JPH1013531A - Gateway exchange used for loopback call connection communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain a speech only to an incoming call of a caller replying with a call from a called party by allowing a gateway exchange to transfer connection data to a called exchange extracted from the connection data sent through the use of a user to user information (UUI) service from the router through the use of packet communication. SOLUTION: A router 12 is connected to a Japan side gateway exchange connecting to a called gateway exchange 5 via a D channel of a channel 2. Then the gateway exchange 3 is provided with a function of extracting the called exchange 5 from connection data sent from the router 12 by using the UUI service and a function of transferring the connection data received by the called exchange 5 through the use of packet communication. In this case, the router 12 receiving a call from the called exchange 5 uses a management number obtained by analyzing the UUI data received from the called exchange 5 to discriminate the call to be the incoming call in the standby state made before by the router 12, the router 12 sends a permission reply to the called exchange 5 in terms of UUI data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a return call connection communication system in which connection data is transmitted from an extension communication terminal device accommodated in a PBX to a receiver and communication is performed by a return call connection from the receiver. And a gateway exchange used for this return communication system.

[0002]

2. Description of the Related Art In recent years, low-cost international telecommunications services utilizing the difference between callers between carriers and the difference between inside and outside countries have been used. There are roughly two types of services. One is the "call back (return phone) method"
And the other is called "direct-through system". In the latter case, you can call the gateway exchange installed on the Japanese side, dial your password and the destination number, and provide the discounted international communication service set on the gateway exchange side. Calls can be made with foreign countries via an international communication network that is mediated by a carrier. This direct communication method is inconvenient because the gateway exchange must be called every time an international call is made. In order to solve this inconvenience, there is a commercially available dedicated adapter for automatically calling a gateway exchange when making an international call. This adapter stores the gateway exchange number and the password in advance. Therefore, if this adapter is attached to the line, the user can receive the provision of the international telecommunications service at a low price only by dialing the destination number information.

[0003] FIG. 12 shows a system for using a bargain international communication service of the direct type provided with the above adapter. As shown in this figure, a dedicated adapter 19 is attached between an automatic private branch exchange (PBX or key telephone) 11 of the user 1 and the domestic public network 2.
That is, the extension communication terminal devices 15 such as the plurality of telephone terminal devices 15-1 and 15-2 and the facsimile communication device 15-3 accommodated in the extension of the PBX 11 are connected to the domestic public line 2.
A dedicated adapter 19 is attached to each of the trunks 17 to be connected to each other. This dedicated adapter 19
Has the following features: (1) A function of identifying a dial number and, if it is a dial for international communication (for example, “001”), storing a subsequent country code and a destination number. For domestic numbers,
A function to make domestic numbers through. (2) A function of automatically transmitting the number of the international gateway exchange (Japanese exchange center) 3 registered in advance. (3) A function of automatically transmitting a personal identification number and a destination number in response to a response from the gateway exchange 3. (4) A function of connecting a line connected from the other party (the receiving side) to the extension communication terminal device 15 on the calling side.

[0004] However, such a conventional system for using the bargain international telecommunication service by the direct communication method using a dedicated adapter has the following problems. (A) Since it is necessary to install dedicated adapters as many as the number of trunks of the PBX, if the number of trunks is large, the installation work is also difficult, and the cost is particularly high. (B) The domestic call charge from the communication terminal device 15 on the calling side to the Japanese switching center (international gateway exchange) 3 via the domestic public network 2 is borne by the calling side. For this reason, the cost burden is large for a long-distance subscriber.

[0005] One of the inventors of the present invention, Hideki Shikiba, described an international telecommunications service utilization system that can solve the above-mentioned problems and a router for international telecommunications services used therefor. It has already been invented as a "communication service utilization system" (Japanese Patent Application No. 7-285701).

[0006] The invention according to the above-mentioned application calls a Japanese exchange center (gateway exchange) from a domestic communication terminal, selects an international telecommunications service company (incoming exchange center) desired by the exchange center, and selects it. A system for using international telecommunications services for performing international telecommunications with overseas communication terminal devices via an international telecommunications network mediated by the international telecommunications service company. An international telecommunications service router callable from one communication terminal device is connected between the automatic private branch exchange and the ISDN line of the domestic public switched telephone network, and communicates with the overseas through the following procedure. I have.

A system for using an international telecommunications service according to the invention according to the above application will be described with reference to FIG. The international telecommunications service utilization system according to the above application is:
A user 1 having an automatic private branch exchange (PBX) 11 installed therein, a domestic public network 2, an international communication network 4,
And a Japanese exchange center (international gateway exchange) 3. The user 1 has a PBX 11 that accommodates an office trunk 17 connected to a domestic public network 2 (for example, NTT (registered trademark) network). This PB
On the extension side of X11, a number of extension telephone terminal devices 15-
1, 15-2 and a facsimile communication device 15-3, etc., are connected, and in addition, a router 12 'corresponding to a conventional dedicated adapter as an automatic handling device for one international telecommunication service. Is housed. Further, the router 12 'is connected to the ISDN of the domestic circuit network 2.
It is connected to a line (for example, INS64 of NTT). The domestic public network 2 is connected to an international communication network 4. A gateway exchange (Japan-side exchange center) 3 is connected between the domestic public network 2 and the international communication network 4. Similarly, a gateway exchange (reception-side switching center) not shown is connected between the international communication network 4 and a domestic public telephone network of a partner country not shown.

[0008] The router 12 'has the following functions, similarly to the existing dedicated adapter on the market. (1) A function of storing the dialed country code and destination number. (2) A function of automatically transmitting the number of the pre-registered Japanese exchange center (gateway exchange) 3. (3) A function of automatically transmitting a personal identification number and a destination number registered in advance corresponding to the gateway exchange 3 using a UUI service. (4) A function of connecting a line connected from the other party (the receiving side) to the extension communication terminal device 15 on the calling side. The router 12 'is assigned a predetermined extension number or a special number (special number) in addition to these functions, and can be accessed from a plurality of extension telephone terminal devices. In this example, the router 12 ′ is connected to the extension side. Alternatively, the router 12 ′ may be connected to the trunk 17. Further, the PBX 11 may be configured so that the router 12 'can be selectively connected to both the extension side and the trunk side.

Next, referring to FIG. 14, a description will be given of a connection procedure of a communication line when a telephone call is made overseas using the above-mentioned international telecommunication service utilization system. First, when using the international communication service, the calling user dials the number determined by the extension communication terminal device 15 and calls the router 12 '(). This number is stored in router 1 in advance.
2 ′. When the router 12 'is thus accessed from one of the extension communication terminal devices 15, the router 12' generates a response signal tone and notifies the originating extension communication terminal device 15 of the access (). After confirming the response tone, the user dials the destination number information (). The called party number information is the country code of the called party and the called party's phone number. Thereafter, the user on the calling side waits with the receiver of the extension communication terminal device 15 raised.

[0010] On the other hand, upon receiving the destination number information, the router 12 'activates the INS line, sets the D channel, and uses the user-to-user information notification service (UUI) to switch to the Japan-side switching center (UUI). An ID number, a password and a destination number information are sent to the international gateway exchange 3 as information between users, and a call is set ().

The Japanese exchange center 3 checks the ID number and the password of the supplied information and confirms that they are appropriate. Back number) to a switching center on the partner country side via a common signal path using a packet network. For example, if the partner country center is in the United States,
The request is sent to the US-side switching center 5 to request the subsequent connection ().

The US-side switching center 5 calls the called communication terminal 6 based on the received country code and called telephone number, connects the line, and connects the communication line with the called telephone terminal 6. Yes ().

Next, when there is a response () from the receiving-side communication terminal device 6, the US-side switching center 5 does not pass through the Japanese-side switching center 3 via the communication path using the large discount line but without passing through the Japan-side switching center 3. The call is connected to the network 2 (), and a call is connected to the extension communication terminal device 15 of the calling side user through the B channel of the INS line of the domestic network 2 (). As a result, the extension communication terminal device 15 and the receiving-side communication terminal device 6 are connected by the bargain international telecommunication service, and an international call is possible.

Here, the generation of the call charge, that is, the start of the charging, is performed when the connection with the calling side is completed via the B channel of the INS line as described above. The monitoring and recording of the billing are performed by the Japanese exchange center 3 and the United States exchange center 5.

FIG. 15 is a schematic block diagram of the router 12 '. The router 12 'includes a transmission side monitoring circuit 12', a signal tone transmission circuit 12'-2, a number reception circuit 12'-3, a telephone current supply circuit 12'-4,
Communication path control circuit 12'-5, memory 12'-6, information transmission circuit 12'-7, and D channel control circuit 12'-
8, a receiving side monitoring circuit 12 ′-9, and a terminal adapter (TA) 12 ′-10, to the extension communication terminal device 15 via the PBX 11 and to the domestic public line via the digital service unit (DSU) 14. Connected to network 2. The transmission side monitoring circuit 12'-1 detects that each communication terminal device 15 has accessed the exchange.
The signal sound transmission circuit 12'-2 generates a response signal sound and transmits it to the communication terminal device 15. Number receiving circuit 12'-3
Receives the destination number supplied from the communication terminal device 15 and temporarily stores it in the memory 12'-6. The communication path control circuit 12'-5 controls the D channel control circuit 12'-8 to activate the D channel, and the information transmission circuit 1 '
The terminal adapter 12 'is controlled by driving the 2'-7.
The ID number and the password registered and stored in the memory 12'-6 are sent to the Japanese exchange center 3 via -10. When there is an incoming call response, the call control circuit 12'-5 connects the communication terminal device 15 on the transmitting side to the receiving side. In addition, the receiving side monitoring circuit 12'-9 receives an incoming response from the receiving side terminal device.

In such a system, first, a specific number for calling the international telecommunications service router 12 'is dialed from one of the domestic communication terminals 15 on the calling side to call the router. Next, a response signal is transmitted from the called router 12 ′ to the communication terminal device 15. When receiving the destination number information including the destination country code and the destination number transmitted from the communication terminal device 15 that has received the response signal, the router 12 ′ activates the D channel of the ISDN line 2. Then, an ID number, a password, and the other party number information are transmitted as inter-user information to the Japanese exchange center 3 using an inter-user information notification (UUI) service. The Japanese exchange center 3 discriminates the received ID number and personal identification number, and when these numbers are determined to be legitimate, sends the destination number information to the destination country exchange center 5. The request is transmitted to request a line connection to the communication terminal device 6 on the called side to which the called party number is assigned. On the other hand, when the gateway exchange of the destination switching center 5 receives a response signal indicating that the line has been extended from the receiving side and has been connected to the communication terminal device 6 on the receiving side, the BCH of the ISDN line Is started, and the communication terminal device 15 on the transmitting side is connected to the communication terminal device 6 on the receiving side via the channel and the router 12.

In this system, the international telecommunications service router corresponding to the prior art dedicated adapter is:
As an automatic device that handles international communication services, it has a predetermined extension telephone number or a special number, and can be called from a plurality of extension telephones. Of course, two routers
More than two units may be installed, and the number may be set according to the call volume of the user. Extension 1 based on general usage
One or two routers may be installed for every 00 routers. As described above, according to the method of the present invention, since one router handles a plurality of extension communication terminals, the cost is reduced as compared with the conventional case where a dedicated adapter is installed for each trunk, and The installation work of the dedicated adapter is simplified, and the construction cost can be reduced.

In the invention according to the aforementioned application, an ISDN line (NTT's ISN network 6) is used as a domestic communication line network.
4) is used. In particular, in this method, an ID number, a password, a destination country code, and a called party number are transmitted as inter-user information using an inter-user information notification service (UUI). This service is provided by NTT
It is provided as an I service, and is a function that allows a user to transmit and receive a certain amount of information to and from another user through a signal (D) channel. The communication fee of the current UUI service is 0.4 per message (128 octets).
It is a yen and the monthly fee is free.

Thus, in the invention according to the above-mentioned application,
Since the communication of information for the outgoing connection uses the inter-user information notification service via the ISDN line, the communication cost for the outgoing connection is extremely low. In addition, the communication charges for actual calls are low because they are international incoming calls. Therefore, according to the method of the present invention, domestic call charges are low, call charges from a long distance are also low, and it is easy to use from a long distance.

[0020]

In the above-mentioned under-priced international communication service, the originating extension communication terminal device originates an international call through a router, and then waits for a return call connection to the originating extension communication terminal. Therefore, when there is another incoming call, a call is established for the other incoming call, and there is a problem that a correct international call cannot be made. Furthermore, in the above-mentioned undervalued international communication service, if the originating extension communication terminal device originates an international call via a router, then abandons the call while waiting and transmits a new call, a call back connection to the previous call is made. In such a case, there is a problem in that the return call connection is supported, and an international call with a new party cannot be made.

According to the present invention, there is provided a communication system in which a call is established by making a return call connection from a called side when a call is transmitted from a calling side extension communication terminal apparatus. Gateway exchange for use in a system in which a call can be originated through the network and a call made to the router in the middle of waiting for a return call connection can be answered only to an incoming call for the waiting communication. The purpose is to provide.

[0022]

In order to achieve the above object, the present invention provides a plurality of extension communication terminals accommodated in a PBX, and at least one router accommodated in the PBX and connected to a public line network. An originating gateway exchange connected to the router via a public line network, a communication network, a destination gateway exchange connected to the originating gateway exchange via a communication network, and a terminating gateway exchange connected to the originating gateway exchange. Return call connection communication using a communication system including a connected destination communication terminal device, and waiting for a return call connection from the destination gateway exchange for communication originating from the originating extension communication terminal device to perform a call. In the gateway exchange used for the system,
A function of extracting the destination gateway exchange from the connection data transmitted from the router to the originating gateway exchange using the user information notification (UUI) service, and a function of extracting the connection data received from the router to the destination gateway exchange. Added function to transfer using packet communication.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a conceptual diagram showing an outline of a configuration of an international communication system to which an international communication service using a router according to the present invention is applied. This international communication system is connected to a user 1 having an automatic private branch exchange system (PBX) 11 for transmitting international communication from within Japan, an ISDN public line network 2, and connected to the user 1 via a public line network 2. Japanese exchange center (gateway exchange) 3
An international communication network 4 connected to the public line network 2, a receiving side exchange center (gateway exchange) 5 connected to the Japanese switching center 3 via the international communication network 4, 4 comprises a receiving terminal device 6 accommodated in a receiving public telephone network. Public line network 2
For the international communication network 4, an ISDN line 7 having a B channel and a D channel is used.

The user 1 further includes an automatic private branch exchange (PBX) 11, a router 12 housed on the extension side of the PBX, and a digital service unit (DSU) connected to the router 12 and interfacing with the public network 2. ) 14
And a plurality of extension telephones 15-1 and 15-1 accommodated in the PBX
An extension communication terminal device 15 such as a 5-2 or facsimile terminal device 15-3 and at least one central office trunk 17 for interfacing the PBX 11 with the public network 2.

FIG. 2 shows an outline of the structure of the router 12.
The router 12 is a changeover switch 1 connected to the PBX extension.
21; incoming call detection means 122; 2/4 conversion means 123; codec (CODEC) circuit 124;
An international communication transmission / reception system comprising: a busy tone (BT) detection means 126 and a push button (PB) signal receiver 127; a layer 1.2.3 control section 128;
Receiver 129 and PBX interface control unit 130
Main control unit 131, storage means (RAM) 132,
And display means (LEDs) 133 and 134.
There are two international communication transmission / reception systems.

The incoming call detecting means 122 is a means for detecting a call signal from the PBX. When detecting an incoming call from the extension telephone, the incoming call detecting means 122 constantly switches the changeover switch 121 connected to the incoming call detecting means 122 to the international communication originating / receiving system. Switch to
The 2/4 conversion means 123 is a hybrid circuit for 2-wire-4 wire conversion. The codec circuit 124 converts an analog signal from the PBX 11 into a digital signal, converts a digital signal from the line into an analog signal, and generates various tones (DT, BT). Loop circuit 125
Closes a DC loop for the extension terminal of the PBX 11 and the 2/4 conversion means. Busy tone detecting means 126
Detects a busy tone from the PBX 11 and the codec circuit 124, and releases the DC loop circuit 125. The PB signal receiver 127 receives a push button (PB) signal from the PBX 11 and develops it into a dial number.

The layer 1, 2, and 3 control unit 128 and the driver / receiver 129 select ports to be connected to the B1 and B2 channels and the D channel of the INS net 64 and form a user network interface with the INS net 64. PBX interface control unit 1
30 is an incoming call detecting means 122, a loop circuit 125,
It controls the busy tone detecting means 126 and the display device 133. The main control unit 131 includes a codec circuit 124, a layer 1, 2, 3 control unit 128, and a driver / receiver 1
29, the PBX interface control unit 130, the main control unit 131, the storage unit 132, and the display unit 134. The storage means (RAM) 132 stores a Japanese switching center number, a membership number (ID), a personal identification number, a return call connection number (callback number), a dial end identification, and the like, which are downloaded as UUI data from the Japanese switching center 3. Is stored in the battery. Display means (LED) 133
Indicates that the analog ports (ext. 1 and ext. 2) are in use,
Displays the status such as waiting. A display unit (LED) 134 connected to the main control unit 131 displays a state such as busy or incoming call on the line.

The functional configuration of the router 12 will be described with reference to FIG. The router 12 is provided with a management number assigning function 135 for assigning a management number every time a call is transmitted from the extension communication terminal device 15 via the PBX 11, and from the data sent at the time of the return call connection from the receiving side exchange center (gateway exchange) 5. A management number extraction function 136 for extracting a management number, a match detection function 137 for comparing a management number assigned by the management number assignment function 135 with the extraction management number extracted by the management number extraction function 136 and detecting a match, It has an incoming call connection function 138 for connecting a call arriving at the router when the number matches the extraction management number to the extension that originated the international call.

The outline of the standard pattern of the system operation of the international communication service according to the present invention will be described with reference to FIG.
In using the present system, first, the Japan-side exchange center number, member number (ID), personal identification number, return call connection number to be used for the call origination / reception operation from the Japan-side exchange center 3 to the router 12 accommodated in the PBX 11 in advance. (Callback number) and data such as dial end identification are downloaded. When the extension telephone 15 goes off-hook, the PBX 11 sends a dial tone to the extension telephone 15.

When the extension number of the router 12 is dialed from the extension telephone 15 receiving the dial tone, the PBX 11
Sends a call signal (hereinafter referred to as an IR signal) to the router 12 to call the router 12. The router 12 that has detected the arrival of the IR closes the loop circuit 125 and makes a second dial tone (second dial tone:
Hereinafter, referred to as an SDT signal). The extension telephone 15 receiving the SDT signal dials the destination telephone number including the international telephone number as a push button signal (hereinafter, referred to as a PB signal).

The router 12 having received the destination telephone number selects the Japanese switching center 3 from the international telephone numbers included therein, sets up a D-channel call to the Japanese national switching center 3, and sets the member number and the like. UUI data including connection data such as a personal identification number, an international telephone number and a callback number, and data such as a management number updated and assigned each time international communication occurs is transmitted.

Japanese exchange center 3 receiving the UUI data
Analyzes the received data received from the router 12, sees whether the membership numbers and passwords match, and, based on the result, sends a permission response (hereinafter, referred to as ACK) or a rejection response (hereinafter, referred to as NAK) to the router 12. Send to When the result of the data analysis is normal, after transmitting the "ACK" data to the router 12, the D-channel connection with the router 12 is released, and a call is set to the destination switching center 5 via the international communication network. For example, connection data and UUI data such as a management number are transmitted by packet communication or the like.

When an "ACK" is received from the Japanese switching center 3, the router 12 transmits a waiting sound (second ring back tone, hereinafter, referred to as SRBT) to the calling-side extension communication terminal device 15 while transmitting the "ACK" from the Japanese switching center 3. The line with the local exchange center 3 is opened. From the Japanese exchange center 3, "N
If "AK" is present, the line side with the Japanese switching center 3 is released, and a busy tone (hereinafter referred to as BT) is transmitted to the originating extension communication terminal device 15.

The extension telephone 15 receiving the waiting sound "SRBT" waits for a return call connection from the called-side switching center 5 while off-hook.

On the other hand, the receiving side switching center 5 receiving the call from the Japanese side switching center 3 extracts the callback number and the like from the received UUI data, and
A call is set to the router 12 via the line 7 without passing through the Japanese switching center 3, and the received UUI data including the management number is transmitted. At the same time, the receiving-side switching center 5 extracts the telephone number of the receiving-side from the received UUI data, calls the receiving-side telephone 6, and executes the call setting process.

The router 12 that has received the call from the receiving-side switching center 5 uses the management number obtained by analyzing the UUI data received from the receiving-side switching center 5 to send a call to the router 12 and wait for a call. It is determined whether or not the call is an incoming call. If the incoming call is a standby call, “ACK” is transmitted to the receiving-side switching center 5 using UUI data. Router 1
2 transmits “NAK” as UUI data to the receiving-side switching center 5 when the incoming call is not a call waiting.
On the other hand, when there is another incoming call to the router during the standby, the presence or absence of UUI data is monitored. If there is no UUI data, the call is determined to be a general call and the incoming call is rejected, and only when there is UUI data. Perform the above process.

The extension telephone 15 listens to the ringing tone (ring back tone, hereinafter referred to as RBT) of the called user 6 sent via the called-side switching center 5 and, when a response is received from the called user 6. Initiate a call.

To end the call, when the extension telephone 15 is on-hook, the PBX 11 detects the on-hook and sends “BT” to the router 12. The router 12 that has detected "BT" activates the timer, releases the loop approximately three seconds later, and disconnects the connection with the public network (ISDN network) 2. The public line 2 that has received this disconnection process executes a disconnection process with the international communication network 4. When detecting the disconnection process, the international communication network 4 executes a process of opening the public network 2, and the public network 2 executes a process of opening the router 12. When the release is completed, the release completion data is transmitted from the router 12 to the public line network 2 and the international communication network 4, and the release processing ends.

Next, the service function will be described.
A router having an integrated digital communication network connection function of analog communication equipment connects two PBX extensions to the integrated digital communication network, and implements outgoing call, telephone call, and call termination by UUI service. Of the two extensions, one line is connected to the extension telephone communication terminal devices 15-1 and 15-2, and the other line is connected to an extension communication terminal device such as the facsimile communication device 15-3. It can be configured as connected.

1) Originating After detecting the calling signal from the PBX extension, the router 12 closes the loop by an automatic response, and when the preparation for receiving the PB dial is completed, the second dial tone “SRBT” is output to the PBX.
Send to extension. After receiving the dial signal from the PBX extension, the router 12 sets an inter-digit timeout or “#”.
After receiving the PB signal (excluding # in the first digit), it sends outgoing messages by the UUI service to the integrated digital communication network. When the Japanese switching center 3 receives the UUI data normally, the router 12 outputs the second call tone “SRBT”.
To the PBX extension. Also, if the call cannot be transmitted normally and the "BT" cannot be received from the integrated digital communication network, or if the "BT" is stopped after reception, "BT" is transmitted from the router 12 to the PBX extension. I do. 2) Transmission During the call, the router 12 transmits “BT” from the PBX extension side.
To monitor. 3) Termination After detecting "BT" from the PBX extension, the router 12 releases the loop and sends disconnection messages to the integrated digital network.

Next, the data elements of the UUI data will be described. The data elements of the UUI data of the present invention include an identification code, a control code, a data code, a member number, a password, a Japan switching center number, a callback number, and a management code (management number). , Destination number, and dial end identification. As the identification code, any one of download incoming call, download response, download reading, international call originating (sending), and international calling incoming (receiving) is selected.
As the control code, one of “ACK”, “NAK”, and a retransmission request that is an incoming call when the B channel is not available is selected. The data code is subdivided into an end code indicating the end of the data and a delimiter code indicating a data delimiter.

The management code characterizing the present invention is the router 1
2 is divided into groups connected to port 1 and port 2, and is updated and assigned sequentially for each transmission in each group. The member number, password, Japanese exchange center number, callback number, and dial end identification are backed up in the memory 132 of the router 12.

The download (incoming) data is data sent from the Japanese switching center 3 to the router 12 as a call setting, and includes an identification code, a management number, a member number, a password, a callback number, It consists of a local exchange center number, a dial end identifier, and an end code. The download (response) data is data transmitted from the router 12 to the Japanese switching center 3 as release completion. When there is no abnormality in the data of the download incoming call, the same data as the download (answer) data is returned to the Japanese exchange center 3 as the download (response) data. When there is an abnormality in the received download data (incoming call), and when there is no data in the router 12 or when the stored data is abnormal, the download (response) data returned to the Japanese exchange center 3 is ,
It consists of an identification code, a management number, and an end code.

The data format used for the service according to the present invention will be described below with reference to FIGS.
FIG. 5A shows the format of data at the time of download. The download (incoming) data and the download (response) data 500 include an identification code 501, a management number 502, a member number 503, a password 504, a callback number 505, and a Japanese exchange center number 506.
, A dial end identification 508, and an end code 509, and a delimiter is provided between each number code.

FIG. 5B shows a specific example of download (incoming) data. In the download (incoming) data, the identification code 501 is set to, for example, “11”.

FIGS. 5C and 5D show specific examples of download (response) data. The identification code 501 of the download (response) data is set to, for example, “13”. When the download (incoming) data is normal, the identification code 501 is set to “1” as shown in FIG.
The download (incoming) data replaced with “3” is returned to the Japanese responsiveness center 3 as download (response) data. Response data when there is an abnormality in the download (incoming) data is as shown in FIG. And identification code 5
01, a management number 502, and an end code 509, and the identification code is set to "13". If there is an abnormality in the received download data, the received download data is discarded and is not stored in the memory 132.

The download (read) data shown in FIG. 5 (E) is data that is issued when the call is set from the Japanese switching center 3 to the router 12 and the downloaded data is read, and the identification code 501 and the end code 509 are provided. For example, the identification code 501 is set to “12”. As a response to the download (read) data of the router 12, the content currently registered in the router 12 is transmitted to the Japanese exchange center 3 using the same format as the normal format of the download (response) data. Download (incoming) data, download (response)
In the data, dummy data “00” is selected as the management number data 502.

The following management number data transmitted / received for international call transmission indicates the analog port of the PBX 11 and the call origination. For example, the extension telephones 15-1 and 15-2
Is selected from "01" to "49", and the facsimile terminal device 15-3 is selected and assigned to any of "50" to "99". The management number is sequentially incremented for each call from the router 12. Are given by circulating in the same group. Once the router 12 has placed a call with a management number, the call is returned from the receiving switching center 5 to the call until the call is called back.
The assigned management number is the router 12-the Japanese exchange center 3
-Since the transfer is made between the receiving-side switching center 5 and the router 12, the incoming call is originated by comparing the administrative number given to the incoming call back with the administrative number given to the outgoing call. It is possible to recognize whether or not this is a callback for the called call. Further, after the extension communication terminal device 15 makes a call and the router 12 makes an international call, when the extension communication terminal device 15 abandons this waiting call and makes a new call, a new management number is assigned. Since it is provided, it is possible to determine whether or not the incoming call is for a newly-originated call, and to respond only to the call for the newly-originated call.

Next, a call setup and release completion data format for international calling will be described with reference to FIG. In international call setting, first, a call from the router 12 to the Japanese switching center 3 is set via the D channel of the public network 2 using the Japanese switching center number 506 downloaded to the router 12. The connection data is transferred as UUI data. At this time, the format of the connection setting connection data transferred is, as shown in FIGS. 6A and 6B, an identification code 601, a management number 602, a member number 603, a password 604, and a call number. Back number 60
5, a destination number 609, and an end code 608, and a delimiter is provided between the numbers.
The identification code 601 of the call setting data from the router 12 to the Japanese switching center 3 is set to, for example, “01”. As shown in FIG. 6C, the format of the release completion data sent from the Japanese switching center 3 to the router 12 includes an identification code 601 and an end code 609. The identification code 601 of the release completion data returned from the Japanese switching center 3 to the router 12 is “03” as shown in FIG. 6D for “NAK” and as shown in FIG. 6E for “NAK”. Is set to “04”.

FIG. 7 shows a format of the call setting data from the receiving side switching center 5 to the router 12 at the time of international calling. As shown in FIG. 7A, the call setting data at the time of receiving a call from the receiving-side switching center 5 to the router 12 includes an identification code 70
1, a management number 702, and an end code 708, and a delimiter is provided between the numbers. As shown in FIG. 7B, the identification code 701 of the call setting data at the time of the incoming call from the receiving side switching center 5 to the router 12 is set to, for example, “02”.

The response data format from the router 12 to the destination switching center 5 is composed of an identification code 701 and an end code 708 as shown in FIG. The identification code 701 in this case is “03” in “NAK”.
In the case of “NAK”, “04” is set.

When there is an incoming call from the receiving-side switching center 5 whose management number matches, and the B channel of the public telephone network on the Japanese side is not vacant, a request for re-originating this incoming call is made. FIG. 8 shows the format of the transmission request data. The retransmission request data 800 includes an identification code 801 and an end code 808. This identification code 801
Is set to “05”.

The determination process for an incoming call in the router 12 will be described with reference to the flowchart of FIG. Router 1
When there is an incoming call at 2, it is determined whether the reception of the UUI data is successful (S1). When the UUI data is successfully received, it is determined whether the received UUI data has a management number (S2). If there is a management number, it is determined whether the management number given to the outgoing call matches the received management number (S3). If the management numbers match, it is determined that this is a callback for the outgoing call from the receiving side switching center 5 and a response is sent back, and this incoming call is connected to the extension telephone 15 (S4). When the UUI data cannot be received in step S1, when the control number is not found in step S2, and when the control numbers do not match in step S3, the call back from the receiving side switching center 5 for the outgoing call is performed. It is determined that there is no incoming call, and the connection to the extension exchange 15 that originated the incoming call is refused.

The operation for making an international call from the extension telephone 15 in the above processing will be described with reference to FIG. The caller goes off-hook on the handset of the extension telephone 15 (S1).
1) When a dial tone (hereinafter referred to as DT) sent from the PBX 11 is heard (S12), the router 12
Is dialed (S13). When the caller listens to the STD from the router 12 (S14), the caller dials an international telephone number consisting of a country code and a telephone number of the other party (S15) and sends dial end information consisting of "*" or "#". The user dials (S16). While the UUI data is exchanged with the Japanese exchange center 3, "SRBT" is heard (S17). While the connection processing of the international communication network is performed between the Japanese switching center 3 and the receiving switching center 5, the extension communication terminal 15 is silent (S18). When the international communication network is connected and “RBT” is returned from the called-side network, the caller of the extension communication terminal 15 receives the “RBT”
Is heard (S19). When there is a response from the called party, the caller of the extension terminal device 15 starts talking (S20).
When the call ends, the telephone 15 is turned on to end the call operation (S21).

[0055]

As described above, according to the international telecommunications service utilization system of the present invention, the following advantages can be obtained.

(B) The international telecommunications service router corresponding to the dedicated adapter in the conventional method has a predetermined extension telephone number or a so-called special number as an automatic device for handling international communication services, and has a plurality of extension telephones. Can be called from Based on general usage, one or two routers may be installed for 100 extensions. Therefore, since one router handles a plurality of extension communication terminal devices, compared to the case where a dedicated adapter is installed in each telephone terminal device as in the related art,
The cost is reduced, the installation work of the special adapter is simplified, and the construction cost is also reduced.

(B) An ISDN line (NTT's ISN net 64) is used as a domestic communication line network. Especially,
In the present invention, an ID number and a password are transmitted as inter-user information using the inter-user information notification service.
This service is provided by NTT as a product name UUI, and is a function that allows a user to transmit and receive a certain amount of information to and from another user through a signal channel. The current communication fee is 1 message (128 octets)
Up to 0.4 yen and the monthly fee is free. Therefore, the communication cost for outgoing connection becomes extremely low. Also,
The communication charges for actual calls are cheap because international calls are made. Therefore, according to the system of the present invention, domestic call charges are low, call charges from a long distance are also low, and it is easy to use from a long distance.

(C) In the direct communication system using the current dedicated adapter, even if any international communication company is dialed, a connection is made to a cheap service center. On the other hand, in the method of the present invention, it can be used by the selection dial on the calling side.

(D) The system of the present invention has an additional advantage that its use can be extended to other digital services.

(E) In the present invention, data including a management number assigned to each call is transmitted to the Japanese switching center at the time of calling, and this management number is transferred until called back from the called switching center. It is possible to judge whether or not the callback for the outgoing call has been made by checking the correspondence between the outgoing control number and the received control number, thereby preventing an incorrect call from being connected to the extension in standby. it can.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of a communication system to which an international communication service using a gateway exchange according to the present invention is applied.

FIG. 2 is a block diagram showing a configuration of a router used in the present invention.

FIG. 3 is a functional block diagram showing a functional configuration of a router used in the present invention.

FIG. 4 is a process explanatory diagram illustrating an international communication connection processing procedure in a bargain international telecommunication service using the gateway exchange according to the present invention.

FIG. 5 is a view for explaining a data format used in a communication system using the gateway exchange according to the present invention.

FIG. 6 is a diagram illustrating a data format used in a communication system using the gateway exchange according to the present invention (part 1).

FIG. 7 is a diagram for explaining a data format used in a communication system using the gateway exchange according to the present invention (part 2).

FIG. 8 is a diagram (part 3) for explaining a data format used in a communication system using the gateway exchange according to the present invention.

FIG. 9 is a flowchart of a determination for an incoming call of a router.

FIG. 10 is a flowchart for explaining a caller's operation during a call.

FIG. 11 is a block diagram showing the concept of the configuration of a second embodiment of the present invention.

FIG. 12 is a block diagram showing an outline of a conventional system for using a low-cost international telecommunication service.

FIG. 13 is a block diagram showing an outline of an improved conventional undervalued international telecommunications service utilization system.

FIG. 14 is an exemplary view for explaining the procedure of call setting in the utilization system shown in FIG. 13;

FIG. 15 is a block diagram showing a configuration of a router used in the utilization system shown in FIG. 13;

[Explanation of symbols]

 1 User 2 Domestic Public Line Network (ISDN) 3 Japanese Switching Center (Gateway Switch) 4 International Communication Network (ISDN) 5 Terminating Switch Center (Gateway Switch) 6 Callee (Telephone) 7 ISDN Line 11 Automatic Private Branch Exchange (PBX) 12 Router 14 Digital Service Unit (DSU) 15 Extension Telephone Terminal 17 Trunk 19 Adapter

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masaaki Kimura 24-4 Sakuragaoka-cho, Shibuya-ku, Tokyo Inside Nakayo Communication Equipment Co., Ltd. SSI Consulting Co., Ltd.

Claims (3)

[Claims] 1. A plurality of extension communication terminals accommodated in a PBX, at least one router accommodated in the PBX and connected to a public line network, and an originator connected to the router via a public line network A communication system comprising a gateway exchange, a communication network, a destination gateway exchange connected to the originating gateway exchange via a communication network, and a destination communication terminal device connected to the destination gateway exchange. A gateway exchange used for a return call connection communication system in which a call is transmitted after waiting for a return call connection from a destination gateway exchange with respect to a communication transmission from an originating extension communication terminal device, wherein the originating gateway exchange is the router. Incoming from connection data transmitted using the UUI service between users Gateway exchange used for folding the call connection communication method characterized by having a function of extracting the gateway exchange, the function of transferring using a packet communication connection data received from the router to the destination gateway exchange. 2. The return call connection communication system according to claim 1, wherein the connection data includes a connection destination number, a return call connection destination number, and a management number given for each call operation from the extension communication terminal device. Gateway exchange used for 3. The gateway exchange used in the return call connection communication system according to claim 1, wherein the connection data transmitted from the router to the originating gateway exchange is transmitted via a D channel of an ISDN line.