JPH06177874A - Isdn data transmitter - Google Patents

Abstract

PURPOSE:To prevent increase of the communication cost of an ISDN data transmitter by providing a single channel communication function to transmit the picture information through a single B channel only and a 2-channel simultaneous communication function to transmit the picture information with simultaneous use of two channels. CONSTITUTION:An ISDN data transmitter consists of a facsimile image processor 1, a G4 communication processing part 2, the 4B channel access parts 3 and 4, a D channel transmission control part 5, an ISDN interface part 6, an operation display part 7, and a control part 8. Then the communication charge is calculated for two B channels when a fixed quantity of data is transmitted through the two channels together with the communication charge required for a single channel when the data is transmitted through a single channel. When the former charge is larger than the latter one, the information is transmitted through a single B channel only. Then two B channels are used in other cases.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ISDN data transmission device having a function of transmitting a fixed amount of data by simultaneously using two B channels.

[0002]

2. Description of the Related Art One ISDN basic line is provided with two B channels for information transmission. These two channels can be simultaneously used by one terminal device. Therefore, when a large amount of data is transmitted in a short time, communication using two channels at the same time is performed.

The CCITT recommendation defines the specifications for forming the above-mentioned two-channel communication link in one call connection procedure. However, in the current ISDN of each country,
The communication function conforming to that specification is not yet supported and cannot be used by the user.

For this reason, when the above-described two-channel communication is executed, the call connection procedure is executed twice between the terminal devices to form two B-channel communication links.

By the way, when data is transmitted by two channels, the communication time is reduced to 1/2. On the other hand, in the ISDN circuit switching service, a communication fee is charged for each channel by a fixed fee at regular intervals.

Therefore, even if data is transmitted by one channel,
For example, if communication is completed within a fixed time of the charging unit,
If data is transmitted using two channels, the communication fee will be doubled.

[0007]

However, the conventional data transmission device for transmitting data by 2 channels of B channel always transmits data by 2 channels.
Therefore, depending on the case, there is a problem that the communication cost becomes higher than that of data transmission by one channel.

An object of the present invention is to provide an ISDN data transmission device which solves the above problems and can prevent an increase in communication cost.

[0009]

To this end, the present invention provides a fixed amount of data to be transmitted before starting data transmission.
The communication charges for the two channels for transmitting the B channels and the two channels and the communication charges for the one channel for transmitting the one channel are calculated, and the communication charges for the two channels are transmitted for the one channel. When the price is higher than the charge, the data is transmitted only by the B channel 1 channel, and in other cases, the data is transmitted by the B channel 2 channel.

[0010]

This makes it possible to prevent an increase in communication cost.

[0011]

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 is a block diagram of a facsimile apparatus according to an embodiment of the present invention. In the figure, the facsimile image processing unit 1 compresses image information obtained by reading a document image during image transmission, and restores received image data to original image information during reception. An image is recorded on recording paper. The G4 communication processing unit 2 executes a G4 facsimile transmission control procedure. The B channel access units 3 and 4 have I
A data signal is transmitted / received to / from the B channel of SDN. The D-channel transmission control unit 5 transmits / receives a data signal to / from the D-channel and executes a call connection procedure at the time of originating / receiving a call. The ISDN interface unit 6
It is connected to the ISDN via a network terminating device (not shown) and transmits / receives signals to / from the ISDN.

The operation display section 7 displays the operating state of the apparatus while the operator performs various operations. The control unit 8 is a microcomputer that monitors and controls each of the above units.

Next, the communication operation between the facsimile apparatuses of the present embodiment having the above-mentioned configuration will be described.

FIG. 2 shows the transmission processing of this facsimile apparatus. That is, when transmitting a document, the operator on the transmission side sets the transmission document on the apparatus, sets the transmission destination, and activates it. When the facsimile apparatus is activated, the original image is read and the image information is stored (process 10).
1).

The facsimile apparatus according to this embodiment has a one-channel communication function for transmitting image information on only one B-channel and a two-channel communication function for transmitting image information by simultaneously using two channels.

When the image information is accumulated, the communication time required for transmitting the accumulated image information by one-channel communication,
The communication time required for transmission by two-channel communication is calculated. The communication time of 1-channel communication is calculated, for example, by dividing the data amount of image information by the data transmission speed,
The communication time of the two-channel communication is 1/2 of that.

Further, a communication charge for transmitting image information by one-channel communication and a communication charge for transmitting image information by two-channel communication are calculated. That is, the facsimile apparatus according to the present embodiment stores in advance the billing information indicating how many seconds and how much the ISDN line fee is charged for each B channel when communicating with each destination. Based on this billing information and the communication time, each communication charge is calculated (above, process 102).

Then, it is determined which of the one-channel communication and the two-channel communication is advantageous. In this case, if the communication charges are the same for 1-channel communication and 2-channel communication, 2
The channel communication is determined to be advantageous because the channel communication can be performed in a short time. On the other hand, when the communication charge for the two-channel communication is higher, it is determined that the one-channel communication is advantageous because the communication cost is low (process 103).

When it is determined that the two-channel communication is advantageous (Y in process 103), it is determined whether the B channel is free of two channels (process 104). Since a plurality of terminal devices can be connected to one line in ISDN, the B channel may already be used because another terminal device is communicating.

If both B channels are vacant (Y in processing 104), the call connection procedure with the transmission destination is executed twice to form a communication link of B channels and 2 channels (processing 105). ). Then, the transmission of the accumulated image information is started (process 106).

Thereafter, the rest of the image information is checked (process 107), and when the image information to be transmitted remains (N in process 107), the line quality of the B channel is determined. That is, in the data transmission of the image information being executed, the frequency of the retransmission process is compared between the two B channels. If the frequency of retransmission processing is extremely high in one channel, it is determined that the channel quality of that channel is defective (processing 108).

Next, the communication time required for transmitting the remaining image information is calculated. In addition, the remaining image information is 2 as it is.
The communication charge required when transmitting by channel communication and the communication charge required when transmitting by switching to one-channel communication are calculated (process 109).

Then, it is determined which of two-channel communication and one-channel transmission is advantageous. In this case, the determination result of the line quality is considered together with the determination of the process 103. That is, if there is no poor line quality and the communication charges for the two-channel communication and the one-channel communication are the same, it is determined that the two-channel communication is advantageous. In this case (Y of processing 110),
The above operation is repeated as it is (process 107).

If the channel quality of one channel is poor, or if the communication charge for two-channel communication is high, it is determined that one-channel communication is advantageous. In this case (N in process 110), the call disconnection procedure is executed for one B channel. That is, if the channel quality of one channel is poor, the call is disconnected for that channel. Also, if there is no difference in channel quality between the two channels, the call is disconnected for any one channel (process 111). After that, the above operation is repeated while the image information transmission operation is being performed on the other one channel (process 107).

In this way, when the transmission of the image information is completed (Y in step 107), the B channel and the channel 2 are also disconnected and the communication is ended (step 112).

On the other hand, in the judgment at the time of starting the communication, 1
When it is determined that the channel communication is advantageous (N in process 103), the call connection procedure is executed once to form the communication link of B channel and 1 channel (process 113). Then, the transmission of the image information is started (process 114).

After that, the remaining image information is checked (process 115), and when the image information remains (N in process 115), the communication time required to transmit the remaining image information is set in the same manner as described above. The communication charges for the one-channel communication and the two-channel communication are calculated (process 116).

Then, which of the two-channel communication and the one-channel transmission is more advantageous is determined in the same manner as the above-mentioned processing 103 (processing 117). Here, when the one-channel communication is advantageous (N in process 117), the above operation is repeated as it is (to process 115).

In this way, when the transmission of the image information is completed (Y in process 115), the call is disconnected and the communication is completed (process 112).

On the other hand, when it is determined that the two-channel communication is advantageous (Y in processing 117), it is determined whether or not the other B channel is available (processing 118). If the other B channel is free (Y in operation 118), the call connection procedure is executed here to form the communication link of the B channel (operation 119). Then start 2 channel communication,
The operation shifts to the two-channel communication operation (process 107).
What).

Even if it is determined that the two-channel communication is advantageous, if the other B channel is not available (process 118).
N), 1-channel communication is continued (to process 115).

As described above, in the present embodiment, when transmitting the image information, the communication charges for the case of transmitting by the B channel 2 channels and the case of transmitting by the 1 channel are calculated and transmitted by the 2 channel. When the communication charge in the case of performing is higher than that of the case of one channel, the B channel is transmitted only by one channel.

This makes it possible to prevent an increase in communication cost. Further, when the communication charges in the above two cases are the same, the communication time can be shortened because the transmission is performed in two channels.

Further, even if the communication charge is cheaper by transmitting in two channels, but if the B channel is not free in two channels, the communication is started in one channel.
Image transmission can be executed even while another terminal device on the same line is communicating.

After starting the one-channel communication, the communication charge for transmitting the remaining image information is calculated, and the two-channel communication is more advantageous. It is designed to switch to 2-channel communication.

As a result, even when one-channel communication is started because two B-channels are not available,
It is possible to shift to advantageous 2-channel communication from the middle. Further, when the retransmission process of data transmission occurs after the start of the transmission of the image information, the actual communication time becomes longer than the communication time calculated before the start of the communication, and thus the two-channel communication may be more advantageous. Also in this case, since the mode is shifted to the two-channel communication, the image information can be transmitted under a more advantageous condition.

Further, even if the two-channel communication is started, if the retransmission process of the data transmission frequently occurs in one channel, the call is disconnected to the one channel and the communication is shifted to the one-channel communication, so that the communication fee increases. Can be prevented.

In the above embodiments, the case where the image information is transmitted by the facsimile device has been described as an example, but the present invention is not limited to the facsimile device and can be widely applied to various data transmission devices of ISDN. Nor.

[0040]

As described above, according to the present invention, the communication charge for data transmission in two channels of B channel and the communication charge for data transmission in one channel are calculated and transmitted in two channels. In this case, if the communication charge is higher than that for one channel, data transmission is performed on only one channel, and data transmission is performed on two channels in other cases, thus preventing an increase in communication cost. Will be able to.

[Brief description of drawings]

FIG. 1 is a block configuration diagram of a facsimile apparatus according to an embodiment of the present invention.

FIG. 2 is an operation flowchart showing a transmission process of a facsimile device.

[Explanation of symbols]

 1 Facsimile image processing unit 2 G4 communication processing unit 3, 4 B channel access unit 5 D channel transmission control unit 6 ISDN interface unit 7 Operation display unit 8 Control unit

Claims (3)

[Claims] 1. An ISDN data transmission device having a function of transmitting a fixed amount of data by simultaneously using B channels and 2 channels, wherein the fixed amount of data is used by B channels and 2 channels before data transmission is started. A communication charge calculating unit for calculating a communication charge for two channels for transmission and a communication charge for one channel for transmission using only one channel, and the communication charge for the two channels is for the one channel. If the communication charge for one channel is higher than the communication charge for one channel, the one-channel communication execution means for transmitting data using only one channel is used, and if the communication charge for the two channels is equal to or less than the communication charge for the one channel, the above An ISDN data transmission device comprising: two-channel communication execution means for performing data using two channels. 2. An ISDN data transmission device having a function of transmitting a fixed amount of data by using two B channels at the same time, when only one B channel is vacant when executing data transmission. 1-channel communication starting means for starting data transmission using only 1 channel, and a communication charge for 1 channel required when transmitting the remaining data using only 1 channel of B channel after starting the data transmission The communication charge calculating means for calculating the communication charges for the two channels when transmitting using two channels, the detecting means for detecting the vacancy of the other B channel, and the above-mentioned 2 calculated when the other B channel becomes vacant. If the communication charge for one channel is lower than the communication charge for one channel above, the other B channel is also used to transmit data on two channels. And an ISDN data transmission device, comprising: 3. In an ISDN data transmission device having a function of transmitting a fixed amount of data by simultaneously using B channels and 2 channels, one channel is switched to the other after starting data transmission using B channels and 2 channels. In comparison, the ISDN data transmission device is provided with a 1-channel releasing means for stopping the use of only one channel when the frequency of retransmission processing is high and the line quality is poor.