JP2002111954A - Facsimile system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a facsimile system for realizing a real time Internet facsimile communication at high speed without inconvenience like a waiting time generated by use of the Internet and the like. SOLUTION: When image data is sent from a facsimile system 1 to a facsimile system 7, a pre-procedure and a procedure of modem training with TCF signal are carried out independently and asynchronously between the facsimile system 1 and a gate way system 3, and between a gate way system 5 and the facsimile system 7. A re-transmission request from the facsimile system 7 is received and re-transmitted by the gate way system 5. Meantime, the sending-side facsimile system 1 has a waiting time, so the flow control is carried out by using RNR signal or RR signal to cause the facsimile system 1 to wait.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a facsimile system capable of real-time facsimile communication using the Internet.

[0002]

2. Description of the Related Art Conventionally, facsimile communication has been performed between a facsimile apparatus connected via a public line or a dedicated line. 30 and the like. In recent years, the Internet has been used as a part of a communication path to reduce long-distance call charges.

In the conventional facsimile communication using the Internet, for example, transmission of a facsimile image as mail has been considered. Recently, a real-time Internet facsimile system for transmitting a facsimile image in real time has been developed. .

FIG. 3 is an explanatory diagram of an example of a configuration of a conventional real-time Internet facsimile system. In the figure, reference numerals 1 and 7 denote facsimile machines, 2 and 6 denote public lines or extensions, 3 and 5 denote gateway devices, and 4 denotes the Internet. For example, when transmitting a facsimile image from the facsimile apparatus 1 to the facsimile apparatus 7 in real time using the Internet 4, the facsimile apparatus 1 first includes a public line or an extension 2 (including a dedicated line or the like).
The same applies to the following). Communication between the facsimile apparatus 1 and the gateway apparatus 3 is based on T.30. A facsimile communication protocol such as 30 is used. The gateway device 3 communicates with the gateway device 5 through the Internet 4. The communication at this time is based on T. A real-time internet facsimile protocol such as 38 is used. Further, the gateway device 5 calls the facsimile device 7 through the public line or the extension 6, and connects to the facsimile device 7. Communication between the gateway device 5 and the facsimile device 7 is based on T.30. A facsimile communication protocol such as 30 is used.

[0005] In this manner, the communication path from the facsimile machine 1 to the facsimile machine 7 is connected. Then, facsimile communication is performed in accordance with the protocol between the respective devices, and the facsimile image transmitted from the facsimile device 1 is transmitted to the gateway device 3 and the gateway device 5.
Is transmitted to the facsimile machine 7 in real time.

As described above, in real-time Internet facsimile communication, the gateway devices 3 and 5
Communication is performed with the facsimile apparatuses 1 and 7 via public lines or extensions 2 and 6 according to a facsimile communication protocol. In the facsimile communication protocol,
A procedure for returning a response signal to a signal transmitted from one side is often used. For example, after sending image data,
Return the F signal. After confirming such a response signal, the operation shifts to the transmission and reception of the next signal. By exchanging such procedure signals, the facsimile apparatus 1 and the facsimile apparatus 7 perform communication while maintaining synchronization.

However, as shown in FIG. 3, since the facsimile machine 1 and the facsimile machine 7 pass through the Internet, data may be delayed. When such a delay occurs, a signal to be received does not arrive within a predetermined time, so that a communication error occurs, or retransmission is performed, and a plurality of same signals arrive.

[0008] Further, when ECM communication is performed, retransmission can be requested when an error is detected in the facsimile apparatus on the receiving side. At this time, even if the image data exists in the gateway device on the receiving side, the retransmission request is transmitted to the facsimile device on the transmitting side, and the image data is retransmitted. As a result, the communication speed has decreased and the traffic volume on the Internet has increased.

Further, for example, when a sequence such as training is executed, signals are exchanged between the facsimile machines on the transmitting side and the receiving side. However, in practice, it is sufficient to execute training from the receiving-side gateway apparatus to the receiving-side facsimile apparatus and return the result to the transmitting-side facsimile apparatus, thus performing useless communication. The same applies to the processing at the time of transmission and reception.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and it is possible to satisfactorily perform real-time Internet facsimile communication without inconvenience caused by waiting caused by use of the Internet. It is another object of the present invention to provide a facsimile system in which real-time Internet facsimile communication is speeded up.

[0011]

SUMMARY OF THE INVENTION The present invention relates to a facsimile system capable of real-time facsimile communication from a facsimile apparatus to another facsimile apparatus using the Internet via a gateway apparatus.
When a wait occurs between the gateway device and the facsimile device during M communication, flow control is performed using an RNR signal and an RR signal. This R
The flow control based on the NR signal and the RR signal is configured to retransmit the image data from the gateway device on the receiving side when a retransmission is requested by the facsimile device on the receiving side, for example.
By this retransmission, it is possible to perform flow control of a waiting time generated between the facsimile machine on the transmitting side and the gateway apparatus on the transmitting side. Further, for example, after the image data transmitted from the facsimile apparatus is transferred via the Internet, the flow control of the waiting time until the response signal is returned from the receiving side can be performed by the RNR signal and the RR signal.

In this way, the waiting time caused by the delay due to the Internet, the waiting time during retransmission of image data on the receiving side, and the like are determined by the RNR signal between the facsimile apparatus on the transmitting side and the gateway apparatus. And R
Communication can be continued by the flow control using the R signal. As a result, the inconvenience due to the occurrence of the waiting time does not occur, and the real-time Internet facsimile communication can be favorably performed.

Further, as described above, the image data is retransmitted between the gateway device on the receiving side and the facsimile device, so that the image data need not be transmitted again from the facsimile device on the transmitting side as in the prior art. Thus, high-speed communication can be performed by shortening the communication time. In addition, the traffic volume on the Internet can be suppressed.

The present invention further provides a facsimile system capable of real-time facsimile communication from a receiving-side facsimile apparatus to a receiving-side facsimile apparatus using the Internet from a transmitting-side facsimile apparatus via a transmitting-side gateway apparatus. It is characterized in that the communication between the facsimile machine on the transmission side and the gateway apparatus on the transmission side and the communication between the facsimile apparatus on the reception side and the gateway apparatus on the reception side are executed asynchronously. For example, by performing procedures such as outgoing and incoming calls, training, and the above-described retransmission processing asynchronously between the transmitting side and the receiving side, the time required for communication is reduced, and high-speed real-time Internet facsimile communication is performed. be able to.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an explanatory diagram showing an example of a configuration and a communication sequence showing an embodiment of a facsimile system of the present invention. The reference numerals in the figure are the same as those in FIG.
Here, description will be made assuming that image data is transmitted from the facsimile apparatus 1 to the facsimile apparatus 7 in real time via Internet facsimile. Also, communication is performed in the ECM mode.

First, a call is sent from the facsimile machine 1 to the gateway device 3 on the transmitting side using the public line or the extension 2, and when the call is received by the gateway device 3, the gateway device 3 sends the destination ( The gateway device 5 on the receiving side is specified from the telephone number of the facsimile device 7) and the like, and the calling of the facsimile device 7 is instructed via the Internet 4. The gateway device 5 calls the facsimile device 7 using the public line or the extension 6, and if the facsimile device 7 connects the line in response thereto, real-time Internet facsimile communication between the facsimile device 1 and the facsimile device 7 is performed. Will be possible.

After the line is connected, various pre-procedures are executed. At this time, the pre-procedure up to the first FSK frame after the transmission / reception is asynchronous between the facsimile apparatus 1 on the transmitting side and the gateway apparatus 3 and between the gateway apparatus 5 on the receiving side and the facsimile apparatus 7, respectively. To communicate. As a result, communication can be performed in a shorter time than when the respective procedure signals are transmitted and received between the facsimile machine 1 and the facsimile machine 7.
In addition, for example, a V.F. 34, V.34 between the facsimile apparatus on the other side and the gateway apparatus. It is also possible to use 17 or the like.

When the above-described pre-procedure is completed, a facsimile machine 7 on the receiving side transmits a DIS signal. This DIS signal includes information on the receiving facsimile machine 7 to be transmitted to the transmitting facsimile machine 1, such as the receiving capability of the receiving facsimile machine 7.
Therefore, the DIS signal transmitted from the facsimile machine 7 on the receiving side needs to be transmitted to the facsimile machine 1 on the transmitting side. Therefore, the DIS signal transmitted from the facsimile machine 7 on the receiving side is received by the gateway device 5 on the receiving side, and then transmitted to the gateway device 3 on the transmitting side via the Internet 4 to the facsimile machine 1 on the transmitting side. Sent.

The facsimile machine 1 on the transmitting side analyzes the received DIS signal to determine a communication mode, and
It is transmitted as a CS signal. The communication mode is notified to the facsimile machine 7 on the receiving side by this DCS signal so that the communication modes on the transmitting side and the receiving side match. Therefore, this D
The CS signal needs to reach the facsimile machine 7 on the receiving side. Therefore, after the DCS signal transmitted from the facsimile machine 1 on the transmitting side is received by the gateway apparatus 3 on the transmitting side, it is transmitted to the gateway apparatus 5 on the receiving side via the Internet 4 and transmitted to the facsimile apparatus 7 on the receiving side. Can be

After the transfer of the DCS signal, the training of the modem is performed by the TCF signal. However, the training of the modem is necessary between the facsimile machine 1 on the transmitting side and the gateway apparatus 3 and between the gateway apparatus 5 on the receiving side and the facsimile apparatus 7, and the training between the gateway apparatus 3 and the gateway apparatus 3 is required. Not required between 5 Therefore, the training of the modem may be performed independently between the facsimile machine 1 on the receiving side and the gateway apparatus 3 and between the gateway apparatus 5 on the receiving side and the facsimile apparatus 7. By independently and asynchronously training the modem on the transmitting side and the receiving side in this way, transmission and reception of the TCF signal can be performed without using the Internet 4, respectively.
Communication time can be reduced. Further, by independently and asynchronously training the modems on the transmitting side and the receiving side, respectively, the communication speed on the transmitting side and the communication speed on the receiving side can be set to optimal speeds. Further, since the transmitting side and the receiving side execute the training sequence independently, It is possible to cope with a procedure that does not use a TCF signal, such as 34.

As a result of the training, a CFR signal is returned from the gateway device 3 to the facsimile device 1 on the transmitting side and from the facsimile device 7 to the gateway device 5 on the receiving side.

When the training sequence is completed, the image data is transferred. The facsimile device 1 transmits image data to the gateway device 3, and the gateway device 3 transfers the image data to the gateway device 5 via the Internet 4. Then, the gateway device 5 transmits the image data to the facsimile device 7. If the image data is normally received by the facsimile machine 7, the facsimile machine 7 on the receiving side will transmit an MCF signal. However, the example shown in FIG. 1 shows a case where a reception error has occurred in the facsimile apparatus 7 on the receiving side and a retransmission is requested by the PPR signal.

In normal facsimile communication, since the facsimile apparatuses are connected one-to-one, retransmission cannot be performed unless image data is transmitted from the transmission source facsimile apparatus. However, in real-time Internet facsimile communication using the Internet 4, an error check is performed between the facsimile device 1 and the gateway device 3 on the transmitting side and also between the gateway device 3 and the gateway device 5. No error has occurred in the communication path up to the gateway device 5 when the image data is transmitted to the gateway 7. Therefore, when receiving a retransmission request from the facsimile machine 7 on the receiving side, the gateway apparatus 5 on the receiving side can respond. Therefore, the PPR that issues a retransmission request
The signal is received by the gateway device 5, and the gateway device 5 retransmits the image data. by this,
The image data need not be sent again from the facsimile machine 1 on the transmission side, and the communication time can be reduced. Further, traffic on the Internet 4 can be reduced.

As described above, while the retransmission request and the transfer of the image data corresponding to the retransmission request between the gateway device 5 on the receiving side and the facsimile device 7 are performed, the facsimile device 1 on the transmitting side waits until the MCF signal is received. There will be a waiting time. If the state continues as it is, there is no response from the receiving side, and an error ends. In order to prevent this, according to the present invention, when a waiting time occurs, an RNR signal is transmitted from the gateway 3 on the transmitting side to the facsimile apparatus 1 on the transmitting side. This signal is a waiting request, and the facsimile machine 1 can be made to wait by sending this signal. The facsimile machine 1 having received the RNR signal returns an RR signal. If the waiting time is long, the transmission and reception of the RNR signal and the RR signal may be performed periodically.

As described above, when the waiting time occurs, the flow control is performed by the RNR signal and the RR signal, and the facsimile machine 1 on the transmitting side can be made to wait. As a result, it is possible to eliminate a problem such as an error end.

When the receiving-side facsimile apparatus 7 can normally receive the image data by retransmitting the image data from the receiving-side gateway apparatus 5, the receiving-side facsimile apparatus 7 sends out an MCF signal. After the MCF signal is received by the gateway device 5 on the receiving side, it is transmitted to the gateway device 3 on the transmitting side via the Internet 4 and sent to the facsimile device 1 on the transmitting side. The transfer sequence of the image data for one page is completed by the MCF signal, and the transmission side and the reception side can be synchronized. Thereafter, if image data of the second and subsequent pages exists, the transfer of the image data and the transfer of the corresponding MCF signal may be repeated.

When the transfer of all the image data is completed, the facsimile machine 1 on the transmitting side transmits a DCN signal to the gateway 3, and after transmitting the DCN signal to the gateway 5 on the receiving side via the Internet 4, transmits the DCN signal to the gateway 5. Is transferred to the facsimile machine 7. As a result, the facsimile device 1, the gateway device 3, the gateway device 5, and the facsimile device 7 detect the end of the communication, disconnect the line, and end the communication.

As described above, when real-time Internet facsimile communication is performed, only the facsimile apparatus and the gateway apparatus independently communicate on the transmitting side and the receiving side, and the procedure that does not require the use of the Internet 4 is described below. The communication time can be shortened by performing the communication asynchronously. Further, the traffic volume on the Internet 4 can be reduced. For example, if you are communicating in ECM mode,
The image data can be retransmitted between the gateway device on the receiving side and the facsimile device, and the transmission time can be reduced by retransmitting the data without imposing a load on the facsimile device on the transmitting side, the gateway, the Internet, and the like. In this case, the waiting time generated in the facsimile apparatus on the transmission side is controlled by the flow of the RNR signal and the RR signal. Therefore, no trouble occurs due to the occurrence of the waiting time, and the real-time Internet facsimile communication can be performed satisfactorily. it can.

FIG. 2 is an explanatory diagram of an example of a configuration and a communication sequence showing another embodiment of the facsimile system of the present invention. The reference numerals in the figures are the same as those in FIGS.
In the example shown in FIG. 1 described above, the facsimile machine 7 on the receiving side
In the above, an example has been described in which the waiting time generated in the facsimile machine 1 on the transmission side when the retransmission is requested is flow-controlled by the RNR signal and the RR signal. The flow control using the RNR signal and the RR signal is not limited to the above-described case, and can be applied to various cases in which a waiting time occurs in the facsimile machine 1 on the transmission side. FIG. 2 shows an example in which a delay occurs in the transfer of image data on the Internet 4. In such a case as well, a waiting time occurs in the facsimile machine 1 on the transmission side.
Flow control by the R signal is effective.

Hereinafter, the communication sequence shown in FIG. 2 will be described. Note that, as in the case of FIG. 1, the description will be made on the assumption that the image data is transmitted from the facsimile apparatus 1 to the facsimile apparatus 7 in real time by Internet facsimile. Also, communication is performed in the ECM mode.

Termination of modem training from calling by facsimile apparatus 1 (CFR on transmitting side and receiving side)
The sequence up to signal transmission / reception is the same as in the example shown in FIG. 1 described above, and a description thereof will be omitted.

When the training sequence is completed, the image data is transferred. The facsimile device 1 transmits image data to the gateway device 3, and the gateway device 3 transfers the image data to the gateway device 5 via the Internet 4. However, in the Internet 4, the data transfer path is undefined, and the amount of image data is large, so that a delay may occur in some cases. In such a case, first, the facsimile machine 7 on the receiving side
In, there is a wait from the end of training until the image data is actually transmitted. During this waiting time, the receiving-side gateway device 5 is connected to the receiving-side facsimile device 7.
Send a flag to. This prevents the line from being disconnected due to a timeout or the like in the facsimile machine 7 on the receiving side. Then, when the image data arrives at the gateway device 5 on the receiving side, transmission of the image data to the facsimile device 7 on the receiving side is started.

When a delay occurs in the Internet 4 as described above, the facsimile apparatus 7 on the receiving side is operated as described above.
However, since the MCF signal is not transmitted while the image data delayed by the receiving facsimile apparatus 7 is being received, the MCF signal is not transmitted even in the facsimile apparatus 1 on the transmitting side. Waiting for reception of If the state continues as it is, there is no response from the receiving side, and an error ends. To prevent this, an RNR signal is transmitted from the gateway 3 on the transmitting side to the facsimile apparatus 1 on the transmitting side during the waiting time.
Thereby, the facsimile machine 1 can be made to wait. The facsimile machine 1 that has received the RNR signal
Reply signal. If you wait for a long time,
The transmission and reception of the RNR signal and the RR signal may be performed periodically.

As described above, when a waiting time occurs in the facsimile machine 1 on the transmission side due to the delay in the Internet 4, the flow control is performed by the RNR signal and the RR signal, whereby the facsimile apparatus 1 on the transmission side is performed.
And the occurrence of problems such as error termination and retransmission can be eliminated.

When the image data delayed from the gateway device 5 on the receiving side is normally transferred to the facsimile device 7 on the receiving side, the facsimile device 7 on the receiving side sends out an MCF signal. After the MCF signal is received by the gateway device 5 on the receiving side, it is transmitted to the gateway device 3 on the transmitting side via the Internet 4 and sent to the facsimile device 1 on the transmitting side. The facsimile machine 1 on the transmitting side ends the transfer sequence of the image data for one page by receiving the MCF signal.

Thereafter, if image data of the second and subsequent pages exists, the transfer of the image data and the corresponding MCF
The signal transfer may be performed repeatedly. Also for the second and subsequent pages, if a delay occurs on the Internet 4 or the like and the MCF signal does not easily return from the facsimile machine 7 on the receiving side, the flow control may be performed using the RNR signal and the RR signal as described above. The operation after the end of the transfer of the image data is the same as that in the case of FIG. 1 described above, and the description is omitted here.

In the example shown in FIG. 2, the case where a delay occurs on the Internet 4 has been described. However, when a delay occurs due to other causes, the flow control can be similarly performed using the RNR signal and the RR signal.
For example, since the transmitting side and the receiving side independently and asynchronously perform the modem training as described above, the transfer rate on the transmitting side is very high, but the transfer rate on the receiving side is very low. In such a case, the transmitting facsimile apparatus finishes transferring the image data at a high speed, but it takes time for the receiving facsimile apparatus to receive the image data, and the transmission of the MCF is delayed. Even in such a case, a waiting occurs in the facsimile apparatus on the transmitting side. Therefore, by performing the flow control using the RNR signal and the RR signal as described above, it is possible to prevent a problem due to the occurrence of the waiting time.

[0038]

As apparent from the above description, according to the present invention, when real-time Internet facsimile communication is performed, communication is independently performed only between the facsimile apparatus and the gateway apparatus on the transmission side and the reception side. Communication is performed asynchronously for procedures that do not require the use of the Internet. As a result, high-speed facsimile communication can be realized by shortening the communication time, and the amount of traffic on the Internet can be reduced. In particular, when retransmitting image data in the ECM mode, the transmission time can be significantly reduced by performing the transmission between the gateway device and the facsimile device on the receiving side, and the amount of data transferred on the Internet can be significantly reduced. is there.

In addition, since the flow control is performed by the RNR signal and the RR signal in the waiting time in the facsimile machine on the transmitting side caused by using the Internet and the waiting time caused by the execution of the asynchronous procedure as described above, for example, It is possible to avoid problems caused by occurrence of waiting time such as retransmission or communication error due to timeout, and to effectively perform real-time Internet facsimile communication.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an example of a configuration and a communication sequence showing an embodiment of a facsimile system of the present invention.

FIG. 2 is an explanatory diagram of an example of a configuration and a communication sequence showing another embodiment of the facsimile system of the present invention.

FIG. 3 is an explanatory diagram of a configuration example of a conventional real-time Internet facsimile system.

[Explanation of symbols]

1, 7: facsimile machine, 2, 6: public line or extension, 3, 5: gateway device, 4: Internet.

Claims (4)

[Claims] In a facsimile system capable of real-time facsimile communication from a facsimile apparatus to another facsimile apparatus using the Internet via a gateway apparatus, a wait occurs between the gateway apparatus and the facsimile apparatus during ECM communication. When R
A facsimile system wherein flow control is performed using an NR signal and an RR signal. 2. A flow of a waiting time generated between a facsimile machine on the transmitting side and a gateway apparatus on the transmitting side when image data is retransmitted from the gateway apparatus on the receiving side when retransmission is requested by the facsimile apparatus on the receiving side. The facsimile system according to claim 1, wherein the control is performed by using an RNR signal and an RR signal. 3. After the image data transmitted from the facsimile apparatus is transferred through the Internet, a flow control of a waiting time until a response signal is returned from a receiving side is performed by R.
The facsimile system according to claim 1, wherein the facsimile is performed by using an NR signal and an RR signal. 4. A facsimile system capable of real-time facsimile communication from a receiving-side gateway device to a receiving-side facsimile device using the Internet from a transmitting-side facsimile device via a transmitting-side gateway device. A facsimile system comprising a procedure in which communication between a facsimile apparatus and a gateway apparatus on a transmitting side and communication between a facsimile apparatus on a receiving side and a gateway apparatus on a receiving side are executed asynchronously.