JPH0888695A - Data transmission method - Google Patents

Abstract

PURPOSE: To improve the data transmission efficiency in the case of sending data via a public line by having plural channels and selecting any of the plural channels. CONSTITUTION: In the data transmission method having plural channels, selecting any of the plural channels and sending data via a public line 3, the normality of the selected channel is discriminated based on the presence of a dial tone before dial processing. When the selected channel is discriminated to be faulty, the channel is separated to invalidate it, then the normality of the channel is discriminated early and the channel discriminated to be faulty is not selected for succeeding transmission processing and useless time of channel connection in data transmission is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data transmitting method for transmitting data using a public line, and more particularly to a data transmitting method for detecting normality / abnormality of a channel used at an early stage to improve transmission efficiency. Is.

[0002]

2. Description of the Related Art When data is transmitted through a public line with a plurality of channels, it is judged whether or not the channels to be used are normally connected, and if they are normal, the data transmission process is started.

First, the system configuration of data transmission will be described with reference to FIG.

Reference numeral 1 is a distribution device, 2a, 2b, 2c ... are transmission side modems, 3 is a public line, 4a, 4b ... are terminal side modems.

The digital signal emitted from the distribution apparatus 1 is one of the transmission side modems 2a, 2b, 2c ...
Is converted into a voice signal, and further transmitted via the public line 3 to a terminal device selected among the terminal devices 5a, 5b ..., After the voice signal is converted into a digital signal by the modem of the terminal device, It is received by the terminal device.

The distribution device 1 has a plurality of channels, and further, a CPU automatically calls and connects to a plurality of terminal devices 5.

The distribution device 1 will be described with reference to FIG.

In the figure, 6 is a main control section, 7 is a communication control means,
8 is a storage unit for storing untransmitted data, 9 is data called from the storage unit 8 for transmission, 10 is CH1, CH
Channel status storage units for storing channel statuses of 2, CH3 ..., 11, 12, 13 ... Represent CH1 transmitting means, CH2 transmitting means, CH3 transmitting means, respectively.

The main control unit 6 selects an available channel in the channel status storage unit 10 via the communication control unit 7, and the CH1 transmission unit 11, C.
Of the H2 transmitting means 12, the CH3 transmitting means 13, ..., the selected transmitting means and the CH1 transmitting means 11 can be used.

The data 9 to be transmitted from the storage unit 8 is called, the data 9 is output to the CH1 transmitting means 11, and the CH1 transmitting means 11 outputs it to the public line 3 via the corresponding transmitting modem 2a. To do.

Next, a conventional data transmission method will be described with reference to FIG.

When data transmission is started, an on-hook process is performed and a dial process is immediately performed. Whether or not there is a response from the modem is confirmed, and when the response from the modem is confirmed, connection processing with the terminal device 5 is performed. When normally connected to the terminal device 5, data transmission processing is performed,
When the transmission process is completed, the on-hook process is performed and the series of data transmission is completed.

If the terminal device 5 cannot be connected to the terminal device 5 due to a channel error, a busy state, no response, etc., after the on-hook process, the connection process is repeatedly performed a set number of times, and the terminal device 5 is connected. When the connection is established, the untransmitted data is set and the data transmission process is performed. When the transmission process is finished as described above, the on-hook process is performed and the series of data transmission is completed.

When the connection process is repeatedly performed the set number of times and the connection with the terminal device 5 cannot be established, the process of changing to another transmission channel is performed, and the on-hook process and the above-mentioned line connection and data connection process are performed again. Is repeated.

During this time, it took about 15 to 40 seconds to determine whether the connection was successful or failed, as shown in FIG.

[0016]

As described above, conventionally, the dial processing is performed immediately after the on-hook processing, and it is determined whether the channel being used is normal or not from the result of whether the line is connected or not. If the connection fails, the channel is switched to another channel and the retransmission process to the same destination is repeated.

Therefore, even if an abnormal channel exists, that channel may be reused.
In addition, it takes a long time to detect when there is an abnormal channel such as not being connected to a public line, and therefore the wasteful time until the connection is increased and the efficiency of data transmission is reduced.

In view of the above situation, the present invention aims to improve the transmission efficiency by making it possible to immediately determine the detection of an abnormal channel.

[0019]

According to the present invention, there is provided a data transmission method comprising a plurality of channels, selecting any one of the plurality of channels, and transmitting the data via a public line. According to a data transmission method, which is characterized by determining whether a channel is normal or abnormal by the presence or absence of a dial tone before dial processing, and when the selected channel is determined to be abnormal, the channel is disconnected and the data becomes unusable. It relates to the transmission method.

[0020]

[Function] Since the normality / abnormality of the selected channel is determined by the presence / absence of the dial tone before the dial processing, the normality / abnormality of the channel can be determined at an early stage. In the next transmission process, the channel determined to be abnormal is not selected, and the wasteful time until the line connection for data transmission is shortened.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a flow chart of data transmission of the present invention. The hardware constituting the present invention is the same as that shown in FIGS.

When the transmission process is started, the communication control means 7
Confirms the state of each channel in the channel status storage unit 10. If all channels are unavailable,
The transmission process is stopped. Further, the confirmation result of the state of each channel is fed back to the main control unit 6, and the result is displayed on the display unit if necessary.

When the communication control means 7 determines that all the channels are not available, the available channels are searched and the used channels are determined. The data transmission process is further continued using the determined channel.

The on-hook processing is performed and the dial tone is confirmed. If the dial tone is confirmed, it means that the channel and the public line are normally connected, and the dial process is continued. On the other hand, when the dial tone is not confirmed, it means that the selected channel and the public line are not normally connected, and the result is fed back to the communication control means 7 to select the selected channel. Disable the channel status of. Further, the communication control means 7 searches for a usable channel, and if there is a usable channel, the dial tone of the channel is confirmed. If the dial tone is confirmed, the dial process is continued as described above.

Whether or not there is a response from the modem is confirmed, and when the response from the modem is confirmed, connection processing with the terminal device 5 is performed. When the terminal device 5 is normally connected, a data transmission process is performed, and when the transmission process ends, an on-hook process is performed, and a series of data transmission is completed.

If the terminal device 5 cannot be connected to the terminal device 5 due to a channel error, a busy state, no response, etc., after the on-hook process is performed, the connection process is repeated by the set number of times, and the terminal device 5 is tried. If the connection is established, untransmitted data is set and data transmission processing is performed. When the transmission processing ends, on-hook processing is performed and a series of data transmission is completed, as described above.

When the connection process is repeated by the set number of times and the connection with the terminal device 5 cannot be established, the process of changing to another transmission channel is performed and the line connection and data connection described above are resumed from the on-hook process. The process is repeated.

As described above, according to the present invention, the channel abnormality is discriminated at the stage of the on-hook processing, and when the channel abnormality is discriminated, the channel is switched without dial processing and the channel which is discriminated as abnormal is made unusable thereafter. Disconnect from the transmission processing target channel of.

Therefore, in the present invention, as shown in FIG. 2, the channel abnormality is determined in about 2 to 3 seconds.

It is needless to say that the present invention can be implemented in all data transmission devices that transmit data using a public line.

[0032]

As described above, according to the present invention, a channel abnormality can be detected at an early stage, and a channel judged to be abnormal is prevented from being used in the subsequent data transmission processing. It is possible to greatly reduce the wasteful time until it is performed, and it is possible to significantly improve the transmission efficiency.

[Brief description of drawings]

FIG. 1 is a flowchart showing an embodiment of the present invention.

FIG. 2 is a timing chart of an example of the present invention.

FIG. 3 is a system configuration diagram of a data transmission method.

FIG. 4 is a block diagram of a distribution device.

FIG. 5 is a flowchart showing a conventional example.

FIG. 6 is a timing chart of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 distribution apparatus 2 transmission side modem 3 public line 4 terminal side modem 5 terminal apparatus 6 main control section 7 communication control section 8 storage section 9 data 10 channel status storage section 11 CH1 transmission section 12 CH2 transmission section 13 CH3 transmission section

Claims (2)

[Claims] 1. A data transmission method comprising a plurality of channels, selecting any one of the plurality of channels, and transmitting data via a public line, a dial process for normality / abnormality of the selected channel. A data transmission method characterized by determining whether or not there is a previous dial tone. 2. When the selected channel is determined to be abnormal, the channel is disconnected and disabled.
Data transmission method.