JPH09191349A - Communication terminal equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To properly inform error information in the case of transfer such as a notice denoting disable transfer execution. SOLUTION: In the case of setting the incoming call transfer mode (affirmative discrimination in the step 104), whether or not a B1 channel is available is discriminated (step 108), and whether or not a B2 channel is available is discriminated (step 112). When either of the B1, B2 channels is not available, a message denoting disable incoming call transfer because no idle channel is in existence in a transfer source terminal equipment is sent to a terminal equipment B being the transfer source terminal equipment (step 110).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication terminal device, and more particularly, to an ISDN network that provides communication services using a D channel for transmitting control information and two B channels for transmitting user data. When a call is received from a source terminal on one of the B channels connected, the other B channel is used to connect to a predetermined transfer destination terminal, and the two B channels are connected so that the source The present invention relates to a communication terminal device having a function of connecting a terminal and a transfer destination terminal and transferring a call from the source terminal to the transfer destination terminal.

[0002]

2. Description of the Related Art Conventionally, with the development of digital communication technology, for example, ISDN (Integrated Service Digital Network), which is one of the services of Nippon Telegraph and Telephone Corporation (NTT).
rk) Net use is widespread. Among the additional services provided by the ISDN network, there is a service called a call transfer service. This call transfer service allows the transfer source terminal to transfer a call received from the source terminal to another terminal (transfer destination terminal), by communicating with the transfer source terminal to the target transfer destination terminal. , The call can be transferred from the transfer source terminal.

However, in order to use the call transfer service provided by this ISDN network, a considerably high fee (NTT
It costs 400 yen to 1000 yen). Therefore, a technique has been proposed in which the function of the terminal is used to perform the call transfer without using the call transfer function of the ISDN network (Japanese Patent Laid-Open No. 2-9075).
No. 8 and Japanese Patent Application Laid-Open No. 2-134948).

As shown in the sequence diagram of FIG. 14, this technique uses one B channel (B1 channel) of the two B channels for control signal transmission in the ISDN network from the source terminal (terminal B). When a call is received, the other B channel (B2 channel) is used to connect to a predetermined transfer destination terminal (terminal C), and these two B channels are connected, so that the source terminal (terminal B) is connected. ) And the transfer destination terminal (terminal C) are connected to transfer the call from the source terminal (terminal B) to the transfer destination terminal (terminal C).

However, in this technique, two Bs are simultaneously formed.
Since a channel is required, when a call is received from a source terminal on one B channel, the transfer cannot be performed if the other B channel is already in use and cannot be used. Further, the sender terminal is not notified that the transfer cannot be executed, and waits until the other B channel becomes available.

Further, during the transfer, two communications are performed between the source terminal and the source terminal and between the source terminal and the destination terminal. For example, the communication between the source terminal and the source terminal is performed. When the transfer is interrupted, the transfer destination terminal is not notified that the transfer has failed, and the transfer destination operator cannot recognize the transfer failure. On the other hand, even when the communication between the transfer source terminal and the transfer destination terminal is interrupted, since the transfer source terminal was not notified that the transfer failed, the operator at the transmission source side can recognize the transfer failure. There wasn't.

Further, when data is being transferred instead of voice, even if communication is interrupted between the transfer source terminal and the transfer destination terminal, not between the transmission source terminal and the transfer source terminal, It was necessary to re-call the transfer source terminal and transfer the data again, which was very troublesome for the sender side.

[0008]

SUMMARY OF THE INVENTION In consideration of the above facts, the present invention provides a communication terminal device capable of accurately notifying error information in transfer such as notification that transfer cannot be executed or notification of transfer failure. A first object of the present invention is to provide a communication terminal device capable of continuing transfer without causing the source terminal to call again when communication between the transfer source terminal and the transfer destination terminal is interrupted during data transfer. Second thing
The purpose of.

[0009]

In order to achieve the first object, a communication terminal device according to claim 1 uses a D channel for transmitting control information and two B channels for transmitting user data. When a call is received from a source terminal on one of the B channels, the other B channel is used to connect to a predetermined transfer destination terminal, and these two B channels are connected. A communication terminal device having a function of connecting a source terminal and a transfer destination terminal by connecting a channel to transfer a call from the source terminal to the transfer destination terminal, and transmitting on one of the B channels. Status determination means for determining whether or not the other B channel is available when a call is received from the former terminal;
When the state determination means determines that the other B channel is not in a usable state, the call transfer impossible notification means notifies the call origination terminal that the call transfer cannot be performed because the transfer source terminal has no channel. , Are included.

In the communication terminal device according to the first aspect, when a call is received from the source terminal on one of the B channels,
The state determining means determines whether or not the other B channel can be used. If it is determined that the other B channel is not available, the call transfer prohibition notification means notifies the call originator terminal that the call transfer cannot be performed because the transfer source terminal has no channel.

As a result, the caller side can recognize that the call transfer is not possible because the transfer source terminal that received the call cannot use the other B channel.

In order to achieve the first object,
The communication terminal device according to claim 2 is connected to an ISDN network that provides a communication service by using a D channel for transmitting control information and two B channels for transmitting user data.
When a call is received from a source terminal on a channel, the other B channel is used to connect to a predetermined transfer destination terminal, and by connecting these two B channels, the source terminal and the transfer destination terminal are connected. A communication terminal device having a function of connecting a call from the source terminal to the transfer destination terminal and disconnecting the communication while transferring the call from the source terminal to the transfer destination terminal. Interruption detection means for detecting,
Interruption notification means for notifying the transfer destination terminal that the communication between the source terminal and the own terminal is interrupted, when the interruption detecting means detects that the communication between the originator terminal and the own terminal is interrupted. It is characterized by having.

In the communication terminal device according to the second aspect of the present invention, when the interruption detecting means detects that the communication between the originator terminal and the own terminal is interrupted, the interruption notifying means detects the communication between the originator terminal and the own terminal. The transfer destination terminal is notified of the interruption.

As a result, the transfer destination can recognize that the communication between the source terminal and the self terminal is interrupted during the transfer.

In order to achieve the first object,
The communication terminal device according to claim 3 is connected to an ISDN network that provides a communication service by using a D channel for transmitting control information and two B channels for transmitting user data.
When a call is received from a source terminal on a channel, the other B channel is used to connect to a predetermined transfer destination terminal, and by connecting these two B channels, the source terminal and the transfer destination terminal are connected. A communication terminal device having a function of connecting a call from the source terminal to the transfer destination terminal and disconnecting the communication while transferring the call from the source terminal to the transfer destination terminal. Interruption detection means for detecting,
Transfer information determining means for determining whether the transferred information is voice or data, and the transfer information determining means for determining that the transferred information is voice and the interruption detecting means for transferring the self-terminal. When it is detected that the communication between the destination terminals is interrupted, a voice interruption notifying means for notifying the originator terminal that the communication between the own terminal and the transfer destination terminal is interrupted,
It is characterized by having.

In the communication terminal device according to the third aspect, the transfer information determining means determines that the information to be transferred is voice, and the interruption detecting means interrupts the communication between the own terminal and the transfer destination terminal. When detected, the voice interruption notifying means notifies the originator terminal that the communication between the own terminal and the transfer destination terminal is interrupted.

As a result, the sender side can recognize that the communication between the transfer source terminal and the transfer destination terminal has been interrupted during the transfer of the voice, and can handle the error such as recalling the transfer source terminal. Can be done quickly.

Further, in order to achieve the second object,
The communication terminal device according to claim 4 is connected to an ISDN network that provides a communication service by using a D channel for transmitting control information and two B channels for transmitting user data.
When a call is received from a source terminal on a channel, the other B channel is used to connect to a predetermined transfer destination terminal, and by connecting these two B channels, the source terminal and the transfer destination terminal are connected. A communication terminal device having a function of connecting a call from the source terminal to the transfer destination terminal and disconnecting the communication while transferring the call from the source terminal to the transfer destination terminal. Interruption detection means for detecting,
Transfer information determining means for determining whether the transferred information is voice or data; and the transfer information determining means for determining that the transferred information is data and the interruption detecting means for transferring the self-terminal. When it is detected that the communication between the destination terminals has been interrupted, the untransferred data storage means for storing the untransferred data that could not be transferred to the transfer destination terminal in a predetermined memory, and the recalled call to the transfer destination terminal, and the memory And an untransferred data transfer means for reading the untransferred data from the device and transferring the untransferred data to the transfer destination terminal.

In the communication terminal device according to the fourth aspect, the transfer information determining means determines that the information to be transferred is data, and the interruption detecting means determines that the communication between the own terminal and the transfer destination terminal is interrupted. Upon detection, the untransferred data storage means stores the untransferred data in a predetermined memory. Then, the untransferred data transfer means recalls the transfer destination terminal,
The untransferred data is read from the memory and transferred to the transfer destination terminal.

As a result, at the time of data transfer, the transfer source terminal-
When the communication between the transfer destination terminals is interrupted, the transfer can be continued without causing the source terminal to call again. That is, the troublesome process of calling again at the sender side is not necessary.

In order to achieve the second object,
The communication terminal device according to claim 5 is, in the communication terminal device according to claim 4, re-calling the transfer destination terminal after accumulating all the untransferred data, or accumulating the untransferred data and transmitting the untransferred data to the transfer destination terminal. Based on the selection means for selecting whether to perform the re-call in parallel and the selection result by the selection means, the re-call to the transfer destination terminal is performed after the untransferred data is stored, or the untransferred data is stored. And selection operation control means for performing re-calling to the transfer destination terminal in parallel.

In the communication terminal device according to the fifth aspect, in the invention according to the fourth aspect, it is determined that the information to be transferred is data and the interruption detecting means interrupts the communication between the own terminal and the transfer destination terminal. When it is detected, the selection means performs the recalling call to the transfer destination terminal after accumulating all the untransferred data, or the accumulation of the untransferred data and the recalling call to the transfer destination terminal are performed in parallel. Or you can choose.

For example, when the capacity of the memory for the untransferred data in the own terminal is small, there is a possibility that all the untransferred data may not be stored in the memory. It is possible to select a person who makes a recall call in parallel.

On the other hand, when it is desired to end the communication between the source terminal and the own terminal early and release one of the B channels early, a method of recalling the destination terminal after accumulating all the untransferred data Can be selected.

Then, the selection operation control means stores all the untransferred data by the untransferred data storage means when it is selected to recall the transfer destination terminal after storing all the untransferred data. Then, the untransferred data transfer means recalls the transfer destination terminal to transfer the untransferred data to the transfer destination terminal. On the other hand, when it is selected to store the untransferred data and call the destination terminal again in parallel, the untransferred data storage means stores the untransferred data and the transfer destination of the untransferred data transfer means. Recall the terminal in parallel.

In this way, it is possible to select and execute an appropriate transfer processing procedure according to the situation.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment] Hereinafter, a first embodiment corresponding to the invention described in claim 1 will be described.

FIG. 1 shows a communication terminal device 10 according to the present invention.
Is shown in FIG. This communication terminal device 10
Is connected to the ISDN network 36 and has a function of using the D channel for transmitting control information and the two B channels for transmitting user data provided by the ISDN network 36.

The ISDN network 36 including the communication terminal device 10 is also included.
Each of the terminals connected to the above and capable of using the above-mentioned D channel and two B channels is preset with a unique identification number (address) of a predetermined digit, and is used when transferring a call through the ISDN network 36. The transfer destination terminal and the transfer source terminal are designated by the address of the corresponding terminal.

The communication terminal device 10 includes:
A CPU 12 that controls the entire apparatus, a ROM 28 that stores in advance a control program for controlling the entire apparatus,
RA as a work area used by control programs, etc.
M14 and are provided.

Further, the communication terminal device 10 includes a non-volatile storage device 16 as a storage device for data which is composed of a magnetic disk device or the like and should be stored even after power-off, and an operator instructs start / stop of various processes. An operation display device 18 including a keyboard for performing operations such as the above and a display for displaying information regarding various processes,
A reading device 20 that reads a transmission original; and encoding, decoding, enlarging,
An image processing device 22 for performing processing such as reduction and an image storage device 24 as a memory dedicated to image data are provided.

It should be noted that the communication terminal device 10 is preset with an incoming call mode for receiving a call from a source terminal as usual or an incoming call transfer mode for forwarding an incoming call to a predetermined transfer destination terminal. The set mode information is stored in advance in the non-volatile storage device 16.

Further, the communication terminal device 10 has, for example, G
4 A communication control unit 30 for controlling communication suitable for digital networks such as facsimile communication, an ISDN network basic interface device 34 for controlling a basic interface for connecting to an ISDN network, and a connection to the ISDN network basic interface device 34. An ISDN network signal processing unit 32 for controlling the second and third layers of the ISDN network, and an ISDN network basic interface device 34.
A switch section 38 connected via two channels of B1 channel and B2 channel for performing switching processing of the B1 channel and B2 channel, and a codec section 40 for performing mutual conversion between an analog signal and a digital signal. There is.

Further, the communication terminal device 10 includes a voice module 44 including a speaker and a microphone, a voice module control unit 42 for controlling the operation of the voice module 44, and a call forwarding process for controlling a call forwarding process. Processing unit 46
And a transmission / reception data memory 48 for storing the transmission data to be transmitted and the received reception data.

Of the above devices, the other devices except the audio module 44 are connected to each other via the system bus 26.

Next, the operation of the first embodiment will be described.
In the following, communication terminal device 10B (hereinafter referred to as terminal B) as a source terminal in call transfer, communication terminal device 10A as a transfer source terminal (hereinafter referred to as terminal A), and terminal A as a transfer destination terminal are registered. Communication terminal device 10C
The error notification process during the call transfer in the three communication terminal devices 10 (hereinafter, referred to as the terminal C) will be described.

In the control routine of FIG. 4 executed by the CPU 12 of the terminal A, in step 102, the SETUP message from the source terminal (here, the terminal B) is waited for. Here, when the terminal B calls the terminal A, the SETUP message from the terminal B is transmitted to the terminal A via the ISDN network as shown in FIG.

When terminal A receives the SETUP message from terminal B, an affirmative decision is made in step 102 of FIG. 4 and the operation proceeds to step 104. In step 104, it is determined whether or not the incoming call transfer mode is set in the terminal A in advance based on the mode information stored in the non-volatile storage device 16.
Step 1 if the incoming call mode is set for terminal A
Proceeding to 06, the normal incoming call process at the terminal A is performed.

On the other hand, when the call transfer mode is set in step 104, the process proceeds to step 108, and it is determined whether or not the B1 channel is available. Here, B1
If the channel is not usable, the process proceeds to step 110, and a message indicating that the call cannot be transferred is transmitted to the terminal B, which is the source terminal, as follows.

That is, the reason display information element 92 is provided at the end of the REL COMP message 90 shown in FIG.
In the reason display value area 92A of the reason display information element 92 shown in (B), a reason display value is added in advance, which means that "call transfer is attempted but the call cannot be transferred because the channel is not available" (for example, # 8). ) Is stored and transmitted to the terminal B. That is, as shown in FIG. 2, a REL CO including a reason display information element in which a reason display value (for example, # 8) is stored.
The MP message (REL COMP (CAUSE) in Fig. 2) is the ISDN network 36.
The data is transferred to the terminal B through the terminal B, and the terminal B side can recognize that “the call transfer is attempted but the call cannot be transferred because the channel is not available” by the reason display value (eg, # 8).

On the other hand, if the B1 channel is available in step 108, the process proceeds to step 112, and it is determined whether the other channel, that is, the B2 channel is available. Here, if the B2 channel is not available, the process proceeds to step 110, and as described above, a message indicating that the call transfer cannot be performed because the channel is not available is transmitted to the terminal B.

If the B2 channel is usable in step 112 (if both the determinations in steps 108 and 112 are positive, that is, if the B1 and B2 channels are both usable), the process proceeds to step 114. , B
The terminal B and the terminal A are connected by one of the channels 1 and B2, and in the next step 116, the terminal A and the terminal C are connected by the other channel.

In the next step 118, B1, B
The two channels are connected by the switch unit 38, and the terminal B-
Communication is started between the terminals C via the terminal A. As a result, the information from the terminal B as the source terminal is successfully transferred to the terminal C as the transfer destination terminal.

After that, when the communication between the terminal B and the terminal C ends (Yes in the communication end determination in step 120),
In step 122, the B1 and B2 channels are released.

As described above, according to the first embodiment, the caller side can recognize that the call cannot be transferred because the transfer source terminal (terminal A) does not have a free channel, and the subsequent action (for example, , Re-calling by changing the destination, waiting for a predetermined time, etc.) can be smoothly selected and executed.

In the first embodiment, in order to notify the terminal B that the call cannot be transferred, a predetermined reason display value is stored in the reason display information element provided at the end of the REL COMP message. Although the embodiment in which the REL COMP message is transmitted is shown, the user / user information element may be provided at the end of the REL COMP message and notification may be performed using the user / user information element.

[Second Embodiment] A second embodiment corresponding to the invention described in claim 2 will be described below. The configuration of the second embodiment is the same as the configuration of the first embodiment, so description will be omitted.

Next, the operation of the second embodiment will be described.
In the following, similar to the operation of the first embodiment, the communication of a total of three terminals, that is, the terminal B as the source terminal in the call transfer, the terminal A as the transfer source terminal, and the terminal C registered in the terminal A as the transfer destination terminal. The error notification processing during the execution of the call transfer in the terminal device 10 will be described.

In the control routine of FIG. 7 which is executed by the CPU 12 of the terminal A, in step 102, SETUP
Wait for a message. Here, when the terminal B makes a call to the terminal A, the SETUP message from the terminal B is transmitted to the terminal A via the ISDN network.

When terminal A receives the SETUP message from terminal B, an affirmative decision is made in step 102 of FIG. 7 and the operation proceeds to step 104. In step 104, it is determined whether or not the incoming call transfer mode is set in the terminal A in advance based on the mode information stored in the non-volatile storage device 16.
When the incoming call mode is set in the terminal A instead of the incoming call transfer mode, the process proceeds to step 106 and the normal incoming call process in the terminal A is performed.

On the other hand, if the call transfer mode is set in step 104, the process proceeds to step 114, and B1, B
The terminal B and the terminal A are connected by one of the two channels (for example, the B1 channel as shown in FIG. 5),
In the next step 116, terminals A and C on the other channel (eg, on the B2 channel as shown in FIG. 5).
And connect.

In the next step 118, the B1 and B2 channels are connected by the switch section 38 as shown in FIG. 5, and the communication between the terminal B and the terminal C is started via the terminal A. As a result, the information from the terminal B as the source terminal is successfully transferred to the terminal C as the transfer destination terminal.

Then, in the next step 119, it is monitored whether the communication between the terminal B and the terminal A is interrupted. When communication between terminal B and terminal A is not interrupted,
In step 120, it is determined whether the communication (transfer) between terminal B and terminal C is completed. Here, if the communication between the terminal B and the terminal C is not completed, the process returns to step 119, while if the communication between the terminal B and the terminal C is completed, the process proceeds to step 122, and the B1 and B2 channels are released. Ends the control routine.

At step 119, the arrow T1 in FIG.
When it is detected that the communication between the terminal B and the terminal A is interrupted, the process proceeds to step 124, and the message indicating that the communication between the terminal B and the terminal A is interrupted is sent to the terminal C as the transfer destination terminal. Is transmitted as follows, and then the communication is ended (step 126).

That is, the DISC message 9 shown in FIG.
The reason display information element 96 is provided at the end of FIG.
In the reason display value area 96A of the reason display information element 96 shown in (4), the reason display value (meaning that the communication between the caller terminal and the transfer source terminal is interrupted during the transfer of the call is interrupted) is given in advance ( For example, # 9) is stored and transmitted to the terminal C. Then, as shown in FIG. 5, it includes a reason display information element in which a reason display value (for example, # 9) is stored.
The DISC message (DISC (CAUSE) in FIG. 5) is transferred to the terminal C via the ISDN network 36. Accordingly, the terminal C side can recognize that “the transfer is interrupted because the communication between the caller terminal and the transferor terminal is interrupted during the call transfer” by the reason display value (for example, # 9).

According to the second embodiment described above, on the transfer destination terminal (terminal C) side, the source terminal (terminal B)-
It can be recognized that the communication between the transfer source terminals (terminal A) is interrupted.

In the second embodiment, the reason display information element provided at the end of the DISC message is used to notify terminal C that communication between terminal B and terminal A has been interrupted during call transfer. Although the embodiment has been shown in which the predetermined reason display value is stored and transmitted together with the DISC message, a user / user information element may be provided at the end of the DISC message and notification may be performed using the user / user information element. .

[Third Embodiment] A third embodiment corresponding to the inventions described in claims 3 and 4 will be described below. The configuration of the third embodiment is the same as the configuration of the first embodiment, so description will be omitted.

Next, the operation of the third embodiment will be described.
In the following, similar to the operation of the first embodiment, the communication of a total of three terminals, that is, the terminal B as the source terminal in the call transfer, the terminal A as the transfer source terminal, and the terminal C registered in the terminal A as the transfer destination terminal. The error handling process during the execution of the call transfer in the terminal device 10 will be described.

In the control routine of FIG. 10 executed by the CPU 12 of the terminal A, SETU is executed at step 102.
P Wait for a message. Here, when the terminal B makes a call to the terminal A, the SETUP message from the terminal B is transmitted to the terminal A via the ISDN network.

When terminal A receives the SETUP message from terminal B, an affirmative decision is made in step 102 of FIG. 10 and the operation proceeds to step 104. In step 104, it is determined whether or not the incoming call transfer mode is set in the terminal A in advance based on the mode information stored in the non-volatile storage device 16. When the incoming call mode is set in the terminal A instead of the incoming call transfer mode, the process proceeds to step 106 and the normal incoming call process in the terminal A is performed.

On the other hand, if the call transfer mode is set in step 104, the process proceeds to step 114, and B1, B
Terminal B and terminal A are connected by one of the two channels (for example, the B1 channel as shown in FIG. 8 or FIG. 9), and in the next step 116, the other channel (for example, FIG. 8 or (B2 channel as shown in Figure 9)
The terminal A and the terminal C are connected.

In the next step 118, B1, B
The two channels are connected by the switch unit 38, and the terminal B-
Communication is started between the terminals C via the terminal A. As a result, the information from the terminal B as the source terminal is successfully transferred to the terminal C as the transfer destination terminal.

Then, in the next step 130, it is monitored whether the communication between the terminals A and C is interrupted. When communication between terminals A and C is not interrupted,
In step 132, it is determined whether the communication (transfer) between terminal B and terminal C is completed. Here, if the communication between the terminal B and the terminal C is not completed, the process returns to step 130, while if the communication between the terminal B and the terminal C is completed, the process proceeds to step 134, and the B1 and B2 channels are released. Ends the control routine.

When it is detected in step 130 that the communication between the terminals A and C is interrupted as indicated by the arrow T2 in FIG. 8 or 9, the process proceeds to step 136, and the transferred information is voiced. It is determined whether or not there is data (that is, whether the communication between the terminal B and the terminal C is voice communication or data communication). Here, if the transferred information is voice, the process proceeds to step 138, and a message to the effect that the communication between the terminals A and C has been interrupted is sent to the terminal B as the source terminal as follows. Then, the communication is terminated (step 140).

That is, as in the second embodiment, as shown in FIG.
A reason display information element 96 is provided at the end of the DISC message 94 shown in FIG. 6A, and the reason display value area 96A in the reason display information element 96 shown in FIG. -The communication between the transfer destination terminals is interrupted, so that the reason display value (for example, # 10) that means "transfer is interrupted" is stored and transmitted to the terminal B. Then, as shown in FIG. 8, the reason display value (for example, # 10)
The DISC message (DISC (CAUSE) in FIG. 8) containing the reason indicating information element in which is stored is transferred to the terminal B via the ISDN network 36. As a result, on the side of the terminal B, the message "Forwarding terminal during call transfer-
The transfer is interrupted because the communication between the transfer destination terminals was interrupted. "
You can recognize that.

On the other hand, if the transferred information is data in step 136, the process proceeds to step 142, and among the data received from the terminal B, the data that has not been transferred to the terminal C (hereinafter referred to as untransferred data). ) Is stored in the transmission / reception data memory 48 (see FIG. 9).

After that, when the communication between the terminal B and the terminal C is completed (when an affirmative judgment is made in step 144), the process proceeds to step 146, and the untransferred data accumulated in the transmission / reception data memory 48 is transmitted to the terminal C.

According to the third embodiment described above, if the communication between the transfer source terminal and the transfer destination terminal is interrupted while the voice is being transferred, the source side has the transfer source terminal and the transfer destination terminal. The occurrence of communication interruption can be recognized.

Further, when the communication between the transfer source terminal and the transfer destination terminal is interrupted at the time of data transfer, the data transfer can be continued without causing the source terminal to call again.

In the third embodiment, in order to notify the terminal B that the communication between the terminal A and the terminal C has been interrupted during the call transfer in the voice communication, the reason display provided at the end of the DISC message is displayed. Although the embodiment in which the predetermined reason display value is stored in the information element and transmitted together with the DISC message is shown, the user / user information element is provided at the end of the DISC message, and notification is performed using the user / user information element. May be.

[Fourth Embodiment] A fourth embodiment corresponding to the invention described in claim 5 will be described below. The configuration of the fourth embodiment is the same as the configuration of the first embodiment, and therefore the description thereof is omitted.

Next, the operation of the fourth embodiment will be described.
In the following, similar to the operation of the first embodiment, the communication of a total of three terminals, that is, the terminal B as the source terminal in the call transfer, the terminal A as the transfer source terminal, and the terminal C registered in the terminal A as the transfer destination terminal. The error handling process during the execution of the call transfer in the terminal device 10 will be described.

First, the operator on the terminal A side, prior to the execution of the call transfer, performs the error handling process in the mode X in which the memory storage of the untransferred data and the recall call are performed in parallel, or the memory storage of the untransferred data is performed. Mode Y to call again after completion
Or is set in advance. The error handling process setting value set here is stored in the RAM 14.

Here, for example, when the capacity of the transmission / reception data memory 48 is small, there is a possibility that all untransferred data cannot be stored in the transmission / reception data memory 48, so the mode X is selected. Further, when it is desired to end the communication between the source terminal and the own terminal earlier and release one B channel earlier, the mode Y is selected.

Thereafter, in the control routine of FIG. 13 executed by the CPU 12 of the terminal A, step 152
Then, the processes of steps 102 to 118 of the control routine of FIG. 10 in the above-described third embodiment are executed, and the communication is set so that the data from the terminal B is transferred to the terminal C via the terminal A. . At this time, the B1 channel between the terminal B and the terminal A, the B2 channel between the terminal A and the terminal C,
Use each.

In the next step 154, it is monitored whether communication via the B2 channel (hereinafter referred to as B2 channel communication) is interrupted. When the B2 channel communication is not interrupted, the process proceeds to step 156, and terminal B-terminal C
It is determined whether or not the communication (transfer) between them is completed. Here, if the communication between the terminal B and the terminal C is not completed, the process returns to step 154, while if the communication between the terminal B and the terminal C is completed, the process proceeds to step 158 and the terminal B via the terminal A is executed. -End communication between terminals C.

On the other hand, in step 154, the process shown in FIG.
When the B2 channel communication is interrupted as indicated by the arrow T3 in FIG. 2, the process proceeds to step 160, and as error handling processing, mode X in which memory accumulation of untransferred data and recalling call are performed in parallel or untransferred data is transferred. The mode Y in which the recalling is performed after the completion of the memory accumulation is selected based on the error handling processing setting value stored in the RAM 14 in advance.

If the mode Y is selected, the process proceeds to step 176, and among the data received from the terminal B, the untransferred data to the terminal C is transmitted / received data memory 4
8 is stored.

After that, as shown in FIG. 11, when the B1 channel communication between the terminal B and the terminal A is completed (step 178).
If a positive determination is made in step S), the process proceeds to step 180 and terminal B
-Perform communication termination processing between terminals A. Next Step 182
Then, the untransferred data accumulated in the transmission / reception data memory 48 is transferred to the terminal C using the B channel which is available at that time.
Send to

For example, even if the B2 channel is unavailable at this time, it is possible to use the B1 channel released by the communication end processing in step 180. Here, it is assumed that the B1 channel is used again as indicated by the arrow T5 in FIG.

After that, when the B1 channel communication between the terminal A and the terminal C is completed (when an affirmative decision is made in step 184), the process proceeds to step 186 and the communication ending process between the terminal A and the terminal C is performed.

On the other hand, when the mode X is selected in step 160, the process proceeds to step 162 and the process of accumulating the untransferred data to the terminal C among the data received from the terminal B in the transmission / reception data memory 48 is started. To do.

In parallel with the accumulation processing of the untransferred data started here, in the next step 164, as in the arrow T4 part in FIG. 12, the terminal C is recalled and B2 is transferred between the terminals A and C. Reconnect with the channel and then the next step 166
Then, the untransferred data accumulated in the transmission / reception data memory 48 is transmitted to the terminal C.

After that, when the B1 channel communication between the terminal B and the terminal A is completed (when an affirmative determination is made in step 168), the process proceeds to step 170, and the communication ending process between the terminal B and the terminal A is performed. Further, when the B2 channel communication between the terminal A and the terminal C is completed (when an affirmative determination is made in step 172), the process proceeds to step 174, and the communication ending process between the terminal A and the terminal C is performed.

According to the fourth embodiment described above, the mode X or the mode Y can be set according to the situation,
An appropriate error handling procedure can be executed according to the error handling processing mode set at the time of executing the call transfer.

[0087]

According to the invention described in claim 1, it is possible for the caller side to recognize that the call transfer cannot be performed because the transfer source terminal that received the call cannot use the other B channel. You can get the effect.

According to the second aspect of the invention, the transfer destination side can recognize that the communication between the source terminal and the self terminal is interrupted during the transfer.

According to the third aspect of the invention, the source side can recognize that the communication between the transfer source terminal and the transfer destination terminal is interrupted during the transfer of the voice, and the transfer source terminal is notified. The effect that it is possible to promptly deal with an error such as recalling is obtained.

According to the invention described in claim 4, when the communication between the transfer source terminal and the transfer destination terminal is interrupted at the time of data transfer, the transfer can be continued without causing the source terminal to call again. The effect of, is obtained.

Further, according to the invention described in claim 5, it is possible to obtain an effect that an appropriate transfer processing procedure can be selected and executed according to the situation.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of a communication terminal device according to first to fourth embodiments.

FIG. 2 is a sequence diagram showing a communication procedure between a terminal A and a terminal B in the first embodiment.

FIG. 3A is a diagram showing a configuration example of a REL COMP message, and FIG. 3B is a diagram showing a configuration example of a reason display information element.

FIG. 4 is a flow chart showing a control routine executed by terminal A in the first embodiment.

FIG. 5 is a terminal A, a terminal B, and a terminal C according to the second embodiment.
It is a sequence diagram which shows the communication procedure between.

FIG. 6A is a diagram showing a configuration example of a DISC message, and FIG. 6B is a diagram showing a configuration example of a reason display information element.

FIG. 7 is a flowchart showing a control routine executed by the terminal A in the second embodiment.

FIG. 8 is a sequence diagram showing a communication procedure among terminals A, B, and C at the time of voice transfer in the third embodiment.

FIG. 9 is a terminal A at the time of data transfer in the third embodiment,
It is a sequence diagram which shows the communication procedure between the terminal B and the terminal C.

FIG. 10 is a flow chart showing a control routine executed by terminal A in the third embodiment.

FIG. 11 shows a terminal A, a terminal B, and a terminal C when transferring untransferred data after accumulating the untransferred data in the fourth embodiment.
It is a sequence diagram which shows the communication procedure between.

FIG. 12 is a sequence diagram showing a communication procedure among terminals A, B, and C when transferring untransferred data in parallel with the accumulation of untransferred data in the fourth embodiment.

FIG. 13 is a flow chart showing a control routine executed by the terminal A in the fourth embodiment.

FIG. 14 shows a terminal A, a terminal B when executing a conventional call transfer,
It is a sequence diagram which shows the communication procedure between the terminals C.

[Explanation of symbols]

 10 communication terminal device 12 CPU 36 ISDN network 46 incoming call transfer processing unit 48 transmission / reception data memory (memory)

Claims (5)

[Claims] 1. Connected to an ISDN network that provides communication services using a D channel for transmitting control information and two B channels for transmitting user data, and a call is received from a source terminal on one of the B channels. In this case, the other B channel is used to connect to a predetermined transfer destination terminal, and these two B channels are connected.
A communication terminal device having a function of connecting a source terminal and a transfer destination terminal by connecting a channel to transfer a call from the source terminal to the transfer destination terminal, and transmitting on one of the B channels. When a call is received from the former terminal, the state determination means determines whether or not the other B channel is available, and the state determination means determines that the other B channel is not available. In this case, there is provided a communication terminal device comprising: a call transfer impossible notification means for notifying the caller terminal that the call cannot be transferred because the channel is not available at the transfer source terminal. 2. A D channel for transmitting control information and two B channels for transmitting user data are connected to an ISDN network that provides communication services, and a call is received from a source terminal on one of the B channels. In this case, the other B channel is used to connect to a predetermined transfer destination terminal, and these two B channels are connected.
A communication terminal device having a function of connecting a source terminal and a transfer destination terminal by connecting a channel and transferring a call from the source terminal to the transfer destination terminal, wherein the call from the source terminal is During the transfer to the transfer destination terminal, the interruption detecting means for detecting the interruption of the communication, and the interruption detecting means detects the interruption of the communication between the originator terminal and the own terminal, the originator terminal- A communication terminal device having: interruption notification means for notifying the transfer destination terminal that communication between the terminals itself has been interrupted. 3. A D channel for transmitting control information and two B channels for transmitting user data are connected to an ISDN network that provides communication services, and one B channel receives a call from a source terminal. In this case, the other B channel is used to connect to a predetermined transfer destination terminal, and these two B channels are connected.
A communication terminal device having a function of connecting a source terminal and a transfer destination terminal by connecting a channel and transferring a call from the source terminal to the transfer destination terminal, wherein the call from the source terminal is An interruption detection unit that detects that communication is interrupted during transfer to the transfer destination terminal, transfer information determination unit that determines whether the transferred information is voice or data, and the transfer information determination unit When it is determined that the information to be transferred is voice and the interruption detecting unit detects that the communication between the self terminal and the transfer destination terminal is interrupted, the communication between the self terminal and the transfer destination terminal is interrupted. And a voice interruption notifying means for notifying the source terminal of 4. A D channel for transmitting control information and two B channels for transmitting user data are connected to an ISDN network that provides communication services, and one B channel receives a call from a source terminal. In this case, the other B channel is used to connect to a predetermined transfer destination terminal, and these two B channels are connected.
A communication terminal device having a function of connecting a source terminal and a transfer destination terminal by connecting a channel and transferring a call from the source terminal to the transfer destination terminal, wherein the call from the source terminal is An interruption detection unit that detects that communication is interrupted during transfer to the transfer destination terminal, transfer information determination unit that determines whether the transferred information is voice or data, and the transfer information determination unit It is determined that the information to be transferred is data, and the interruption detecting means determines the terminal itself.
When it detects that the communication between the transfer destination terminals is interrupted,
Untransferred data storage means for storing untransferred data that could not be transferred to the transfer destination terminal in a predetermined memory, and recalling to the transfer destination terminal, reading the untransferred data from the memory, and transferring the untransferred data to the transfer destination terminal An untransferred data transfer means for transferring to a communication terminal device. 5. A selection means for selecting whether to recall the transfer destination terminal after accumulating all the untransferred data, or to store the untransferred data and recall the transfer destination terminal in parallel. And selection based on the selection result by the selecting means to call the transfer destination terminal again after storing the untransferred data, or to store the untransferred data and call the call again to the transfer destination terminal in parallel. The communication terminal device according to claim 4, further comprising: an operation control unit.