JP2005123730A - Alternate route control method of communication trunk, alternate route control program, and recording medium recording program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform smooth routing to another trunk alternative to an IP trunk. <P>SOLUTION: A control apparatus (20) houses a telephone set (10) and a plurality of communication trunks (30, 40, 50) including an IP trunk (60) for the telephone set. In this apparatus (20), alternate trunk information indicating the correlation between the telephone set and the alternate trunk of a predetermined communication trunk other than the IP trunk among the plurality of communication trunks, and alternate number information indicating a telephone number used for connecting to the alternate trunk, are set. The propriety of using the IP trunk is judged when the telephone set sends a transmission request to the IP trunk. An alternate trunk corresponding to the telephone set is selected on the basis of the alternate trunk information if it is judged that the IP trunk should not be used. The telephone number for the selected alternate trunk is acquired from the alternate number information. The telephone set is connected to the alternate trunk on the basis of the acquired telephone number. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention provides a control device that accommodates a plurality of communication trunks including an IP trunk for transmitting voice data according to VoIP (Voice over Internet Protocol) on an IP network and a telephone, and bypasses the communication trunk instead of the IP trunk. It is related with the method of controlling.

Conventionally, when an attempt is made to make an outgoing call using an IP trunk from a telephone, if the trunk is unusable due to communication congestion or the like, the user once terminates the call, and then reopens the PSTN (Public Switched Telephone Networks). It was necessary to perform outgoing work to other communication trunks such as In order to eliminate such troublesome work, for example, a technique as shown in Patent Document 1 described below has been proposed. In this technique, when a captured trunk circuit is unusable, it is determined whether or not trunks can be used in a preset order for a plurality of communication trunks, and usable trunks are selected accordingly.
Japanese Patent Laid-Open No. 03-250952

  However, in the above-described method, since a plurality of trunk circuits are confirmed in a predetermined order each time, it takes time to determine whether or not the trunk circuit can be used, and detouring to another trunk may be delayed. Further, when the difference in connection costs between the trunks is significant, there is a risk that it will be inconvenient for the user if it is automatically detoured to an arbitrary trunk.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a detour control method for smoothly detouring a communication trunk when making a call from a telephone.

  A detour control method according to the present invention is a method for controlling detouring of a communication trunk in a control device that accommodates a telephone and a plurality of communication trunks including an IP trunk for the telephone, Set detour trunk information indicating the correspondence between the detour trunk, which is a predetermined communication trunk other than the IP trunk, and the telephone, and detour number information indicating a telephone number for connecting to the detour trunk, When there is a call request from the telephone to the IP trunk, it is determined whether or not the IP trunk can be used, and when it is determined that the IP trunk cannot be used, a bypass trunk corresponding to the telephone is selected based on the bypass trunk information. The telephone number for the selected detour trunk is acquired from the detour number information, and the acquired telephone number is The serial telephone, characterized in that connected to the bypass trunk.

  A bypass control program according to the present invention is a program for controlling a bypass of a communication trunk in a control device that accommodates a telephone and a plurality of communication trunks including an IP trunk for the telephone. Detour trunk information indicating a correspondence relationship between the telephone and a detour trunk that is a predetermined communication trunk other than an IP trunk among the communication trunks, and detour number information indicating a telephone number for connecting to the detour trunk When the call is requested from the telephone to the IP trunk, it is determined whether or not the IP trunk can be used. When it is determined that the IP trunk is not usable, the bypass for the telephone corresponding to the telephone based on the bypass trunk information is determined. A trunk is selected, and a telephone number for the selected bypass trunk is obtained from the bypass number information. To connect the phone to the bypass trunk by the acquired telephone number, characterized in that to be executed by the control device.

  Furthermore, a recording medium according to the present invention is characterized in that the detour control program is recorded.

  According to the detour control method of the present invention, since a detour trunk is set in advance for an IP trunk, a communication trunk to be used for detour can be quickly determined even if the IP trunk becomes unusable. Can do. Thereby, a communication delay caused by bypassing the communication trunk can be prevented.

[Example 1]
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram of a system 100 to which an embodiment of a detour control method according to the present invention is applied. The system 100 includes a telephone 10 that is a button telephone having a VoIP call function, and a main apparatus 20 that is a control device that accommodates the telephone 10. The main device 20 is for connecting the public network such as the PSTN network 30 as an analog network and the ISDN (Integrated Services Digital Network) network 40 as a digital network, the private network 50, and the telephone 10 by extension. The LAN 60 is accommodated. The LAN 60 includes an IP trunk that is a communication line that connects voice communication of the telephone 10 in accordance with the Internet protocol (hereinafter simply referred to as “IP”).

  As shown in FIG. 1, the main apparatus 20 includes an extension telephone accommodating I / F 21 that is an interface for accommodating each of the telephone 10, PSTN network 30, ISDN network 40, private line network 50, and LAN 60, and a PSTN line. RTP (Real-time Transport Protocol) signals exchanged between the I / F 22, ISDN line I / F 23, dedicated line I / F 24, LAN accommodating I / F 25, telephone 10 and LAN 60 are converted into voice signals or data signals. A CODEC (Coder-Decoder) circuit 26, a database 27 that holds system data to be described later for communication connection of the telephone set 10, and a control circuit 28 that controls communication of the telephone set 10 are provided.

  In communication with the LAN 60 as an IP trunk, the control circuit 28 is configured to use SIP (Session Initiation Protocol) or H.264 stored in a storage mechanism (not shown) of the main device 20. It operates along an application program that processes IP such as H.323.

  When an IP trunk is used for outgoing calls from the telephone 10, the control circuit 28 operates to bypass another communication trunk such as the PSTN network 30 when the IP trunk is unavailable. In the present embodiment, the case where the IP trunk is unavailable refers to the case where it is determined that the link of the LAN 60 is broken, the case where all the lines in the LAN 60 are “BUSY”, and the like. In addition, in order to cope with a situation in which a trapped trunk cannot be actually used due to subsequent communication congestion, a predetermined response message is obtained for the first call request message transmitted to the trunk. If not, it is determined that the IP trunk is not usable.

  Note that the response to the call request message is, for example, a 100 Trying message or 180 Ringing message for the INVITE message in SIP. In the case of the H.323 protocol, it refers to a Call Proceding message or an Alerting message for the Setup message. The control circuit 28 determines that the IP trunk is unusable when a response message cannot be received within a predetermined time after transmission of the call request message and a time-out occurs.

  FIG. 2 shows system data held in the database 27. These system data are registered in advance in the database 27 by the system administrator, for example. The system data A shown in FIG. 2 (a) includes the extension number of the telephone 10, information indicating whether or not the function of detouring to another communication trunk replacing the IP trunk is effective, and confirming the detour of the trunk with the user. The information indicating whether or not it is necessary to correspond is associated with each other. The system data B in FIG. 2 (b) indicates the association between the number assigned to each IP trunk and the group to which the number belongs.

  The system data C in FIG. 2C is detour trunk information, and is connected to the trunk group specified by the system data B, detour communication trunk information assigned to the group, and the detour trunk. The correspondence with the telephone number table for this is shown. In the illustrated example, the PSTN network 30 is set in advance as a bypass trunk.

  The system data D in FIG. 2D is detour number information, and indicates a telephone number table shown in the system data C. In the example shown in the figure, a telephone number used when making an IP call to the telephone on the called side and a PSTN call number corresponding to the telephone number for the IP call are shown. FIG. 2D shows the contents of “table 1” in the system data C as an example of the telephone number table, and the telephone numbers are set in the same format for the other telephone number tables. Has been.

  The operation of the first embodiment will be described with reference to the flowchart shown in FIG. Here, when the telephone 10 having the extension number “100” transmits the telephone number “050-1111-1111” to the IP trunk having the trunk number “1” in the LAN 60, the PSTN network 30 is used as a bypass trunk. An example is shown.

  When the control circuit 28 of the main device 20 receives a call request from the telephone 10 to the IP trunk (step S1), whether the link in the LAN 60 is broken or whether all the IP trunks in the LAN 60 are “BUSY”. Is confirmed (step S2). If it does not correspond to any of them (step S2: No), it is further confirmed whether or not a response message corresponding to the type of IP to be used is received, and when a predetermined response message is received (step S3: Yes), the telephone 10 In response to the request from the terminal, IP transmission is performed to the target IP trunk via the CODEC circuit 26 and the LAN accommodating I / F 25 (step S4).

  Further, when the link of the LAN 60 is broken or all are “BUSY” (step S2: Yes), or when a response to the call request message is not obtained (step S3: No), the system data of FIG. Referring to A, it is confirmed whether or not the bypass function of the telephone 10 is valid. Here, since the bypass function of the extension number “100” is “valid” (step S5: Yes), the control circuit 28 checks the IP trunk group to be used as shown in FIG. With reference to the system data B, information on “group 1” corresponding to the trunk number “1” is acquired (step S6). If the detour function is “invalid” as indicated by the extension number “102” (step S5: No), the control circuit 28 notifies the telephone set 10 of the result “BUSY”. The connection process is stopped (step S7).

  Subsequently, the control circuit 28 refers to the system data C in FIG. 2C, and checks whether a bypass trunk in place of the IP trunk to be used, that is, the trunk of the PSTN network 30 and its telephone number are registered. Whether or not is confirmed (steps S8 and S9). Here, the trunk number of the PSTN network 30 to be used instead of the IP trunk “group 1” is “6”, and the telephone number table for calling to this detour trunk is “table 1”. Information is obtained (steps S8, S9: Yes). If the bypass trunk and the telephone number table are not registered, the telephone 10 is notified of “BUSY” and the connection process is stopped (step S7).

  The control circuit 28 refers to the system data D in FIG. 2D corresponding to the “table 1”, and acquires a telephone number used when detouring to the PSTN network 30 (step S10). In this example, since the telephone 10 initially transmits the IP transmission number “050-1111-1111”, the PSTN transmission number “03-9999-9999” corresponding to the number is acquired from the table shown in the figure.

  When the control circuit 28 acquires the above-mentioned transmission number, prior to the transmission to the PSTN network 30, the control circuit 28 refers to the system data A to determine whether or not to confirm with the user of the telephone 10 that the communication trunk is bypassed. . In this way, by confirming whether or not detouring is possible for the user, for example, when there is a large difference in connection charges between communication trunks, it is possible to avoid detouring automatically to a trunk that increases the cost for the user. In the system data A of FIG. 2A, since the confirmation of detouring is set for the extension number “100” (step S11: Yes), a message confirming whether or not detouring to the PSTN network 30 is possible. Is transmitted to the telephone 10. As a response method of the user to this confirmation, for example, the answer can be sent by pressing a predetermined button on the telephone 10.

  When there is no need to confirm with the user regarding the detour (step S11: No), and when the detour is permitted from the user to the PSTN network 30 (step S12: Yes), the control circuit 28 performs the PSTN line I / F 22 Then, the outgoing call processing is performed (step S13). If the user cannot obtain the detour permission (step S12: No), the telephone 10 is notified of “BUSY” in order to stop the process (step S7).

  FIG. 4 schematically shows the above procedure. As described above, in the system 100, when the control circuit 28 determines that the IP trunk cannot be used when the user tries to connect to the other party's telephone 10 'via the IP trunk of the LAN 60 from the telephone 10, As a route to the main device 20 ′ on the receiving side, a detour is made to a preset trunk of the PSTN network 30. Therefore, according to the first embodiment, even when an IP trunk cannot be used, a bypass trunk can be selected quickly. Further, since the user's intention is confirmed prior to detouring, it is possible to avoid detour processing unintentional for the user.

[Example 2]
In the second embodiment of the detour control method according to the present invention, a condition relating to the voice quality of the IP trunk is taken into account when determining whether or not to detour a communication trunk. Specifically, for example, the packet drop rate in the IP trunk is used for the voice quality determination, and when the current drop rate exceeds a preset threshold, it is determined that the voice quality has deteriorated.

  In order to realize this, in this embodiment, system data as shown in FIG. The system data E shown in FIG. 5 (a) indicates the number of the QoS (Quality of Service) table used for determining the voice quality of each trunk group in FIG. 2 (b). The system data F in FIG. 5B indicates the contents of the QoS table described in the system data E. In the illustrated example, the contents of the QoS table 1 are shown as an example of the QoS table. ing. According to the determination based on this table, if the average measurement value of “past 5 times” regarding the packet drop rate exceeds the threshold value “5%” in the IP trunk of trunk group number “1”, the voice quality of the trunk is Considered degraded.

  The operation of the second embodiment will be described with reference to the flowchart of FIG. Here, similarly to the operation example in the first embodiment, the procedure is to use the IP trunk having the trunk number “1” in the LAN 60. The procedures other than the determination regarding the voice quality described above will be described with reference to FIG. The procedure is the same as that of the first embodiment, and a description thereof will be omitted. FIG. 6 mainly shows the difference from the first embodiment.

  When the control circuit 28 of the main device 20 receives a call from the telephone 10 and then obtains a predetermined response message from the supplemented IP trunk (step S3: Yes), the control circuit 28 of FIG. With reference to the system data E in (a), information is obtained that “QoS table 1” is used for voice quality determination of the IP trunk of group “1”.

  Subsequently, when the control circuit 28 refers to the system data F in FIG. 5B and compares the table with the actual measurement result, the control circuit 28 determines that the voice quality of the IP trunk has deteriorated. (Step A1: Yes), in order to make a detour to the PSTN network 30, it is determined whether or not the detour function of the telephone 10 is set (step S5). If it is determined that the packet drop rate does not exceed the threshold value and the voice quality is not deteriorated (step A1: No), the IP trunk is used to make a call (step S4). Thereafter, with respect to detouring to the PSTN network 30, processing is performed in the same procedure as in the first embodiment along FIG.

  In the above example, the packet drop rate is used to determine the voice quality. Instead, for example, a voice delay measurement value, a noise measurement value, or ITU (International Telecommunication Union) is used. The voice quality may be determined using a recommended evaluation value such as a MOS value or an R value.

  As described above, according to the second embodiment, since the procedure for determining the voice quality is added before the call to the IP trunk is determined, the call is transmitted using the IP trunk having the voice quality deteriorated. This can be prevented.

  In each of the above embodiments, a PSTN trunk is set as a bypass trunk instead of an IP trunk. However, the present invention is not limited to this example, and other communication networks such as the ISDN network 40 and the dedicated line network 50 shown in FIG. The trunk in can be set for detour.

  The present invention is also applicable to a program that causes a computer to execute the procedure described in the first and second embodiments and a recording medium that records the program.

1 is a block diagram of a system to which a first embodiment of a detour control method according to the present invention is applied. FIG. 4 is an explanatory diagram for explaining system data according to the first embodiment. 3 is a flowchart illustrating the operation of the first embodiment. FIG. 6 is an explanatory diagram for schematically explaining the operation of the first embodiment. FIG. 6 is an explanatory diagram for explaining system data of a second embodiment. 10 is a flowchart showing the operation of the second embodiment.

Explanation of symbols

100 System 10 Telephone 20 Main Device 30 PSTN Network 40 ISDN Network 50 Private Line Network 60 LAN
21: Extension telephone accommodation I / F, 22: PSTN line I / F, 23: ISDN line I / F, 24: Dedicated line I / F, 25: LAN accommodation I / F

Claims (9)

A method for controlling the bypass of a communication trunk in a control device accommodating a telephone and a plurality of communication trunks including an IP trunk for the telephone,
Detour trunk information indicating a correspondence relationship between a detour trunk, which is a predetermined communication trunk other than an IP trunk among the plurality of communication trunks, and the telephone, and a detour indicating a telephone number for connecting to the detour trunk Set the number information,
Determining whether or not the IP trunk can be used when there is a call request from the telephone to the IP trunk;
When it is determined that the IP trunk is unusable, a bypass trunk corresponding to the telephone is selected based on the bypass trunk information,
Obtaining a telephone number for the selected bypass trunk from the bypass number information;
A detour control method comprising connecting the telephone to the detour trunk by the acquired telephone number. Furthermore, the quality judgment information indicating the judgment condition of the voice quality of the IP trunk is set,
When it is determined that the IP trunk is usable in the determination, the voice quality of the IP trunk is determined based on the quality determination information,
2. The bypass control method according to claim 1, wherein the bypass trunk is selected when it is determined that the voice quality is deteriorated.   When a call request is made from the telephone to the IP trunk, a predetermined call request message is sent to the IP trunk, and the IP trunk cannot be used if a timeout occurs before receiving the predetermined response message for the call request message. The detour control method according to claim 1, wherein the detour control method is determined.   The detour control method according to any one of claims 1 to 3, wherein the user is inquired of whether or not detouring to the trunk is possible before the telephone is connected to the detouring trunk. A program for controlling a bypass of a communication trunk in a control device that accommodates a telephone and a plurality of communication trunks including an IP trunk for the telephone,
Detour trunk information indicating a correspondence relationship between a detour trunk, which is a predetermined communication trunk other than an IP trunk among the plurality of communication trunks, and the telephone, and a detour indicating a telephone number for connecting to the detour trunk Set the number information,
Determining whether or not the IP trunk can be used when there is a call request from the telephone to the IP trunk;
When it is determined that the IP trunk is unusable, a bypass trunk corresponding to the telephone is selected based on the bypass trunk information,
Obtaining a telephone number for the selected bypass trunk from the bypass number information;
A bypass control program that causes the control device to execute connection of the telephone to the bypass trunk by the acquired telephone number. Furthermore, the quality judgment information indicating the judgment condition of the voice quality of the IP trunk is set,
When it is determined that the IP trunk is usable in the determination, the voice quality of the IP trunk is determined based on the quality determination information,
6. The bypass control program according to claim 5, wherein when the voice quality is determined to be deteriorated, the control device is caused to execute the selection of the bypass trunk.   When a call request is made from the telephone to the IP trunk, a predetermined call request message is sent to the IP trunk, and the IP trunk cannot be used if a timeout occurs before receiving the predetermined response message for the call request message. The detour control program according to claim 5 or 6, wherein the control device is caused to execute the determination that it is.   8. The control device according to claim 5, wherein, prior to connecting the telephone to the bypass trunk, the control device is configured to inquire a user about whether or not the trunk can be bypassed. Detour control program.   9. A recording medium on which the detour control program according to claim 5 is recorded.

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