JP4765438B2 - IP-PBX system - Google Patents

Description

  The present invention relates to an IP-PBX system, and can be applied to, for example, a system having a satellite control device at a position far from the installation position of the PBX main body.

  In recent years, IP telephones have become widespread, and data and voice can be integrated on the LAN to benefit from IP. In addition, there is a system that receives the same benefit by installing an IP telephone in a remote place from the PBX main body and centrally managing it from the PBX main body using the IP network. That is, there is a system in which a remote IP telephone is a component of the PBX system. Note that the term “IP telephone” in this specification is a generic term for not only a pure IP telephone but also a terminal that performs communication via an IP-FAX or other IP network.

  FIG. 2 is a block diagram showing a configuration example of a conventional IP-PBX system when an IP telephone is installed at a remote site.

  In FIG. 2, a PBX main unit 1 is connected to an IP network 4 via a router (R) 3-1, and one or a plurality (three in FIG. 2) of IP telephones 2-1 to 2-3 at a remote base are Are accommodated in a hub (HUB) 5 and connected to an IP network (for example, an IP-VPN network (carrier network)) 4 via a router (R) 3-2.

  The PBX main body 1 has an IP telephone control board (IPDLC; IP data link controller) 6. The IPDLC 6 controls the subordinate IP telephones (for example, 32 units), and controls the control packet / between the PBX main body 1 and the IP telephone. Mediates voice packets. The same applies to the case where IP telephones 2-1 to 2-3 as shown in FIG. 2 are installed at remote locations, and a carrier network (for example, an IP-VPN network) between IP DLC 6 and IP telephones 2-1 to 2-3 Even if there is a network, communication between the IPDLC 6 and the IP telephones 2-1 to 2-3 can be realized by installing IP switching devices such as the routers 3-1, 3-2.

  FIG. 3 is a block diagram showing a configuration example of a conventional IP-PBX system in which terminals other than IP telephones are extension components, and the same and corresponding parts as those in FIG. Show.

  In FIG. 3, a satellite control unit (IPLTU) 7 accommodated in a hub 5-2 (same as the hub 5 in FIG. 2) is an IP telephone that cannot be controlled by IP, such as an analog telephone 8 or a PHS terminal, at a remote location. It has a function of accommodating and controlling one or a plurality of terminals other than those, and communicates with the PBX main body 1 using IP packets. Although not shown in the figure, the IPLTU 7 has a built-in switch unit and controls connection between the accommodation devices.

  Here, when viewed from the PBX main unit 1, the remote IP phones 2-1 to 2-3 and the IPLTU 7 perform control and communication using the same IP packet, but the terminal accommodated by the IPLTU 7 is other than the IP phone. In this case, since the processing after disassembling the IP packet cannot all be made the same, the IP telephones 2-1 to 2-3 and the IPLTU 7 are not interfered with each other and managed and controlled completely. That is, the PBX main body 1 includes a voice interface board (CVIT) 9 for the satellite control device and a control information interface board (RLCPA) 10 for the satellite control device. The IPLTU 7 is connected via the interface boards 9 and 10. Management and control.

  Although omitted in FIGS. 2 and 3, the PBX main body 1 naturally includes a call processing control unit and a switch unit.

In addition, the IP-PBX main unit and a terminal device at a remote user base are connected via a dedicated line by a LAN connection device provided at both locations to provide a wide-area IP-PBX system. This has also been proposed (Patent Document 1).
JP 2003-70035 A

  The disclosed technology of Patent Document 1 is limited to IP telephones as extension components, and existing analog telephones and PHS terminals cannot be applied as extension components at remote locations.

  By the way, as shown in FIG. 2 and FIG. 3, the satellite control device 7 that accommodates the IP telephone 2 (2-1 to 2-3), an analog telephone that behaves like an IP telephone, and the like communicates with the PBX main body 1. The total bandwidth required for the control is about 1 kbps for control packets and about 27 kbps for voice packets (when using G.729 compression and a packet period of 20 ms). Therefore, when many of the devices installed at remote locations communicate with the PBX main unit 1, the necessary bandwidth is considerably large. Considering such a case, the user associated with the IP-PBX system Has to define a contract bandwidth with the operator (carrier) of the IP network, and the usage fee for the IP network is considerably high.

  Therefore, there is a demand for an IP-PBX system that can suppress as much as possible the communication capacity via the IP network per PBX main unit and one remote extension terminal.

In order to solve this problem, the present invention communicates with a PBX main body accommodating a plurality of extension terminals and the PBX main body via an IP network in an IP-PBX system using at least an IP telephone as an extension terminal. A satellite control device that accommodates a plurality of extension terminals including IP telephones that are located at remote locations, and (1) the satellite control device controls (1-1) the IP phone that is accommodated, IP telephone control means for realizing a voice call of the accommodated IP telephone, and (1-2) an extension terminal that executes an interface with the IP network side and includes a switch and is accommodated in the satellite control apparatus IP line trunk unit means for setting up a communication path between them and (1-3) non-IP telephones accommodated by the satellite control device A non-IP line controller means for interconverting signals into signals that can pass through the IP network, and (2) the PBX main unit establishes a call between the two extension terminals accommodated by the satellite control device And remote switch setting control means for instructing the switching setting for connecting the two extension terminals not via the IP network to establish the speech path when the switch is required. To do.

  According to the IP-PBX system of the present invention, since the satellite control apparatus accommodates remote extension terminals including the IP telephone, the control function of the satellite control apparatus allows the PBX main unit and the remote installation equipment to The communication capacity via the IP network can be reduced.

(A) Embodiment Hereinafter, an embodiment of an IP-PBX system according to the present invention will be described in detail with reference to the drawings.

(A-1) Configuration of Embodiment FIG. 1 is a block diagram showing the configuration of the IP-PBX system of this embodiment, and the same reference numerals are given to the same and corresponding parts as in FIG. It is a thing.

  In FIG. 1, in the IP-PBX system of this embodiment, a hub 5-2 that accommodates remote IP telephones 2-1 to 2-3 is accommodated in a satellite control device 7, and the satellite control device 7 is a router. It is connected to the IP network 4 via 3-2. The satellite control device 7 has a function of accommodating and controlling one or a plurality of terminals other than the IP telephone that cannot be controlled by the IP, as in the conventional case. In addition, the satellite control device 7 of this embodiment accommodates the IP telephones 2-1 to 2-3 although it is via the hub 5-2, and therefore, the IP telephone control board (IPDLC; IP data link). Controller) 6.

  On the other hand, the PBX main body 1 includes a board (RLCPA) 10 for controlling the satellite control device 7 and a board (CVIT) 9 for realizing a voice call path between the PBX main body 1 and the satellite control device 7. Unlike the IP telephone control board (IPDLC) for controlling the remote IP telephones 2-1 to 2-3. The two substrates 9 and 10 described above are concentrated by the hub 5-1, and then connected to the IP network 4 via the router 3-1.

  An IP switching device (for example, a switching HUB) may be connected between the PBX main body 1 and the router 3-1, or between the router 3-2 and the satellite control device 7.

  FIG. 4 is a block diagram showing a schematic configuration example of the interior of the satellite control device 7 of this embodiment.

  4, the satellite control device 7 includes an IP line trunk unit board (IPLTU) 30 and an analog line controller board (ALC) 40 in addition to the IPDLC 6 (shown by reference numeral 20 in FIG. 4) as described above.

  The IPDLC 20 includes a CPU (here, a concept including a program memory and a working memory) 21 and a LAN controller (LANC) 22. The CPU 21 is connected to an internal bus 50 including a control bus and a speech path bus, and the CPU 21 is connected to the hub 5. -2 to control the IP telephones 2-1 to 2-3 accommodated through the terminal -2 and realize a voice call.

  The IPLTU 30 includes a CPU 31, a LANC 32, and a switch (SW) 33, executes an interface with the IP network 4 side, and sets a communication path between terminal devices accommodated in the satellite control device 7. It is. Here, the CPU 31 performs multiplexing and demultiplexing of a plurality of channels as will be described later in the description of the operation.

  The ALC 40 includes a CPU 41, a codec section 42, and an analog telephone interface 43, and executes mutual conversion between signals exchanged with the analog telephone 8 and IP packets. When there are a plurality of analog telephones 8, a set of the codec unit 42 and the analog telephone interface 43 or a plurality of analog telephone interfaces 43 (in this case, the codec unit 42 is common) may be provided. If the accommodation terminal other than the IP telephone is a portable terminal, an interface or codec for that purpose may be provided.

(A-2) Operation | movement of embodiment Next, operation | movement of the IP-PBX system of embodiment which has the above structures is demonstrated.

  In the following, the IP telephone housed in the satellite control device 7 via the hub 5-2 (herein referred to as the IP telephone set 2-1) and the satellite control device 7 performing the characteristic operation in this embodiment. An outline of a call operation between remote extension terminals with the analog telephone 8 accommodated in the telephone will be described with reference to the sequence diagram of FIG. In FIG. 5, the acknowledge signal is omitted.

  When the IP telephone 2-1 dials the extension number of the analog telephone 8, a signaling signal indicating a call originating at the analog telephone 8 is given to the satellite control device 7 (IPDLC 6) via the hub 5-2. At this time, the satellite control device 7 transmits a call request (signaling signal) destined for the analog telephone 8 to the PBX main unit 1 (step 101).

  In the PBX main body 1, the RLCPA board 10 has a control interface with the satellite control device 7 side, and the call request is given to the call processing control unit 50 via the RLCPA board 10, and the call processing control is performed. The unit 50 is a terminal accommodated in the satellite control device 7 for both the call source terminal and the call destination terminal, so the communication path between the IP telephone set 2-1 and the analog telephone set 8 is connected to the satellite control device 7. Instruct the switching setting to establish (step 102). In the satellite control device 7, the instructed switching setting is performed on the switch 33 of the IPLTU 30.

The call processing control unit 50 of the PBX main body 1 automatically gives a switching setting instruction or when a reply indicating that the switching setting has been made is given from the satellite control device 7 (omitted in FIG. 5), the satellite control device 7 On the other hand, an incoming call request to the analog telephone 8 is sent (step 103). At this time, the satellite control device 7 performs an incoming call process (for example, ringing of the ringer) to the analog telephone 8 via the ALC 40 (step 104), and the analog telephone 8 responds (for example, off-hook). Then, the state shifts to a call state between the IP telephone set 2-1 and the analog telephone set 8 (step 105).

  Although omitted in FIG. 5, the satellite control device 7 notifies the PBX main unit 1 that the IP telephone set 2-1 and the analog telephone set 8 have transitioned to a call state, or the transition has been made, and the IP telephone set. The PBX main body 1 manages the state of the 2-1 and the analog telephone 8 as a call state.

  FIG. 6 shows an image of a speech path established by the process of FIG. As described above, control for establishing a call between remote extension terminals is executed by the PBX main unit 1, but the communication path does not go through the PBX main unit 1, in other words, the IP network 4. It is formed without intervention.

FIG. 7 is a sequence diagram showing a call establishing operation between remote extension terminals in the prior art shown in FIG. 3, corresponding to FIG. 5 according to the embodiment, and FIG. 7 shows an image of a speech path established by the process of No. 7 . In the conventional case, even when a call between remote extension terminals is established, a switching path is set for the switch 51 in the PBX main body 1 to form a communication path, so the communication path passes through the PBX main body 1. In other words, it is via the IP network 4.

  Although an operation sequence diagram is omitted, when an on-hook occurs in one of the IP telephone set 2-1 and the analog telephone set 8 in a call state, the setting of the switch 33 related to the call path in the satellite control device 7 is canceled, This is notified to the other, and when the other also changes to on-hook, this is notified to the PBX main body 1. Thereby, the call processing control unit 50 of the PBX main body 1 recognizes that the switching setting has been canceled.

  In the above, the calls of the IP telephone set 2-1 and the analog telephone 8 have been described, but the same applies to calls between other extension terminals at remote locations. For example, for calls in the case of the IP telephones 2-1 and 2-2, the call processing is controlled by the PBX main body 1, and the communication path formed thereby does not pass through the PBX main body 1. Further, for example, when there are two analog telephones 8 accommodated in the satellite control device 7, the call processing between the two analog telephones 8 is controlled by the PBX main body 1, and the communication path formed thereby Does not pass through the PBX main body 1.

  FIG. 9 is an explanatory diagram showing a configuration of a voice IP packet exchanged between the PBX main body 1 and the satellite control device 7 of this embodiment.

  The IP packet for audio exchanged between the PBX main body 1 and the satellite control device 7 of this embodiment is not the audio data for one channel in the payload following the header composed of the IP header, UDP header, RTP header, etc. Voice data for the number of channels equal to the maximum number of extension terminals that can be accommodated by the satellite control device 7 is inserted. FIG. 9 shows a case where the maximum number of extension terminals is 32, although it does not coincide with FIG. The audio data of each channel inserted into the payload is, for example, G. 729 (8 kpbs compression). Note that voice data for the maximum number of extension terminals can be inserted into the payload, but the number of channels inserted at the time of communication is the number of channels for which the communication path is established at that time (below the maximum number of extension terminals). is there. However, the maximum is 1546 bytes per packet.

  The voice interface board (CVIT) 9 for the satellite control device in the PBX main body 1 and the IPUTU 30 in the satellite control device 7 have functions of assembling such multi-channel IP packets and disassembling the IP packets. . The header of the voice IP packet shown in FIG. 9 is such that the IP packet can be exchanged between the CVIT 9 and the IPUTU 30.

For example, an IP telephone or an analog telephone (hereinafter referred to as a remote extension terminal X) accommodated in the satellite control device 7 and an IP telephone or an analog telephone (hereinafter referred to as a central extension terminal Y) accommodated in the PBX main body 1 Call), the call processing control unit 50 of the PBX main body 1 determines one of the 32 channels as a use channel in the call path establishing operation. Such a determination channel is notified to the CVIT 9 of the PBX main body 1 and the IPLTU 30 of the satellite control device 7 to establish a call path.

If the remote extension terminal X is an IP telephone, the IPLTU 30 is provided with the IP packet for voice from the remote extension terminal X via the IPDLC 20, and the voice data portion is extracted and compressed. 9 is inserted into the corresponding channel portion, and the inserted IP packet is sent to the PBX main body 1. Conversely, when the IP packet reaches the IPLTU 30 from the PBX main body 1, the IPLTU 30 Is extracted and decompressed to form an IP packet with header information (internally managed by the CPU 31) corresponding to the insertion position of the channel, and the IP packet is received via the IPDLC 20 as appropriate. Send to IP phone.

If the remote extension terminal X is the analog telephone 8, the ALC 40 performs the decomposition of the IP packet of the voice signal from the analog telephone 8 and the IP packet to the analog telephone 8, but the IPLTU 30 executes a plurality of The assembly of the IP packet in which the voice data of the IP packet is multiplexed and the disassembly of the plurality of IP packets of the IP packet in which the voice data is multiplexed are the same as in the case where the remote extension terminal X is an IP telephone.

For example, the CPU 31 in the IPLTU 30 performs software assembly of the IP packet in which the voice data of the plurality of IP packets is multiplexed as described above and the disassembly processing of the plurality of IP packets in which the voice data is multiplexed. To do.

The CVIT 9 of the PBX main body 1 performs the same processing as the IPLTU 30 of the satellite control device 7 for the extension terminal accommodated in the PBX main body 1. An IP packet in which voice data of IP packets from one or more accommodated extension terminals is multiplexed is assembled and sent to the satellite control device 7, and the IP packet multiplexed with voice data from the satellite control device 7 side It is decomposed into one or a plurality of IP packets and distributed to the extension terminals accommodated in the PBX main body 1 via the switch 51.

(A-3) Effect of Embodiment According to the IP-PBX system of the above embodiment, the PBX main body and one extension component at a remote location are connected via the IP network for the following reasons (1) and (2). It was the communication capacity can be suppressed compared with the conventional, so that the user can suppress the bandwidth promises carrier and contract, can lead to cost reduction.

  (1) Although the PBX main body 1 is involved in establishing a communication path between remote extension terminals, the communication path itself is established by a switch in the satellite control apparatus so as not to pass through the IP network. The communication capacity at is 0.

  (2) In addition to accommodating the IP telephone in the satellite control device, the voice data exchanged between the accommodated extension terminal of the PBX main body and the accommodated extension terminal of the satellite control device is multiplexed on the payload of the same IP packet. Since the communication is performed, the communication capacity in the IP network can be reduced more than in the past.

  For example, there are 32 IP telephones under the satellite control device 7, and all IP telephones Consider the case where a call is made to an extension terminal accommodated in the PBX main body 1 using 729 compression. G. 729 is compressed to 8 kpbs, so 8 kbit / 1S per call. If the packetization period is 20 ms, one packetization period per call is 160 bits / 20 ms, and 32 calls is 5120 bits / 20 ms. Since 5120 bits is 640 bytes, an IP header 40 bytes is added thereto, which is 680 bytes / 20 ms. At this communication speed, the required bandwidth between 1S is 34000 Bytes / 1s, which is 272 kbps. The necessary bandwidth for control is added to this and becomes 273 kbps, which becomes the necessary bandwidth in the IP network.

  In the case of the conventional system of FIG. 3, although the detailed description is avoided, the necessary bandwidth is 896 kbps, which is a reduction of 623 kbps.

  Since the IP telephone is capable of transmitting and receiving IP packets, it is not necessarily required to be accommodated in the satellite control device 7. However, in this embodiment, in order to realize the above (1) and (2), The IP telephone is accommodated in the satellite control device 7.

(B) Other Embodiments In the above-described embodiment, the case where there is one satellite control device is shown, but two or more satellite control devices may exist. Even in this case, communication of audio data between the PBX main body and each satellite control device is performed by time division multiplexing as described above. Further, a call between the accommodation extension terminal of the first satellite control device and the accommodation extension terminal of the second satellite control device is performed via the PBX main body, and a call between the first satellite control device and the PBX main body, The call method of the above-described embodiment may be applied to a call between the satellite control device 2 and the PBX main body.

  In the description of the above embodiment, G. 729, but if it can be unified throughout the system, G. 711 and G.G. Other compression methods such as 723 may be applied.

It is a block diagram which shows the structure of the IP-PBX system of embodiment. It is a block diagram which shows the structural example (1) of the conventional IP-PBX system. It is a block diagram which shows the structural example (2) of the conventional IP-PBX system. It is a block diagram which shows the schematic internal structure of the satellite control apparatus of embodiment. It is a sequence diagram which shows the call establishment operation | movement between the extension terminals of the remote place of embodiment. It is explanatory drawing which shows the image of the speech path formed by the operation | movement of FIG. FIG. 4 is a sequence diagram showing a call establishment operation between remote extension terminals in the conventional example of FIG. 3. It is explanatory drawing which shows the image of the speech path formed by the operation | movement of FIG. It is explanatory drawing which shows the structure of the IP packet transmitted / received between the PBX main body and satellite control apparatus of embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... PBX main body, 2-1 to 2-3 ... IP telephone is 3-1, 3-2 ... Router (R), 4 ... IP network, 5-1, 5-2 ... Hub (HUB) , 6 ... IP telephone control board (IPDLC) , 7 ... satellite control apparatus, 8 ... analog telephone, 9 ... voice interface board (CVIT) for satellite control apparatus, 10 ... control information interface board (RLCPA) for satellite control apparatus.

Claims (2)

In an IP-PBX system using at least an IP telephone as an extension terminal,
A PBX body containing a plurality of extension terminals;
A satellite control device that accommodates a plurality of extension terminals including IP telephones, which are arranged at remote locations communicating with the PBX main unit via an IP network ,
The satellite control device is
IP telephone control means for controlling the accommodated IP telephone and realizing voice call of the accommodated IP telephone;
An IP line trunk unit means for executing an interface with the IP network side and having a switch to set a communication path between extension terminals accommodated in the satellite control device;
Non-IP line controller means for mutually converting a signal to be exchanged with a non-IP telephone housed in the satellite control device into a signal that can pass through an IP network,
When the PBX main body needs to establish a call between the two extension terminals accommodated by the satellite control device, the PBX main unit connects the two extension terminals not via the IP network to the switch. An IP-PBX system comprising remote switch setting control means for instructing switching settings and establishing a communication path . The PBX main body and the satellite control device each have channel multiplexed IP packet assembling / disassembling means for assembling or disassembling channel multiplexed IP packets into which a plurality of channels of audio data are inserted, and between the PBX main body and the satellite control device. 2. The IP-PBX system according to claim 1, wherein the data transmission / reception of the communication channel via the IP network is performed by channel multiplexed IP packets.

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