JPS59205869A - Remote supervisory control system of communication - Google Patents

Abstract

PURPOSE:To release a line by a called party side (receiving side) itself when a received data amount is larger than a prescribed value by providing a means counting a data amount of a data transmitted from a caller side to the called party side. CONSTITUTION:A picture signal received via a line 9 and a line control section 1 is demodulated by an MODEM2 and stored in a transmitting/receiving buffer 31 as a received picture data. A control section 30 transmits a receiving command to a picture processing section 6. Then, the processing section 6 decodes a received picture data stored in the buffer 31 and a recording section 8 reproduces a picture. On the other hand, a counter 5 counts a data bit number when a picture data of the buffer 31 is transmitted to the picture signal processing section 6. This count output is applied to a comparator 4. The comparator 4 compares the set value with the counter output and when the counter output exceeds the set value, it is taken as an abnormal state and an anomalous detecting signal ALM commanding the disconnection of line is outputted to the line control section 1. Further, the signal ALM is given also to the control section 30.

Description

[Detailed Description of the Invention] jal Technical Field of the Invention The present invention relates to a communication monitoring and control system, and in particular, the present invention relates to a communication monitoring and control system, in particular when a line established for data communication is held unnecessarily due to the occurrence of field lightning on the transmitting and receiving sides during data communication. Regarding the method of monitoring the continuation.

(bl Technology background) For example, in the field of facsimile, facsimile data is communicated using switched telephone lines such as subscriber telephone lines. Facsimile is used in a completely automatic form of communication that requires no human intervention on both the sender's side (callee) and the sender's side (callee's side).

The problem here is that due to an abnormality that occurs in the transmitting and receiving terminal devices during data communication, it is possible that the telephone circuit continues to be held even though communication is disabled. This unnecessary holding state of the communication line leads to the addition and accumulation of line charges (telephone charges), resulting in no great loss to the communication terminal user.

(C1 Prior Art and Problems Taking facsimile communication as an example, first, the called terminal device, which is to be the destination of facsimile communication, is called by a dial signal etc. from the calling side QW1 not installed. As a result, the calling side and the called terminal device are called. The calling side line is established. After the line is established, command signals and response signals are exchanged between the calling side and the called side according to a predetermined control procedure.
The next step is to transmit the image signal).

This image signal transmission method uses a predetermined block length (
For example, there is a method in which image signal transmission and reception is confirmed between the calling side and the called side every few lines of a document, and a method in which confirmation is made every time transmission of a transmitted document page is completed for high-speed communication. Particularly in the latter case, if there is no end signal from the calling side indicating the end of transmission of the document-page image signal, the communication state between the two terminals remains, resulting in a permanent line holding state.

In order to prevent such failures, conventionally, a maximum time length required for transmitting an image signal for one page of a document is set in advance, and if the image signal is being transmitted for longer than this maximum time length, the line is released. A method was adopted to do so. However, setting this time length depends on the transmission speed of the image signal (for example, 9600 bps).
, 2,400 bps, etc.), it was necessary to match the maximum time table required in the case of low-speed transmission. Therefore, when performing higher-speed transmission, there is a drawback that a large loss occurs in this setting time.

(d) Purpose of the Invention The purpose of the present invention is to provide a communication monitoring and control method that can efficiently detect abnormal conditions during communication, regardless of the image signal transmission speed, in order to eliminate the above-mentioned conventional drawbacks. .

(e) Structure of the Invention In order to achieve the above object, the present invention provides means for counting the amount of data received from the transmitting side (calling side) on the receiving side (called side), and calculates the amount of data in units of data. If the amount of data received until a signal indicating the end of transmission is received exceeds a predetermined value, the receiving side itself releases the line.

The present invention will be described in detail below based on Examples.

(f) Embodiment of the invention FIG. 1 is a diagram illustrating a transmission procedure between a calling side and a called side in facsimile communication, and FIG. 2 is an example of an embodiment in which the present invention is applied to a facsimile terminal device. FIG. 2 is a block diagram illustrating an example.

First, the calling side terminal device sends out a connection signal SSt for connecting a line with the destination (called side) terminal to which the image signal is to be sent. When the called side receives this signal SS/, it sends a response signal R3/ to notify the receiving function of its own device (for example, transmission speed, type of compression method that can be decoded, etc.) if its own device is in a receivable state. to be sent back. Next, the rules for exchanging image signals between the two terminals (transmission speed, encoding/decoding method, etc.) are confirmed by the command signal SS'2-2 from the calling side and the response signal R82 from the called side. . After this confirmation is completed, the image signal DATA will be sent from the calling side.

In this embodiment, this image signal DATA is sent to one original document (-
Page) does not indicate when to give or receive. I″i1st from the calling side (
When the transmission of the image signal DATA (page 1) is completed, an end signal C33 indicating the end of the transmission is issued. Upon receiving this end signal SSj, the called side receives the image signal DAT of the unit concerned.
A response signal R37 is issued to notify the reception state of A. The calling side learns the reception status of the called side from this response signal R83, and if it is received normally, it will send out the next image signal. Also, when the transmitted image signal ends,
This occurs every time the transmission end signal SSq is issued.

In this embodiment, during the above transmission procedure, when the image signal transmission/reception processing begins, both the calling side and the called side start counting the image data. That is, the calling side counts the amount of transmitted data from time A when transmission of the image signal starts. On the other hand, the called side counts the amount of received image data from time point B when the image signal is received. In other words, both the calling and called parties count the data amount (for example, the number of bits) for each page, and if it reaches a preset value (-maximum data amount of page N bits), it is considered as abnormal.
Disconnect the line and return to the initial state.

In this case, it goes without saying that the amount of data for each page in normal image signal communication is always less than N bits.

The operation of the embodiment shown in FIG. 2 will be explained below.

M indicates a facsimile transmitting/receiving device capable of transmitting and receiving image signals; 1 is a line control unit (NCU), 2 is a modem (M), 3 is a transmission control unit, 4 is a comparator, 5 is a counter, Reference numeral 6 denotes an image signal processing unit, 7 a reading diagram of a transmitted original image, and 8 a recording unit of received image data.

9 indicates a public line. The transmission control unit 3 also includes a control unit 3 that transmits and receives control signals before transmitting both of the signals described above.
0. and a buffer 31 in which image signals for transmission or reception are temporarily stored.

Thus, when the embodiment apparatus operates as a calling side, first, under the control of the control unit 30, the line control unit 1 sends out a line connection request signal with the called side onto the line 9. As described above, the control unit 30 then performs preprocessing for image signal transmission based on the response signal from the called side.

Now, at time A shown in FIG. 1, that is, when starting the image signal sending process, first, the image on the inserted transmission document is read by the reading section 7. The read data from the reading section 7 is encoded as image data by the image signal processing section 6.

The encoded image data is stored in the buffer 31 for each line of the read image, for example. While this image data is stored in the buffer 31, the counter 5 counts the number of focuses of the image data. That is, the contents of the counter 5 are cleared by the clear signal CL from the control section 30 at the same time as the image signal starts. This clear signal is outputted by the reading section 1 every time reading of a document page is completed. Thereafter, the number of bits of the output encoded data from the image signal processing section 6 to the buffer 31 is counted by the counter 5.

At the same time, the control unit 30 enables the comparator 4 using the drive signal EN. The comparator 4 is separately given the above-mentioned set value (N bits in this case). When the comparator 4 determines that the output value of the counter 5 (that is, the data M of the transmitted image signal) is larger than the set value N, a detection signal ALM is output. This detection signal ALM is supplied to the line control section 1 and the control section 3o. As a result, the line control unit 1 opens the line 9 with the called party. Also, the control section 30
is the image signal processing section 6. The reading section 7 issued a helicentization issue,
Return the device to its initial state.

When the apparatus operates normally, the image signal processing section 6 issues an end signal NEN indicating the end of the image data processing (that is, the reading of all the transmitted originals has been completed). This signal NEN
The line will be automatically released.

Next, a case will be described in which the device shown in FIG. 2 operates as a called party. The connection signal and control signal from the calling side are received by the control unit 30 via the line control unit 1 and modem 2,
A response signal is issued from this control section 30 through a similar route. Since the specific control procedure has already been described, it will be omitted here.

When the called terminal device moves to image signal reception processing (time point B in FIG. 1), the control section 30 resets the counter 5 with the signal CL and activates the comparator 4 with the signal EN. Thereafter, the image signal received via the line 9 and the line control section 1 is demodulated by the modem 2 and stored in the transmission/reception buffer 31 as received image data. The control section 30 sends a reception command to the image processing section 6. Then, the processing unit 6 decodes the received image data stored in the buffer 31,
The recording unit 8 will reproduce the image.

On the other hand, the counter 5 counts the number of data bits when the image data in the buffer 31 is sent to the image signal processing section 6. This count output is supplied to a comparator 4. Comparator 4
Then, the set value N bits and the counter output are compared, and when the counter output exceeds N bits, it is determined that an abnormal state is reached and an abnormality detection signal ALM is outputted to the line control section 1 to instruct disconnection of the line.

Furthermore, as described above, this signal ALM is given to the control section 30. That is, in a normal case, the end signal (S3 in FIG. 1) is sent from the calling side 11 at the end of sending out the image signal for each page of the original. This end signal is detected by the control section 30 of the transmission control section 3, and upon this detection, the control section 30 outputs a clear signal CL to reset the counter 5. Therefore, the termination signal is correctly issued by the calling side,
If the called side is receiving correctly, this comparator 4
The output ALM is not output. Further, when an image signal transmission completion signal is received from the calling side, after the recording of the final image data is completed by the image signal processing section under the control of the control section 30, the line 9 is automatically switched off by the completion signal NEN. will be opened to the public.

As described above, according to this embodiment, the completion signal N F is issued by the transmission control section 3 and the processing section 6.

Since a means for detecting communication abnormalities is provided completely independently of N, communication failures caused by malfunctions of these transmission control units 3 to processing units 6, etc. can be immediately detected, and unnecessary holding states of the line 9 can be prevented. You can cancel it immediately. In particular, providing this means on the called side is useful if the control signal received from the calling side via the line cannot be correctly identified on the called side due to sudden changes in line characteristics, etc. However, it has great practical value in that it can prevent unnecessary line connections.

(g+ Effects of the Invention As detailed above, according to the present invention, it is possible to immediately avoid an unnecessary line establishment state caused by an abnormality in the equipment. Especially in a completely unmanned facsimile communication system, users are forced to pay illegal line charges. The effect is a helper.

[Brief explanation of the drawing]

FIG. 2 is a process diagram showing an embodiment applied to a remote terminal device. 1 is a line control section, 2 is a modem, 3 is a striped transmission control section, 4 is a comparator, 5 is a call destination, and 6 is an image signal processing section. Agent Patent Attorney Censor Koshibe 1 1, -・Co・Il et al. 3:), -l

Claims (1)

[Claims] In a data communication system in which a response signal in response to the termination signal is sent back from the receiving side, the receiving side receives the termination signal via the line before receiving the termination signal. The method is characterized in that a means for counting the amount of data that has been sent is provided, and the line established with the transmitting side is opened according to the amount of data counted by the counting means until the end signal is received. (2) The data sent from the sending side is facsimile data obtained by reading the transmitted original, and the end signal is transmitted every time facsimile data transmission for each page of the transmitted original is completed. A communication monitoring control system according to claim (1).