JP4590302B2 - VoIP gateway device and call relay method - Google Patents

Description

  The present invention relates to a VoIP gateway device that relays a call between a telephone line and a VoIP (Voice over IP) network.

  A VoIP gateway device is known as a device for connecting an existing PBX or telephone to a VoIP network and receiving an IP telephone service. The VoIP gateway device receives a call signal and a control signal from an existing PBX (Private Branch Exchange) or a telephone, converts them into a VoIP packet and sends it to the VoIP network, or receives a VoIP packet from the VoIP network and receives a call signal. Or the control signal is restored and sent to the PBX or telephone (for example, see Patent Document 1).

JP 2003-298660 A

  In order to construct an extension telephone system that covers between geographically distant points, it has been conventionally performed to connect PBXs installed at each point by a dedicated line. In such an extension telephone system, the VoIP gateway device described above is installed at each point, and the PBX at each point is connected to the VoIP network via the VoIP gateway device at the point, and an IP phone service is provided for each extension number. By joining, an extension telephone system using a VoIP network instead of a dedicated line can be constructed.

  The internal telephone system using this VoIP network is generally considered to be able to reduce the operating cost compared to the case where a dedicated line is used. However, since it is necessary to subscribe to the IP telephone service for each extension number, the operation cost increases as the number of extension numbers increases. In addition, since a contract number (IP telephone number) for IP telephone service is newly assigned to each extension telephone number, it is necessary to change the numbering plan registered in the PBX.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to connect the PBX to the VoIP network without changing the numbering plan set in the PBX in the VoIP gateway device. To provide technology. Another object of the present invention is to provide a technology that can distribute incoming calls to a plurality of telephones accommodated by a PBX using a single IP telephone number.

  In order to solve the above problems, in the present invention, when an incoming call comes from the VoIP network, dial information is received in response, a route is specified according to the dial information, and the route is received.

For example, a first aspect of the present invention is a VoIP gateway device that relays a call between a telephone line interface accommodating a plurality of telephone lines and a VoIP network interface connected to the VoIP network,
For each dial information, incoming dial information storage means storing route information indicating a telephone line for receiving a call;
Dial information detection means for detecting dial information in response when an incoming call is received from the VoIP network via the VoIP network interface;
An incoming call that causes a call to be received via the telephone line interface to the telephone line indicated by the route information stored in the incoming dial information storage means in association with the dial information detected by the dial information detecting means. Control means.

  In the present invention, when dial information is received from the telephone line, the IP telephone number assigned to the dial information is specified, a call having the specified IP telephone number as the called number is sent to the VoIP network, and the other party answers. If so, the dial information is transmitted.

For example, a second aspect of the present invention is a VoIP gateway device that relays a call between a telephone line interface accommodating a telephone line and a VoIP network interface connected to the VoIP network,
For each dial information, a dial information storage means for outgoing call storing an IP telephone number assigned to the dial information;
When dial information is received from a telephone line via the telephone line interface, a call having an IP telephone number associated with the dial information and stored in the outgoing dial information storage means as a called number is called Outgoing call control means for transmitting to the VoIP network via the VoIP network interface and establishing a call path with a call partner having the IP telephone number;
Dial information sending means for sending dial information received from the telephone line via the telephone line interface to the communication path established by the call control means;

  According to the present invention, the PBX can be connected to the VoIP network without changing the numbering plan set for the PBX. In addition, incoming calls to a plurality of telephones accommodated by the PBX can be distributed using one IP telephone number.

  Embodiments of the present invention will be described below.

  FIG. 1 is a schematic diagram of an IP extension telephone system to which an embodiment of the present invention is applied.

  As shown in the figure, the IP extension telephone system of this embodiment includes a plurality of PBXs 2 that accommodate at least one extension telephone 3 and a plurality of VoIP-GWs (gateways) that connect at least one PBX 2 to the VoIP network 5. Device 1. The VoIP network 5 is also connected to a VoIP terminal (IP telephone) 4 other than the VoIP-GW apparatus 1 constituting the IP extension telephone system of this embodiment. Here, each extension telephone 3 is assigned the extension number shown in FIG. 1, each PBX 2 is assigned the station number shown in FIG. 1, and each VoIP-GW apparatus 1 and IP telephone 4 are shown in FIG. It is assumed that the IP telephone number shown is assigned.

  The IP extension telephone system of the present embodiment is an extension telephone system that is originally constructed by connecting PBXs 2 installed at geographically distant points with a dedicated line. 1 is installed, and the PBX 2 at each point is connected to the VoIP network 5 via the VoIP-GW apparatus 1 at the point, so that the VoIP network 5 is used instead of the dedicated line. It is assumed that the numbering plan of each PBX 2 has not been changed from that when it was connected to another PBX 2 via a dedicated line.

  When the VoIP-GW apparatus 1 receives dial information (a combination of a station number and an abbreviated dial of an extension number) from the PBX 2 accommodated by the VoIP-GW apparatus 1, the VoIP-GW apparatus 1 accommodates the PBX 2 having the station number included in the dial information. -The IP telephone number of the GW apparatus 1 is specified, and a call having the IP telephone number as the called number is sent to the VoIP network 5. When the call partner having the IP telephone number answers, the dial information is notified to the call partner using the call path established by the response.

  In addition, when a call arrives from the VoIP network 5, the VoIP-GW apparatus 1 responds and receives dial information from the other party. Then, the route (line) to be received is specified according to the station number included in the dial information, and the specified route is received. Further, the extension number corresponding to the abbreviated dial included in the dial information is specified, and the extension number is transmitted to the path where the call is received. If dial information is not sent from the call partner even after a predetermined time has elapsed after the response, voice guidance that prompts the user to input dial information is transmitted to the call partner.

  FIG. 2 is a schematic diagram of the VoIP-GW apparatus 1 shown in FIG.

  As shown in the figure, a VoIP-GW apparatus 1 of the present embodiment includes a line IF (interface) unit 11, an IP network IF unit 12, an RTP (Real-time Transport Protocol) processing unit 13, and a SIP (Session Initiation Protocol). ) A processing unit 14, a transmission control unit 15, an incoming call control unit 16, a PB transmission unit 17, and a PB detection unit 18.

  The line IF unit 11 is connected to a line for each PBX 2 accommodated by the own apparatus 1 and transmits / receives a call signal and a control signal to / from each PBX 2 accommodated by the own apparatus 1 via each line.

  The IP network IF unit 12 transmits and receives VoIP packets to and from the VoIP network 5.

  The RTP processing unit 13 receives a call signal received from the PBX 2 via the route channel notified from the outgoing call control unit 15 or the incoming call control unit 16 and a call partner having an IP address notified from the SIP processing unit 14. A process defined in RTP is performed on the received RTP packet.

  Specifically, a call signal is received from the channel of the route notified from the call control unit 15 or the call control unit 16 via the line IF unit 11, and the call signal is converted into an RTP packet. The IP address notified from the SIP processing unit 14 is transmitted to the VoIP network 5 from the IP network IF unit 12 as a destination. In addition, an RTP packet having the IP address notified from the SIP processing unit 14 as a source is received via the IP network IF unit 12, a call signal is restored from the RTP packet, and the restored call signal is transmitted to the line. It transmits to the channel of the route notified from the transmission control unit 15 or the incoming call control unit 16 via the IF unit 11.

  The SIP processing unit 14 performs a VoIP call control procedure defined in SIP in cooperation with a SIP server (not shown), and establishes a call with the other party.

  The transmission control unit 15 has transmission dial information TL (table) 151. As shown in FIG. 3, in the dialing information TL 151 for transmission, a record 1510 having a field 1511 for registering a station number and a field 1512 for registering an IP telephone number is registered for each dial information. The outgoing call control unit 15 uses the outgoing dial information TL 151 to control outgoing processing from the PBX 2 accommodated in the own device 1 to the VoIP network 5.

  The incoming call control unit 16 includes incoming dial information TL (table) 161. As shown in FIG. 4, the incoming dial information TL 161 includes, for each dial information, a field 1611 for registering dial information, a field 1612 for registering a route (PBX 2) for receiving a call, and a dial information number editing condition. A record 1610 having fields 1613 and 1614 for registering. In the example shown in FIG. 4, a field 1613 for registering the number of digits to be deleted from the head (upper digit) and a field 1614 for registering a number added to the head are used as the fields 1613 and 1614 for registering the number editing conditions. The incoming call control unit 16 uses the incoming dial information TL 161 to control incoming processing from the VoIP network 5 to the PBX 2 accommodated in the own device 1.

  The PB sending unit 17 generates a PB (Push Button) signal representing the dial information notified from the transmission control unit 15, and the RTP processing unit 13 uses the IP address notified from the transmission control unit 15 as the destination address. Notify

  The PB detection unit 18 detects a PB signal from a call signal restored from an RTP packet having the IP address notified from the incoming call control unit 16 as a transmission source address, and transmits dial information represented by the detected PB signal to the incoming call control unit 16. Notice.

  The VoIP-GW apparatus 1 described above is connected to, for example, a CPU 61, a program memory 62 in which a program is stored, a data memory 63 in which data is stored, an ISDN line, an OD line, etc., as shown in FIG. Then, a telephone line IF 64 that communicates with the PBX 2 via the line, a network IF 65 that communicates with the VoIP network, for example, is connected to the LAN cable, and these components 61 to 65 are interconnected via the cable. In the computer system having the internal bus 66, the CPU 61 executes the program stored in the program memory 62. In this case, the data memory 63 is used for each TL 151, 161, the telephone line IF 64 is used for the line IF unit 11, and the network IF 65 is used for the IP network IF unit 12.

  Next, the operation of the VoIP-GW apparatus 1 having the above configuration will be described.

  FIG. 6 is a flowchart for explaining the schematic operation of the VoIP-GW apparatus 1.

  When a SETUP message arrives from the PBX 2 accommodated in the own apparatus 1 to the line IF unit 11 (PBX 2 is the calling side) (Yes in S101), a transmission control process described later is performed (S103). Further, when the IP network IF unit 12 receives the INVITE message (PBX 2 is the incoming side) (No in S101, Yes in S102), incoming call control processing described later is performed (S104).

  FIG. 7 is a flowchart for explaining the transmission control process S103 of FIG.

  First, the line IF unit 11 notifies the call control unit 15 of the called number specified by the SETUP message (S10301). In response to this, the transmission control unit 15 refers to the dialing information for outgoing call TL151, and whether or not the upper n digits (2 digits in the example shown in FIG. 3) of the called number are registered as the station number in the outgoing dialing information TL151. (S10302).

  If the upper n digits of the called number are registered as the station number in the dialing dial information TL 151 (YES in S10302), this SETUP message is directed to one of the extension telephones 3. In this case, the process proceeds to S10303. On the other hand, when the upper n digits of the called number are not registered as the station number in the dialing dial information TL 151 (NO in S10302), this SETUP message is directed to a VoIP terminal (external line) other than the extension telephone 3. In this case, the process proceeds to S10308.

  In the present embodiment, when a user of an extension telephone 3 makes a call to another extension telephone 3, the other extension telephone is added to the head of the speed dial assigned to the extension number of the other extension telephone 3. A number to which the station number of PBX 2 accommodating 3 is added is input as the called number. Here, the abbreviated number is the lower two digits of the extension number. For example, in FIG. 1, when calling the extension telephone 3 with the extension number “3001”, the extension telephone 3 with the extension number “3001” is connected to the speed dial “01” specified by the lower two digits of the extension number “3001”. The number “5601” obtained by adding the station number “56” of the PBX 2 to be accommodated is input as the called number.

  On the other hand, in the present embodiment, when a user of the extension telephone 3 calls a VoIP terminal other than the extension telephone 3, the user inputs the IP telephone number assigned to the VoIP terminal as a called number. For example, when a call is made to IP phone 4, the IP phone number [05035456789] of the IP phone 4 is input as the called number.

  In S10303, the transmission control unit 15 identifies the record 1510 having the field 1511 in which the upper n digits of the called number are registered as the station number from the transmission dial information TL151, and stores the field 1512 in the identified record 1510. Get registered IP phone number. Then, the IP telephone number is notified to the SIP processing unit 14 and a call is instructed. In response to this, the SIP processing unit 14 generates an INVITE message with the IP telephone number received from the call control unit 15 as the destination number (called number), and this INVITE message is sent to the VoIP network via the IP network IF unit 12. 5 (S10304). This INVITE message is transferred via a SIP server (not shown) to the VoIP-GW apparatus 1 connected to the PBX 2 that accommodates the other party (extension telephone). Then, the VoIP-GW apparatus 1 transmits a response message (200 OK) to the own apparatus 1. Thereafter, the SIP processing unit 14 performs a call control procedure according to SIP with the VoIP-GW apparatus 1 that has transmitted the response message, and establishes a call with the VoIP-GW apparatus 1 (S10305). .

  Next, the SIP processing unit 14 notifies the RTP processing unit 13 and the transmission control unit 15 of the IP address of the VoIP-GW device 1 for which a call has been established with the own device 1. The transmission control unit 15 notifies the PB transmission unit 17 of the called number identified from the SETUP message in S10301. The PB sending unit 17 generates a PB signal representing the called number received from the call control unit 15, adds the IP address received from the SIP processing unit 14 to the PB signal, and notifies the RTP processing unit 13 of the PB signal. In response to this, the RTP processing unit 13 generates an RTP packet storing the PB signal, and sends the RTP packet from the IP network IF unit 12 to the VoIP network 5 with the IP address added to the PB signal as the destination. It is sent out (S10306).

  Next, the outgoing call control unit 15 sends route information indicating the line connected to the PBX 2 that is the transmission source of the SETUP message and channel information indicating the call channel specified by the SETUP message to the RTP processing unit 13. Notice. In response to this, the RTP processing unit 103 determines the channel specified by the channel information notified from the transmission control unit 15 of the line specified by the route information notified from the transmission control unit 15 by the line IF unit 11. The RTP packet received from the VoIP-GW apparatus 1 having the IP address notified from the SIP processing unit 14 by the IP network IF unit 12 and the call signal received from the PBX 2 via the PBX 2 (S10307). Thereby, a telephone call becomes possible.

  On the other hand, in S10308, the outgoing call control unit 15 specifies the called number as an IP telephone number, notifies the SIP processing unit 14 of the specified IP telephone number, and instructs the outgoing call. In response to this, the SIP processing unit 14 generates an INVITE message with the IP telephone number received from the call control unit 15 as the destination number (called number), and this INVITE message is sent to the VoIP network via the IP network IF unit 12. 5 (S10309). This INVITE message is transferred to a VoIP terminal (external line) other than the extension telephone 3 such as the IP telephone 4 via a SIP server (not shown). Then, the VoIP terminal on the outside line transmits a response message (200 OK) to the own device 1. Thereafter, the SIP processing unit 14 performs a call control procedure in accordance with SIP with the VoIP-GW apparatus 1 and the IP telephone 4 that transmitted the response message, and establishes a call with the VoIP terminal on the outside line (S10310).

  Next, the SIP processing unit 14 notifies the RTP processing unit 13 and the transmission control unit 15 of the IP address of the VoIP terminal on the outside line where the call is established with the own device 1. The outgoing call control unit 15 notifies the RTP processing unit 13 of route information indicating a line connected to the PBX 2 that is the transmission source of the SETUP message and channel information indicating the call channel specified by the SETUP message. In response to this, the RTP processing unit 13 determines the channel specified by the channel information notified from the transmission control unit 15 of the line specified by the route information notified from the transmission control unit 15 by the line IF unit 11. The RTP packet received from the PBX 2 and the RTP packet received from the VoIP terminal of the external line having the IP address notified from the SIP processing unit 14 by the IP network IF unit 12 is processed in accordance with RTP ( S10311). Thereby, a telephone call becomes possible.

  FIG. 8 is a flowchart for explaining the incoming call control process S104 of FIG.

  First, the IP network IF unit 12 notifies the SIP processing unit 14 of an INVITE message. In response to this, the SIP processing unit 14 transmits a response message (200 OK) to the source address of the INVITE message via the IP network IF unit 12. Thereafter, the SIP processing unit 14 performs a call control procedure in accordance with SIP with the call partner that has transmitted the INVITE message, establishes a call channel with the call partner, and sets the IP address of the call partner. The RTP processing unit 13 and the incoming call control unit 16 are notified (S10401). As a result, the RTP processing unit 13 receives the RTP packet addressed to the own apparatus 1 having the caller's IP address as the transmission source address via the IP network IF unit 12, and the call signal stored in the RTP packet. To restore. Also, an RTP packet destined for the IP address of the other party is generated and transmitted to the VoIP network 5 via the IP network IF unit 12.

  Next, the incoming call control unit 16 notifies the PB detection unit 18 of the IP address of the other party and instructs the detection of the PB signal sent from the other party. In response to this, the PB detection unit 18 tries to detect the PB signal from the call signal of the other party of the call received via the IP network IF unit 12 and the RTP processing unit 13. If a PB signal can be detected (YES in S10402), the process proceeds to S10405. On the other hand, if the PB signal cannot be detected after a predetermined time has elapsed (NO in S10402, YES in S10403), the PB detection unit 18 generates a voice guidance signal that prompts the user to input the called number, and this voice guidance signal Is sent to the RTP processing unit 13 together with the IP address of the other party. In response to this, the RTP processing unit 13 generates an RTP packet storing the voice guidance signal, and sends the RTP packet from the IP network IF unit 12 to the VoIP network with the IP address added to the voice guidance signal as a destination. 5 (S10404). And it tries to detect the PB signal again from the call signal of the other party.

  In the present embodiment, when the PB signal cannot be detected even after a predetermined time has elapsed, the voice partner is transmitted to prompt the input of the called number. In this case, the other party is not the VoIP-GW apparatus 1 This is because there is a high possibility that the terminal is an VoIP terminal (external line).

  In step S10405, the PB detection unit 18 specifies dial information represented by the PB signal detected from the call signal of the other party, and notifies the incoming call control unit 16 of the dial information. In response to this, the incoming call control unit 16 searches the incoming dial information TL 161 for the record 1610 in which the dial information is registered in the field 1611. Then, according to the field 1612 of the retrieved record 1610, a route (line) for receiving a call is selected (S10406). For example, in FIG. 4, in the case of dial information “5602”, a line connected to the PBX 2 with the station number “56” is selected as a route for receiving a call.

  Next, the incoming call control unit 16 edits the dial information notified from the PB detection unit 18 in accordance with the number editing conditions indicated in the fields 1613 and 1614 of the record 1610 searched in S10406, and specifies the edited result as an extension number. (S10407). For example, in FIG. 4, in the case of dial information “5602”, the upper two digits “56” of the dial information are deleted according to the deleted digits in the field 1613. Then, according to the additional number in the field 1614, the additional number “30” is added to the head of the dial information “02” from which the upper two digits are deleted. The edited number “3001” is set as the extension number.

  Next, the incoming call control unit 16 generates a SETUP message in which the extension number specified in S10407 is the called number and any free channel is the call channel, and this SETUP message is transmitted via the line IF unit 11 in S10406. The data is sent to the selected route (line) (S10408). Thereafter, if the incoming call control unit 16 receives a response to the SETUP message from the PBX 2 connected to the route selected in S10406 via the line IF unit 11 (YES in S10409), it is selected in S10406. The RTP processing unit 13 is notified of the route information of the route and the channel information indicating the call channel specified by the SETUP message. In response to this, the RTP processing unit 13 receives the channel specified by the channel information notified from the incoming call control unit 16 of the line specified by the route information notified from the incoming call control unit 16 by the line IF unit 11. The RTP packets received from the VoIP terminal having the IP address notified from the SIP processing unit 14 and the call signal received from the PBX 2 via the IP network IF unit 12 are processed in accordance with RTP (S10410). ). Thereby, a telephone call becomes possible.

  Next, in the IP extension telephone system shown in FIG. 1, the general operation will be described by taking as an example the case where the extension telephone 3 with the extension number “2001” calls the extension telephone 3 with the extension number “4002”.

  FIG. 9 is a diagram for explaining a schematic operation when the extension telephone 3 with the extension number “2001” calls the extension telephone 3 with the extension number “4002” in the IP extension telephone system shown in FIG.

  When the user of the extension telephone 3 with the extension number “2001” goes off-hook and dials “5702” (T901), the PBX 2 with the station number “55” connects the SETUP message with the designation of the called number “5702” to the own PBX 2. To the VoIP-GW apparatus 1 (IP telephone number “050-123-4567”) to be transmitted (T902).

  The VoIP-GW apparatus 1 having the IP telephone number “050-123-4567” identifies the station number “57” from the called party number “5702” sent from the PBX 2 and uses the dialing dial information TL151 to call the station number “ The VoIP-GW apparatus 1 (IP telephone number “050-234-5678”) accommodating the PBX 2 of “57” is specified (T903). Then, an INVITE message having the called number as the IP telephone number “050-234-5678” of the specified VoIP-GW apparatus 1 is transmitted (T904). This INVITE message reaches the VoIP-GW apparatus 1 having the IP telephone number “050-234-5678” via the VoIP network 5.

  Upon receiving the INVITE message, the VoIP-GW apparatus 1 having the IP telephone number “050-234-5678” receives the 200 OK message and the VoIP-GW apparatus having the IP telephone number “050-1245567” that is the transmission source of the INVITE message. 1 (T905). As a result, a call channel is established between the VoIP-GW apparatus 1 having the IP telephone number “050-1245567” and the VoIP-GW apparatus 1 having the IP telephone number “050-234-5678” (T906). .

  Next, the VoIP-GW apparatus 1 with the IP telephone number “050-1245567” is transferred from the PBX 2 to the call channel established with the VoIP-GW apparatus 1 with the IP telephone number “050-234-5678”. A PB signal representing the called number “5702” specified in the received SETUP message is transmitted (T907). Also, an ACK message corresponding to the SETUP message is transmitted to the PBX 2 with the station number “55” (T908). In response to this ACK message, the PBX 2 with the station number “55” establishes a call channel between the extension telephone 3 with the extension number “2001” and the VoIP-GW apparatus 1 with the IP telephone number “050-123-4567”. (T909).

  On the other hand, the VoIP-GW apparatus 1 with the IP telephone number “050-234-5678” is connected to the PB via the call channel established with the VoIP-GW apparatus 1 with the IP telephone number “050-234-5678”. When the signal is received, the dial information “5702” indicated by the PB signal is specified. Then, using the incoming dial information TL161, the route (station number) “57” and the extension number “4002” are specified from the dial information “5702” (T910). Then, a line connected to the PBX 2 of the specified route (station number) “57” is selected, and a SETUP message having the specified extension number “4002” as the called number is transmitted to the line (T911). The SETUP message reaches the PBX 2 with the station number “57”, and the extension telephone 3 with the extension number “4002” is called by the PBX 2.

  Next, when the user of the extension telephone 3 with the extension number “4002” responds to the call and goes off-hook, the PBX 2 with the station number “57” sends an ACK message for the SETUP message to the IP telephone number “050-234-5678”. Is transmitted to the VoIP-GW apparatus 1 (T912). As a result, a call channel is established between the extension telephone 3 with the extension number “4002” and the VoIP-GW apparatus 1 with the IP telephone number “050-234-5678” (T913). As a result, the communication channel between the extension telephone 3 with the extension number “2001” and the VoIP-GW apparatus 1 with the IP telephone number “050-123-4567”, the VoIP-GW with the IP telephone number “050-123-4567”. The communication channel between the apparatus 1 and the VoIP-GW apparatus 1 having the IP telephone number “050-234-5678”, and the VoIP-GW apparatus 1 having the IP telephone number “050-234-5678” and the extension number “4002” The call channel between the extension telephone 3 and the extension telephone 3 of the extension number “2001” and the extension telephone 3 of the extension number “4002” can be communicated (T914).

  FIG. 10 shows a schematic operation when the IP telephone 4 (external line) with the IP telephone number “050-345-6789” calls the extension telephone 3 with the extension number “4002” in the IP extension telephone system shown in FIG. It is a figure for demonstrating.

  When the user of the IP telephone 4 having the IP telephone number “050-345-6789” goes off-hook and dials “050-234-5678” (T951), the IP telephone 4 receives the call number “050-234-5678”. The INVITE message is sent to the VoIP network 5 (T952). This INVITE message reaches the VoIP-GW apparatus 1 having the IP telephone number “050-234-5678” via the VoIP network 5.

  Upon receiving the INVITE message, the VoIP-GW apparatus 1 with the IP telephone number “050-234-5678” receives a 200 OK (183 Progress) message from the IP telephone number “050-345-6789” that is the transmission source of the INVITE message. Transmit to the IP telephone 4 (T953). As a result, a communication channel is established between the IP telephone 4 having the IP telephone number “050-345-6789” and the VoIP-GW apparatus 1 having the IP telephone number “050-234-5678” (T954).

  Next, the VoIP-GW apparatus 1 with the IP telephone number “050-234-5678” has established a call channel with the IP telephone 4 with the IP telephone number “050-345-6789”, and a predetermined time has elapsed. However, if it is confirmed that no PB signal is sent from the IP telephone 4, voice guidance prompting the input of dial information is transmitted to the call channel (T 955).

  Next, when the user of the IP telephone 4 having the IP telephone number “050-345-6789” dials the dial information “5702” in accordance with the voice guidance (T956), the IP telephone 4 is informed of the IP telephone number “050-234-5678”. The PB signal representing the dial information “5702” is transmitted to the call channel established with the VoIP-GW apparatus 1 (T957).

  When the VoIP-GW apparatus 1 having the IP telephone number “050-234-5678” receives the PB signal via the call channel established with the IP telephone 4 having the IP telephone number “050-345-6789”. The dial information “5702” indicated by the PB signal is specified. Then, using the incoming dial information TL161, the route (station number) “57” and the extension number “4002” are specified from the dial information “5702” (T958). Then, a line connected to the PBX 2 of the specified route (station number) “57” is selected, and a SETUP message having the specified extension number “4002” as the called number is transmitted to the line (T959). This SETUP message reaches the PBX 2 with the station number “57”, and the extension telephone 3 with the extension number “4002” is called by the PBX 2.

  Next, when the user of the extension telephone 3 with the extension number “4002” responds to the call and goes off-hook, the PBX 2 with the station number “57” sends an ACK message for the SETUP message to the IP telephone number “050-234-5678”. Is transmitted to the VoIP-GW apparatus 1 (T960). As a result, a call channel is established between the extension telephone 3 with the extension number “4002” and the VoIP-GW apparatus 1 with the IP telephone number “050-234-5678” (T961). As a result, the communication channel between the IP telephone 4 with the IP telephone number “050-345-6789” and the VoIP-GW apparatus 1 with the IP telephone number “050-234-5678” and the IP telephone number “050-234” -5678 "VoIP-GW device 1 and the extension channel" 4002 "extension channel 3 are connected, the IP phone number" 050-345-6789 "IP phone 4 and extension number" 4002 " A telephone call between the extension telephones 3 becomes possible (T962).

  The embodiment of the present invention has been described above.

  In this embodiment, the VoIP-GW apparatus 1 makes a primary response to an incoming call, receives dial information from the other party, identifies a route (line) and extension number from the dial information, and identifies the identified route. A SETUP message with the extension number as the called number is transmitted. Therefore, according to the present embodiment, the PBX 2 can be connected to the VoIP network 5 without changing the numbering plan set for the PBX 2. In addition, incoming calls to a plurality of extension telephones 4 accommodated by the PBX 2 can be distributed using one IP telephone number.

  In addition, this invention is not limited to said embodiment, Many deformation | transformation are possible within the range of the summary. For example, in the above embodiment, the VoIP-GW apparatus 1 edits the number of dial information received from the other party and identifies the extension number. However, the present invention is not limited to this. For example, when only one PBX 2 is connected to the VoIP-GW apparatus 1 (when there is no need for route division), the dialing information of the extension number of the extension telephone 3 is directly received from the calling party, thereby omitting the number editing. You may do it.

  Moreover, in said embodiment, dial information is acquired from the other party by a PB signal. However, the present invention is not limited to this. For example, the call partner may store dial information in a SIP INFO message and transmit the dial information, and the VoIP-GW apparatus 1 may receive the dial information to obtain the dial information from the call partner.

  In the above embodiment, the case where SIP is used as the call control protocol used for the IP telephone service based on VoIP has been described as an example. However, the present invention is not limited to this. For example, H.323 may be used.

  Moreover, each structure of the VoIP gateway apparatus 1 mentioned above may not be implement | achieved when a computer runs a program. It may be executed in hardware by an integrated logic IC such as ASIC (Application Specific Integrated Circuit) or FPGA (Field Programmable Gate Array), or may be executed in software by a computer such as DSP (Digital Signal Processor). It may be a thing.

FIG. 1 is a schematic diagram of an IP extension telephone system according to an embodiment of the present invention. FIG. 2 is a schematic diagram of the VoIP-GW apparatus 1 shown in FIG. FIG. 3 is a diagram schematically showing the dialing information for outgoing call TL151. FIG. 4 is a diagram schematically showing incoming dial information TL161. FIG. 5 is a diagram illustrating a hardware configuration example of the VoIP-GW apparatus 1. FIG. 6 is a flowchart for explaining the schematic operation of the VoIP-GW apparatus 1. FIG. 7 is a flowchart for explaining the transmission control process S103 of FIG. FIG. 8 is a flowchart for explaining the incoming call control process S104 of FIG. FIG. 9 is a diagram for explaining a schematic operation when the extension telephone 3 with the extension number “2001” calls the extension telephone 3 with the extension number “4002” in the IP extension telephone system shown in FIG. FIG. 10 illustrates the schematic operation when the IP telephone 4 (external line) with the IP telephone number “050-345-6789” calls the extension telephone 3 with the extension number “4002” in the IP extension telephone system shown in FIG. It is a figure for doing.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... VoIP-GW apparatus, 2 ... PBX, 3 ... Extension telephone, 4 ... IP telephone, 5 ... VoIP network, 11 ... Line IF part, 12 ... IP network IF part, 13 ... RTP processing part, 14 ... SIP processing part , 15 ... outgoing call control unit, 16 ... incoming call control unit, 17 ... PB sending unit, 18 ... PB detection unit, 151 ... outgoing dial information TL, 161 ... incoming dial information TL

Claims (2)

A VoIP gateway device that relays a call between a telephone line interface accommodating a plurality of telephone lines and a VoIP network interface connected to the VoIP network,
Incoming dial information storage means for storing route information indicating a telephone line for receiving a call for each dial information and number editing information for generating an extension number from the dial information;
And dialing information detecting means for detect the dialing information in response when receiving an incoming call from said VoIP network via the VoIP network interface
An incoming call that causes a call to be received via the telephone line interface to the telephone line indicated by the route information stored in the incoming dial information storage means in association with the dial information detected by the dial information detecting means. Control means;
A telephone line that generates an extension number in accordance with the number editing information stored in the incoming dial information storage means in association with the dial information detected by the dial information detection means, and the incoming call control means receives the call. And an extension number transmitting means for transmitting the extension number via the telephone line interface . A VoIP gateway device that relays a call between a telephone line interface accommodating a plurality of telephone lines and a VoIP network interface connected to the VoIP network,
For each dial information, incoming dial information storage means storing route information indicating a telephone line for receiving a call;
And dialing information detecting means for detect the dialing information in response when receiving an incoming call from the VoIP network via said VoIP network interface,
An incoming call that causes a call to be received via the telephone line interface to the telephone line indicated by the route information stored in the incoming dial information storage means in association with the dial information detected by the dial information detecting means. possess and control means, the,
The dial information detecting means includes
A VoIP gateway device characterized in that , if dial information is not detected within a predetermined time after the primary response, voice guidance for prompting input of the dial information is sent to the communication path established by the response .

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