JPH0522473A - Isdn terminal equipment - Google Patents

Abstract

(57) [Summary] [Purpose] When an incoming / outgoing call collides, an incoming call from a partner with a high priority is preferentially accepted so that high-priority data transmission can be performed smoothly. [Structure] A plurality of (m) priority incoming call addresses for preferentially accepting incoming calls are stored in the parameter memory 3, and when an incoming and outgoing call collision occurs, the calling number information element of the received call setup message is checked. When the priority of the incoming call is confirmed and the incoming call from the priority called party is detected, the outgoing call operation is terminated and the incoming call operation is performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ISDN terminal device using ISDN as a transmission line.

[0002]

2. Description of the Related Art Generally, in an ISDN terminal device that uses ISDN as a transmission path, when a calling operation is started, another ISDN terminal device simultaneously makes a call and receives a call setup message from a network. It is possible to set whether to ignore the incoming call.

This makes it possible to define the operation performed by the ISDN terminal device when the incoming and outgoing call operations collide.

[0004]

However, such a conventional device has the following disadvantages.

That is, for example, if the calling operation is set to be prioritized when the calling operation collides, the incoming call cannot be answered regardless of the partner terminal which detected the incoming call. In some cases, the inconvenience that the data transmission operation with the important partner cannot be performed quickly may occur.

An object of the present invention is to provide an ISDN terminal device which solves the above-mentioned inconvenience of the conventional device and enables smooth data transmission operation with a partner terminal device having a high priority.

[0007]

SUMMARY OF THE INVENTION According to the present invention, a storage means for storing priority incoming call destination information for prioritizing an incoming call operation and a call setup message when a call setup message is received from the network at the start of the outgoing call operation. When the content of the calling party number information element contained in is matched with the priority incoming call destination information stored in the storage means, the call origination operation started at that time is terminated and the received call setup message is received. It is provided with a control means for shifting to an incoming call operation corresponding to.

[0008]

Therefore, since the partner terminal having a high priority is registered, when a call origination / arrival collision occurs with the partner terminal, the call incoming from the partner terminal is prioritized and It is possible to smoothly perform data transmission with a high partner terminal.

[0009]

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

FIG. 1 shows an ISD according to an embodiment of the present invention.
N facsimile machine is shown. In addition, this ISDN
The facsimile machine uses ISDN as a transmission path and has two machine functions, a group 3 facsimile function and a group 4 facsimile function.

In the figure, the control unit 1 uses this ISDN.
The system memory 2 is for performing operation control processing of the facsimile apparatus, and the system memory 2 stores a processing program executed by the control unit 1 and various data necessary for executing the processing program, and a work area of the control unit 1. It is what constitutes.

The parameter memory 3 is for storing various kinds of information unique to the facsimile machine,
It is composed of a nonvolatile semiconductor memory device such as a battery-backed SRAM (static random access memory) in which data can be rewritten.

The scanner 4 is for reading the original image at the resolution set in the group 4 facsimile apparatus, and the plotter 5 is for recording and outputting the image at the resolution set in the group 4 facsimile apparatus. is there.

The operation display section 6 is for operating the facsimile apparatus, and has various operation keys and
It consists of various display devices such as a liquid crystal display for displaying guidance information to the operator.

The encoding / decoding unit 7 is for encoding and compressing the image signal by a predetermined encoding method and for decoding the image information in the encoded and compressed state into the original image signal. The pixel density conversion unit 8 includes a scanner 4 and a plotter 5.
This is for mutually converting the pixel density of the image and the pixel density of the image that can be transmitted by the terminal device of the other party.

The image storage device 9 is for storing various information such as a transmission image signal, transmission image information, reception image information and reception image signal.

The ISDN interface circuit 10 is an IS
The layer 1 signal control unit 11 is for physically connecting to the DN, and the layer 1 signal control unit 11 controls the signal processing function of the layer 1 of ISDN and the signal of the D channel (signal channel) and the signal of two B channels (information channel). It has an integration / separation function.

The D channel transmission control unit 12 is for performing transmission control processing such as call control processing performed with ISDN using the D channel, and the group 3 facsimile communication control unit 13 uses the B channel of ISDN. Group 3 facsimile communication operation,
The group 4 facsimile communication control unit 14 is for performing a group 4 communication operation by using B of ISDN.

Control unit 1, system memory 2, parameter memory 3, scanner 4, plotter 5, operation display unit 6, encoding / decoding unit 7, pixel density conversion unit 8, image storage device 9, D channel transmission control unit. 12, the group 3 facsimile communication control unit 13 and the group 4 facsimile communication control unit 14 are connected to an internal bus 15, and various information is exchanged between these respective elements mainly via the internal bus 15. Done.

Here, as shown in FIG. 2, the parameter memory 3 stores m priority incoming call addresses.

This priority incoming call address represents the ISDN address of the other party who gives priority to the incoming call when an outgoing and incoming call collision occurs, and is registered by the operator appropriately operating the operation display unit 6. Parameter memory 3
Remembered in.

FIG. 3 shows an example of a call control procedure in the circuit switching mode performed by the terminal device connected to the ISDN with the ISDN.

That is, the calling terminal first sets the circuit switching mode as the transfer mode, and sends a call setting message SETUP with the destination terminal designated as a destination to the ISDN to request call setting with the called terminal. Sends a call setup message SETUP to the designated destination terminal to make a call. The ISDN also sends a call setting acceptance message CALL_PROC for notifying the call setting status to the calling terminal.

Upon detection of an incoming call, the destination terminal sends out a calling message ALERT to the ISDN continuously at a predetermined interval when it is ready to receive an incoming call.
N sends a calling message ALERT to the calling terminal to notify that the calling of the called terminal has started.

When the called terminal responds to the incoming call, it sends a response message CONN to the ISDN, and the ISDN sends a response message CONN to the calling terminal to notify that the called terminal has accepted the call.

The ISDN also sends a response confirmation message CONN_ACK to the destination terminal to confirm the response of the destination terminal, and at that time, an information channel (B channel) for data transmission between the source terminal and the destination terminal. Is established.

As a result, data transmission using the information channel is performed between the calling terminal and the called terminal according to the transmission control procedure set in the transmission function of each terminal.

When the data transmission is completed, the calling terminal sends a disconnection message DISC to ISDN to request the release of the information channel, and ISDN disconnects the disconnection message DISC.
The SC is sent to the destination terminal to notify the restoration of the information channel.

As a result, when the called terminal responds to the ISDN with a release message REL notifying the completion of the channel disconnection, the release message REL is sent from the ISDN to the calling terminal. When the channel release is completed, the calling terminal sends a release complete message REL_COMP to the ISDN to notify it, whereby the ISDN sends a release complete message REL_COMP to the destination terminal to release the information channel. , The information channel established between the calling terminal and the called terminal is completely released.

In this way, the information channel is set between the calling terminal and the called terminal, data transmission is performed, and when the data transmission is completed, the information channel is released.

Further, as shown in FIG. 4A, each message for ISDN call setup has a protocol specification (format, format,
Protocol identifier to identify the sequence, etc.)
Call number to identify which call the message pertains to, message type to identify the content of each message, mandatory information elements that must be added to each message, and each message It consists of additional information elements added as required. Note that 0, 1, or a plurality of essential information elements are set according to the message type, and 0, 1, or a plurality of additional information elements are arranged according to the situation.

The call setup message SETUP is, as shown in FIG. 3B, a "transmission capability" as an essential information element.
And the additional information element is, for example, "calling number",
It has information elements such as "Called number", "Called sub-address", "Lower layer compatibility", "Higher layer compatibility", and "User-user".

Also, a release completion message REL_COM
P has, for example, "reason display" as an essential information element, and has information elements such as "display" and "user / user" as additional information elements.

An outline of these information elements will be described.

The "Transmission capability" information element is an information transfer indicating whether the content of information to be transmitted is voice, unrestricted digital information, restricted digital information, 3.1 KHz audio, 7 KHz audio, or video. Capability, transfer mode indicating whether the switching function used is circuit switching or packet switching, information transfer speed indicating information transfer speed, information indicating information transfer mode, and information indicating user information protocol, etc. Consists of.

The "calling number" information element is the ISDN of the calling terminal.
The "source subaddress" information element, which represents a number, is used to identify a target terminal among a plurality of terminals connected to the same home wiring (passive bus) on the calling side. The "Called Number" information element represents the ISDN number of the called terminal.
The "destination sub-address" information element is for identifying the intended one of the plurality of terminals connected to the same home wiring on the destination side.

The "lower layer compatibility" information element is used for the communication possibility check with the partner terminal, and its basic content is the same as the "transmission capability" information element. Furthermore, this "lower layer compatibility" information element contains more detailed content.

The "higher layer consistency" information element is used for consistency check with the partner terminal, and is, for example, group 2 / group 3 facsimile, group 4
The terminal function of the facsimile, mixed mode, teletex, videotex, telex, or message handling system is displayed.

The "user-user" information element is intended to be used for the communication of information between users, the content of this "user-user" information element being transferred transparently without being interpreted by the ISDN. It is transmitted to the other user.

The "reason indication" information element is a message containing the information element (in this case, the release completion message REL_).
It is for notifying diagnostic information indicating the reason why COMP) is generated or the reason for an error that has occurred during the call setup procedure.

FIG. 5 shows an example of processing performed by the ISDN facsimile apparatus at the time of making a call.

For example, when an operator sets a transmission original on the scanner 4 and inputs a transmission destination, and then commands the start of image information transmission, a calling operation is started and a designated destination is called first. Call setup message SET for
The UP is formed and sent to the ISDN (process 101).

Then, the process waits until any call setting message is received from the ISDN (process 102). When the call setting message is received, the call setting message SE is received.
It is checked whether it is TUP (decision 103).

When the result of the judgment 103 is YES, it is checked whether or not the content of the "calling number" information element included in the received call setting message SETUP is stored in the parameter memory 3 as the priority incoming call address. (Process 104, decision 105).

When the result of the determination 105 is YES, the calling operation is terminated at that point, and the release completion message REL_COMP is sent to terminate the calling operation (process 106), and then the received call setting message SE is received.
The incoming call procedure for TUP is started (process 107), and the subsequent processes are performed.

On the other hand, the received call setting message SETU
When the content of the "calling number" information element included in P is not stored in the parameter memory 3 as the priority incoming call address, and the result of the determination 104 is NO, the incoming call is ignored (process 108), the process 102 is returned to, and I
The call setting message sent from the SDN is received.

When the result of the determination 103 is NO, the process proceeds to the normal calling procedure.

With the above configuration, as shown in FIG.
N facsimile machine TA is ISDN facsimile machine T
IS to call setup message SETUP to originate B
When sent to the DN, the ISDN sends a call setup acceptance message CALL_PROC.

At this time, when another ISDN facsimile apparatus TC sends out a call setting message SETUP for calling the ISDN facsimile apparatus TA almost at the same time, the call setting message SETUP from this ISDN facsimile apparatus TC is, for example, Immediately after receiving the call setting acceptance message CALL_PROC, it is received by the ISDN facsimile apparatus TA.

At this time, the ISDN facsimile machine TC
However, when the ISDN facsimile apparatus TA is not set as a priority call destination, the ISDN facsimile apparatus TA ignores the call setting message SETUP and performs a call setting procedure operation with the ISDN facsimile apparatus TB.

When the information channel is established, the data transmission operation is performed between the ISDN facsimile apparatus TA and the ISDN facsimile apparatus TB using the established information channel.

On the other hand, as shown in FIG. 7, at the same time as the ISDN facsimile apparatus TA sends a call setup message SETUP to the ISDN to call the ISDN facsimile apparatus TB, another ISDN facsimile apparatus TD sends an ISDN facsimile apparatus. Consider a case where a call setup message SETUP for calling the device TA is sent to the ISDN, and the ISDN facsimile device TD is registered as a priority incoming call destination in the ISDN facsimile device TA.

In this case, the ISDN facsimile machine TA
Sends a data release completion message REL_COMP indicating the communication refusal to the content of the "reason indication" information element to the ISDN facsimile machine TB, terminates the call setup procedure operation, and
A response message CONN is sent to D, a call setup procedure operation is performed, and an information channel is established.

After that, the data transmission operation is performed between the ISDN facsimile apparatus TA and the ISDN facsimile apparatus TD using the established information channel.

In this way, in this embodiment, when the priority incoming call destination is registered in advance, and when the incoming and outgoing call collision occurs, the partner terminal which has detected the incoming call is registered as the priority incoming call destination, Since the call setup procedure operation started by the own terminal is aborted and the call setup procedure operation that detects an incoming call is performed, high-priority data transmission can be appropriately performed.

In the above-mentioned embodiment, when the called terminal of the called side at the time of the calling and called call collision is not registered as the priority called destination, the called call is ignored. In order to give a clear notice of refusing
A release completion message REL_COMP may be sent in which data indicating communication refusal is set in the content of the "reason indication" information element.

By the way, in the above-mentioned embodiment, the case where the present invention is applied to the ISDN facsimile apparatus has been described, but the present invention can be similarly applied to other ISDN terminal apparatuses.

[0058]

As described above, according to the present invention,
Since a high-priority partner terminal is registered, if an incoming / outgoing call collision occurs with such a partner terminal, the incoming call from that partner terminal is prioritized and An effect is obtained that data transmission between them can be smoothly performed.

[Brief description of drawings]

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

FIG. 2 is a schematic diagram showing a storage mode of a priority incoming call address.

FIG. 3 is a time chart showing an example of a call setup procedure performed with ISDN.

FIG. 4 is a schematic diagram for explaining a signal type of a call setting signal.

5 is a flowchart showing an example of processing performed by the device of FIG. 1 when making a call.

FIG. 6 is a time chart for explaining an operation when it is detected that a call is made from a terminal not registered as a priority call destination, immediately after the call operation is started.

FIG. 7 is a time chart for explaining an operation when it is detected that a terminal registered as a priority call destination is called immediately after the call operation is started.

[Explanation of symbols]

 1 system control unit 2 system memory 3 parameter memory

Claims (1)

Claims: 1. ISDN using ISDN as a transmission line.
In the terminal device, storage means for storing priority incoming call destination information for prioritizing the incoming call operation, and a calling number information element included in the call setup message when the call setup message is received from the network at the start of the outgoing call operation. The content of the priority call destination information stored in the storage means, the call operation started at that time is terminated and the call operation corresponding to the received call setting message is entered. An ISDN terminal device, comprising: