JP2000031875A - Communication terminal device, communication controller and data communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To confirm whether it is the abnormality occurrence or power off of each terminal and to make management easy and also sure by notifying the effect to a communication controller and after that turning off power when each terminal turns it off. SOLUTION: A slave station 500 drives a radio unit 302 and transmits notification data of power off to a center station 400 when a power switch 306 is subjected to a switching operation from on to off by the processing operation of a body controlling part 501 according to a control program. When the station 400 receives the power off data, it stores it in a recoding medium of a DAMA controlling part 401 and also transmits receiving notification data to the station 500. The station receives the receiving notification data, confirms it and after that turns off the body power by means of the part 501. Thus, the terminal testing function of the station 400 discriminates whether or not due to the power off in deciding the existence of abnormality of each slave station according to the existence of response data from each slave station to data transmission and can appropriately copes with it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a data communication system in which a communication control device controls data communication of a plurality of communication terminal devices via a communication satellite.

[0002]

2. Description of the Related Art At present, a data communication system using a communication satellite for telephone communication or the like has been put into practical use, and a DAMA (Demand) is used as a communication system for effectively utilizing a finite communication line.
Assignment Multiple Access) is used. In the data communication system of the DAMA system, when a plurality of communication terminal devices open a communication line with a communication satellite and perform data communication with each other, the communication control device allocates a communication line with the communication satellite to the plurality of communication terminal devices. .

A conventional example of such a data communication system of the DAMA system will be described below with reference to FIG. FIG. 1 is a schematic diagram showing the entire structure of the data communication system.

[0004] The data communication system 1 exemplified here is composed of:
It comprises at least one communication satellite 100, at least one center station 200, and a number of slave stations 300. The communication satellite 100 includes the communication antenna 101 and the wireless unit 1
The wireless unit 102 performs data communication with the center station 200 and the slave station 300 by the communication antenna 101.

[0005] The center station 200 includes a communication antenna 201,
The mobile station 300 includes a wireless unit 202, a DAMA control unit 203, an input / output device 204, and the like. The slave station 300 includes a communication antenna 301, a wireless unit 302, a DAMA control unit 303, an input / output device 304, a main body power supply 305, a power switch. 306, etc.

The wireless units 202 and 302 wirelessly communicate with the communication satellite 100 by the DAMA method using the communication antennas 201 and 302, and the DAMA control units 203 and 303 control the operation of the wireless communication by the wireless units 202 and 302. The input / output devices 204 and 304 are CRT (Cathode
-Ray Tube) It consists of a display, a keyboard, etc., and executes input and output of various data.

The main power supply 305 of the slave station 300 supplies power to each of the units 302 to 304 as described above, and the power switch 306 switches on / off of the main power supply 305. The communication satellite 100 and the center station 200 are, of course,
Also has a main body power supply, but this is not related to the present invention, so illustration and description are omitted.

In the above-described configuration, in the conventional data communication system 1, a plurality of slave stations 300 are
0 through the DAMA system. In this case, since the center station 200 performs data communication with the communication satellite 100 and allocates a communication line that is not currently used to the slave stations 300, these slave stations 300 can execute data communication on the assigned communication lines. .

In such a data communication system 1, the center station 2 is used to allocate communication lines as described above.
00 needs to recognize the current state of many slave stations 300, the DAMA control unit 203 of the center station 200 includes:
A slave station database (not shown) that holds the current state for each of the identification data of the slave stations 300 is constructed.

The center station 200 transmits the health check communication data from the communication satellite 100 to each of the plurality of slave stations 300 at a predetermined timing, and the slave station 300 that has received the data transmits the predetermined response data. Data is transmitted to the communication satellite 100.

The result of this response is transmitted from the communication satellite 100 to the center station 200.
0 can hold the data of the current state of many slave stations 300. For example, when there is a slave station 300 that does not transmit response data even when communication data for health check is transmitted, the center station 200 recognizes the state of the slave station 300 as abnormal.

Then, the center station 200 notifies the manager (not shown) of the abnormality of the slave station 300 by displaying the data of the input / output unit 204 or the like. And the data communication system 1 can be quickly returned to a normal state.

[0013]

In the data communication system 1 as described above, the state of the plurality of slave stations 300 is integrated and managed by the center station 200, so that the plurality of slave stations 300 transmit data via the communication satellite 100. Can communicate.

However, the operator of the slave station 300 (not shown)
When the main unit power supply 305 is turned off by manual operation of the power switch 306 to temporarily suspend the operation, the slave station 300 does not transmit response data even if communication data for health check is transmitted. .

Therefore, the center station 200 also recognizes that the slave station 300 with the main body power supply 305 turned off is abnormal, and the manager of the center station 200 starts work to resolve the malfunction of the slave station 300. Become. However, if the operator intentionally turns off the main power supply 305 of the slave station 300, the main power supply 305 of the slave station 300 is turned on as desired by the operator, so that the center for restoring the slave station 300 is turned on. The work of the administrator of the station 200 is useless.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has a communication terminal device and a power supply for a communication terminal device that allow a communication control device to recognize an off state of a main body power supply by manually operating a power switch. An object of the present invention is to provide a communication control device capable of distinguishing off from occurrence of an abnormality, a data communication system including such a communication terminal device and a communication control device, and the like.

[0017]

A data communication system to which the present invention is applied includes a communication satellite, a plurality of communication terminal devices for performing data communication with each other via the communication satellite, and A communication control device for allocating a communication line to a communication satellite.

A first communication terminal device of the present invention applied to the data communication system as described above includes a main body power supply for supplying power to each section, a power switch for switching on / off of the main body power supply, Status transmitting means for transmitting notification data of power off to the communication control device when the power switch is switched from on to off, and after the data transmission by the status transmitting means is completed, Power supply switching means for switching to an off state.

Therefore, in the communication terminal device of the present invention, the main body power supply supplies power to each section, and the on / off of the main body power supply is switched by the power switch. However, when the power switch is switched from the on state to the off state, the power-off notification data is transmitted to the communication control device by the status transmitting means. After the data transmission is completed, the power supply is switched off by the power supply switching means, so that the communication control device is notified of the power off of the communication terminal device by data.

According to a second communication terminal device of the present invention, there is provided a main body power supply for supplying power to each section, a power switch for switching ON / OFF of the main body power supply, and switching the power switch from an ON state to an OFF state. Status transmission means for transmitting power-off notification data to the communication control device when operated,
Reply receiving means for receiving data of reply data of the communication control device corresponding to data transmission by the status transmitting means,
Power supply switching means for switching off the main body power supply after the reply data is received by the reply receiving means.

Therefore, in the communication terminal device of the present invention, the main body power supply supplies power to each section, and the on / off of the main body power supply is switched by the power switch. However, when the power switch is switched from the on-state to the off-state, the power-off notification data is transmitted to the communication control device by the status transmission means, and the reply data of the communication control device corresponding to this data transmission is returned. The data is received by the receiving means. Since the power of the main body is switched off by the power supply switching means after the data is received, the power of the communication terminal is turned off after the data is received by the communication control device.

The communication control apparatus of the present invention applied to the data communication system as described above includes a status receiving means for receiving power-off notification data from the communication terminal apparatus;
Status holding means for holding the power-off data data received by the status receiving means together with the identification data of the communication terminal device; and data communication with the plurality of communication terminal devices to determine the presence or absence of an abnormality based on a response result And a test correction means for invalidating the abnormality determined by the terminal test means with respect to the communication terminal device in which power-off data is held in the status holding means. .

Accordingly, in the communication control device of the present invention, the terminal inspection means performs data communication with a plurality of communication terminal devices and determines whether or not there is an abnormality based on a response result. To be discovered. However, when the power-off notification data is received from the communication terminal device by the status receiving unit, the power-off when the notification data is received is held by the status holding unit together with the identification data of the communication terminal device. The abnormality determined by the terminal inspection unit is invalidated by the inspection correction unit for the communication terminal device in which the power is turned off in the status holding unit. Is not determined to be abnormal.

In the communication control apparatus as described above, it is also possible to include an off notification means for notifying and outputting the power-off data held by the status holding means together with the identification data of the communication terminal apparatus. In this case, the power-off data held by the status holding unit is notified and output by the OFF notification unit together with the identification data of the communication terminal device, so that the power-off of the communication terminal device is notified to the administrator of the communication control device.

[0025] In the communication control apparatus as described above, it is possible to include a reply transmitting means for transmitting reply data to the communication terminal device, to which the notification data has been received by the status receiving means. In this case, since the reply data is transmitted by the reply transmitting means to the communication terminal device to which the notification data has been received by the status receiving means, the communication control device confirms that the communication terminal device has received the power-off notification data. Can respond.

A data communication system according to the present invention includes the communication terminal device according to the present invention and the communication control device according to the present invention. Therefore, in the data communication system of the present invention, the communication terminal device executes the process after notifying the communication control device of power-off data. Alternatively, since the communication terminal device notifies the communication control device of the power-off, the communication terminal device performs power-off when the communication control device responds with data.

The various means referred to in the present invention only need to be formed so as to realize their functions. For example, dedicated hardware, a computer provided with appropriate functions by a program, a computer provided by an appropriate program , The functions realized inside, and the combination thereof are allowed.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. However, the same portions as those of the conventional example described above with respect to the present embodiment are denoted by the same names and reference numerals, and detailed description thereof is omitted. 1 is a schematic diagram illustrating a data communication system according to the present embodiment, FIG. 2 is a flowchart illustrating a data processing method of a slave station as a communication terminal device, and FIG. 3 is a data processing method of a center station as a communication control device. It is a flowchart which shows.

The data communication system 2 of the present embodiment also
As shown in FIG. 1, at least one communication satellite 10 is provided similarly to the data communication system 1 described above as a conventional example.
0, at least one center station 40 which is a communication control device
0, a large number of slave stations 500, which are communication terminal apparatuses.

The center station 400 includes a communication antenna 201,
The mobile station 500 includes a wireless unit 202, a DAMA control unit 401, an input / output device 204, and the like. The slave station 500 includes a communication antenna 301, a wireless unit 302, a DAMA control unit 303, an input / output device 304, a main body power supply 305, a power switch. 306, a main body control unit 501, and the like.

The wireless units 202 and 302 wirelessly communicate with the communication satellite 100 by the DAMA method using the communication antennas 201 and 302, and the DAMA control units 401 and 303 control the operation of the wireless communication by the wireless units 202 and 302. The input / output devices 204 and 304 include a CRT display, a keyboard, and the like, and execute input and output of various data.

The main unit power supply 305 of the slave station 500 supplies power to each of the units 302 to 304 and 501 as described above, and the power switch 306 switches on / off of the main unit power supply 305. However, unlike the above-described slave station 300 of the related art, the slave station 500 according to the present embodiment does not have the power switch 306 and the main body power supply 305 directly connected to each other, and is connected through the main body control unit 501. Have been.

The main body control section 501 is composed of a microcomputer in which an appropriate control program is implemented as software, and executes various processing operations in accordance with the implemented control program. Therefore, the slave station 500
Various functions, such as a status transmission function as a status transmission unit, a reply reception function as a reply reception unit, and a power supply switching function as a power supply switching unit, are logically realized as various units.

Similarly, the DMM control unit 4 of the center station 400
Reference numeral 01 includes a computer system (not shown) in which an appropriate control program is implemented as software, and executes various processing operations in accordance with the control program in which the computer system is implemented.

Therefore, the center station 400 has a status receiving function as a status receiving means, a slave station database corresponding to a status holding means, a reply transmitting function as a reply transmitting means, a terminal inspecting function as a terminal inspecting means, Various functions such as an inspection correction function as a correction unit and an OFF notification function as an OFF notification unit are logically realized as various units.

When the power switch 306 is switched from the on state to the off state by the processing operation of the main body control unit 501 corresponding to the control program, the status transmission function of the slave station 500 drives the radio unit 302 and the like. The power off notification data is transmitted to the center station 400.

The status receiving function of the center station 400 receives power-off notification data from the slave station 500 by the wireless unit 202 or the like by the processing operation of the DAMA control unit 401 corresponding to the control program. Predetermined reply data is transmitted from the wireless unit 202 or the like to the slave station 500 that has received the power-off notification data.

In the same manner, by the processing operation corresponding to the control program, the reply receiving function of the slave station 500
The reply data of 00 is received by the wireless unit 302 or the like, and the power supply switching function switches the main body power supply 305 to the off state by the main body control unit 501 after the data is received.

The slave station database of the center station 400 is built in advance in an information storage medium such as an HDD (Hard Disc Drive) provided in the computer system of the DMM control unit 401, and stores a large number of slave stations 500. The current communication status, presence / absence of abnormality,
On / off of the data 05 is stored in an updatable manner.

The terminal inspection function of the center station 400 transmits so-called health check communication data to each of a large number of slave stations 500 by the wireless unit 202 or the like, and checks whether response data corresponding to this data transmission has been received. It is determined whether or not the station 500 is abnormal.

The inspection correction function is performed when the slave station 500 is determined to be abnormal by the above-described terminal inspection function.
If the power-off of the slave station 500 is stored in the slave station database, the determination result of the slave station 500 as invalid is invalidated. The off-notification function, for example, notifies the administrator (not shown) of the power-off stored in the slave station database together with the identification data of the slave station 500 by displaying data on the CRT display of the input / output unit 204.

The center station 400 and the slave station 5 as described above.
00 of the wireless units 202 and 3
02 is implemented by using hardware such as a hardware computer, which operates in accordance with a control program implemented as software.

For example, the microcomputer of the main body control unit 501 of the slave station 500 detects the switching operation of the power switch 306 from the ON state to the OFF state, and when this operation is detected, drives the wireless unit 302 and the like. Transmitting power off notification data to the center station 400,
A control program for processing operations such as receiving the reply data of the center station 400 corresponding to the data transmission by the wireless unit 302 or the like, and switching the main body power supply 305 to an off state when the reply data is received, is provided. Has been implemented.

The DAMA control unit 4 of the center station 400
01, the power-off notification data transmitted from the slave station 500 is transmitted to the wireless unit 20.
2 and the like, when the data is received, the predetermined reply data is transmitted to the corresponding slave station 500 by the wireless unit 202 or the like, and the power-off notification data is received. Holding the data in the slave station database together with the identification data of 500, and transmitting the communication data of the health check to the wireless unit 202.
Transmitting data to each of the large number of slave stations 500 by determining the presence / absence of abnormality in the slave station 500 based on the presence / absence of data reception of response data corresponding to this data transmission;
If the power-off of the slave station 500 determined to be abnormal is held in the slave station database, the slave station 500
Control of processing operations, such as invalidating the determination result as an abnormality of the slave station, notifying the power-off stored in the slave station database together with the identification data of the slave station 500 by displaying data on the input / output unit 204, and the like. The program has been implemented.

In the above-described configuration, in the data communication system 2 of the present embodiment, similarly to the conventional data communication system 1, a plurality of slave stations 500 perform data communication with the DAMA system via the communication satellite 100. Can be. In this case, since the center station 400 performs data communication with the communication satellite 100 and allocates a communication line that is not currently used to the slave stations 500, these slave stations 500 can execute data communication using the allocated communication lines. .

However, in the slave station 500 of the data communication system 2 of the present embodiment, as shown in FIG. 2, the power switch 306 is turned off from the on state during the normal operation as described above. The main body control unit 501 constantly monitors the switching operation to the state (steps S1 and S2).

When the power switch 306 is actually switched from the ON state to the OFF state, the operation of the wireless unit 302 and the like is controlled by the main body control unit 501, and predetermined notification data indicating power OFF is sent to the center station 400. Data is transmitted (step S3).

As shown in FIG. 3, the center station 400 of the present embodiment that performs data communication with the slave station 500 transmits the notification data transmitted from the slave station 500 during the normal operation. Waiting for the data reception and the execution timing of the regular health check (steps T1 to T3).

Therefore, in the center station 400 which has received the power-off notification data from the slave station 500, the DAMA control unit 401 updates the setting data of the corresponding slave station 500 in the slave station database to the power-off state (step T4). ), When this is completed, the slave station 500 that has transmitted the notification data.
Then, predetermined reply data is transmitted by the wireless unit 202 or the like (step T5).

As shown in FIG. 2, in the slave station 500 that has received the reply data transmitted from the center station 400 by the wireless unit 302 or the like (step S4), the main body controller 501 responds to the data reception. The main body power supply 305 is turned off (step S5).

In the case where the slave station 500 according to the present embodiment does not receive the reply data from the center station 400, the data transmission of the notification data is repeated (step S3).
S4, S6), if this data transmission is repeated a specified number of times, it is determined that an error has occurred.

The center station 400 according to the present embodiment
As shown in FIG. 3, health checks of a large number of slave stations 500 are periodically executed at preset timings.
(Step T2). In this case, one of the slave stations 500 for which a health check is to be performed is sequentially selected (step T).
6) The communication data of the predetermined health check is transmitted to the selected slave station 500 (step T7).

The slave station 500 which has received the communication data of the health check transmits predetermined response data to the center station 400 as a normal operation, so that the center station 400 can receive the response data. 500
Is determined to be normal (steps T8 and T11), and the above-described processing operation is executed in all the slave stations 500 (step T1).
3, T6).

However, when the slave station 500 that has transmitted the health check communication data cannot transmit the response data (step T8), the center station 4 of this embodiment does not transmit the response data.
00 searches the slave station database for the setting data of the slave station 500 (step T9).

If the power-off of the slave station 500 is set in the slave station database, the slave station 50
0 is determined to be normal (step T11), and if the power-off of the slave station 500 is not set in the slave station database, the slave station 500 is determined to be abnormal (step T1).
2).

It should be noted that a number of slave stations 5 determined in this way
The normal / abnormal 00 is displayed to the administrator on the CRT display of the input / output unit 204 as a result of the health check, for example.
The on / off of 05 is also displayed and output at the same time.

When the power switch 306 is switched from the ON state to the OFF state, the slave station 500 according to the present embodiment notifies the center station 400 of the power-off and receives reply data from the center station 400. Power supply 3
05 is turned off, the power is turned off at the center station 400.
Can be reliably notified.

The center station 400 according to the present embodiment is
When the power-off is notified from 00, the corresponding reply data is transmitted to the slave station 500, so that the power-off acknowledgment can be responded to the slave station 500. It can be executed quickly.

Further, the power-off of the slave station 500 notified of the data is set in the slave station database, and the slave station 50 whose power-off is set in the slave station database.
Since 0 is not determined to be abnormal when the health check is executed,
It is possible to prevent confusion between occurrence of an abnormality in the slave station 500 and power off.

Moreover, since the power-off stored in the slave station database can be notified and output together with the identification data of the slave station 500, the manager of the center station 400 can check the slave station 50.
0 can be reliably confirmed, and only the slave station 500 in which the abnormality has occurred can perform the recovery work.

The present invention is not limited to the above-described embodiment, but allows various modifications without departing from the scope of the invention. For example, in the above-described embodiment, the example has been described in which the slave station 500 executes the power-off after receiving the reply data from the center station 400 to which the power-off is notified.

However, the slave station 500 transmits the power-off notification data to the center station 400 without the requirement that the slave station 500 receive the reply data as described above, and then turns off the main power supply 305 unilaterally. It is also possible to switch to. In this case, the slave station 500
There is a possibility that the center station 400 will not reliably recognize that the power supply is turned off, but the processing operations of the center station 400 and the slave station 500 can be simplified.

In the above embodiment, various functions are realized as various means by the software suitable for the center station 400 and the slave station 500. However, for example, each of these various functions is individually formed as hardware. It is also possible to realize a part by software and to form a part as hardware.

[0064]

Since the present invention is configured as described above, it has the following effects.

In the first communication terminal device of the present invention, when the power switch of the main power supply for supplying power to each unit is switched from the on state to the off state, the power-off notification data is transmitted to the communication control unit by the status transmitting unit. The data is transmitted to the device, and after the data transmission is completed, the main body power is switched off by the power supply switching means, so that the communication control device can be notified of the power-off of the communication terminal device by the data. It is possible to make the device recognize that the power of the communication terminal device is turned off and distinguish it from the occurrence of an abnormality.

In the second communication terminal device according to the present invention, when the power switch of the main power supply for supplying power to each unit is switched from the on state to the off state, the status transmitting means transmits the power-off notification data to the communication control unit. When data is transmitted to the device and reply data of the communication control device corresponding to the data transmission is received by the reply receiving means, the power supply is switched off by the power supply switching means after the reply data is received. Thereby, it is possible to notify the communication control device of the power-off of the communication terminal device by data,
Since it is possible to confirm that the power-off is received by the communication control device, it is possible to make the communication control device surely recognize the power-off of the communication terminal device and distinguish it from the occurrence of an abnormality.

In the communication control device according to the present invention, the terminal inspection means performs data communication with a plurality of communication terminal apparatuses to determine the presence or absence of an abnormality based on a response result. When the data is received, the power-off when the notification data is received is held by the status holding unit together with the identification data of the communication terminal device, and when the abnormality is determined by the terminal inspection unit, the power-off is held by the status holding unit. By invalidating the communication terminal device that has been set by the inspection correction unit, it is possible to prevent confusion between turning off the power of the communication terminal device and occurrence of an abnormality.

In the communication control apparatus as described above, the power-off data held by the status holding means is notified and output by the off-notifying means together with the identification data of the communication terminal apparatus. OFF can be surely recognized by the administrator of the communication control device.

In the communication control apparatus as described above, the power-off notification data is received by transmitting the reply data by the reply transmission means to the communication terminal device to which the notification data has been received by the status receiving means. This can be responded to the communication terminal device, so that the power of the communication terminal device can be quickly turned off.

In the first data communication system of the present invention,
The communication terminal device notifies the communication control device of the power-off after executing the data, so that the communication control device can recognize the power-off of the communication terminal device.

In the second data communication system of the present invention,
The communication terminal device notifies the communication control device of power-off data, and when the communication control device responds to the data, the communication terminal device executes power-off, whereby the communication control device reliably recognizes the power-off of the communication terminal device. be able to.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a data communication system according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating a data processing method of a slave station that is a communication terminal device.

FIG. 3 is a flowchart illustrating a data processing method of a center station that is a communication control device.

FIG. 4 is a schematic diagram showing a data communication system of a conventional example.

[Explanation of symbols]

 2 data communication system 100 communication satellite 305 main power supply 306 power switch 400 center station 401 DAMA control section functioning as various means 500 slave station 501 main body control section functioning as various means

Claims (7)

[Claims] 1. A communication satellite comprising: a communication satellite; a plurality of communication terminal devices for mutually performing data communication via the communication satellite; and a communication control device for assigning a communication line to the communication satellite to the plurality of communication terminal devices. In a data communication system, a main power supply for supplying power to each unit, a power switch for switching on / off of the main power, and a power off when the power switch is switched from an on state to an off state Communication terminal device comprising: status transmitting means for transmitting the notification data to the communication control device; and power supply switching means for switching off the main body power supply after the data transmission by the status transmitting means is completed. . 2. A communication satellite comprising: a communication satellite; a plurality of communication terminal devices for mutually performing data communication via the communication satellite; and a communication control device for assigning a communication line with the communication satellite to the plurality of communication terminal devices. In a data communication system, a main power supply for supplying power to each unit, a power switch for switching on / off of the main power, and a power off when the power switch is switched from an on state to an off state Status transmitting means for transmitting the notification data of the communication control device to the communication control device, reply receiving means for receiving the reply data of the communication control device corresponding to the data transmission by the status transmitting device, and reply data by the reply receiving means. Power supply switching means for switching off the main body power supply after receiving the data. 3. A communication satellite comprising: a communication satellite; a plurality of communication terminal devices for mutually communicating data via the communication satellite; and a communication control device for assigning a communication line to the communication satellite to the plurality of communication terminal devices. In a data communication system, a status receiving unit for receiving data of power-off notification data from the communication terminal device, and a power-off state in which the notification data is received by the status receiving unit together with identification data of the communication terminal device Status holding means for holding data; terminal inspection means for performing data communication with the plurality of communication terminal devices to determine the presence or absence of an abnormality based on a response result; and powering off the status holding means for the abnormality determined by the terminal inspection means. And a test correction unit that invalidates the communication terminal device in which the data is stored. 4. The communication control apparatus according to claim 3, further comprising: an off notification means for notifying and outputting the power-off held by said status holding means together with the identification data of said communication terminal apparatus. 5. A reply transmitting means for transmitting reply data to the communication terminal device to which the notification data has been received by the status receiving means.
The communication control device according to any one of the preceding claims. 6. A data communication system comprising: the communication terminal device according to claim 1; and the communication control device according to claim 3 or 4. 7. A data communication system comprising: the communication terminal device according to claim 2; and the communication control device according to claim 5.