JP2008072378A - Ip communication system - Google Patents

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JP2008072378A
JP2008072378A JP2006248583A JP2006248583A JP2008072378A JP 2008072378 A JP2008072378 A JP 2008072378A JP 2006248583 A JP2006248583 A JP 2006248583A JP 2006248583 A JP2006248583 A JP 2006248583A JP 2008072378 A JP2008072378 A JP 2008072378A
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pbx
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voice
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Kazunori Washizu
和則 鷲津
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NEC Engineering Ltd
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<P>PROBLEM TO BE SOLVED: To solve the problems that it is impossible to detect a silence and one-sided speech being abnormality of sound communication caused by a failure of an IP-PBX and an IP terminal and that illegal sound packets can not be stopped when an IP terminal that can not be controlled by the IP-PBX continuously transmits the illegal sound packets. <P>SOLUTION: A router analyzes a sound packet, and detects the sound packet as abnormality when a silence or one-sided speech continues for a long time that is longer than a threshold. The router notifies the IP-PBX of the abnormality, the IP-PBX sends an instruction to stop sound communication to the IP terminal, and the IP terminal stops transmitting the sound packet. When a transmitting source of an illegal sound packet is an IP terminal that is not controlled by the IP-PBX, the illegal sound packet is filtered by an IP address and a port number and discarded. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

本発明はＩＰ−ＰＢＸ（Ｉｎｔｅｒｎｅｔ Ｐｒｏｔｏｃｏｌ−Ｐｒｉｖａｔｅ Ｂｒａｎｃｈ Ｅｘｃｈａｎｇｅ）においてＩＰ（Ｉｎｔｅｒｎｅｔ Ｐｒｏｔｏｃｏｌ）端末間で送受信される音声データの異常を検出し、復旧するＩＰ通信システムに関する。   The present invention relates to an IP communication system that detects and recovers from an abnormality in voice data transmitted and received between IP (Internet Protocol) terminals in an IP-PBX (Internet Protocol-Private Branch Exchange).

図１０は、一般的なＩＰ通信システムを示す。このＩＰ通信システムは、ＩＰ−ＰＢＸ11に収容されたＩＰ端末12，13間の音声通信はＲＴＰ（Ｒｅａｌｔｉｍｅ Ｔｒａｎｓｐｏｒｔ Ｐｒｏｔｏｃｏｌ）等のプロトコルによりＩＰ−ＰＢＸ11を介さずにルータ22’，23’とローカルネットワーク32，33を経由して、 Ｐｅｅｒ ｔｏ Ｐｅｅｒで行われる。このため、ＩＰ−ＰＢＸ11ではＩＰ端末12，13間の音声通信の異常を検出することができない。   FIG. 10 shows a general IP communication system. In this IP communication system, voice communication between the IP terminals 12 and 13 accommodated in the IP-PBX 11 is performed by the routers 22 'and 23' and the local network 32 without using the IP-PBX 11 by a protocol such as RTP (Realtime Transport Protocol). , 33 via Peer to Peer. For this reason, the IP-PBX 11 cannot detect an abnormality in voice communication between the IP terminals 12 and 13.

これを解決するための従来技術として、ルータを介してネットワークと接続された測定装置において、ネットワークの障害（遅延，パケット損失，ゆらぎ等）を検出することで、コーデックの変更、新たな通信の規制、優先度の低い通信の切断を行い、ネットワークの負荷を軽減し、これによりネットワークの障害を起因とする音声通信の異常（遅延，音切れ，ひずみ）を防止する音声品質制御システム（例えば、特許文献１参照）が知られている。   As a conventional technique for solving this problem, a measuring device connected to a network via a router detects a network failure (delay, packet loss, fluctuation, etc.), thereby changing the codec and regulating new communications. A voice quality control system (for example, patents) that cuts off low-priority communications and reduces network load, thereby preventing voice communication anomalies (delays, interruptions in sound, distortion) caused by network failures Document 1) is known.

特開２００６−１２１１６６号公報（第６頁−第９頁、図１）Japanese Patent Laying-Open No. 2006-121166 (page 6 to page 9, FIG. 1)

しかしながら、上述した従来技術では、ネットワークの障害を起因とする音声通信の異常を検出することはできるが、ＩＰ−ＰＢＸおよびＩＰ端末の障害を起因とする音声通信の異常である無音や片通話を検出することができないという問題点がある。   However, although the above-described conventional technology can detect an abnormality in voice communication caused by a network failure, it can detect silence or one-way communication that is an abnormality in voice communication caused by an IP-PBX or IP terminal failure. There is a problem that it cannot be detected.

また、ＩＰ−ＰＢＸから制御できないＩＰ端末が不正な音声パケットを送出し続けている場合も、これを止めることができない。不正な音声パケットによりネットワークが輻輳すると、正常であった音声通信に異常を来たしてしまう。これによるコーデックの変更、新たな通信の規制、優先度の低い通信の切断はサービスの低下に他ならず、根本的な解決にはならない。   Further, even when an IP terminal that cannot be controlled from the IP-PBX continues to send out illegal voice packets, this cannot be stopped. When the network is congested by illegal voice packets, the normal voice communication is abnormal. Changing the codec, restricting new communication, and disconnecting low-priority communication is nothing but a fundamental problem.

そこで、本発明の目的は、ＩＰ−ＰＢＸまたはＩＰ端末の障害を起因とする音声通信の異常を検出し、音声通信の停止または音声パケットを破棄することで音声品質を維持するＩＰ通信システムを提供することにある。   SUMMARY OF THE INVENTION An object of the present invention is to provide an IP communication system that detects a voice communication abnormality caused by a failure of an IP-PBX or an IP terminal and maintains voice quality by stopping voice communication or discarding voice packets. There is to do.

本発明のＩＰ通信システムは、基幹ネットワーク（図１の40）とローカルネットワーク（図１の31〜33）の境界に配置されたルータ（図１の21〜23）に音声監視手段（図１の20-1）とフィルタ手段（図１の20-2）を付加する。音声監視手段は、ＩＰ端末（図１の12，13）の間においてＰｅｅｒ ｔｏ Ｐｅｅｒで行なわれる音声通信の音声パケットを分析し、無音や片通話が閾値以上の長時間継続した場合、異常として検出する。異常を検出した場合、ルータからＩＰ−ＰＢＸ（図１の11）に通知し、ＩＰ−ＰＢＸはＩＰ端末に音声通信を停止する指示を送り、ＩＰ端末は音声パケットの送出を停止する。また、不正な音声パケットの送出元がＩＰ−ＰＢＸの制御対象外のＩＰ端末である場合、フィルタ手段はＩＰアドレスとポート番号により不正な音声パケットをフィルタし破棄する。   The IP communication system according to the present invention has voice monitoring means (FIG. 1) connected to routers (21 to 23 in FIG. 1) arranged at the boundary between the backbone network (40 in FIG. 1) and the local network (31 to 33 in FIG. 1). 20-1) and filter means (20-2 in FIG. 1) are added. The voice monitoring means analyzes voice packets for voice communication performed peer-to-peer between IP terminals (12, 13 in FIG. 1), and detects silence or abnormal one-way conversations for a long time that exceeds a threshold. To do. When an abnormality is detected, the router notifies the IP-PBX (11 in FIG. 1), the IP-PBX sends an instruction to stop voice communication to the IP terminal, and the IP terminal stops sending voice packets. In addition, when the transmission source of the illegal voice packet is an IP terminal that is not controlled by the IP-PBX, the filter unit filters and discards the illegal voice packet based on the IP address and the port number.

本発明によれば、ルータに音声監視手段を設けたため、従来は検出できなかったＩＰ−ＰＢＸおよびＩＰ端末の障害を起因とする音声通信の異常を検出し、検出した異常をＩＰ−ＰＢＸに通知することで、ＩＰ−ＰＢＸから異常を復旧させることができるという第１の効果を得ることができる。   According to the present invention, since the router is provided with voice monitoring means, it detects an abnormality in voice communication caused by a failure of the IP-PBX and the IP terminal, which could not be detected conventionally, and notifies the detected abnormality to the IP-PBX. By doing so, the first effect that the abnormality can be recovered from the IP-PBX can be obtained.

また、ルータにフィルタ手段を設けたため、ＩＰ−ＰＢＸから異常を復旧できない場合は、ルータで不正な音声パケットを破棄することができ、これにより不正な音声パケットによるネットワークの輻輳を防止し、音声品質を維持することができるという第２の効果を得ることができる。   In addition, since the router is provided with filter means, if the IP-PBX cannot recover the abnormality, the router can discard the illegal voice packet, thereby preventing the network congestion due to the illegal voice packet, and the voice quality. The second effect that it can be maintained can be obtained.

本発明のＩＰ通信システムは、その一例を図１に示すように、ＩＰ−ＰＢＸ11がローカルネットワーク31とルータ21を経由して、またＩＰ端末12がローカルネットワーク32とルータ22、ＩＰ端末13がローカルネットワーク33とルータ23を経由して、それぞれ基幹ネットワーク40に接続されている。   In the IP communication system of the present invention, as shown in FIG. 1, an IP-PBX 11 is routed through a local network 31 and a router 21, an IP terminal 12 is a local network 32 and a router 22, and an IP terminal 13 is local. Each is connected to the backbone network 40 via the network 33 and the router 23.

ＩＰ−ＰＢＸ11は、ＩＰ端末12，13の音声通信を開始および停止させる音声通信制御部11-1を有する。ＩＰ端末12とＩＰ端末13はＰｅｅｒ ｔｏ Ｐｅｅｒで音声通信を行う機能を有する。ルータ21，22，23は、基幹ネットワーク40とそれぞれローカルネットワーク31，32，33の境界に配置され、音声パケットを分析する音声監視手段20-1と、特定のＩＰアドレスとポート番号の音声パケットをフィルタし破棄するフィルタ手段20-2を有する。   The IP-PBX 11 includes a voice communication control unit 11-1 that starts and stops voice communication of the IP terminals 12 and 13. The IP terminal 12 and the IP terminal 13 have a function of performing voice communication by Peer to Peer. The routers 21, 22, and 23 are arranged at the boundary between the backbone network 40 and the local networks 31, 32, and 33, respectively, and voice monitoring means 20-1 that analyzes voice packets, and voice packets having a specific IP address and port number. Filter means 20-2 for filtering and discarding.

ＩＰ端末12，13とルータ21，22，23とローカルネットワーク31，32，33のＩＰアドレスは図１中に書き入れてあるとおりとする。ＩＰ−ＰＢＸ11は、図２に示すように、制御しているＩＰ端末12，13のＩＰアドレスリストと、図３に示すように、音声通信を監視させるルータ21，22，23のＩＰアドレスリストを保持しており、ルータ22，23に対してＩＰ端末12，13のＩＰアドレスリストを配布する。   The IP addresses of the IP terminals 12, 13, the routers 21, 22, 23 and the local networks 31, 32, 33 are as written in FIG. As shown in FIG. 2, the IP-PBX 11 has an IP address list of IP terminals 12 and 13 under control and an IP address list of routers 21, 22, and 23 that monitor voice communication as shown in FIG. The IP address list of the IP terminals 12 and 13 is distributed to the routers 22 and 23.

ＩＰ端末12とＩＰ端末13がルータ22，23を経由して音声通信を行っている際、ルータ22，23の音声監視手段20-1は、送信元または送信先がＩＰアドレスリストにある音声パケットについて分析を行う。正常に通話している場合には、音声パケットに無音ではないデータが設定される。   When the IP terminal 12 and the IP terminal 13 are performing voice communication via the routers 22 and 23, the voice monitoring means 20-1 of the routers 22 and 23 is a voice packet whose source or destination is in the IP address list. Analyzes about In the case of a normal call, non-silent data is set in the voice packet.

終話の際に、ＩＰ−ＰＢＸ11またはＩＰ端末12，13の障害により復旧不良が生じ、図４に示すように、ＩＰ端末12，13から不正に無音の音声パケットが送出され続けたままになった場合、音声監視手段20-1は、無音を検出し閾値以上の長時間の無音が続いた場合、不正な音声パケットと判断する。   At the end of the call, a failure in recovery occurs due to a failure of the IP-PBX 11 or the IP terminals 12 and 13, and silent voice packets continue to be illegally transmitted from the IP terminals 12 and 13, as shown in FIG. In this case, the voice monitoring unit 20-1 determines that the voice packet is an illegal voice packet when silence is detected and silence for a long time equal to or greater than the threshold value continues.

不正な音声パケットを検出した場合、そのルータはＩＰ−ＰＢＸ11に不正な音声パケットの送出元のＩＰアドレスを通知する。通知を受けたＩＰ−ＰＢＸ11は送信元のＩＰアドレスに該当するＩＰ端末12，13に対して音声通信を停止する指示を送信し、指示を受けたＩＰ端末12，13は音声パケットの送出を停止する。ＩＰ−ＰＢＸ11からルータ22，23に対して復旧に成功したことを通知することで復旧は完了する。   When an illegal voice packet is detected, the router notifies the IP-PBX 11 of the IP address of the sender of the illegal voice packet. The IP-PBX 11 that has received the notification transmits an instruction to stop the voice communication to the IP terminals 12 and 13 corresponding to the IP address of the transmission source, and the IP terminals 12 and 13 that have received the instruction stop sending voice packets. To do. The restoration is completed when the IP-PBX 11 notifies the routers 22 and 23 that the restoration is successful.

一方、送信元のＩＰアドレスがＩＰ−ＰＢＸ11のＩＰアドレスリストにない場合、送信元のＩＰ端末12，13はＩＰ−ＰＢＸ11の制御対象外であるため、ＩＰ−ＰＢＸ11から音声通信を停止することはできず、図５に示すように、ＩＰ−ＰＢＸ11はルータ11に対して復旧できなかったことを通知する。通知を受けたルータ11のフィルタ手段20-2は、不正な音声パケットをＩＰアドレスとポート番号によりフィルタして破棄する。これにより基幹ネットワーク40への不正な音声パケットの流出を防止する。   On the other hand, when the source IP address is not in the IP address list of the IP-PBX 11, the source IP terminals 12 and 13 are outside the control target of the IP-PBX 11, so that the voice communication from the IP-PBX 11 is not stopped. As shown in FIG. 5, the IP-PBX 11 notifies the router 11 that it could not be restored. Upon receiving the notification, the filter unit 20-2 of the router 11 filters the invalid voice packet by the IP address and the port number and discards it. As a result, the outflow of illegal voice packets to the backbone network 40 is prevented.

通常の通話では、ＩＰ端末12，13間の音声パケットは双方向に送受信される。ルータ22，23では音声パケットの送信元と送信先を記録し、音声監視手段20-1は双方向の音声通信であることを監視する。図６〜図８に示すように、ＩＰ−ＰＢＸ11またはＩＰ端末12，13の障害により片通話となった場合、音声監視手段20-1は片通話を検出し、閾値以上の長時間の片通話が続いた場合、ＩＰ−ＰＢＸ11に音声パケットの送出元と送出先のＩＰアドレスを通知する。   In a normal call, voice packets between the IP terminals 12 and 13 are transmitted and received in both directions. The routers 22 and 23 record the transmission source and transmission destination of the voice packet, and the voice monitoring means 20-1 monitors that the voice communication is bidirectional. As shown in FIGS. 6 to 8, when a one-way call is made due to a failure of the IP-PBX 11 or the IP terminals 12 and 13, the voice monitoring means 20-1 detects the one-way call and makes a long-term one-way call exceeding a threshold value. Is continued, IP-PBX 11 is notified of the voice packet source and destination IP addresses.

ＩＰ−ＰＢＸ11には片方向の音声通信を行うサービスが一部存在するため、通知を受けたＩＰ−ＰＢＸ11は受信したＩＰアドレスに該当するＩＰ端末12，13のサービスの状態を確認し、片方向の音声通信を行うサービス中であれば、図６に示すように、正常な音声通信であることをルータ22，23に通知する。   Since the IP-PBX 11 has a part of service for performing one-way voice communication, the notified IP-PBX 11 confirms the service status of the IP terminals 12 and 13 corresponding to the received IP address, and the one-way If the service for performing the voice communication is in progress, the routers 22 and 23 are notified of the normal voice communication as shown in FIG.

一方、片方向の音声通信を行うサービス中でない場合、音声監視手段20-1が無音を検出した場合（図４，図５）と同様に、フィルタ手段20-2は、音声通信の停止（図７）またはルータにおける音声パケットの破棄（図８）を行う。   On the other hand, when the service for performing one-way voice communication is not being performed, the filter means 20-2 stops the voice communication (see FIG. 4 and FIG. 5) as in the case where the voice monitoring means 20-1 detects silence (FIGS. 4 and 5). 7) Or the voice packet is discarded in the router (FIG. 8).

また、図９に示すように、外部のネットワーク（インターネット34）から悪意を持った外部ＩＰ端末14が不正な音声パケットを送出し続けている場合も、同じ仕組みにより片通話として検出し、ルータ24で不正な音声パケットを破棄することができる。   Further, as shown in FIG. 9, when the malicious external IP terminal 14 continues to send out illegal voice packets from the external network (Internet 34), it is detected as a one-way call by the same mechanism, and the router 24 Can discard illegal voice packets.

本発明のＩＰ通信システムの一例を示す図The figure which shows an example of the IP communication system of this invention ＩＰ−ＰＢＸで制御しているＩＰ端末のＩＰアドレスリストを示す図The figure which shows the IP address list of the IP terminal currently controlled by IP-PBX 音声通信を監視するルータのＩＰアドレスリストを示す図The figure which shows the IP address list of the router which monitors voice communication 無音検出時のＩＰ−ＰＢＸによる復旧シーケンス図Recovery sequence diagram using IP-PBX when detecting silence 無音検出時のルータによるフィルタのシーケンス図Sequence diagram of filter by router when silence is detected 片通話検出時の片通話サービス中のシーケンス図Sequence diagram during single call service when single call is detected 片通話検出時のＩＰ−ＰＢＸによる復旧シーケンス図Recovery sequence diagram by IP-PBX when one call is detected 片通話検出時のルータによるフィルタのシーケンス図Filter sequence diagram by router when one-way call is detected 外部からの悪意な送信検出時のルータによるフィルタのシーケンス図Sequence diagram of filter by router when detecting malicious transmission from outside 一般的なＩＰ通信システムを示す図Diagram showing a general IP communication system

符号の説明Explanation of symbols

11 ＩＰ−ＰＢＸ
12，13 ＩＰ端末
21，22，23 ルータ
31、32、33 ローカルネットワーク
34 インターネット
40 基幹ネットワーク
11-1 音声制御部
20-1 音声監視手段
20-2 フィルタ手段
11 IP-PBX
12, 13 IP terminal
21, 22, 23 routers
31, 32, 33 Local network
34 Internet
40 Core network
11-1 Voice control unit
20-1 Voice monitoring means
20-2 Filter means

Claims (3)

ＩＰ−ＰＢＸおよびＩＰ端末がローカルネットワークとルータを経由して基幹ネットワークに接続されているＩＰ通信システムにおいて、
前記ＩＰ−ＰＢＸは、前記ＩＰ端末のＩＰアドレスリストと、前記ルータのＩＰアドレスリストを保持しており、Ｐｅｅｒ ｔｏ Ｐｅｅｒで音声通信を行うＩＰ端末対応のルータに対してＩＰ端末のＩＰアドレスリストを配布することと、
前記ルータは、送信元または送信先が前記ＩＰアドレスリストにある音声パケットについて分析を行い、無音や片通話が閾値以上の長時間継続した場合は不正な音声パケットと判断することと、
前記ＩＰ−ＰＢＸに前記不正な音声パケットの送出元のＩＰアドレスを通知することと、
前記不正な音声パケットの送出元のＩＰアドレスが前記ＩＰ−ＰＢＸのＩＰアドレスリストにないため、前記ＩＰ−ＰＢＸから復旧できなかったことの通知を受けると、前記不正な音声パケットをＩＰアドレスとポート番号によりフィルタして破棄することを特徴とするＩＰ通信システム。 In an IP communication system in which IP-PBX and IP terminal are connected to a backbone network via a local network and a router,
The IP-PBX holds an IP address list of the IP terminal and an IP address list of the router, and the IP address list of the IP terminal is provided to a router corresponding to the IP terminal that performs peer-to-peer voice communication. Distribution and
The router analyzes a voice packet whose source or destination is in the IP address list, and determines that it is an illegal voice packet if silence or one-way conversation continues for a long time exceeding a threshold;
Notifying the IP-PBX of the IP address of the sender of the unauthorized voice packet;
Upon receiving a notification that the IP-PBX could not be recovered because the IP address of the illegal voice packet is not in the IP address list of the IP-PBX, the IP address and port An IP communication system characterized by filtering by number and discarding. 前記無音の通知を受けたＩＰ−ＰＢＸは、前記送信元のＩＰアドレスに該当するＩＰ端末に対して音声通信を停止する指示を送信してルータに対して復旧に成功したことを通知することと、
前記指示を受けたＩＰ端末は当該音声パケットの送出を停止することを特徴とする請求項１記載のＩＰ通信システム。 The IP-PBX that has received the silence notification transmits an instruction to stop voice communication to the IP terminal corresponding to the IP address of the transmission source to notify the router that recovery has been successful. ,
The IP communication system according to claim 1, wherein the IP terminal that has received the instruction stops sending the voice packet. 前記片通話の通知を受けたＩＰ−ＰＢＸは、受信したＩＰアドレスに該当するＩＰ端末のサービスの状態を確認することと、
前記確認の結果により片方向の音声通信を行うサービス中であれば正常な音声通信であることを当該ルータに通知することと、
前記確認の結果により片方向の音声通信を行うサービス中でない場合は、前記送信元のＩＰアドレスに該当するＩＰ端末に対して音声通信を停止する指示を送信してルータに対して復旧に成功したことを通知することと、
前記指示を受けたＩＰ端末は当該音声パケットの送出を停止することを特徴とする請求項１記載のＩＰ通信システム。


The IP-PBX that has received the one-call notification confirms the service status of the IP terminal corresponding to the received IP address;
Notifying the router that the voice communication is normal if the result of the confirmation is a service that performs one-way voice communication;
If the result of the confirmation indicates that the service is not in a one-way voice communication, the router successfully recovered the router by sending an instruction to stop the voice communication to the IP terminal corresponding to the source IP address. To notify
The IP communication system according to claim 1, wherein the IP terminal that has received the instruction stops sending the voice packet.


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