JPH10271243A - Lan telephone set - Google Patents

Lan telephone set

Info

Publication number
JPH10271243A
JPH10271243A JP9087500A JP8750097A JPH10271243A JP H10271243 A JPH10271243 A JP H10271243A JP 9087500 A JP9087500 A JP 9087500A JP 8750097 A JP8750097 A JP 8750097A JP H10271243 A JPH10271243 A JP H10271243A
Authority
JP
Japan
Prior art keywords
lan
telephone network
public telephone
failure
pstn
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
JP9087500A
Other languages
Japanese (ja)
Inventor
Shuzo Ishii
秀三 石井
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Victor Company of Japan Ltd
Original Assignee
Victor Company of Japan Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Victor Company of Japan Ltd filed Critical Victor Company of Japan Ltd
Priority to JP9087500A priority Critical patent/JPH10271243A/en
Publication of JPH10271243A publication Critical patent/JPH10271243A/en
Withdrawn legal-status Critical Current

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  • Small-Scale Networks (AREA)
  • Telephonic Communication Services (AREA)

Abstract

PROBLEM TO BE SOLVED: To provide a LAN(local area network) telephone set capable of being serviced to a line wire even in the case of the occurrence of a fault in a LAN or the service interruption of a commercial power supply system. SOLUTION: A LAN interface circuit part 120 periodically monitors a state inquiry packet from a LAN private branch exchange; and if it does not receive this state inquiry packet, it discriminates the occurrence of a fault in the LAN and switches a relay 141 from a terminal A (ADPCM encoding/decoding part 121) to a terminal B (PSTN public switching telephone network) by the control signal,. The relay 141 switches a service interface part 142 to PSTN at the time of power failure of a commercial power.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、LAN(ローカル
エリアネットワーク)構内交換ネットワークにおけるL
AN電話機に関する。
[0001] The present invention relates to a LAN (Local Area Network) private branch exchange network.
Related to AN telephone.

【0002】[0002]

【従来の技術】一般に、LANを構内交換網としてLA
N電話機を内線電話機として用いるとともに、公衆網で
あるISDN(統合サービスデジタル網)やPSTN
(公衆交換電話網)が外線として接続されたLAN構内
交換ネットワークが知られている。
2. Description of the Related Art Generally, a local area network (LAN) is
N telephones are used as extension telephones, and public networks such as ISDN (Integrated Services Digital Network) and PSTN
2. Description of the Related Art A LAN private branch exchange network to which a public switched telephone network is connected as an outside line is known.

【0003】[0003]

【発明が解決しようとする課題】しかしながら、従来の
LAN電話機では、LANに障害が発生すると内線通話
はもちろん、外線通話が不可能になるという問題点があ
る。また、LAN電話機は通常、PSTNから電源を供
給されるPSTN電話機と異なり、商用電源から電源を
供給されるので、停電時に外線通話が不可能になるとい
う問題点がある。
However, the conventional LAN telephone has a problem in that when a failure occurs in the LAN, not only internal telephone calls but also external telephone calls become impossible. Also, unlike a PSTN telephone that is normally supplied with power from a PSTN, a LAN telephone is supplied with power from a commercial power supply, so that there is a problem in that external telephone calls cannot be made during a power failure.

【0004】本発明は上記従来の問題点に鑑み、LAN
に障害が発生しても外線通話が可能なLAN電話機を提
供することを目的とする。本発明はまた、商用電源が停
電しても外線通話が可能なLAN電話機を提供すること
を目的とする。
The present invention has been made in view of the above-mentioned conventional problems, and
It is an object of the present invention to provide a LAN telephone capable of making an external call even if a failure occurs in the telephone. Another object of the present invention is to provide a LAN telephone capable of making an outside-line call even when a commercial power supply is interrupted.

【0005】[0005]

【課題を解決するための手段】本発明は上記目的を達成
するために、公衆電話網との呼制御及び通信制御を行う
公衆電話網インタフェースを設けるとともに、LAN上
の障害を検出した場合に通話路をLANから公衆電話網
インタフェースに切り換えるようにしたものである。本
発明はまた、公衆電話網との呼制御及び通信制御を行う
公衆電話網インタフェースを設けるとともに、商用電源
の停電時に通話路をLANから公衆電話網インタフェー
スに切り換えるようにしたものである。
SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a public telephone network interface for performing call control and communication control with a public telephone network, and performs communication when a failure on a LAN is detected. The route is switched from the LAN to the public telephone network interface. The present invention further provides a public telephone network interface for performing call control and communication control with the public telephone network, and switches a communication path from a LAN to a public telephone network interface when a commercial power supply is interrupted.

【0006】すなわち本発明によれば、LAN上の障害
を検出する障害検出手段と、公衆電話網との呼制御及び
通信制御を行う公衆電話網インタフェースと、前記障害
検出手段が前記LAN上の障害を検出した場合に通話路
を前記LANから前記公衆電話網インタフェースに切り
換える回線切り換え手段とを、有するLAN電話機が提
供される。
That is, according to the present invention, a fault detecting means for detecting a fault on a LAN, a public telephone network interface for performing call control and communication control with a public telephone network, and the fault detecting means comprising: And a line switching means for switching a communication path from the LAN to the public telephone network interface when the telephone line is detected.

【0007】また、本発明によれば、商用電源の停電を
検出する停電検出手段と、公衆電話網との呼制御及び通
信制御を行う公衆電話網インタフェースと、前記停電検
出手段が商用電源の停電を検出した場合に通話路をLA
Nから前記公衆電話網インタフェースに切り換える回線
切り換え手段とを、有するLAN電話機が提供される。
Further, according to the present invention, a power failure detection means for detecting a power failure of a commercial power supply, a public telephone network interface for performing call control and communication control with a public telephone network, and the power failure detection means comprising a power failure of a commercial power supply LA is detected when a call is detected
And a line switching means for switching from N to the public telephone network interface.

【0008】また、本発明によれば、LAN上の障害を
検出する障害検出手段と、商用電源の停電を検出する停
電検出手段と、公衆電話網との呼制御及び通信制御を行
う公衆電話網インタフェースと、前記障害検出手段が前
記LAN上の障害を検出した場合、又は前記停電検出手
段が商用電源の停電を検出した場合に通話路を前記LA
Nから前記公衆電話網インタフェースに切り換える回線
切り換え手段とを、有するLAN電話機が提供される。
According to the present invention, a fault detecting means for detecting a fault on a LAN, a power failure detecting means for detecting a power failure of a commercial power supply, and a public telephone network for performing call control and communication control with a public telephone network. When the fault detecting means detects a fault on the LAN, or when the power failure detecting means detects a power failure of the commercial power supply, the communication path is switched to the LA.
And a line switching means for switching from N to the public telephone network interface.

【0009】[0009]

【発明の実施の形態】以下、図面を参照して本発明の実
施の形態を説明する。図1は本発明に係るLAN電話機
の一実施の形態が適用されたLAN(ローカルエリアネ
ットワーク)構内交換ネットワークを示すブロック図、
図2は図1のPSTN対応のLAN電話機を詳細に示す
ブロック図である。
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a LAN (Local Area Network) private branch exchange network to which an embodiment of a LAN telephone according to the present invention is applied;
FIG. 2 is a block diagram showing the PSTN-compatible LAN telephone of FIG. 1 in detail.

【0010】図1に示すLAN1は例えば10BASE
−Tなどのケーブルで構成されたネットワークであり、
このLAN1上の音声信号はADPCMやLD CEL
P(G.728)などの符号音声信号を含む音声パケッ
トで送信される。LAN1には、内線電話端末であるL
AN電話機10−1、10−2、10−3と、端末装置
であるISDN(統合サービスデジタル網)ゲートウェ
イ13及びPSTN(公衆交換電話網)ゲートウェイ1
5と、LAN1の交換制御を行うLAN構内交換機17
が接続されている。
[0010] The LAN 1 shown in FIG.
-T is a network composed of cables such as
The audio signal on LAN1 is ADPCM or LD CEL
P (G.728) or the like is transmitted in a voice packet including a code voice signal. LAN1 has an extension telephone terminal L
AN telephones 10-1, 10-2, and 10-3, ISDN (Integrated Services Digital Network) gateway 13 and PSTN (Public Switched Telephone Network) gateway 1 as terminal devices
5 and a LAN private branch exchange 17 for controlling exchange of the LAN 1
Is connected.

【0011】ISDNゲートウェイ13はデジタル公衆
通信網であるISDN30とLAN1の間のプロトコル
変換を行い、PSTNゲートウェイ15はアナログ電話
網であるPSTN31とLAN1の間のプロトコル変換
を行う。また、この例では、LAN電話機10−2、1
0−3がそれぞれPSTN31とISDN30が接続さ
れている。
The ISDN gateway 13 performs a protocol conversion between the ISDN 30 which is a digital public communication network and the LAN 1, and the PSTN gateway 15 performs a protocol conversion between the PSTN 31 which is an analog telephone network and the LAN 1. Also, in this example, the LAN telephones 10-2, 1
0 to 3 are connected to the PSTN 31 and the ISDN 30, respectively.

【0012】図2はPSTN対応のLAN電話機10−
2を示し、このLAN電話機10−2は外部機器とのイ
ンタフェースとして、LAN1との間で呼制御パケット
と音声パケットを含むLANパケットを入出力するため
のLANインタフェース101と、商用電源から給電さ
れる商用電源コネクタ102と、LAN1の障害時及び
商用電源の停電時のバックアップ用としてPSTN31
に接続されるPSTNインタフェース103と、ハンド
セット10aに接続されるハンドセットインタフェース
104を有する。
FIG. 2 shows a PSTN-compatible LAN telephone 10-.
2, the LAN telephone 10-2 is supplied with power from a commercial power supply, and a LAN interface 101 for inputting / outputting a LAN packet including a call control packet and a voice packet from / to the LAN 1 as an interface with an external device. A commercial power supply connector 102 and a PSTN 31 as a backup for when a failure occurs in the LAN 1 or when a commercial power outage occurs.
And a handset interface 104 connected to the handset 10a.

【0013】LANインタフェース回路部120は制御
CPUを有し、LAN1の制御や、LAN1及びLAN
インタフェース101を介して入出力するLANパケッ
トの解析などを行う。ADPCM符号化/復号化部12
1はリレー141の端子Aからのアナログの送信音声信
号をADPCM符号化してLANインタフェース回路部
120に送信するとともに、LANインタフェース回路
部120を介して受信したADPCM符号をアナログの
音声信号に復号化してリレー141の端子Aに出力す
る。電源部122は商用電源コネクタ102を介して給
電された交流の商用電源を整流して定電圧化し、LAN
インタフェース回路部120、ADPCM符号化/復号
化部121、電源管理部140などに必要な電源を供給
する。
The LAN interface circuit section 120 has a control CPU for controlling the LAN 1 and for controlling the LAN 1 and the LAN.
Analysis of LAN packets input / output via the interface 101 is performed. ADPCM encoding / decoding unit 12
Reference numeral 1 denotes an ADPCM encoding of the analog transmission audio signal from the terminal A of the relay 141 and transmission to the LAN interface circuit unit 120, and decoding of the ADPCM code received via the LAN interface circuit unit 120 into an analog audio signal. Output to terminal A of relay 141. The power supply unit 122 rectifies the AC commercial power supplied through the commercial power connector 102 to a constant voltage,
It supplies necessary power to the interface circuit unit 120, the ADPCM encoding / decoding unit 121, the power management unit 140, and the like.

【0014】PSTNインタフェース103にはPST
N回線収容部130を介してリレー141の端子Bが接
続されている。PSTN回線収容部130はPSTN3
1の網制御(回線の閉結、ダイヤル信号の送出)を行っ
たり、回線インピーダンスを終端したり、PSTN31
の局給電による直流電源を取り出したり、PSTN31
から入力されるアナログ音声信号をリレー141の端子
Bに出力したり、リレー141の端子Bからのアナログ
音声信号をPSTN31に出力する。リレー141の共
通端子とハンドセットインタフェース104の間には通
話インタフェース部142が接続されている。
The PSTN interface 103 has a PST
Terminal B of relay 141 is connected via N line accommodating section 130. PSTN line accommodating section 130 is PSTN3
1 to control the network (close the line, send dial signal), terminate the line impedance,
To take out the DC power supply by the station power supply of PSTN31
The analog audio signal input from the relay 141 is output to the terminal B of the relay 141, and the analog audio signal from the terminal B of the relay 141 is output to the PSTN 31. A communication interface unit 142 is connected between the common terminal of the relay 141 and the handset interface 104.

【0015】電源管理部140は電源部122又はPS
TN回線収容部130からの電源を通話インタフェース
部142に必要な電源を供給するとともに、電源部12
2から電源を供給されているときにリレー141のコイ
ル(図示省略)に対してリレー141を駆動するための
信号 を供給する(信号 は電源部により生成され
たDC電源を検出した結果を示している)。リレー14
1は電源管理部140から信号 が供給されていない
場合、すなわち商用電源の停電時には通話インタフェー
ス部142を端子B側、すなわちPSTN回線収容部1
30側に接続し、信号 が供給されている場合、すな
わち商用電源から給電されているときには通話インタフ
ェース部142を端子A側、すなわちADPCM符号化
/復号化部121側に接続するように構成されている。
The power management section 140 is provided with the power section 122 or the PS
The power supply from the TN line accommodating section 130 supplies necessary power to the call interface section 142 and the power supply section 12
2 supplies a signal for driving the relay 141 to a coil (not shown) of the relay 141 when the power is supplied from the power supply 2 (the signal indicates a result of detecting the DC power generated by the power supply unit). There). Relay 14
1, when the signal is not supplied from the power management unit 140, that is, at the time of a commercial power failure, the communication interface unit 142 is connected to the terminal B side, that is, the PSTN line accommodation unit 1
When the signal is supplied, that is, when the power is supplied from the commercial power supply, the communication interface unit 142 is connected to the terminal A side, that is, the ADPCM encoding / decoding unit 121 side. I have.

【0016】また、LANインタフェース回路部120
はLAN構内交換機17からの状態問い合わせパケット
を所定時間毎に監視し、この状態問い合わせパケットを
受信しなかった場合にLAN1に障害が発生したと判断
し、その制御信号 によりリレー141の端子Aから
端子B側に切り換える(信号 はLAN構内交換機1
7からの状態問い合せパケットを定時間監視した結果を
示している)。したがって、LAN1に障害が発生した
場合と停電時には、通話インタフェース部142がAD
PCM符号化/復号化部121からPSTN31側に切
り換わるので、PSTN31を介して発信することがで
きる。さらに、LAN電話機10−2が単独で障害を監
視したりトラフィック量を測定したりして、障害があっ
たり極端にトラフィックが重い場合に切り換えるように
してもよい。この場合は、LAN電話機10−2内にそ
れぞれ監視手段を設けて、その出力によりリレー141
を切り換えるように構成する。
The LAN interface circuit section 120
Monitors the status inquiry packet from the LAN private branch exchange 17 at predetermined time intervals. If the status inquiry packet is not received, it is determined that a failure has occurred in the LAN 1, and a terminal A through terminal A of the relay 141 is determined by the control signal. Switch to B side (signal is LAN private branch exchange 1
7 shows the result of monitoring the status inquiry packet from the server 7 for a fixed period of time. Therefore, when a failure occurs in the LAN 1 or during a power failure, the communication interface unit 142
The switching from the PCM encoding / decoding unit 121 to the PSTN 31 side enables transmission via the PSTN 31. Furthermore, the LAN telephone 10-2 may monitor the failure or measure the traffic amount by itself, and may switch when there is a failure or the traffic is extremely heavy. In this case, a monitoring means is provided in each of the LAN telephones 10-2, and the relay 141
Is configured to be switched.

【0017】また、図2はバックアップ回線としてPS
TN31を用いるLAN電話機10−2について説明し
たが、バックアップ回線としてデジタル公衆通信網であ
るISDN30を用いるLAN電話機10−3の場合に
は、図2に示すPSTNインタフェース103及びPS
TN回線収容部130の代わりに、ISDN30の呼制
御及び通信制御を行うISDNインタフェース及びIS
DN回線収容部を設けることにより、ISDN30をバ
ックアップ回線として用いることができる。
FIG. 2 shows a PS as a backup line.
Although the LAN telephone 10-2 using the TN 31 has been described, in the case of the LAN telephone 10-3 using the ISDN 30 which is a digital public communication network as a backup line, the PSTN interface 103 and the PSTN shown in FIG.
An ISDN interface and an ISDN for performing call control and communication control of the ISDN 30 instead of the TN line accommodating unit 130
By providing the DN line accommodation unit, the ISDN 30 can be used as a backup line.

【0018】[0018]

【発明の効果】以上説明したように本発明によれば、公
衆電話網との呼制御及び通信制御を行う公衆電話網イン
タフェースを設けるとともに、LAN上の障害を検出し
た場合に通話路をLANから公衆電話網インタフェース
に切り換えるようにしたので、LANに障害が発生して
も外線通話が可能なLAN電話機を実現することができ
る。本発明はまた、公衆電話網との呼制御及び通信制御
を行う公衆電話網インタフェースを設けるとともに、商
用電源の停電時に通話路をLANから公衆電話網インタ
フェースに切り換えるようにしたので、商用電源が停電
しても外線通話が可能なLAN電話機を実現することが
できる。
As described above, according to the present invention, a public telephone network interface for performing call control and communication control with the public telephone network is provided, and when a failure on the LAN is detected, the communication path is switched from the LAN. By switching to the public telephone network interface, it is possible to realize a LAN telephone capable of making an external call even if a failure occurs in the LAN. The present invention also provides a public telephone network interface for performing call control and communication control with the public telephone network, and switches the communication path from the LAN to the public telephone network interface when the commercial power is interrupted. Thus, it is possible to realize a LAN telephone that can perform an outside line call.

【図面の簡単な説明】[Brief description of the drawings]

【図1】本発明に係るLAN電話機の一実施形態が適用
されたLAN(ローカルエリアネットワーク)構内交換
ネットワークを示すブロック図である。
FIG. 1 is a block diagram showing a LAN (Local Area Network) private branch exchange network to which an embodiment of a LAN telephone according to the present invention is applied.

【図2】図1のPSTN対応のLAN電話機を詳細に示
すブロック図である。
FIG. 2 is a block diagram showing a PSTN-compatible LAN telephone shown in FIG. 1 in detail.

【符号の説明】[Explanation of symbols]

10−1、10−2、10−3 LAN電話機 30 ISDN 31 PSTN 103 PSTNインタフェース 120 LANインタフェース回路部(障害検出手段) 122 電源部 130 PSTN回線収容部(PSTNインタフェース
103と共に公衆電話網インタフェースを構成する) 140 電源管理部(停電検出手段) 141 リレー(回線切り換え手段) 142 通話インタフェース部
10-1, 10-2, 10-3 LAN telephone 30 ISDN 31 PSTN 103 PSTN interface 120 LAN interface circuit section (failure detecting means) 122 Power supply section 130 PSTN line accommodating section (constitutes public telephone network interface with PSTN interface 103) 140 power supply management unit (power failure detection means) 141 relay (line switching means) 142 call interface unit

Claims (3)

【特許請求の範囲】[Claims] 【請求項1】 LAN上の障害を検出する障害検出手段
と、 公衆電話網との呼制御及び通信制御を行う公衆電話網イ
ンタフェースと、 前記障害検出手段が前記LAN上の障害を検出した場合
に通話路を前記LANから前記公衆電話網インタフェー
スに切り換える回線切り換え手段とを、 有するLAN電話機。
1. A failure detecting means for detecting a failure on a LAN, a public telephone network interface for performing call control and communication control with a public telephone network, and when the failure detecting means detects a failure on the LAN. Line switching means for switching a communication path from the LAN to the public telephone network interface.
【請求項2】 商用電源の停電を検出する停電検出手段
と、 公衆電話網との呼制御及び通信制御を行う公衆電話網イ
ンタフェースと、 前記停電検出手段が商用電源の停電を検出した場合に通
話路をLANから前記公衆電話網インタフェースに切り
換える回線切り換え手段とを、 有するLAN電話機。
2. A power failure detection means for detecting a power failure of a commercial power supply, a public telephone network interface for performing call control and communication control with a public telephone network, and a telephone call when the power failure detection means detects a commercial power failure. Line switching means for switching a route from a LAN to the public telephone network interface.
【請求項3】 LAN上の障害を検出する障害検出手段
と、 商用電源の停電を検出する停電検出手段と、 公衆電話網との呼制御及び通信制御を行う公衆電話網イ
ンタフェースと、 前記障害検出手段が前記LAN上の障害を検出した場
合、又は前記停電検出手段が商用電源の停電を検出した
場合に通話路を前記LANから前記公衆電話網インタフ
ェースに切り換える回線切り換え手段とを、 有するLAN電話機。
3. A failure detection means for detecting a failure on the LAN, a power failure detection means for detecting a power failure of a commercial power supply, a public telephone network interface for performing call control and communication control with a public telephone network, and the failure detection. A line switching means for switching a communication path from the LAN to the public telephone network interface when the means detects a failure on the LAN or when the power failure detection means detects a power failure of a commercial power supply.
JP9087500A 1997-03-21 1997-03-21 Lan telephone set Withdrawn JPH10271243A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP9087500A JPH10271243A (en) 1997-03-21 1997-03-21 Lan telephone set

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP9087500A JPH10271243A (en) 1997-03-21 1997-03-21 Lan telephone set

Publications (1)

Publication Number Publication Date
JPH10271243A true JPH10271243A (en) 1998-10-09

Family

ID=13916707

Family Applications (1)

Application Number Title Priority Date Filing Date
JP9087500A Withdrawn JPH10271243A (en) 1997-03-21 1997-03-21 Lan telephone set

Country Status (1)

Country Link
JP (1) JPH10271243A (en)

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JP2003509974A (en) * 1999-09-17 2003-03-11 インターテックス データ エービー Telecommunications systems and devices
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JP2006319699A (en) * 2005-05-13 2006-11-24 Nakayo Telecommun Inc Non-power failure packet telephone system
JP2008258841A (en) * 2007-04-03 2008-10-23 Nakayo Telecommun Inc Extension telephone with alternative outside line connection function
JP2021129280A (en) * 2020-02-17 2021-09-02 沖電気工業株式会社 Communication device, communication system, voice data relay method, and communication program
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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003509974A (en) * 1999-09-17 2003-03-11 インターテックス データ エービー Telecommunications systems and devices
US7804815B1 (en) 1999-09-17 2010-09-28 Intertex Data Ab System and apparatus for telecommunication
KR100373516B1 (en) * 2000-12-18 2003-02-25 엘지전자 주식회사 Home appliance connection circuit and control method thereof for exchange
JP2006180341A (en) * 2004-12-24 2006-07-06 Nec Engineering Ltd Ip-pbx system and terminal
JP2006319699A (en) * 2005-05-13 2006-11-24 Nakayo Telecommun Inc Non-power failure packet telephone system
JP4603417B2 (en) * 2005-05-13 2010-12-22 株式会社ナカヨ通信機 Packet telephone system for power failure
JP2008258841A (en) * 2007-04-03 2008-10-23 Nakayo Telecommun Inc Extension telephone with alternative outside line connection function
JP2021129280A (en) * 2020-02-17 2021-09-02 沖電気工業株式会社 Communication device, communication system, voice data relay method, and communication program
JP2022072955A (en) * 2020-10-30 2022-05-17 Necプラットフォームズ株式会社 Ip (internet protocol) phone, ip-pbx (private branch exchange), and ip-pbx system

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