JPH0619371U - Facsimile communication system - Google Patents

Abstract

(57) [Summary] [Purpose] It is an object of the present invention to provide a facsimile communication system capable of more reliably responding to a user's request that the manuscript set must be transmitted. [Composition] When all the transmission attempts in the circuit switching mode by automatic redial are rejected, the calling side transmits the facsimile image data in the packet switching mode, while the called side sets up in the packet switching mode. In response to this, the image data is received.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a facsimile communication system using an ISDN line.

[0002]

[Prior art]

 In the ISDN basic interface structure (2B + D), as shown in FIG. 9, when a facsimile machine (hereinafter, abbreviated as FAX) 1 tries to send to a destination FAX 2, FAX 4 and other FAX 3 are transmitted at the destination. When communication is being performed using the B2ch between the two, and when a communication is being performed between the telephone (hereinafter abbreviated as TEL) 2 and another TEL1 using the B1ch, the busy state is assumed. Communication is rejected. In such a case, the FAX1 which is about to be sent will automatically re-dial a few minutes later and resend it to meet the user's request that the manuscript once set should be sent as much as possible. I'm supposed to try.

[0003]

[Problems to be solved by the device]

 However, if all the transmission attempts by the automatic redialing are rejected, an error occurs and the transmission is given up, and the above user request cannot be sufficiently satisfied. In view of the above circumstances, the present invention has an object to provide a facsimile communication system capable of more reliably responding to a user's request that the set original should be transmitted as much as possible.

[0004]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the facsimile communication system according to the present invention allows the calling side to use the facsimile image in the packet switching mode when all transmission attempts in the circuit switching mode by automatic redial are rejected. On the other hand, the called side is provided with a means for controlling to receive the image data in response to the setup in the packet switching mode.

[0005]

[Action]

 In the above configuration, for example, when the calling side receives several communication refusals in the setup for setting SAPI0 (circuit switching mode), the setup is switched to setting for SAPI16 (packet switching mode). On the other hand, the destination terminal responds to this packet switching mode request by designating the D channel as the used channel. As a result, even if both B1 and B2 are used in the circuit switching mode, the facsimile image data transfer is performed by packet switching on the D channel. That is, even if the other party is busy, the set original is always transmitted.

When the B2 channel is used in the circuit switching mode and the B1 channel is used in the packet switching mode, facsimile image data transfer may be performed by packet switching on the B1 channel. In this case, the network side should handle the B1 channel so that the receiving terminal can exchange packets with two or more parties.

[0007]

【Example】

 [Embodiment 1] An embodiment of the present invention will be described below with reference to FIGS. 1 to 6. FIG. 1 is a diagram showing a schematic configuration of a facsimile machine 100 that uses ISDN. This facsimile machine 100 controls the protocol processing unit 1 connected to the ISDN and the entire facsimile machine, and under a predetermined condition. Central control circuit 2 for performing processing for shifting to transmission in the packet switching mode (during transmission), processing for designating the D channel when busy in the packet switching mode transmission request (during reception), etc. 2, a memory 3 connected to the central control circuit 2, a key identification circuit 4 connected to the central control circuit 2, various keys 5 connected to the key identification circuit 4, and a display control circuit 6 connected to the central control circuit 2. A display 7 connected to the display control circuit 6, a reading section 8 for reading the contents of the original by a CCD line sensor, and the read image data is encoded. A coding unit 9 for decoding the received coded image data, a recording unit 11 for recording on the recording paper based on the decoded image data, and a command from the central control circuit 2. A selection switch circuit 12 for switching between connecting the encoding unit 9 to the protocol processing unit 1 or connecting the encoding unit 9 to the protocol processing unit 1.

FIG. 2 is a flowchart showing a process of shifting to transmission in the packet switching mode under a predetermined condition. First, as an initial setting, a process of I (number of transmission tries) ← 0 is performed (S1). Then, a transmission try is made in a setup with SAPI0 (circuit switching mode) (S2), and it is determined whether this transmission try is permitted (S3). If permitted, the transmission in the circuit switching mode is executed (S4), while if not permitted, the process of I ← I + 1 is executed (S5), and it is determined whether I> x (S6). It should be noted that x is initially registered when the facsimile is installed and indicates the number of times the transmission is to be tried. If I> x is not found in the above judgment processing, the process proceeds to step 2 to repeat the transmission try. On the other hand, if I> x, the SAPI16 (packet exchange mode) is switched to the setup and the transmission try is carried out (S7). If the communication permission is obtained in this transmission try, the transmission is executed by packet exchange (S9). On the other hand, if the communication permission is not obtained in this transmission try, an error message is displayed and the process ends.

FIG. 3 is an explanatory diagram of a LAP-D frame structure. This LAP-D frame includes a start flag part, an address part, an information part, an FCS (frame check sequence) part, and an end flag. And part. When step 7 is executed, the SAPI in the address part is set to 16. FIG. 4 shows a calling procedure when a call is made using the D channel. Frames such as SABME and UA are exchanged between the 25 terminal (facsimile device), the TA (terminal adapter) and the network, and then the X.X.X. 25 Calling (CR) packets are forwarded.

FIG. 5 shows the X. FIG. 25 is a diagram showing an incoming call procedure performed between the 25 terminals (facsimile device), the TA (terminal adapter), and the network, and the TA specifies to use the D channel for setup from the network. . Then, the link setting of S API 16 is performed, and the PH.X. 25. The incoming call (IC) packet was transferred, and thereafter, X.25. Communication is performed in the procedure of 25. FIG. 6 is a diagram showing the relationship between the caller side terminal, the ISDN and the callee side terminal. The ISDN indicates the callee side of the packet switched call by the setup message regardless of the caller side channel. Notify the terminal. Then, the called terminal will specify the D channel by CONN. Both the calling side and the called side have joined the D channel packet service. Second Embodiment Another embodiment of the present invention will be described with reference to FIGS. 7 and 8. In the above-described embodiment, the countermeasure is taken when both the B1 and B2 channels are used in the circuit switching mode, whereas in the present embodiment, as shown in FIG. 7, the B2 channel is in the circuit switching mode. , And the measures for the case where the B1 channel is used in the packet switching mode. In such a case, as shown in FIG. 8, the image data transfer can be performed by using the packet switching mode on the B1 channel. In this case, on the network side, the receiving terminal side can exchange packets with the B1 channel to two or more parties.

Also in the above configuration, the set original is always transmitted, and it is possible to more reliably meet the user's request that the set original should be transmitted as much as possible. It should be noted that whether or not the calling side transmits the image data in the packet switching mode may be selectable by the user.

[0012]

[Effects of the Invention] As described above, according to the present invention, even when the other party is busy and the communication is originally refused, the packet switching mode is used to perform the transmission. This has the effect of more reliably meeting the request of the user who wants to send it.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a facsimile apparatus that constitutes a facsimile communication system as an embodiment of the present invention.

FIG. 2 is a flowchart showing a process of shifting to transmission in a packet switching mode under a predetermined condition.

FIG. 3 is an explanatory diagram of a LAP-D frame structure.

FIG. 4 is an explanatory diagram showing a control procedure when making a call using a D channel.

FIG. 5: X. It is explanatory drawing which shows the incoming call procedure performed between 25 terminals, TA, and a network.

FIG. 6 is a diagram showing a relationship among a calling side terminal, an ISDN (HD), and a called side terminal.

FIG. 7: B2 channel used in circuit switched mode,
It is a figure which shows notionally that a transmission try by circuit switching mode is refused when B1 channel is used by packet switching mode.

FIG. 8 is a diagram conceptually showing a case where image data transfer is performed using a packet switching mode on a B1 channel.

FIG. 9 is a diagram conceptually showing that a transmission try in a circuit switching mode is rejected when both B1 and B2 channels are used in the circuit switching mode.

[Explanation of symbols]

 1 Protocol Processing Unit 1 2 Central Control Circuit 100 Facsimile Machine

Claims (1)

[Scope of utility model registration request] 1. A caller, in a packet-switching mode, transmits facsimile image data, while a caller, in a packet-switching mode, transmits the facsimile image data when all the transmission attempts in the circuit-switching mode by automatic redial are rejected. A facsimile communication system comprising means for controlling to receive the image data in response to the setup.