WO2005050964A1

WO2005050964A1 - Voice gateway apparatus

Info

Publication number: WO2005050964A1
Application number: PCT/JP2003/014941
Authority: WO
Inventors: Takashi Tsutsui
Original assignee: Softbank Bb Corp.
Priority date: 2003-11-21
Filing date: 2003-11-21
Publication date: 2005-06-02
Also published as: AU2003284439A1; TW200518575A

Abstract

A voice gateway apparatus for allowing an IP telephone service to be easily introduced in an environment using a private telephone branch exchange. A communication system including the voice gateway apparatus (30) is generally constituted by a telephone terminal (10), a private telephone branch exchange (20), the voice gateway apparatus (30), a call agent (40), an IP network (7) and a public telephone line network (8). The voice gateway apparatus (30) functions to mutually connect station lines (9) coupled to the private telephone branch exchange (20), subscriber lines (4) and an xDSL modem (1) that transmits/receives digital signals by use of the subscriber lines (4). The voice gateway apparatus (30) further functions to perform transformations from voice band signals to IP packets and vice versa, and transmit/receive these voice band signals and IP packets.

Description

Description. Technical field of voice gateway device

The present invention relates to a voice gateway device for converting a voice band signal transmitted / received by a private branch exchange into an IP bucket passed through an IP network. Background art

In a company office, etc., in order to efficiently exchange and connect a large number of telephone terminals deployed in the premises of the office and the telephone line, a private branch exchange

(Private Branch eXchange) is generally installed.

For example, as shown in Fig. 7, a premises telephone exchange 20 is installed in the premises 100 of the business office, etc., and the telephone terminal 10 matches the communication conditions and electrical characteristics of the telephone terminal 10 It is connected to the private branch exchange 20 using the extension interface 22.

In addition, the subscriber line 4 is connected to a subscriber line exchange 80a installed by a telecommunications carrier providing a telephone service through the public telephone network 8, and the maintenance responsibility with the telecommunications carrier is resolved. Via a certain relay terminal 3, it is connected to the private branch exchange 20 using a local line interface 21 that matches the communication conditions and electrical characteristics of the subscriber line 4.

On the other hand, due to recent advances in communication technology and the development of the Internet, so-called IP telephone services, which have lower communication charges than telephone services using the public telephone network 8, have become widespread. Under such circumstances, users using the telephone service by the public telephone network 8 using the private branch exchange 20 have come to request the use of the IP telephone service. In order to use the private telephone exchange 20 to use the IP telephone service, high-speed digital transmission is performed by using a voice Guy device or a subscriber line 4 that converts voice band signals and IP buckets to and from each other. It is necessary to interpose an xDSL modem or the like to be realized between the private branch exchange 20 and the subscriber line 4 (see, for example, Japanese Patent Application Laid-Open No. 2002-112130 (No. 6-8) Page, Fig. 1-2).

However, conventional IP telephone service providing devices such as the above-mentioned voice gateway device and xDSL modem cannot connect a plurality of subscriber lines, which are common in an environment using a private branch exchange, so that private telephone exchanges cannot be established. There is a problem that it is not suitable for introduction into an environment using a machine.

Furthermore, in order to connect such a conventional IP telephone service providing device to a private branch exchange, an extension interface is installed in the private branch exchange instead of the central office interface to which the subscriber line was connected until then. The cost of purchasing the interface, and the cost of repairing or replacing the private branch exchange, depending on the line capacity of the private branch exchange. there were.

Also, the conventional IP telephone service providing apparatus can connect to both the public telephone line network and the IP network, but when communicating via the IP network, the public telephone line network is connected to the public telephone line network. When an incoming call is received via a public telephone line, the public telephone line network cannot be notified that the incoming call cannot be switched because of communication and the public telephone line There was a problem that the ring tone (RBT) continued to be transmitted to communication terminals such as terminals. In particular, in an environment where a private branch exchange is used, since the volume of incoming and outgoing calls is large, such a situation frequently occurs, which has become a serious problem.

Therefore, the present invention has been made in view of the above points, and It is an object of the present invention to provide a voice gateway device for easily introducing an IP telephone service in an environment using a switching device. Disclosure of the invention

A first feature of the present invention is a voice gateway device which is inserted between a subscriber line and a private branch exchange to convert a voice band signal transmitted and received by the private branch exchange into an IP bucket. , A subscriber line connection section that connects multiple subscriber lines, a station line connection section that connects a plurality of office lines connected to the private branch exchange, and an IP communication that is connected to an IP network that passes IP packets. Based on the telephone number of the communication destination received from the private branch exchange via the local line and the IP network connection part connecting the line, the voice band signal received from the private branch exchange via the local line Selects whether to convert to a bucket and send it to the IP communication line or to send the voice band signal to the subscriber line, and exchanges the office line with the IP communication line or the subscriber line. And the means.

According to this feature, since the voice gateway device connects a plurality of subscriber lines and the office line connected to the private branch exchange, it is easy to introduce an IP telephone service in an environment using the private branch exchange. Can be.

According to this feature, based on the telephone number of the communication destination received from the private branch exchange via the central office line, the audio gateway device converts the audio band signal received from the private local exchange via the local office line into an IP. Select whether to convert the packet to a bucket and send it out to the IP communication line or send the voice band signal to the subscriber line via the subscriber line connection unit, depending on whether it is an office line and an IP communication line or a subscriber. Since the connection to the line is exchanged, the public telephone line network and the IP network can be used properly according to the telephone number of the communication destination.

The second feature of the present invention is that when all the office lines are communicating, When an incoming call to the private branch exchange is received via the IP line or an incoming call to the private branch exchange via the IP communication path, the office line is communicating with the communication terminal that generated the incoming call. The main point is to have a busy notification means for notifying that the incoming call cannot be switched for connection.

According to a third feature of the present invention, in the second feature of the present invention, an incoming call to the private branch exchange is received via the subscriber line when the busy notification means S and all the office lines are communicating. In this case, a predetermined operation indicating that the line is communicating is performed on the network that has processed the incoming call, and the network responds to the communication terminal that generated the incoming call in accordance with the predetermined operation. The gist is to transmit a busy signal to notify that the incoming call cannot be switched because the line is busy.

According to this feature, the voice gateway device transmits a signal notifying that the local line is communicating to the network that has processed the incoming call, and the network responds to the signal in response to the signal. By transmitting a busy signal to the communication terminal that generated the incoming call to notify that the incoming line cannot be switched because the local line is busy, a private telephone via the subscriber line It is possible to reliably notify the communication terminal that has generated the incoming call to the exchange that it cannot respond because the office line is busy.

According to a fourth aspect of the present invention, in the second aspect of the present invention, a busy band notifying unit transmits a voice band signal to the communication terminal that has generated the incoming call, indicating that the office line is communicating. Therefore, the gist is to notify that the incoming call cannot be switched because the line is busy.

According to this feature, the voice gateway device transmits a voice band signal indicating that the office line is communicating to the communication terminal that has generated the incoming call. That the incoming call cannot be switched Therefore, it is possible to surely notify the communication terminal that the line cannot be responded because the office line is communicating.

According to a fifth aspect of the present invention, in the first to fourth aspects of the present invention, it is preferable that the central office connection unit connects to the private branch exchange using an interface that operates as a subscriber line. Make a summary.

According to this feature, since the voice gateway device connects to the private branch exchange using the interface operating as the subscriber line, the private gateway exchange connects the voice gateway device. The interface to which the subscriber line was previously connected can be continued to be used, and modification or replacement of the private branch exchange can be avoided.

According to a sixth aspect of the present invention, in the first to the alternate aspects of the present invention, the local line power is associated with a specific telephone number, and when the exchange means is communicating with the specific local line, When an incoming call is received for the telephone number associated with that station line, the point is to capture another station line not used for communication and exchange-connect the incoming call.

According to such a feature, when the voice gateway device receives an incoming call for the telephone number associated with the particular line while the particular line is communicating, the voice gateway apparatus is connected to the other line connected to the line. Since an unused office line is captured and the incoming call is switched, the incoming call can be processed efficiently.

According to a seventh feature of the present invention, in the first to sixth features of the present invention, when the IP network has a failure, the exchange means can connect the office line and the subscriber line regardless of the telephone number of the communication destination. The point is to exchange connection.

According to this feature, when the IP network fails, the voice gateway device switches and connects the office line and the subscriber line via the subscriber line connection unit. Telephone communication can be secured.

According to an eighth aspect of the present invention, in the first to seventh aspects of the present invention, In the event that the means does not operate properly, the point is to have a detour connection means that directly connects the subscriber line and the office line to enable telephone communication.

According to this feature, the voice gateway device enables telephone communication by directly connecting the subscriber line connected to the subscriber line connection unit and the office line connected to the office line connection unit. Even in the event of a failure of the voice gateway device, certain telephone communication can be secured. '' Brief description of the drawings

FIG. 1 is a schematic configuration diagram of a communication system including a voice gateway device according to an embodiment of the present invention.

FIG. 2 is a functional block diagram of the audio gateway device according to one embodiment of the present invention.

FIG. 3 is a connection operation diagram of the voice gateway device according to one embodiment of the present invention.

FIG. 4 is a communication sequence diagram of a communication system including a voice gateway device according to an embodiment of the present invention.

FIG. 5 is a communication sequence diagram of a communication system including a voice gateway device according to an embodiment of the present invention.

FIG. 6 is an operation flowchart of the communication system including the audio gateway device according to the embodiment of the present invention.

FIG. 7 is a schematic configuration diagram of a communication system including a conventional private branch exchange.

BEST MODE FOR CARRYING OUT THE INVENTION

(Overall Configuration of Communication System Including Voice Gateway Device According to One Embodiment) An audio gateway device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram showing a communication system including a voice gateway device 30 according to the present embodiment.

As shown in the figure, the communication system including the voice gateway device 30 according to the present embodiment includes a telephone terminal 10, a private branch exchange 20, a voice gateway device 30, and a call agent 40. , An IP network 7, and a public telephone network 8.

The telephone terminal 10 is a communication terminal capable of inputting / outputting and transmitting / receiving a voice band signal, and is connected to the private branch exchange 20.

The private branch exchange 20 has a function of connecting a plurality of telephone terminals 10 to a plurality of central office lines 9 connected to the voice gateway device 30 and exchanging the telephone terminal 10 with the central office line 9. are doing. In the present embodiment, the private branch exchange 20 is, for example, an FXS (Foreign Exchange Server) that can send and receive call and response signals and supply power to the telephone terminal 10 in the case of voice band signals. on) The telephone terminal 10 can be connected using the interface. The private branch exchange 20 uses an FX0 (Foreign Exchange Office) interface, which has signal conditions and electrical characteristics for connecting the subscriber line 4, for example. Can be connected.

The voice gateway device 30 connects the office line 9 connected to the private branch exchange 20, the subscriber line 4, and the xDSL modem 1 that transmits and receives digital signals using the subscriber line 4, and provides a voice band. It has functions to convert signals and IP packets to each other, and to transmit and receive voice band signals and IP packets. Note that the subscriber line 4 is connected to the voice gateway device 30 via the relay terminal 3 which is a maintenance responsibility disaggregation point with the communication service provider that provides the subscriber line 4. Also, xDSL modem 1 uses digital signals and voice band signals. Is connected to the subscriber line 4 via a splitter 2 that separates The xDSL modem 1 is, for example, an ADSL Asymmetric Digital Subscriber Line modem for ITU-T G.992.1 (G. DMT) or 992.2 (G. Lite). be able to.

The call agent 40 has a function of converting telephone numbers and IP addresses and processing telephone calls in the IP network 7 in order to provide telephone communication via the IP network 7.

In this embodiment, the call agent 40 can be realized by, for example, an MGC (Media Gateway Controller) defined by MEGACO (Media Gateway Control) / MGCP (Media Gateway Control Protocol). . In addition, the call agent 40 may be a SIP server specified by GATEKINO or Session Initiation Protocol (SIP) specified in ITU-T H.323.

The IP network 7 is a communication network based on TCP / IP for providing IP telephone services, and is a set facing the xDSL modem 1 connected to the splitter 2 and the voice gateway device 30. It is connected to the subscriber line 4 via a DSLAM5, a type xDSL modem.

In the present embodiment, for example, the Internet can be used for the IP network 7. The IP network 7 may be a dedicated closed network based on TCP / IP for providing an IP telephone service.

The public telephone line network 8 is a telephone line network (PSTN) using a circuit switching system, and connects the subscriber lines 4 using subscriber line switches 80a and 80b. The IP network 7 and the public telephone line network 8 are connected so as to be able to communicate with each other via an inter-network connection gateway 70a, 70b and a subscriber line exchange 80a, 80b. You. In addition, the inter-network connection gateways 70a, 70b and the subscriber line exchanges 80a, 80b are, for example, No. 7 common line signals defined in ITU-T. It is possible to send and receive signal information such as telephone numbers using the signal system. In the communication system including the voice gateway device 30 according to the present embodiment as described above, the telephone terminal 10 is connected to the telephone terminal 60 subscribed to the IP telephone service by the IP network 7 via the IP network 7. Telephone communication and telephone communication with a general subscriber telephone terminal 90 connected to the public telephone network 8 can be performed via the private branch exchange 20.

In addition, the telephone terminal 60 converts the voice band signal into an IP packet and executes a process of querying the call agent 40 for an IP address, a VoIP adapter 50, an xDSL modem 1, and a splitter 2. Is connected to the IP network 7 via.

Next, the configuration of the audio gateway device 30 according to the present embodiment will be described with reference to FIG. As shown in the figure, the voice gateway device 30 includes a subscriber line connection unit 31, a local line connection unit 32, an IP network connection unit 33, a Vo IP conversion unit 34, and a connection control unit. It has a unit 35, a voice response unit 36, a storage unit 37, and an external interface unit 38.

The subscriber line connection unit 31 has an interface that satisfies the signal conditions and electrical characteristics for connecting the subscriber line 4 and connects a plurality of subscriber lines 4. In the present embodiment, the subscriber line connection unit 31 is a signal for connecting to the subscriber line exchanges 80a and 80b via the subscriber line constituted by, for example, a telephone copper cable. The FX0 interface, which is a 2-wire interface that satisfies conditions and electrical characteristics, can be mounted.

The number of subscriber lines 4 to which the subscriber line connection unit 31 can be connected may be changed according to the scale of the private branch exchange 20 connected to the voice gateway device 30. In addition, the subscriber line connection unit 31 is connected to the subscriber line exchange 80a connected via the subscriber line 4 for signal conditions, electrical characteristics and subscribers. For example, a 4-wire interface may be mounted according to the configuration of the communication equipment interposed between the line 4 and the subscriber line switch 80a.

The office line connection section 32 has an interface that satisfies the signal conditions and electrical characteristics for connecting the office line 9 that can be connected to the private branch exchange 20 and connects a plurality of office lines 9. Things. In the present embodiment, for example, the office line connection unit 32 can mount an interface having signal conditions and electrical characteristics connectable to an FX0 interface mounted on the private branch exchange 20. .

Central office connection 3 2 Power S, Private telephone exchange 2 By installing an interface with signal conditions and electrical characteristics that can be connected to the FX0 interface mounted on the private branch exchange 20, 0 can connect and use the FX0 interface to which the subscriber line 4 was connected before connecting the voice gateway device 30.

The number of office lines 9 to which the office line connection unit 32 can be connected may be changed according to the scale of the private branch exchange 20 connected to the voice gateway device 30.

In the present embodiment, the IP network connection unit 33 connects the IP communication path 6 that enables communication using the TCP / IP protocol group via the IP network 7.

Specifically, the IP network connection unit 33 has an interface that can perform LAN communication, and transmits and receives IP packets to and from devices and the like that can perform LAN communication. Pokoo! It is possible to use 100BASE-TX, which is defined by 10BASE-I and 802.3u.

The IP network connection unit 33 according to the present embodiment is connected to the xDSL modem 1, and is connected to the IP network 7 via the subscriber line 4 composed of the splitter 2 and the telephone copper cable and the DSLAM 5. Connected to

The IP network connection unit 33 according to the present embodiment is connected to the xDSL modem 1. However, it may be connected to the IP network 7 via a subscriber line composed of an optical fiber using, for example, a media converter.

The Vo IP conversion section 34 converts the voice band signal transmitted and received by the line connection section 3 ′ 2 into and out of the IP bucket transmitted and received by the IP network connection section 33, and transmits the IP packet via the IP network 7. It adds headers and the like that are required for passing packets.

In the present embodiment, the VoIP converter 34 uses, for example, ITU-T G.811, which transmits at 64 kbits / s, and G.729 Annex-A, which transmits at 8 kbits / s. The audio band signal can be digitized, and the digitized audio band signal can be converted to an IP packet. Further, the VoIP conversion unit 34 can add a header to the contents of the IP packet (accordingly, a UDP or TCP header, or RTP (Real-time Transport Protocol)).

The connection control unit 35, based on the telephone number of the communication destination received from the private branch exchange 20 via the office line 9, converts the voice band signal received via the office line 9 into a VoIP conversion unit 34 In this case, the user selects whether to convert to an IP packet and send it to the IP network connection unit 33 or to the subscriber line connection unit 31. The connection control unit 35 has a function of switching and connecting the office line 9 with the IP communication line 6 or the subscriber line 4 based on the selection result.

Further, the connection control unit 35 has a function of converting an IP packet received via the IP network connection unit 33 into a voice band signal by the Vo IP conversion unit 34 and transmitting the signal to the office line 9. It has a function of sending out the voice band signal received from the subscriber line 4 via the subscriber line connection unit 31 to the local line 9.

Specifically, the connection control unit 35 is connected to the office line 9 and the IP network connection unit 33 or the subscriber line connection unit 31 based on the telephone number information registered in the storage unit 37. Can be switched and connected to subscriber line 4. The

As described above, since the connection control unit 35 determines the switching connection destination based on the telephone number information stored in the storage unit 37, the user of the telephone terminal 10 can use the IP network 7 or the public telephone network. The telephone service provided by the IP network 7 or the public telephone network 8 can be used without being aware of the choice of telephone communication via the telephone network 8. Furthermore, when a telephone number for which communication is not permitted is stored in the storage unit 37, the connection control unit 35 can also control the transmission of the telephone number.

In addition, when the office line 9 is associated with a specific telephone number, the connection control unit 35, when a certain office line 9 is in communication, transmits a telephone number associated with the office line 9 to the telephone number. When an incoming call is received, it has a function of capturing another station line 9 not used for communication and switching and connecting the incoming call.

For example, Figure 3 shows the office line 9a associated with "Phone number: 1 2 3 4-1 1 1 1" and the office line associated with "Phone number: 1 2 3 4—1 1 1 2" 9b shows a case where an incoming call destined for “telephone number: 1 2 3 4 — 1 1 1 1” is received in a state where communication is being performed by exchange connection by the connection control unit 35 and communication is being performed. The connection control unit 35 recognizes that the office line 9a associated with “telephone number: 1 2 3 4—1 1 1 1” is already communicating, and “phone number that is not used for communication” 1 2 3 4—1 1 1 3 ”, the subscriber line 4 that has received the incoming call can be exchanged with the local line 9c using the local line 9c.

Further, in the present embodiment, in the case where the line 9 and the IP communication line 6 are exchange-connected in the present embodiment, the IP address corresponding to the telephone number of the communication destination received via the line 9 is provided. In this embodiment, the connection control unit 35 can be used when the IP network 7 has a failure. Can exchange and connect the office line 9 and the subscriber line 4 irrespective of the telephone number of the communication destination received via the office line 9. The connection control unit 35 can determine a failure in the IP network 7 when, for example, communication with the call agent 40 cannot be established.

Note that, in the present embodiment, the VoIP conversion unit 34 and the connection control unit 35 constitute an exchange unit.

Further, in the present embodiment, when an incoming call to the private branch exchange 20 via the subscriber line 4 is received while all the office lines 9 are communicating in this embodiment, the connection control unit 35 An operation indicating that the line 9 is in communication with the processed network is performed, and the network transmits a busy signal to the communication terminal that generated the incoming call in accordance with the operation. Accordingly, it is possible to notify that the incoming call cannot be switched and connected because the local line 9 is busy. In this embodiment, the connection control unit 35 constitutes a busy notification unit.

When all of the office lines 9 are communicating, the connection control unit 35 communicates with other subscriber lines 4 which are not used for communication connected to the subscriber line connection unit 31 (idle state). When an incoming call to the private branch exchange 20 is received, for example, a number information transmission function (dial-in) or an outgoing telephone number reception function (number) which is an additional service of the telephone service provided by the public telephone network 8 Using the connection operation sequence used in 'display' to indicate that the local line 9 is communicating with the local exchanges 80a and 80b connected to the public telephone network 8. Can be.

Specifically, the connection control unit 35 uses the connection operation sequence used in the number information transmission function or the outgoing telephone number reception function to transmit the information from the subscriber line exchanges 80a and 80b. After returning a ringing signal (IR, etc.) or a primary response signal (DC loop) to the information receiving terminal activation signal (CAR), predetermined After a lapse of time, the loop of the subscriber line 4 receiving the incoming call is released. When the connection controller 35 releases the loop of the subscriber line 4 that has received the incoming call, the subscriber line exchanges 80a and 80b recognize that the office line 9 is communicating, and A busy tone (BT) can be transmitted to a communication terminal such as a telephone terminal that has generated the incoming call to the private branch exchange 20.

In addition, the connection control unit 35 transmits a voice band signal indicating that the station line 9 is communicating to the communication terminal that has generated the incoming call, so that the station line 9 is communicating. Therefore, it informs that the incoming call cannot be switched.

Specifically, in this embodiment, the connection control unit 35, when receiving an incoming call to the private branch exchange 20 via the subscriber line 4 while all the office lines 9 are communicating, In response to the incoming call, transmitting the talkie stored in the voice response unit 36 to the communication terminal that has generated the incoming call to notify that the line 9 is communicating. Can be. As a result, even when the additional services such as the number information transmission function and the outgoing telephone number reception function described above are not used, the connection control unit 35 can send the incoming call to the communication terminal that generates the incoming call. Can be informed that communication is in progress.

In addition, even when an incoming call to the private branch exchange 20 is received via the IP communication path 6, the connection control unit 35 responds to the incoming call and responds to the communication terminal that generated the incoming call. Alternatively, the talkie stored in the voice response unit 36 may be transmitted.

Further, in this embodiment, the connection control unit 3.5, when receiving an incoming call to the private branch exchange 20 via the IP network connection unit 33 when all the office lines 9 are communicating, the call agent A signal notifying that the station line 9 is communicating with the host 40 can be transmitted. Call Agent 4 0 indicates that, based on the notification from the connection control unit 35, the telephone number transmitted by the communication terminal is communicating with the VoIP adapter 50 to which the communication terminal that caused the incoming call is connected. Can be notified.

In the present embodiment, if the function of switching connection between the office line 9 and the IP communication path 6 or the subscriber line 4 does not operate normally, the connection control unit 35 Direct connection with line 9 constitutes detour connection means that enables telephone communication.

Specifically, the connection control unit 35 establishes a connection between the subscriber line 4 and the central office line when the switching connection function does not operate normally due to, for example, a failure in the power supply supplied to the voice gateway device 30. 9 so that voice band signals can be communicated with each other so that the switching connection function of the connection control unit 35 is not interposed.

The voice response unit 36 sends out a talk key indicating that the station line 9 is communicating in response to an instruction from the connection control unit 35.

The voice response unit 36 according to the present embodiment stores, for example, a voice message such as "The telephone is busy at the moment ..." and sends the voice message in response to an instruction from the connection control unit 35. be able to. The voice response unit 36 stores an arbitrary voice message input using the telephone terminal 10 in the voice response unit 36, and stores the stored voice message in the connection control unit. It can also be sent in response to an instruction from 35.

In addition, while the voice response unit 36 sends a talk key indicating that the line 9 is communicating to a communication terminal such as a telephone terminal that has generated an incoming call to the private branch exchange 20, any When the communication using the local line 9 is completed, the connection control unit 35 can exchange-connect the incoming call using the local line 9.

The storage unit 37 performs telephone communication via the IP network 7 or the public telephone line network 8. The telephone number of the communication destination to be stored is stored.

In the present embodiment, the storage unit 37 can store a telephone number to perform telephone communication via the public telephone network 8 and a telephone number for which communication is not permitted. The storage unit 37 stores an arbitrary telephone number such as an area code + a city code + a subscriber number, an area code + a city code, an area code, a country code, or a block of a telephone number. be able to. It should be noted that a specific identifier is given to a telephone number for which communication is not permitted, and the connection control unit 35 can make a determination when making an exchange connection.

Further, the storage unit 37 can temporarily store an IP address or the like received from the call agent 40 and associated with the telephone number of the communication destination.

The external interface unit 38 provides a communication interface for connecting an external device in order to register a telephone number in the storage unit 37 and make settings for the voice gateway device 30.

In the present embodiment, the external interface unit 38 has, for example, an RS-232C interface, and can be connected to a PC or the like. The registration of the telephone number in the storage unit 37 and the setting for the voice gateway device 30 can be performed by a PC or the like connected to the external interface unit 38.

(Operation of the communication system described above)

The operation of the above communication system will be described with reference to FIGS. FIG. 4 is a communication sequence diagram in the case of making a call to the telephone terminal 60 in the communication system according to the present embodiment.

When the telephone number assigned to the telephone terminal 60 is input from the telephone terminal 10, the input telephone number is transmitted from the telephone terminal 10 to the private branch exchange 20 (S <b> 40). 1).

The private branch exchange 20 exchanges and connects the telephone terminal 10 with the office line 9 and The telephone number received from the telephone terminal 10 is transmitted to the gateway device 30 (S403).

The voice gateway device 30 determines that the telephone number received from the private branch exchange 20 should communicate via the IP network 7 based on the telephone number information stored in the voice gateway device 30. The call agent 40 inquires the IP address corresponding to the telephone number to the call agent 40 (S405). The call agent 40 notifies the VoIP adapter 50 connected to the telephone terminal 60 of the incoming call. Yes (S407).

The VoIP adapter 50 recognizes an incoming call from the call agent 40, inverts the polarity of the line with the telephone terminal 60, and sends a call signal to the telephone terminal 60 (S409) .

When the handset of telephone terminal 60 goes up (off-hook), telephone terminal 60 loops the line with VoIP adapter 50 and answers the call from call agent 40 (S 4 1 1).

The VoIP adapter 50 notifies the call agent 40 of the port number used for the communication connection with the voice gateway device 30 and that the telephone terminal 60 has responded (S413).

The call agent 40 notifies the voice gateway device 30 of the IP address assigned to the VoIP adapter 50 and the port number notified from the VoIP adapter 50 (S 415 ).

The voice gateway device 30 communicates with the VoIP adapter 50 based on the IP address assigned to the VoIP adapter 50 notified from the call agent 40 and the port number used for the communication connection. Request the setting of the communication connection (S417).

The VoIP adapter 50 sets a communication connection in response to a request for setting a communication connection from the audio gateway device 30 (S 419). The voice gateway device 30 receives the communication connection set in steps S 417 and S 419 and the telephone number assigned to the telephone terminal 60 in step S 403. Exchange connection with line 9 (S 4 2 1).

In addition, the Vo IP adapter 50 connects the telephone terminal 60 so as to be able to communicate using the communication connection set in step S 417 and step S 419 (S 423) .

The communication between the telephone terminal 10 and the telephone terminal 60 is started by the completion of the processing of step S421 and step S432 (S425).

FIG. 5 is a communication sequence diagram in the case of making a call to the telephone terminal 10 and the general subscriber telephone terminal 90 in the communication system according to the present embodiment.

When the telephone number assigned to the general subscriber telephone terminal 90 is inputted from the telephone terminal 10, the inputted telephone number is transmitted from the telephone terminal 10 to the premises telephone exchange 20. (S501).

The private branch exchange 20 exchanges and connects the telephone terminal 10 with the office line 9 connected to the voice gateway device 30, and sends the telephone number received from the telephone terminal 10 to the voice gateway device 30. Yes (S503).

The voice gateway device 30 determines, based on the telephone number information stored in the voice gateway device 30, that the telephone number received from the private branch exchange 20 should communicate via the IP network 7. Then, the call gateway 40 inquires the IP address corresponding to the telephone number to the call agent 40 (S505). The voice gateway device 30 transmits the telephone number received from the private branch exchange 20 to the public telephone line network. If the communication is to be performed via 8, the telephone number is sent to the local exchange 80a.

Call agent 40 received from voice gateway device 30 It recognizes that the telephone number is a general subscriber telephone terminal that subscribes to the telephone service provided by the public telephone network 8, and transfers the telephone number to the inter-network connection gateway 70b (S50). 7).

The network connection gateway 70b notifies the subscriber line exchange 80b of the telephone number transferred from the call agent 40 by a common line signal (S509).

The subscriber line exchange 80b reverses the polarity of the line with the general subscriber telephone terminal 90 based on the telephone number notified from the network connection gateway 70b, and And sends a calling signal (S511). -When the receiver of the general subscriber telephone terminal 90 goes up (off-hook), the general subscriber telephone terminal 90 loops the line with the local exchange 80b, and starts from the local exchange 80b. Answer the call (S5 13).

The subscriber line exchange 80b notifies the internet connection gateway 70b by a common line signal that the general subscriber telephone terminal 90 has answered the call (S515).

When the subscriber line exchange 80b notifies that the general subscriber telephone terminal 90 has answered the call, the internetwork gateway 70b sends the voice gateway device 3 to the call agent 40. The port number used for the communication connection with 0 is notified (S5 17).

The call agent 40 notifies the voice gateway device 30 of the IP address assigned to the network connection gateway 70b and the port number notified from the network connection gateway 70b ( S5 19).

The voice gateway device 30 establishes an inter-network connection based on the IP address given to the inter-network connection gateway 70 b notified from the call agent 40 and the port number used for the communication connection. It requests the gateway 70b to set the communication connection (S521). The network connection gateway 70b sets a communication connection in response to a request for setting a communication connection from the voice gateway device 30.

(S 5 2 3).

The voice gateway device 30 receives the communication connection set in Steps S521 and S523 and the central office that has received the telephone number assigned to the general subscriber telephone terminal 90 in Step S503. 9 and exchange connection (S5 25).

In addition, the inter-network connection gateway 70b uses the communication connection set in steps S521 and S523 to connect to the general subscriber telephone terminal via the subscriber line switch 80b. 90 is communicably connected (S527).

Upon completion of the processing in steps S525 and S527, communication between the telephone terminal 10 and the general subscriber telephone terminal 90 is started (S529). Next, an operation of processing an incoming call to the voice gateway device 30 according to the present embodiment will be described with reference to FIG.

The voice gateway device 30 receives an incoming call from the IP network 7 or the public telephone line network 8 (S601).

The voice gateway device 30 checks whether there is a station line 9 not used for communication (S603).

If there is a station line 9 not used for communication, the voice gateway device 30 exchanges and connects the station line 9 with the subscriber line 4 or the IP communication line 6 that has received the incoming call (S60) Five ) .

When all the office lines 9 are communicating, the voice gateway device 30 determines whether the call is an incoming call from the IP network 7 or the public telephone line network 8 (S607).

In the case of an incoming call from the IP network 7, the voice gateway device 30 A signal is sent to the agent 40, notifying that the incoming call cannot be switched because all the office lines 9 are communicating (S609). When the voice gateway device 30 notifies the call agent 40 that the incoming call cannot be switched and connected, the call agent 40 is connected to the communication terminal that has generated the incoming call. The VoIP adapter 50 can be notified that the telephone number transmitted by the communication terminal is communicating.

Next, in the case of an incoming call from the public telephone network 8, the voice gateway device 30 returns a primary response signal (DC loop) to the subscriber line 4 that has received the incoming call ( S 6 1 1).

Here, the voice gateway device 30 performs different operations depending on whether the number information transmission function (dial-in) or the outgoing telephone number reception function (number display) is used (S613). .

When the number information sending function or the outgoing telephone number receiving function is not used, the voice gateway device 30 responds to the incoming call and establishes a communication path with the communication terminal that has generated the incoming call ( S 6 15).

Using the communication path established in step S615, the voice gateway device 30 sends a voice message to the effect that the station line 9 is not communicating and cannot be connected to the communication terminal that generated the incoming call. To be transmitted (S6 17).

When the number information transmission function or the outgoing telephone number reception function is used, the voice gateway device 30 transmits the primary response signal after a predetermined time has elapsed from returning the primary response signal in step S611. The loop of the subscriber line 4 generated to return the signal is released (S619).

When the voice gateway device 30 executes the operation of step S 6 19, the subscriber line switch 80 a connected to the subscriber line 4 is activated. It recognizes that the incoming call cannot be exchanged and connected because all the office lines 9 connected to the voice gateway device 30 are communicating, and issues a busy tone (BT) to the communication terminal that generated the incoming call. Can be sent. (Operation and effect of the audio gateway device according to the present embodiment)

According to the voice gateway device 30 according to the present embodiment, since the voice gateway device 30 connects the plurality of subscriber lines 4 and the office line 9, the number of necessary voice gateway devices 30 is reduced, and The space can be reduced, and the work of installing the voice gateway device 30 can be facilitated. Also, according to the voice gateway device 30 according to the present embodiment, the signal line conditions and electrical characteristics that can be connected to the office line connecting unit 32 and the FX0 interface mounted on the private branch exchange 20 are provided. The private branch exchange 20 can continue to use the FX0 interface to which the subscriber line 4 was connected before connecting the voice gateway device 30 because of the implementation of the interface with It becomes. By using such a voice gateway device 30, it is possible to use the IP telephone service at a low installation cost while avoiding the additional cost for the private branch exchange 20, and expand the use of the IP telephone service. Can be contributed to.

Further, according to the voice gateway device 30 according to the present embodiment, the connection control unit 35 determines the exchange connection destination based on the telephone number information stored in the storage unit 37, Users of the telephone terminal 10 can use the telephone service provided by the IP network 7 or the public telephone network 8 without being aware of the choice of telephone communication via the IP network 7 or the public telephone network 8. Priority can be given to IP telephone services with low communication charges.

Further, according to the voice gateway device 30 according to the present embodiment, the connection control unit 35 is connected to the subscriber line connection unit when all the office lines 9 are communicating. 3 When an incoming call to the private branch exchange 20 is received via another subscriber line 4 that is not used for communication connected to 1 (idle state) 4, the public telephone network 8 By using the supplementary service of the provided telephone service, it is possible to indicate to the public telephone network 8 that the office line 9 is communicating. As a result, even when an incoming call to the private branch exchange 20 is received via the subscriber line 4 while all the office lines 9 are communicating, the public telephone network 8 will It is possible to reliably notify the communication terminal such as the terminal that the incoming call cannot be answered because the office line 9 is communicating.

Further, according to the voice gateway device 30 according to the present embodiment, the connection control unit 35 transmits a voice response unit 36 to a communication terminal such as a telephone terminal that has generated an incoming call to the private branch exchange 20. It is possible to notify that the station line 9 is communicating by the talkie stored in the. As a result, even when the additional services such as the number information transmission function and the outgoing telephone number reception function described above are not used, the voice gateway device 30 can communicate with the communication terminal such as the telephone terminal that generated the incoming call. It is possible to reliably notify that the incoming call cannot be answered because the office line 9 is communicating.

Further, according to the voice gateway device 30 according to the present embodiment, when the IP network 7 has a failure, the connection control unit 35 receives the communication destination received from the private branch exchange 20 via the office line 9. Regardless of the telephone number of the subscriber line, the central office 9 and the subscriber line 4 are switched and connected via the subscriber line connection unit 31.

Furthermore, according to the voice gateway device 30 according to the present embodiment, when the function of switching and connecting the office line 9 with the IP communication line 6 or the subscriber line 4 does not operate normally, the connection control unit 35 allows telephone communication by directly connecting the subscriber line 4 to the office line 9.

As a result, the voice gateway device 30 according to the present embodiment is And the connection control unit 35, etc., it is possible to provide telephone communication via the public telephone network 8 via the subscriber line 4, thereby improving the operation rate of the voice gateway device 30. be able to. Industrial applicability

As described above, according to the present invention, it is possible to provide a voice gateway device for easily introducing an IP telephone service in an environment using a private branch exchange.

Claims

The scope of the claims

1. A voice gateway device that is inserted between a subscriber line and a private branch exchange to convert a voice band signal transmitted and received by the private branch exchange into an IP bucket,

A subscriber line connection unit for connecting the plurality of subscriber lines,

An office connection unit that connects a plurality of office lines connected to the private branch exchange, an IP network connection unit that connects an IP communication path connected to an IP network that communicates the IP packets,

Based on the telephone number of the communication destination received from the private branch exchange via the office line, the voice band signal received from the private branch exchange via the office line is converted into the IP bucket and converted to the IP packet. Switching means for selecting whether to send the signal to a communication path or to send the voice band signal to the subscriber line, and switching and connecting the office line to the IP communication path or the subscriber line. An audio gateway device characterized by the following.

2. When an incoming call to the private branch exchange is received via the subscriber line while all the office lines are communicating, or an incoming call to the private telephone exchange is received via the IP communication line. In this case, the communication terminal which has generated the incoming call has a busy notification means for notifying that the incoming call cannot be switched and connected because the central office is communicating. An audio gateway device as described.

3. The busy notification means, when receiving an incoming call to the private branch exchange via the subscriber line while all of the office lines are communicating, to a network that has processed the incoming call. Perform a predetermined operation indicating that the line is communicating,

The network responds to the communication terminal that originated the incoming call according to the predetermined operation. 3. The voice gateway device according to claim 2, wherein by transmitting a communication busy signal, it is notified that said incoming call cannot be switched and connected because said office line is busy.

4. The busy notification unit transmits a voice band signal indicating that the office line is communicating to the communication terminal that has generated the incoming call, whereby the office line is communicating. 3. The voice gating apparatus according to claim 2, wherein the notification that the incoming call cannot be exchanged and connected cannot be performed.

5. The office line connection unit according to claim 1, wherein the office line connection unit connects to the private branch exchange using an interface that operates as the subscriber line side. Voice gateway device.

6. The office line is associated with a specific telephone number, and the exchange means, when the specific office line is communicating, receives an incoming call for the telephone number associated with the office line. 6. The voice gaming device according to claim 1, wherein when receiving the voice call, the other incoming call line not used for communication is captured and the incoming call is exchanged and connected. Tway equipment.

7. The switching means, when the IP network has a failure, switches and connects the office line and the subscriber line regardless of the telephone number of the communication destination. The voice gateway device according to any one of claims 1 to 6.

8. The method according to claims 1 to 7, further comprising a bypass connection means for directly connecting the subscriber line and the central office line to enable telephone communication when the switching means does not operate normally. The voice gateway device according to claim 1.