, for example, a mobile phone or a smartphone that can be moved wirelessly, or a personal computer that is fixedly installed by wire. The telephone line is, for example, a mobile phone network or a fixed telephone network, and the packet line is, for example, the Internet connected via an access network. In the following description, it is assumed that the terminal 1 assumed by the present invention can use only one of a telephone line and a packet line.

  In the case of a telephone line, the terminal cannot access the website server during a voice call. Since the telephone line is mainly intended for voice calls, the delay is small, but the transmission capacity is also small. On the other hand, in the case of a packet line, not only can a website server be accessed, but also a voice call between terminals can be made by applying a protocol such as VoIP. However, since the packet line is mainly intended for data communication, it has a large transmission capacity but a relatively large delay.

  ADVANTAGE OF THE INVENTION According to this invention, it can switch to a packet line automatically by control from one terminal at the time of the telephone call between terminals via a telephone line, or the time of a telephone call start. By switching to the packet line, the voice call between the terminals can be continued and the website server can be accessed from the terminals.

  FIG. 2 is a basic sequence diagram in the present invention.

  A terminal switching application (line switching unit) based on the present invention is installed and activated in each of the terminal 1A and the terminal 1B. The line switching application can cause a computer installed in a terminal to function as a control side and a controlled side. In FIG. 2, the calling terminal 1A is described as a controlled side, and the called terminal 1B is described as a controlling side. However, of course, the calling side terminal may be the control side and the called side terminal may be the controlled side.

[S1: First step]
First, a call is established between the terminal 1A and the terminal 1B via a telephone line. According to FIG. 2, a call is established by the terminal 1A calling the terminal 1B via the telephone network.

[S2: Second step]
(S21) The called terminal 1B on the control side converts the destination information of the terminal 1B for the packet line into a voice signal (tone signal). “Destination information” is VoIP (Voice over Internet Protocol) telephone number or URL (Uniform Resource Locator) address or information that can specify the telephone number or URL in the terminal for packet line. The “identifiable information” may be, for example, information designating the telephone number of the terminal 1B among the address information already stored in the terminal 1A.

  The terminal 1B converts the destination information into a DTMF (Dual Tone Multi-Frequency) audio signal. The DTMF signal is a signal sound assigned to each button in, for example, a tone (push) type telephone. In this case, sounds of two kinds of frequencies are transmitted with respect to one button. In general, one sound is combined from each of four types of high-pitched sounds and four types of low-pitched sounds. That is, each alphanumeric character can be expressed as a voice signal. The terminal 1A that has received the DTMF signal can convert it into alphanumeric characters based on this signal sound.

According to FIG. 2, the terminal 1B converts the “operation code request” including the destination information into a DTMF signal. The DTMF signal is obtained by converting, for example, the following alphanumeric characters into a voice signal.
"Operation code request"
130 * <Startup><Control><Value> *
<Startup> 1: Start 0: Stop
<Control> 1: Call connection 0: Confirm
<Value> When control = 1, destination information (for example, VoIP telephone number)
When control = 0, the application code number, for example, when the VoIP telephone number of the terminal 1B is “050-1234-5678” and the call connection is activated, the terminal 1B converts the following alphanumeric characters into a DTMF signal.
130 * 11050125345678 *

(S22) The terminal 1B transmits the voice signal (DTMF signal) to the partner terminal 1A via the voice line.

[S3: Third step]
(S31) The terminal 1A receives an audio signal (DTMF signal) from the terminal 1B. At this time, for example, the user's ear of the terminal 1A can hear “pi”, “po”, “pa”,... From the speaker. Then, the terminal 1A converts the voice information into alphanumeric characters, recognizes an operation code request from the alphanumeric characters, and acquires destination information (for example, a VoIP telephone number) included in the operation code request.

(S32) Here, it is also preferable that the terminal 1A automatically starts a VoIP application (for example, a VoIP application) using a packet line. Thus, at the same time as switching from the telephone network to the packet network, the voice call via the telephone network can be switched to the voice call via the packet network and continued.

(S33) The terminal 1A converts the operation code response into a voice signal (DTMF signal). The DTMF signal is obtained by converting, for example, the following alphanumeric characters into a voice signal.
"Operation code response"
0 * <OK / NG> *
<OK / NG> 1: NG 0: OK
For example, the terminal 1A converts the following alphanumeric characters into a DTMF signal.
0 * 0 *

(S34) The terminal 1A transmits the voice signal to the partner terminal 1B via the voice line.

(S35) The terminal 1B receives an audio signal (DTMF signal) from the terminal 1A. Terminal 1B converts the voice information into alphanumeric characters and recognizes an operation code response from the alphanumeric characters.

(S36) Thereafter, the terminal 1A disconnects the telephone line call with the terminal 1B. It assumes a terminal that cannot be connected to a packet line if a telephone line call is maintained. Then, the terminal 1A makes a call to the terminal 1B based on the destination information via the packet line.

  Here, disconnection of the telephone line in S36 is essential in the case of CDMA2000. On the other hand, according to another communication system, there is a communication system that is disconnected at the same time when a VoIP call is established by subsequent S4. In this case, there is no need to disconnect the telephone line.

[S4: Fourth step]
Finally, communication is established between the terminal 1A and the terminal 1B via the packet line. By starting the VoIP application on both the terminal 1A and the terminal 1B, the voice call can be continued. At the same time, both the terminal 1A and the terminal 1B can access the Web site server 2 connected to the packet network (Internet).

As for the first step (S1), first, either the terminal 1A or the terminal 1B makes a call to the destination number of the terminal 1B or the terminal 1A via the telephone line. According to the present invention, for example, the following three modes of use are conceivable.
(Usage form 1) First, the user of the terminal 1A makes a call to the terminal 1B via a telephone line. It is assumed that the user of the called terminal 1B desires to make a VoIP voice call. At this time, immediately after the incoming call, terminal 1B transmits a DTMF signal converted from the operation code request to terminal 1A. When the user of the calling terminal 1A also permits a VoIP voice call, the terminal 1A returns a DTMF signal converted from the operation code response to the terminal 1B. Thereafter, the voice line is disconnected and packet communication via the packet line is established. Then, the terminal 1A and the terminal 1B can start a VoIP voice call via the packet line.

(Usage form 2) First, the user of the terminal 1B makes a call to the terminal 1A via a telephone line. It is assumed that the user of the calling terminal 1B desires to make a VoIP voice call. At this time, the terminal 1B transmits a DTMF signal obtained by converting the operation code request to the terminal 1A immediately after the incoming call of the terminal 1A. When the user of the called terminal 1A also permits the VoIP voice call, the terminal 1A returns a DTMF signal converted from the operation code response to the terminal 1B. Thereafter, the voice line is disconnected, and packet communication via the packet line is established. Then, the terminal 1A and the terminal 1B can start a VoIP voice call via the packet line.

(Usage mode 3) Either one of the terminal 1A or the terminal 1B makes a call to the destination number of the terminal 1B or the terminal 1A via the telephone line, so that the voice call via the telephone line is established. And Here, when the user of the terminal 1A (for example, a customer) and the user of the terminal 1B (for example, a support center) are having a conversation, the user of the terminal 1B wants to guide the user of the terminal 1A to a specific website. And At this time, the terminal 1B transmits a DTMF signal obtained by converting the operation code request to the terminal 1A. In response to this, the terminal 1A returns a DTMF signal obtained by converting the operation code response to the terminal 1B. Thereafter, the voice line is disconnected, and packet communication via the packet line is established. Then, the terminal 1A and the terminal 1B can continue the VoIP voice call via the packet line and can access the website server via the packet line.

  FIG. 3 is a sequence diagram in which the second step in the present invention is expanded.

(S201) A voice call via a telephone line is established between the terminal 1A and the terminal 1B. At this time, the terminal 1B automatically and automatically sends a voice message “Confirm line switching”. The transmitted voice can be heard by the user's ear of the terminal 1A.
(S202) The terminal 1B converts request information (operation code request) indicating whether or not a VoIP application is installed into a voice signal (DTMF signal). According to FIG. 3, when confirming the application code number (1234) of the terminal 1B, the “operation code request” is the following alphanumeric characters.
130 * 101234
The alphanumeric characters of the operation code request are converted into a DTMF signal.
(S203) The terminal 1B transmits the audio signal (DTMF signal) to the terminal 1A via the telephone line.
(S204) The terminal 1A converts the received audio signal into request information (operation code request).
(S205) The terminal 1A confirms installation of the application based on the request information.
(S206) The terminal 1A converts the response information based on the confirmation into an audio signal. For example, the following alphanumeric characters are converted into audio signals.
For example, the terminal 1A converts the operation code response (OK) into the following DTMF signal. According to FIG. 3, the “operation code response” is the following alphanumeric characters.
0 * 0 *
The alphanumeric characters in the operation code response are converted into a DTMF signal.
(S207) The terminal 1A transmits the audio signal (DTMF signal) to the terminal 1B via the telephone line.
(S208) The terminal 1B converts the received audio signal into response information (operation code response).
(S209) In the case of an operation code response (OK), the terminal 1B sends a voice message “Starts line switching” by voice. The voice is heard by the user of the terminal 1A.
Thereafter, as in FIG. 2, the sequence after S21 is executed.

  FIG. 4 is a control sequence diagram of setting and browser using an audio signal.

  Regardless of whether the first terminal or the second terminal is connected by a telephone line or a packet line, the setting and browser control information is converted into an audio signal, and the audio signal is transmitted and received. To do.

  Assume that the user of the terminal 1A wants to change the WiFi setting of the terminal 1A when the user of the terminal 1A (for example, a customer) and the user of the terminal 1B (for example, a support center) have a conversation. At this time, the terminal 1B transmits a DTMF signal obtained by converting the operation code request (WiFi setting) to the terminal 1A. The application of the terminal 1A can recognize the setting content of the operation code request and can automatically update the WiFi setting.

In addition, when a user of the terminal 1A (for example, a customer) and a user of the terminal 1B (for example, a support center) have a conversation, the user of the terminal 1B wants to guide the user of the terminal 1A to a specific website. To do. At this time, the terminal 1B transmits a DTMF signal obtained by converting the operation code request (browser activation and page transition) to the terminal 1A. The application of the terminal 1A can recognize the setting content of the operation code request and can automatically control the browser.
"Operation code request"
130 * <Startup><Control><Value> *
<Startup> 1: Start 0: Stop
<Control> 3: Browser 4: Page transition
<Value> URL alphanumeric characters For example, when the browser of the page of http://kddi.com is opened, the following alphanumeric characters are converted into a DTMF signal.
130 * 13 http: // kddi. com *

  Note that the alphanumeric characters E to Z cannot be expressed by standard DTMF signals. Therefore, two DTMF signals are expressed in combination. That is, two numeric DTMF signals are combined and expressed as an ASCII code (see Non-Patent Document 1, for example). Specifically, the letter “E” is represented by a combination of numbers “5” and “4”. Further, the alphabet “Z” is expressed by a combination of numbers “A” and “5”. Thus, by expanding the standard DTMF signal, all alphanumeric characters can be expressed by the DTMF signal.

  FIG. 5 is a functional configuration diagram of the terminal in the present invention.

  According to FIG. 5, the terminal 1 executes, in hardware, a voice call interface 101 connected to a telephone line, a packet communication interface 102 connected to a packet line, voice transmission / reception, and display of a Web page. A user interface 103. The voice call interface 101 is, for example, a wireless communication unit that communicates with a mobile phone network, and the packet communication interface 102 is, for example, a wireless communication unit that communicates with a wireless LAN or WiMAX. The user interface 103 includes at least a speaker and a microphone for a user's conversation voice, and a display for displaying a web page.

  Further, according to FIG. 5, the terminal 1 includes a call unit 111, a voice signal conversion unit 112, a data communication unit 121, a VoIP unit 122, and a line switching unit 13. These functions are realized by a program executed by a computer mounted on the terminal 1. When the terminal 1 is a mobile phone or a smartphone, each functional unit is installed as an application.

  The call unit 111 transmits and receives voice signals to and from the voice call interface 101 when connected to the telephone line, and transmits and receives voice signals to and from the VoIP unit 121 when connected to the packet line. On the other hand, the data communication unit 112 transmits and receives packets to and from the packet communication interface 102.

  The voice signal conversion unit 112 converts the alphanumeric text input from the line switching unit 13 into a DTMF signal, and outputs the DTMF signal to the voice call interface 101. Also, the DTMF signal input from the voice call interface 101 is converted into alphanumeric text, and the alphanumeric text is output to the line switching unit 13.

  The VoIP unit 122 converts the voice signal input from the call unit 111 into a VoIP packet and outputs the packet to the packet communication interface 102. In addition, the VoIP packet input from the packet communication interface 102 is converted into a voice signal, and the voice signal is output to the call unit 111.

  The line switching unit 13 has a control side function and a controlled side function. As the “control-side function” (for example, terminal 1B), the destination information of the terminal for the packet line is output to the voice signal conversion unit 112, and the voice signal is transmitted to the terminal 1A via the telephone line. As the “controlled function” (for example, the terminal 1A), the alphanumeric text output from the audio signal converter 112 is input, and the destination information is recognized. Then, the VoIP unit 121 is instructed to make a call to the terminal based on the destination information via the packet line.

  The terminal 1 assumed according to the present invention has been described as being capable of using only one of a telephone line and a packet line. However, the present invention is very effective when a voice call via a telephone line is switched to a voice call via a packet line even if both a telephone line and a packet line can be used simultaneously. It functions as a thing.

  As described above in detail, according to the call connection method, system, terminal, and program of the present invention, terminals can automatically switch to a packet line during a call or at the start of a call via a telephone line. .

  Various changes, modifications, and omissions of the above-described various embodiments of the present invention can be easily made by those skilled in the art. The above description is merely an example, and is not intended to be restrictive. The invention is limited only as defined in the following claims and the equivalents thereto.

DESCRIPTION OF SYMBOLS 1 Terminal 101 Voice call interface 102 Packet communication interface 103 User interface 111 Call part 112 Voice signal conversion part 121 Data communication part 122 VoIP part 13 Line switching part 2 Web server

Claims (11)

In a call connection method between a first terminal and a second terminal capable of communicating via a telephone line and a packet line,
A first step of establishing a call via a telephone line between a first terminal and a second terminal;
A second step in which the second terminal converts destination information of the second terminal for the packet line into a voice signal and transmits the voice signal to the first terminal via the telephone line;
A third step in which a first terminal converts the received voice signal into the destination information and calls a second terminal based on the destination information via a packet line;
A call connection method comprising: a fourth step of establishing communication between a first terminal and a second terminal via a packet line.   The destination information is a VoIP (Voice over Internet Protocol) telephone number or URL (Uniform Resource Locator) address in the second terminal for packet lines, or information that can identify the telephone number or URL. The call connection method according to claim 1, wherein: For the second step,
The second terminal converts the destination information into a DTMF (Dual Tone Multi-Frequency) audio signal,
The call connection method according to claim 1 or 2, wherein the first terminal converts the received DTMF audio signal into the destination information.   4. The third step according to claim 1, wherein, after receiving the audio signal, the first terminal disconnects the telephone line call with the second terminal. 5. The call connection method according to 1.   Regarding the first step, first, either the first terminal or the second terminal calls the destination number of the second terminal or the first terminal via the telephone line. The call connection method according to any one of claims 1 to 4.   The third step is characterized in that the first terminal automatically activates an application for VoIP using a packet line and makes a call to the second terminal based on the destination information via the packet line. The call connection method according to any one of claims 1 to 5. For the second step,
The second terminal converts the request information indicating whether or not the VoIP application is installed into a voice signal, and transmits the voice signal to the first terminal via the telephone line;
The first terminal converts the voice signal into request information, confirms installation of the application based on the request information, converts response information based on the confirmation into a voice signal, and transmits the voice signal via a telephone line. Send the signal to the second terminal,
A second terminal converts the received voice signal into the response information, and converts the destination information of the second terminal for the packet line into a voice signal only when the response information is already installed; The call connection method according to any one of claims 1 to 6, wherein the voice signal is transmitted to the first terminal via a telephone line.   Regardless of whether the first terminal or the second terminal is connected by a telephone line or a packet line, the setting and browser control information is converted into an audio signal, and the audio signal is transmitted and received. The call connection method according to any one of claims 1 to 7, wherein: In a system having a first terminal and a second terminal equipped with both a telephone line interface and a packet line interface,
The second terminal has a control-side line switching application that converts destination information of the second terminal for the packet line into a voice signal and transmits the voice signal to the first terminal via the telephone line,
The first terminal has a controlled line switching application for converting the received voice signal into the destination information and calling the second terminal based on the destination information via the packet line. System. In a terminal equipped with both a telephone line interface and a packet line interface,
A control-side line switching application that converts destination information of the second terminal for a packet line into a voice signal and transmits the voice signal to the first terminal via a telephone line;
A controlled line switching application that converts the received voice signal into the destination information and makes a call to a second terminal based on the destination information via a packet line. In a program for causing a computer provided in a terminal equipped with both a telephone line interface and a packet line interface to function,
Control-side line switching application means for converting destination information of the second terminal for the packet line into a voice signal and transmitting the voice signal to the first terminal via the telephone line;
The computer is caused to function as controlled line switching application means for converting the received voice signal into the destination information and making a call to a second terminal based on the destination information via a packet line. A program for terminals.

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