JP2008205874A - Gateway device and call relay method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide technique capable of surely notifying a user that a public telephone service is used in the case of performing detour transmission to a public telephone network in a gateway for making transmission to an IP telephone network and performing detour transmission to the public telephone network during a failure of the IP telephone network. <P>SOLUTION: The gateway 1 makes transmission to the IP telephone network 5 and performs detour transmission to the public telephone network 7 during a failure of the IP telephone network 5. In the case of performing detour transmission to the public telephone network 7 here, a speech communication path is established with an accommodation terminal 3 being a call transmission source before the detour transmission, and voice guidance to the effect that the public telephone service is used is transmitted to the speech communication path. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a gateway device that relays a call between a telephone line and an IP telephone network, and more particularly to a gateway device that makes a detour call to a public telephone network when an IP telephone network fails.

  There is known a gateway device that relays a call between a telephone line and an IP telephone network (VoIP network). The gateway device described in Patent Document 1 relays an incoming call via a telephone line to an IP telephone network, and provides an IP telephone service to an existing PBX or telephone connected to the telephone line. Here, when a failure occurs in the IP telephone network, a call received via the telephone line is relayed to the public telephone network by detouring to the public telephone network (PSTN), and the telephone line is connected to the telephone line. Providing public telephone service to an existing connected PBX or telephone.

JP 2001-333114 A

  The charging system is often different between the IP telephone service and the public telephone service. In general, public telephone services often have higher call charges than IP telephone services. For this reason, when using the public telephone service, it is preferable to notify the existing PBX or telephone connected to the telephone line to that effect. However, the technique described in Patent Document 1 does not consider this point at all.

  A method of notifying the use of the public telephone service by sending a special tone signal to an existing PBX or telephone connected to the telephone line is also conceivable. However, with this method, a user who does not know the meaning of a special tone signal cannot understand that it is a signal to start using a public telephone service.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to make a detour to the public telephone network in a gateway device that transmits to the IP telephone network and makes a detour to the public telephone network when the IP telephone network fails. An object of the present invention is to provide a technology capable of surely informing a user that a public telephone service is used when making a call.

  In order to solve the above problems, in the present invention, when making a detour call to the public telephone network, prior to this detour call, a call path is established with the accommodating terminal that is the call originator, and this call path Voice guidance to use public telephone service is sent to.

For example, the present invention is a gateway device for relaying a call,
A telephone line interface accommodating at least one telephone line;
An IP telephone network interface connected to the IP telephone network;
A public telephone network interface connected to the public telephone network;
A call received from the telephone line via the telephone line interface is relayed to the IP telephone network via the IP telephone network interface, and a response of the IP telephone network to the call matches a predetermined detour condition. A control means for relaying the call to the public telephone network via the public telephone network interface,
The control means includes
When a call is relayed to the public telephone network via the public telephone network interface, a call path is established with the call originator via the telephone line interface prior to the relay, and the call Send voice guidance to the road.

Here, the control means includes
When a switching instruction from the call source to the public telephone network is accepted via the telephone line interface, the call may be relayed to the public telephone network.

  According to the present invention, prior to the detour call to the public telephone network, a call path is established with the call originator, and voice guidance to the effect that the public telephone service is used is sent to the call path. The user can be surely notified that the public telephone service is used.

  Embodiments of the present invention will be described below.

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

  As shown in the figure, the gateway 1 of the present embodiment accommodates accommodation terminals 3 such as analog telephones, ISDN telephones, and PBXs via telephone lines 2 such as analog telephone lines, ISDN lines, and OD lines. The gateway 1 is connected to an IP telephone network (VoIP network) 5 via a router 4. Connected to the IP telephone network 5 is an IP telephone server (SIP server) 6 for providing IP telephone services to subscribers.

  In the above configuration, the gateway 1 relays the call to the IP telephone server 6 when a call is received from the accommodating terminal 3 via the telephone line 2. Also, it is determined whether the response of the IP telephone server 6 to this call matches a predetermined detour condition. When a predetermined detour condition is met, a speech path is established with the accommodating terminal 3 that is the call originator, and voice guidance is sent to the effect that the public telephone service is used on the established speech path. To do. Thereafter, the call is detoured to the public telephone network (PSTN) 7 and a call received from the accommodating terminal 3 is relayed to the public telephone network 7.

  FIG. 2 is a schematic diagram of the gateway 1 shown in FIG.

  As shown in the figure, the gateway 1 of this embodiment includes a telephone line IF (interface) unit 11, an IP telephone network IF unit 12, a public telephone network IF unit 13, a configuration information storage unit 14, and a main control unit. 15 and.

  The telephone line IF unit 11 is an interface for connecting to a telephone line 2 such as an analog telephone line, an ISDN line, or an OD line. The telephone line IF unit 11 includes at least one of an analog telephone IF unit 111 for accommodating an analog telephone line, an ISDNIF unit 112 for accommodating an ISDN line, and an ODIF unit 113 for accommodating an OD line. It has at least one IF section. The telephone line IF unit 11 is connected to the accommodating terminal 3 such as an analog telephone, an ISDN telephone, or a PBX via the telephone line 2 accommodated in these IF units 111 to 113.

  The IP telephone network IF unit 12 is an interface for connecting to the IP telephone network 5 and has an IP processing function, a UDP processing function, an RTP processing function, and a SIP processing function.

  The public telephone network IF unit 13 is an interface for connecting to the public telephone network 7.

  The configuration information storage unit 14 stores information (configuration information) necessary for the accommodation terminal 3 to enjoy the IP telephone service and the public telephone service. The configuration information storage unit 14 includes a relay destination storage unit 141, a detour condition storage unit 142, and a number plan storage unit 143.

  The relay destination storage unit 141 stores, for each telephone line 2 accommodated by the telephone line IF unit 11, an IP telephone server 6 that can be used by the accommodating terminal 3 connected to the telephone line 2.

FIG. 3 is a diagram schematically showing the registered contents of the relay destination storage unit 141. As shown in the figure, the relay destination storage unit 141 has a record 1410 for each telephone line 2 accommodated by the telephone line IF unit 11. The record 1410 has a field 1411 for registering a telephone line ID, which is identification information of the telephone line 2, and the address of the IP telephone server 6 that can be used by the accommodating terminal 3 connected to the telephone line 2 with high priority. Fields 1412 ₁ , 1412 ₂ ,. . . And having. Here, the address of the IP telephone server 6 with the priority n is registered in the field 1412 _n . When there is no n-th priority IP telephone server 6, null data “Null” is registered in the field 1412 _n .

  The detour condition storage unit 142 stores a condition (a detour condition) for detouring the IP telephone server 6 for each IP telephone server 6 that can be used by the accommodating terminal 3.

  FIG. 4 is a diagram schematically showing the registration contents of the detour condition storage unit 142. As illustrated, the detour condition storage unit 142 includes a record 1420 for each IP telephone server 6 that can be used by the accommodating terminal 3. The record 1420 has a field 1421 for registering the address of the IP telephone server 6, and a field 1422 for registering an IP telephone server detour condition that is a detour condition when making a detour call from the IP telephone server 6 to another IP telephone server 6. And a field 1423 for registering a public telephone network detour condition, which is a detour condition when making a detour call from the IP telephone server 6 to the public telephone network 7.

  The number plan storage unit 143 stores a number plan table for each telephone line 2 accommodated by the telephone line IF unit 11.

  FIG. 5 is a diagram schematically showing the registered contents of the number plan storage unit 143. As shown in the figure, each telephone line 2 accommodated by the telephone line IF unit 11 has a numbering plan table 1430. The number plan table 1430 includes a record 1431 for each combination of a call relay destination (either the IP telephone network 5 or the public telephone network 7) and a head number of a destination telephone number (called number) to be edited. Have The record 1431 includes a field 1432 for registering a call relay destination, a field 1433 for registering the head number of the destination telephone number, a field 1434 for registering the number of digits deleted from the head number of the telephone number, and the telephone number. And a field 1435 for registering a number to be added.

  The main control unit 15 provides an IP telephone service and a public telephone service to the accommodating terminal 3 in cooperation with each unit of the gateway 1.

  Specifically, when a call arrives from the IP telephone network 5 or the public telephone network 7 via the router 4, the main control unit 15 sends this call to the accommodating terminal 3 specified by the called number of this call. Relay. As a result, a communication path is formed between the call originator and the accommodating terminal 3 specified by the call destination number (incoming call processing).

  Further, when a call arrives from the accommodation terminal 3, the main control unit 15 relays this call to the IP telephone server 6. As a result, a communication path is formed between the accommodating terminal 3 and the destination of the call via the IP telephone network 5. Here, when the response of the IP telephone server 6 matches a predetermined detour condition, a voice path is established with the accommodating terminal 3 and voice guidance to the effect that the public telephone service is used is established on the established telephone path. Send it out. Thereafter, the call is detoured to the public telephone network 7, and the call received from the accommodation terminal 3 is relayed to the public telephone network 7. As a result, a communication path is formed between the accommodating terminal 3 and the destination of the call via the public telephone network 7 (transmission processing).

  FIG. 6 is a flowchart for explaining the operation of the gateway 1 shown in FIG.

  When a call (INVITE message) arrives from the IP telephone network 5 via the router 4 (YES in S11), the IP telephone network IF unit 12 notifies the main control unit 15 of this call. In response to this, the main control unit 15 performs incoming processing. That is, the main control unit 15 specifies the telephone line 2 corresponding to the called number of the call with reference to station data not shown. A call received from the IP telephone network 5 is transferred to the identified telephone line 2 via the telephone line IF unit 11. Thereafter, data transmission / reception between the telephone line 2 and the IP telephone network 5 is relayed. As a result, a call path is formed via the IP telephone network 5 between the call originator and the accommodating terminal 3 connected to the telephone line 2 (S12).

  In addition, when a call arrives from the public telephone network 7 (YES in S13), the public telephone network IF unit 13 notifies the main control unit 15 of this call. In response to this, the main control unit 15 performs incoming processing. That is, the main control unit 15 specifies the telephone line 2 corresponding to the called number of the call with reference to station data not shown. A call received from the public telephone network 7 is transferred to the identified telephone line 2 via the telephone line IF unit 11. Thereafter, data transmission / reception between the telephone line 2 and the public telephone network 7 is relayed. Thus, a communication path is formed via the public telephone network 7 between the call originator and the accommodating terminal 3 connected to the telephone line 2 (S14).

  Further, when a call is received from the accommodated telephone line 2 (YES in S15), the telephone line network IF unit 11 notifies the main control unit 15 of this call. In response to this, the main control unit 15 performs a transmission process described later (S16).

  FIG. 7 is a flowchart for explaining the details of the calling process (S16) shown in FIG.

First, the main control unit 15 sets a counter value n to 1 (S1601). Next, the main control unit 15 retrieves the record 1410 from the relay destination storage unit 141 of the configuration information storage unit 141 using the telephone line ID assigned to the telephone line 2 of the call originator as a key, and the retrieved record It is checked whether or not the address of the IP telephone server 6 with the priority n is registered in the field 1412 _n of 1410 (S1602). If registered (YES in S1602), the process proceeds to S1603. On the other hand, if not registered (NO in S1602), the process proceeds to S1609.

  In step S1603, the main control unit 15 searches the number plan storage unit 143 from the number plan table 1430 using the telephone line ID assigned to the telephone line 2 of the call originator as a key. Then, from the retrieved numbering plan table 1430, the record 1431 in which the IP telephone network 5 is registered as the call relay destination in the field 1432 and the first number of the called party number (the destination telephone number) is registered in the field 1433. Search for more. If such a record 1431 can be searched, the called number is edited according to the numbering plan registered in this record 1431. Specifically, the number of deleted digits registered in the field 1434 is deleted from the called number, and an additional number registered in the field 14344 is added to the called number.

  Next, the main control unit 15 controls the IP telephone network IF unit 12 and transfers the call with the called number edited to the IP telephone server 6 with the priority n (S1604).

  When the main control unit 15 transfers the call to the IP telephone server 6 with the priority n and receives a response to the call, the main control unit 15 records from the detour condition storage unit 142 using the address of the IP telephone server 6 as a key. 1420 is searched. Then, it is determined whether or not the response to the call of the IP telephone server 6 matches the IP telephone server detour condition registered in the field 1422 of the record 1420 (S1605). For example, when the address of the IP telephone server 6 with the priority n is “192.168.10.1”, in the example shown in FIG. 4, the response from the IP telephone server 6 is “408 response” or “486 response”. If so, it is determined that the IP telephone server bypass condition is met.

  If it is determined that the IP telephone server bypass condition is met (YES in S1605), the main control unit 15 increments the counter value by one (S1606), and then returns to S1602. On the other hand, if it is determined that the IP telephone server bypass condition is not met (NO in S1605), the process proceeds to S1607.

  In S1607, the main control unit 15 determines whether or not the response to the call of the IP telephone server 6 having the priority n matches the public telephone network detour condition registered in the field 1423 of the record 1420 searched in S1605. to decide. For example, when the address of the IP telephone server 6 with priority n is “192.168.10.1”, in the example shown in FIG. 4, the responses from the IP telephone server 6 are “408 response”, “486 response”. And “no response (timeout)”, it is determined that the public telephone network detour condition is met.

  If it is determined that the public telephone network detour condition is met (YES in S1607), the process proceeds to S1609. On the other hand, if it is determined that the public telephone network detour condition is not met (NO in S1607), the main control unit 15 transmits / receives the call between the telephone line 2 of the call originator and the IP telephone server 6 of priority n. The data to be relayed is relayed (S1608). As a result, a communication path is established between the accommodating terminal 3 that is the call source and the call partner that is the destination of the call via the IP telephone network 5.

  In step S <b> 1609, the main control unit 15 controls the telephone line IF unit 11 to establish a communication path with the accommodating terminal 3 that is a call source. Then, voice guidance for confirming that the public telephone network is used is sent to the accommodation terminal 3 via this communication path (S1610). And it waits for the detour instruction | indication which shows the presence or absence of use of a public telephone network by the PB signal from the accommodation terminal 3 via this communication path, for example (S1611).

  If the detour instruction received from the accommodation terminal 3 indicates that the public telephone network is not used (NG in S1611), this flow ends. On the other hand, if it indicates that the public telephone network is to be used (S1611: OK), the process proceeds to S1612.

  In step S <b> 1612, the main control unit 15 searches the number plan storage unit 143 from the number plan table 1430 using the telephone line ID assigned to the telephone line 2 as the call originator as a key. Then, from the retrieved numbering plan table 1430, the record 1431 in which the public telephone network 7 is registered as a call relay destination in the field 1432 and the first number of the called party number (destination telephone number) is registered in the field 1433. Search for more. If such a record 1431 can be searched, the called number is edited according to the numbering plan registered in this record 1431. Specifically, the number of deleted digits registered in the field 1434 is deleted from the called number, and an additional number registered in the field 1435 is added to the called number.

  Next, the main control unit 15 controls the public telephone network IF unit 13 to transfer the call with the called number edited to the public telephone network 7 (S1613). Then, the main control unit 15 receives a connection response from the public telephone network 7 via the public telephone network IF unit 13, and thereby, via the public telephone network 7, between the call partner as a call destination. It waits for a call path to be established (S1614). Thereafter, the main control unit 15 relays this call path and the call path established in advance between the accommodating terminal 3 that is the call originator in S1609 (S1615). As a result, a communication path is established between the accommodating terminal 3 that is the call source and the call partner that is the destination of the call via the public telephone network 7.

  Next, an example of a call control procedure in the IP telephone system shown in FIG. 1 will be described.

  FIG. 8 is a sequence diagram for explaining an example of a call control procedure when the accommodating terminal 3 connected to the telephone line 2 having the telephone line ID “01” in FIG. 3 makes a call.

  When a call arrives from the accommodation terminal 3 (S201), the gateway 1 determines the relay destination of this call and edits the number of the called number as necessary (S202).

That is, the gateway 1 retrieves the record 1410 from the relay destination storage unit 141 of the configuration information storage unit 141 using the telephone line ID “01” of the telephone line 2 to which the accommodating terminal 3 is connected as a key. Then, the IP telephone server 6 (address “192.168.21.1”) with the priority “1” registered in the field 1412 _{1 of the} record 1410 is determined as the call relay destination. In addition, the telephone line ID “01” of the telephone line 2 to which the accommodating terminal 3 is connected is used as a key to search the numbering plan table 1430 from the numbering plan storage unit 143, and the relay destination “IP telephone network” and the call The record 1431 is further searched from the searched numbering plan table 143 using the first number of the called number as a key. If the record 1431 can be searched, the call arrival number is edited according to the numbering plan registered in the record 1431.

  Next, the gateway 1 sends an IP phone server 6 (address “192.168.21.1”) determined as the relay destination to the INVITE message representing the call whose called number is edited as necessary. (S203).

  When the gateway 1 receives a 486 response from the IP telephone server 6 (address “192.168.21.1”) (S204), the bypass condition storage shown in FIG. 4 is stored using the address of the IP telephone server 6 as a key. The record 1420 is searched from the unit 142, and it is confirmed whether or not the 486 response is included in the IP telephone server bypass condition of the record 1420. When it is confirmed that the 486 response is included in the IP telephone server bypass condition, a new relay destination of this call is determined, and the number of the called number is edited as necessary (S205).

That, IP telephone server 6 (address "192.168.10.1") priority that is registered retrieved field 1412 the _second record 1410 of the relay destination storage unit 141 in step S202, "2" new a call Determine the relay destination. Further, the record 1431 is retrieved from the number plan table 1430 retrieved in S202, using the relay destination “IP telephone network” and the first number of the called party number as keys. If the record 1431 can be searched, the call arrival number is edited according to the numbering plan registered in the record 1431.

  Next, the gateway 1 sends the INVITE message representing the call whose called number is edited as necessary as described above to the IP telephone server 6 (address “192.168.10.1” determined as the new relay destination). ]) (S206).

  When the gateway 1 receives a 408 response from the IP telephone server 6 (address “192.168.10.1”) (S207), the bypass condition storage shown in FIG. 4 is stored using the address of the IP telephone server 6 as a key. The record 1420 is searched from the unit 142, and it is confirmed whether or not the 408 response is included in the IP telephone server bypass condition of the record 1420. When it is confirmed that the 408 response is included in the IP telephone server bypass condition, a new relay destination of this call is determined (S208).

That is, to verify that the IP telephone server 6 priority "3" in the field 1412 _third record 1410 of the relay destination storage unit 141 searched in S202 is not registered, a new relay destination of the call to the public telephone network 7 To decide.

  Next, the gateway 1 establishes a communication path with the accommodating terminal 3 that is a call source, and confirms that the public telephone network 7 is used for the accommodating terminal 3 through the communication path. Is sent (S209). When the gateway 1 receives a detour instruction indicating that the use of the public telephone network 7 is permitted from the accommodating terminal 3 via this communication path (S210), the gateway 1 performs number editing of the called number as necessary (S210). S211).

  That is, the record 1431 is retrieved from the number plan table 1430 retrieved in S202, using the relay destination “public telephone network” and the first number of the called party number as keys. If the record 1431 can be searched, the call arrival number is edited according to the numbering plan registered in the record 1431.

  Then, the gateway 1 transmits the call with the called number edited as necessary to the public telephone network 7 as described above (S212).

  FIG. 9 is a sequence diagram for explaining an example of a call control procedure when the accommodating terminal 3 connected to the telephone line 2 having the telephone line ID “02” in FIG. 3 makes a call.

  When a call arrives from the accommodation terminal 3 (S221), the gateway 1 determines a relay destination of this call (S222).

That is, the gateway 1 retrieves the record 1410 from the relay destination storage unit 141 of the configuration information storage unit 141 using the telephone line ID “02” of the telephone line 2 to which the accommodating terminal 3 is connected as a key. Then, IP telephone server 6 of the priority "1" in the field 1412 ₁ of this record 1410 is to make sure that is not registered, to determine the public telephone network 7 to the relay destination of the call.

  Next, the gateway 1 establishes a communication path with the accommodating terminal 3 that is a call source, and confirms that the public telephone network 7 is used for the accommodating terminal 3 through the communication path. The voice guidance is sent out (S223). When the gateway 1 receives a detour instruction indicating that the use of the public telephone network 7 is permitted from the accommodation terminal 3 through the communication path (S224), the gateway 1 performs number editing of the called number as necessary (S224). S225).

  That is, using the telephone line ID “02” of the telephone line 2 to which the accommodating terminal 3 is connected as a key, the numbering plan table 1430 is searched from the numbering plan storage unit 143 and the relay destination “public telephone network” and the call The record 1431 is further searched from the searched numbering plan table 1430 using the first number of the called number as a key. If the record 1431 can be searched, the call arrival number is edited according to the numbering plan registered in the record 1431.

  Then, the gateway 1 transmits the call with the called number edited as necessary to the public telephone network 7 as described above (S226).

  FIG. 10 is a sequence diagram for explaining an example of a call control procedure when the accommodating terminal 3 connected to the telephone line 2 having the telephone line ID “03” in FIG. 3 places a call.

  When a call arrives from the accommodation terminal 3 (S231), the gateway 1 determines the relay destination of this call and edits the number of the called number as necessary (S232).

That is, the gateway 1 searches the record 1410 from the relay destination storage unit 141 of the configuration information storage unit 141 using the telephone line ID “03” of the telephone line 2 to which the accommodating terminal 3 is connected as a key. Then, to determine the IP telephone server 6 of the priority "1" registered in the field 1412 ₁ of the record 1410 (the address "192.168.10.1") to the relay destination of the call. In addition, the telephone line ID “03” of the telephone line 2 to which the accommodating terminal 3 is connected is used as a key to search the numbering plan table 1430 from the numbering plan storage unit 143, and the relay destination “IP telephone network” and the call The record 1431 is further searched from the searched numbering plan table 1430 using the first number of the called number as a key. If the record 1431 can be searched, the call arrival number is edited according to the numbering plan registered in the record 1431.

  Next, the gateway 1 sends an IP phone server 6 (address “192.168.10.1”) determined as the relay destination to the INVITE message representing the call whose called number is edited as necessary. (S233).

  Here, it is assumed that a failure has occurred in the IP telephone network 5, and therefore the INVITE message has not arrived at the relay destination IP telephone server 6 (address “192.168.10.1”). In this case, the IP telephone server 6 (address “192.168.10.1”) does not return a response to the gateway 1.

  When the gateway 1 detects that the response of the IP telephone server 6 (address “192.168.10.1”) has timed out (S234), the gateway 1 uses the address of the IP telephone server 6 as a key, as shown in FIG. The record 1420 is searched from the detour condition storage unit 142, and it is confirmed whether or not the response timeout is included in the IP telephone server detour condition of the record 1420. Then, when it is confirmed that it is not registered, it is further confirmed whether or not a response timeout is included in the public telephone network bypass condition 1423 of this record 1420. After confirming that the response timeout is included in the public telephone network bypass condition 1423, the gateway 1 determines the public line network 7 as a new relay destination (S235).

  Next, the gateway 1 establishes a communication path with the accommodating terminal 3 that is a call source, and confirms that the public telephone network 7 is used for the accommodating terminal 3 through the communication path. The voice guidance is sent out (S236). When the gateway 1 receives a detour instruction indicating that the use of the public telephone network 7 is permitted from the accommodation terminal 3 through the communication path (S237), the gateway 1 edits the number of the called number as necessary (S237). S238).

  That is, the record 1431 is retrieved from the number plan table 1430 retrieved in S232, using the relay destination “public telephone network” and the first number of the called party number as keys. If the record 1431 can be searched, the call arrival number is edited according to the numbering plan registered in the record 1431.

  Then, the gateway 1 transmits the call with the called number edited as necessary to the public telephone network 7 as described above (S239).

  The embodiment of the present invention has been described above.

  In the present embodiment, prior to the detour transmission to the public telephone network 7, a communication path is established with the call originator, and voice guidance to the effect that the public telephone service is used is transmitted to this communication path. Therefore, according to the present embodiment, it is possible to reliably notify the user of the accommodation terminal 3 that the public telephone service is used.

  In the present embodiment, the public telephone service is provided to the accommodation terminal 3 only when a detour instruction for permitting the use of the public telephone service is received from the user of the accommodation terminal 3. For this reason, a user who does not wish to use the public telephone service can refuse to use the public telephone service.

  In the present embodiment, if the response of the IP telephone server 6 corresponds to the IP telephone server bypass condition, there is another IP telephone server 6 associated with the telephone line 2 that is the call source. The call is relayed to the other IP telephone server 6, and the call is relayed to the public telephone network 7 only when there is not. Therefore, according to the present embodiment, the IP telephone service can be preferentially provided to the user of the accommodation terminal 3.

  Further, in this embodiment, when the response of the IP telephone server 6 corresponds only to the public telephone network detour condition, even when there is another IP telephone server 6 associated with the telephone line 2 that is the call originator. The call is relayed to the public telephone network 7. Therefore, according to the present embodiment, the public telephone service can be provided to the user of the accommodation terminal 3 more quickly.

  In addition, this invention is not limited to said embodiment, Many deformation | transformation are possible within the range of the summary. For example, the configuration of the gateway 1 may be executed by an integrated logic IC such as an Application Specific Integrated Circuit (ASIC) or a Field Programmable Gate Array (FPGA), or may be a DSP (Digital Signal Process). It may be executed by software by a computer such as a personal computer.

  For example, a CPU, a memory for storing program and configuration information, an analog telephone line, an ISDN line, an OD line, etc., and a line IF for communicating with the accommodating terminal 3 via these lines, for example, a LAN cable The network IF that communicates with the IP telephone network 6 via this cable, the public telephone line IF that communicates with the public telephone network 7 via this telephone line, and these components. May be realized by a CPU executing a program stored in a memory. In this case, the configuration information storage unit 14 has a memory, the telephone line IF unit 11 has a line IF, the IP telephone network IF unit 12 has a network IF, and the public telephone network IF unit 13 has a public telephone line IF. Is used.

  In the present embodiment, the gateway 1 may be directly connected to the IP telephone network 5 by providing the gateway 1 with the function of the router 4.

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

FIG. 1 is a schematic diagram of an IP telephone system including a gateway 1 to which an embodiment of the present invention is applied. FIG. 2 is a schematic diagram of the gateway 1 shown in FIG. FIG. 3 is a diagram schematically showing the registration contents of the relay destination storage unit 141. FIG. 4 is a diagram schematically showing the registration contents of the detour condition storage unit 142. FIG. 5 is a diagram schematically showing the registered contents of the number plan storage unit 143. FIG. 6 is a flowchart for explaining the operation of the gateway 1 shown in FIG. FIG. 7 is a flowchart for explaining the calling process (S16) shown in FIG. FIG. 8 is a sequence diagram for explaining an example of a call control procedure when the accommodating terminal 3 connected to the telephone line 2 having the telephone line ID “01” in FIG. 3 makes a call. FIG. 9 is a sequence diagram for explaining an example of a call control procedure when the accommodating terminal 3 connected to the telephone line 2 having the telephone line ID “02” in FIG. 3 makes a call. FIG. 10 is a sequence diagram for explaining an example of a call control procedure when the accommodating terminal 3 connected to the telephone line 2 having the telephone line ID “03” in FIG. 3 places a call.

Explanation of symbols

  1: gateway, 2: telephone line, 3: accommodating terminal, 4: router, 5: IP telephone network, 6: IP telephone server, 7: public line network, 11: telephone line IF section, 12: IP telephone network IF section , 13: Public telephone network IF unit, 14: Configuration information storage unit, 15: Main control unit, 111: Analog telephone IF unit, 112: ISDNIF unit, 113: ODIF unit, 141: Relay destination storage unit, 142: Detour condition Storage unit, 143: Number plan storage unit

Claims (7)

A gateway device that relays calls,
A telephone line interface accommodating at least one telephone line;
An IP telephone network interface connected to the IP telephone network;
A public telephone network interface connected to the public telephone network;
A call received from the telephone line via the telephone line interface is relayed to the IP telephone network via the IP telephone network interface, and a response of the IP telephone network to the call matches a predetermined detour condition. A control means for relaying the call to the public telephone network via the public telephone network interface,
The control means includes
When a call is relayed to the public telephone network via the public telephone network interface, a call path is established with the call originator via the telephone line interface prior to the relay, and the call A gateway device characterized by sending voice guidance to a road. The gateway device according to claim 1,
The control means includes
A gateway device that relays a call to the public telephone network when an instruction to switch from the call source to the public telephone network is received via the telephone line interface. The gateway device according to claim 1 or 2,
Server registration means for registering an IP telephone server that can be used by a terminal connected to the telephone line for each telephone line;
The control means includes
Relaying a call received from the telephone line via the telephone line interface to an IP telephone server registered in the server registration means in association with the telephone line via the IP telephone network interface. A gateway device characterized. The gateway device according to claim 3,
The predetermined detour condition is
Including failure notification from the IP phone server,
The control means includes
When the failure notification is received from the IP telephone server that is the call relay destination, there is another IP telephone server that is registered in the server registration means in association with the telephone line connected to the call source. A gateway device characterized in that, if there is, the call is relayed to the other IP telephone server, and if not, the call is relayed to the public telephone network. The gateway device according to claim 4,
The predetermined detour condition is
Including timeout of response from IP phone server,
The control means includes
When a response from the IP telephone server which is a call relay destination times out, there is another IP telephone server registered in the server registration means in association with the telephone line connected to the call originator. However, a gateway device that relays the call to the public telephone network. The gateway device according to any one of claims 1 to 5,
A numbering plan registration means for registering a numbering plan in association with the telephone line accommodated by the telephone line interface;
The control means includes
Edit the called number of a call received from the telephone line via the telephone line interface according to the number plan registered in the number plan registration means in association with the telephone line, and relay the call The gateway apparatus characterized by this. A call relay method,
When a call is received from a telephone line, the call is relayed to the IP telephone network.
Determining whether a response of the IP telephone network to the call matches a predetermined detour condition;
If the response matches the predetermined detour condition, a call path is established with the call originator, voice guidance is sent to the call path, and then the call is relayed to the public telephone network. A call relay method characterized by:

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