JP2004228746A - Stream quality observation apparatus, program, and recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem that it is difficult to more circumstantially particularize a defective point in a network from information obtained by technologies drawn up into bylaws wherein a receiving apparatus side observes quality of stream communication and informs a transmission apparatus about the result in the quality observation of the stream communication. <P>SOLUTION: Provided is a stream quality observation apparatus located between the transmission apparatus and the receiving apparatus that is characterized in to include a function of storing in units of sessions a first quality value denoting the quality of a stream between the transmission apparatus and the receiving apparatus obtained from the result of observation and a second quality value denoting the quality of a stream between the transmission apparatus and the observation apparatus obtained from the result of observation and to calculate a third quality value denoting the quality of the stream between the observation apparatus and the receiving apparatus, which cannot directly be obtained from the observation, on the basis of the first and second quality values. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

ジッタ値Ｊ１は、タイムスタンプ１０３−３とＲＦＣ１８８９に記述されているアルゴリズムを使用して求める。
【００４０】
受信状況メッセージ解析部１４０は、受信状況メッセージについてのフォーマット情報を備えており、フォーマット情報に基づいて、受信パケットからパケットロス率Ｐ２、ジッタ値Ｊ２を取得し（＃４０６）、品質データ１０４の送信装置−受信装置間の品質値１０４−３のパケットロス率Ｐ２（１０４−７）及びジッタ値Ｊ２（１０４−８）に、前述のセションＩＤに対応付けて記録する（＃４０７）。
【００４１】
ストリーム品質解析部１２０は、品質データ１０４から、送信装置−観測装置間の品質値１０４−２のパケットロス率Ｐ１（１０４−５）及びジッタ値Ｊ１（１０４−６）と、送信装置−受信装置間の品質値１０４−３のパケットロス率Ｐ２（１０４−７）及びジッタ値Ｊ２（１０４−８）とを取得する。次にストリーム品質解析部１２０は、取得した送信装置−受信装置間の品質値１０４−３から、取得した送信装置−観測装置間の品質値１０４−２を減算することにより、受信装置−観測装置間の品質値１０４−４を生成し、パケットロス率Ｐ３（１０４−９）とジッタ値Ｊ３（１０４−１０）に記録する（＃４０８）。
【００４２】
観測装置‐受信装置間のジッタ値Ｊ３及びパケットロス率Ｐ３は、次式を用いて求める。
【００４３】
【数２】

【００４４】
【数３】

次にストリーム品質解析部１２０は、品質データ１０４に記録されている各品質値について、正常性の判定処理を行う（＃４０９）。この判定処理は、品質データ１０４に記録されている各品質値と規定値データ１０５，１０６とを比較することで行う。例えば、送信装置−観測装置間のジッタ値の判定処理は、品質データ１０４の送信装置−観測装置間のジッタ値Ｊ１（１０４−６）と、規定値データ（送信側）１０６のジッタ規定値１０６−３について、条件式［Ｊ１＞ジッタ規定値］を評価し、評価結果が真となる場合は、送信装置−観測装置間のジッタ値Ｊ１（１０４−６）は異常であると判定し、評価結果が偽となる場合は正常と判定する（＃４０９）。同様に、受信装置−観測装置間のジッタ値の判定処理は、品質データ１０４の受信装置−観測装置間のジッタ値Ｊ３（１０４−１０）と規定値データ（受信側）１０５のジッタ規定値１０５−３について、条件式［Ｊ３＞ジッタ規定値］を評価し、評価結果が真となる場合は、受信装置−観測装置間のジッタ値Ｊ３（１０４−１０）は異常であると判定し、評価結果が偽となる場合は正常と判定する（＃４０９）。パケットロス率についても同様に、各ネットワーク区間の品質値について、条件式［生成処理手段を用いて生成したパケットロス率＞パケットロス規定率］を評価し、評価結果が真となる場合は異常と判定し、評価結果が偽となる場合は正常と判定する（＃４０９）。
【００４５】
前述の規定値データ１０５及び規定値データ１０６は、観測装置１００を起動する前に設定されているものとし、ジッタ値及びパケットロス率と音声・映像ストリームの品質との関係を実験により調査して定めても良いし、又はプロバイダ事業者と利用者の間で交わされるサービス品質保証契約（ＳＬＡ）で定めた値を用いても良い。
【００４６】
次にストリーム品質解析部１２０は、前述のセションＩＤを用いてセション管理データベース１０２より得られる受信装置ＩＰアドレス１０２−２及び送信装置ＩＰアドレス１０２−３と、品質データ１０４に記録されているセションＩＤ１０４−１と、前述の判定結果とを用いて、表示データ１０７を作成し（＃４１０）、表示制御部１１０を実行する。
【００４７】
実行された表示制御部１１０は、ストリーム品質解析部１２０より通知された表示データ１０７を表示装置を介して表示する（＃４１１）。
【００４８】
本発明の実施例２におけるシステム構成を図３に示す。実施例２の観測装置１００は、送信装置２００と受信装置３００とを接続するネットワークＡ４００とネットワークＢ５００との間に接続され、ハブ６００のミラーリング機能を利用して、送信装置と受信装置間で送受信されるパケットのコピーを受信し、受信したパケットを観測する装置として機能する。
【００４９】
本実施例２は、実施例１の観測装置で行っていた中継処理に相当する処理をハブ６００で行うという点で実施例１と異なる以外は、実施例１と同じ構成となる。すなわち、ストリームデータ解析部１３０、受信状況メッセージ解析部１４０、ストリーム品質解析部１２０、表示制御部１１０については実施例１と同様となる。
【００５０】
また以上で説明した実施例は、ストリーム通信の品質の正常性を判定する基準として、各品質値の種別毎（ジッタ値、パケットロス率）に１つの規定値を設けた例を示したが、品質が正常である状態から異常への遷移の判定に用いる第一の規定値と、異常である状態から正常への遷移の判定に用いる第二の規定値との２つの規定値を設けても良い。この場合、第一の規定値と第二の規定値とは次の関係式を満たすものとする。
【００５１】
・第一の規定値 ≧ 第二の規定値
前記第一及び第二の規定値は、いずれか一方を設定することにより、他方の値を算出処理により導出しても良い。前記第一及び第二の規定値により、品質値が規定値近傍を推移する場合において、正常と異常とが短い間隔で交互に判定されることを避けることが可能となり、利用者の誤認を防ぐという効果を期待できる。
【００５２】
【発明の効果】
本発明により、インターネット上のストリーム配信やＶｏＩＰなどのシステムにおいてユーザの音声・ビデオのストリーム品質が低下した時に、原因が送信装置側のネットワークか受信装置側のネットワークか識別できるようになる。
【００５３】
以上の説明に関して更に以下の項を開示する。
【００５４】
（付記１）複数の異なるネットワークセグメントで構成されたネットワーク網を介して接続された送信装置と受信装置を含むストリーム通信システムにおいて、送信装置と受信装置との通信経路を構成するネットワークセグメントの間に接続され、送信装置と受信装置とを接続する通信経路におけるストリーム通信のネットワーク品質を観測する装置であって、
送信装置と受信装置とを接続する通信経路におけるストリーム通信のストリームデータを構成するパケットを受信する受信処理手段と、
前記受信処理手段を用いて受信した受信パケットに対してセション単位で一意となるセション識別子を割り振り、前記受信パケットとセション識別子を対応付けて管理するセション識別処理手段と、
前記受信パケットのパケット種別を識別するパケット種別識別処理手段と、
前記パケット種別識別処理手段により前記受信パケットが受信装置から送信装置へ送信された受信状況メッセージであると判定された場合は、前記受信パケットから受信パケット中に含まれる送信装置と受信装置とを接続する通信経路におけるストリームの品質値を生成する第一の品質値生成処理手段と、
前記受信パケット種別識別処理手段により前記受信パケットが送信装置から受信装置へ送信されたストリームデータであると判定された場合は、前記受信パケットから得られる情報をもとに送信装置と観測装置とを接続する通信経路におけるストリーム通信の品質値を生成する第二の品質値生成処理手段と、
同一のセション識別子で対応付けされた前記第一及び第二の品質値生成処理手段を用いて生成した品質値から、観測装置と受信装置とを接続する通信経路におけるストリーム通信の品質値を生成する第三の品質値生成処理手段と、
を備えることを特徴とするストリーム品質観測装置。
【００５５】
（付記２）送信装置と観測装置間及び観測装置と受信装置間におけるストリーム通信の品質値と、品質の判断基準とする目的であらかじめ設定された規定値と、を比較することによりストリーム通信の品質の正常性を判定する品質判定処理手段と、
を備えることを特徴とする付記１に記載のストリーム品質観測装置。
【００５６】
（付記３）前記品質判定処理手段により判定された送信装置と観測装置間及び受信装置と観測装置間におけるストリーム通信の品質の結果をセション単位に表示する表示処理手段と、
を備えることを特徴とする付記２に記載のストリーム品質観測装置。
【００５７】
（付記４）複数の異なるネットワークセグメントで構成されたネットワーク網を介して接続された送信装置と受信装置を含むストリーム通信システムにおいて、送信装置と受信装置とを接続する通信経路を構成するネットワークセグメントの間に接続され、送信装置と受信装置とを接続する通信経路におけるストリーム通信のネットワーク品質を観測する装置としてコンピュータを機能させるプログラムであって、
送信装置と受信装置とを接続する通信経路におけるストリーム通信のストリームデータを構成するパケットを受信する処理と、
前記受信処理で受信した受信パケットに対してセション単位で一意となるセション識別子を割り振り、前記受信パケットとセション識別子を対応付けて管理する処理と、
前記受信パケットのパケット種別を識別する処理と、
前記パケット種別識別処理により前記受信パケットが受信装置から送信装置へ送信された受信状況メッセージであると判定された場合は、前記受信パケットから得られる情報をもとに送信装置と受信装置とを接続する通信経路におけるストリーム通信の品質値を生成する第一の品質値生成処理と、
前記受信パケット種別識別処理により前記受信パケットが送信装置から受信装置へ送信されたストリームデータであると判定された場合は、前記受信パケットから得られる情報をもとに送信装置と観測装置とを接続する通信経路におけるストリーム通信の品質値を生成する第二の品質値生成処理と、
同一のセション識別子で対応付けされた前記第一及び第二の品質値生成処理で生成した品質値から、観測装置と受信装置とを接続する通信経路におけるストリーム通信の品質値を生成する第三の品質値生成処理と、
をコンピュータに行わせることを特徴とするプログラム。
【００５８】
（付記５）送信装置と観測装置間及び観測装置と受信装置間におけるストリーム通信の品質値と、品質の判断基準とする目的であらかじめ設定された規定値と、を比較することによりストリーム通信の品質の正常性を判定する品質判定処理、
をコンピュータに行わせることを特徴とする付記４に記載のプログラム。
【００５９】
（付記６） 前記品質判定処理により判定された送信装置と観測装置間及び観測装置と受信装置間におけるストリーム通信の品質の結果をセション単位に表示する処理、
をコンピュータに行わせることを特徴とする付記５に記載のプログラム。
【００６０】
（付記７）複数の異なるネットワークセグメントで構成されたネットワーク網を介して接続された送信装置と受信装置を含むストリーム通信システムにおいて、送信装置と受信装置とを接続する通信経路を構成するネットワークセグメントの間に接続され、送信装置と受信装置とを接続する通信経路におけるストリーム通信のネットワーク品質を観測する装置としてコンピュータを機能させるプログラムを記録したコンピュータ可読の記録媒体であって、
送信装置と受信装置とを接続する通信経路におけるストリーム通信のストリームデータを構成するパケットを受信する処理と
前記受信処理で受信した受信パケットに対してセション単位で一意となるセション識別子を割り振り、前記受信パケットとセション識別子を対応付けて管理する処理と、
前記受信パケットのパケット種別を識別する処理と、
前記パケット種別識別処理により前記受信パケットが受信装置から送信装置へ送信された受信状況メッセージであると判定された場合は、前記受信パケットから受信パケット中に含まれる送信装置と受信装置とを接続する通信経路におけるストリーム通信の品質値を生成する第一の品質値生成処理と、
前記受信パケット種別識別処理により前記受信パケットが送信装置から受信装置へ送信されたストリームデータであると判定された場合は、前記受信パケットから得られる情報をもとに送信装置と観測装置とを接続する通信経路におけるストリーム通信の品質値を生成する第二の品質値生成処理と、
同一のセション識別子で対応付けされた前記第一及び第二の品質値生成処理で生成した品質値から、観測装置と受信装置とを接続する通信経路におけるストリーム通信の品質値を生成する第三の品質値生成処理と、
をコンピュータに行わせることを特徴とするプログラムを記録したコンピュータ可読の記録媒体。
【００６１】
（付記８）送信装置と観測装置間及び観測装置と受信装置間におけるストリーム通信の品質値と、品質の判断基準とする目的であらかじめ設定された規定値と、を比較することによりストリーム通信の品質の正常性を判定する品質判定処理、
をコンピュータに行わせることを特徴とする付記７に記載のプログラムを記録したコンピュータ可読の記録媒体。
【００６２】
（付記９） 前記品質判定処理により判定された送信装置と観測装置間及び観測装置と受信装置間におけるストリーム通信の品質の結果をセション単位に表示する処理、
をコンピュータに行わせることを特徴とする付記８に記載のプログラムを記録したコンピュータ可読の記録媒体。
【図面の簡単な説明】
【図１】観測装置の構成を示す図
【図２】実施例１のシステム構成を示す図
【図３】実施例２のシステム構成を示す図
【図４】パケット受信時の処理の内容を示すフローチャート図
【図５】実施例１のセション管理データベースの内容を示す図
【図６】受信パケットリストの内容を示す図
【図７】品質データの内容を示す図
【図８】規定値データ（受信側）の内容を示す図
【図９】規定値データ（送信側）の内容を示す図
【図１０】表示データの内容を示す図
【図１１】実施例２のセション管理データベースの内容を示す図
【図１２】ＲＴＰのデータ形式（ストリームデータ）を示す図[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a technique for specifying a network location that causes a decrease in stream quality of audio / video in a system such as stream distribution on the Internet or VoIP.
[0002]
[Prior art]
2. Description of the Related Art In recent years, as networks have become broadband, audio and video stream distribution services and Internet telephone services have become widespread. A communication path connecting a provider of such a service (hereinafter, referred to as a service provider) and a user thereof is often a network composed of a plurality of network segments as shown in FIG. . The network segment referred to here may be a broadcast domain that is a network range that can be reached by a broadcast request, which is a unit constituting a LAN, or may be a WAN that constitutes an organization intranet. Range. The transmission device shown in FIG. 2 corresponds to a service provider, and the reception device corresponds to a user. The above-described network composed of a plurality of network segments corresponds to the network composed of the network A400 and the network B500 shown in FIG. In such a connection form, when an event such as interruption of audio or video delivered in stream communication occurs, it is necessary to specify a location that causes a decrease in network quality of the stream communication. . In particular, the service provider needs to identify whether the problematic location is within the network under its own control or within the network under the control of an external communication carrier, and take immediate action.
[0003]
As a conventional technique for identifying a problem part from observation results of network service quality, network service quality (bit error rate, packet loss rate, data jitter, delay variation, etc.) is observed, and the network quality is inferior to the standard. Then, there is a communication controller having a function of switching to another route (see Patent Document 1). The route switching here is assumed to be performed automatically by observing the service quality of each route, specifying the location where the network quality has deteriorated.
[0004]
It can also collect quality of service, cell discards, cell loss and other network quality values from multiple network elements to detect that the quality of service is degraded for a particular node or link. There is a data monitoring device that can be used (see Patent Document 2).
[0005]
Further, as a conventional technique for observing the service quality of a network, a ping command is periodically issued from a transmitting apparatus to a receiving apparatus in order to obtain packet loss / jitter between a transmitting apparatus and a receiving apparatus, and whether or not a ping response is received. A technique of obtaining a packet loss rate or a jitter value representing network quality based on the response time or the time until a response is widely used.
[0006]
[Patent Document 1]
JP-A-11-27327
[0007]
[Patent Document 2]
JP-A-10-233773
[0008]
[Problems to be solved by the invention]
In the conventional methods disclosed in Patent Documents 1 and 2 described above, all packets flowing on the network are to be observed, and packets other than stream communication may be included in the observation target. There is a problem that the relationship with the network quality is unclear. That is, when the packet loss rate, which is one of the values representing the network quality, is obtained for all packets flowing on the network as observation targets, the packet loss rate may be a value including the loss of packets other than stream communication. There is. However, since the ratio of the stream communication packets to the lost packets cannot be specified, the actual network quality of the stream communication cannot be determined from the packet loss rate obtained for all the packets.
[0009]
As a technique for solving this problem, a technique for observing a packet loss rate and a jitter value representing the network quality of stream communication at a receiving apparatus performing stream communication and notifying the transmitting apparatus performing stream communication is defined as a protocol.
[0010]
However, from the network quality of the stream communication obtained from this, when the network connecting the transmitting device and the receiving device is composed of a plurality of network segments, the communication network connecting the transmitting device and the receiving device is not considered. It is not possible to obtain the quality of the subdivided section. For this reason, service providers that distribute audio and video streams should determine whether the cause of the degradation in stream communication quality is within their own network or a network under the control of an external telecommunications carrier. It has become difficult to identify.
[0011]
As described above, there is a problem in that it is not possible to obtain the quality of a section in which the communication path is further subdivided from an observation value in which the communication path from the transmitting apparatus to the receiving apparatus is the target section. As a known means for solving this problem, there is a method of providing an observation point on a communication path from a transmitting device to a receiving device. For example, as shown in FIG. 2, when an observation device is connected between a network A400 and a network B500, which are communication paths connecting the transmission device and the reception device, the transmission device transmits to the reception device (hereinafter, referred to as a downlink direction). ) By observing the transmitted packet using the observation device, it is possible to obtain downlink network quality between the transmission device and the observation device. Similarly, by observing a packet transmitted from the receiving device to the transmitting device (hereinafter, referred to as an up direction) using the observing device, obtaining the network quality in the up direction between the receiving device and the observing device. Can be done.
[0012]
This makes it possible to obtain the quality of a section in which the communication path from the transmitting device to the receiving device is further subdivided. However, the quality values of the network A400 and the network B500 obtained by the above-described observation are determined by the line to be observed. Direction is different. In other words, stream data that constitutes audio and video distributed by stream communication is sent from the transmitting device to the receiving device using the downlink line, but the above method can observe the downlink direction in all observation sections. Therefore, it does not mean that the stream data constituting the audio and video distributed by the stream communication is actually observed. For this reason, for example, when a line having a different band between the upstream and downstream, such as ADSL, is used, there is a possibility that the network quality value differs between the upstream and downstream lines. The problem is that accurate network quality cannot be observed for
[0013]
Therefore, the present invention has subdivided a communication path connecting a transmitting device and a receiving device in a stream communication system including a transmitting device and a receiving device connected via a network composed of a plurality of different network segments. Regarding the section as the observation target, regardless of whether the communication path connecting the transmitting device and the receiving device has an asymmetrical or symmetrical line bandwidth in the upstream and downstream directions, the normality of the network quality of the stream communication is checked. The purpose is to enable judgment.
[0014]
[Means for Solving the Problems]
In a stream communication system including a transmitting device and a receiving device connected via a network constituted by a plurality of different network segments, the streaming system is connected between network segments forming a communication path connecting the transmitting device and the receiving device. , A device for observing network quality of stream communication in a communication path connecting a transmitting device and a receiving device, and receiving a packet constituting stream data of the stream communication in a communication route connecting the transmitting device and the receiving device. Processing means, a session identification processing means for allocating a unique session identifier for each session to a reception packet received by using the reception processing means, and managing the reception packet in association with the session identifier; and Packet that identifies the packet type A type identification processing unit, and a transmission device included in the reception packet from the reception packet when the packet type identification processing unit determines that the reception packet is a reception status message transmitted from the reception device to the transmission device. Quality value generation processing means for generating a quality value of a stream in a communication path connecting the communication device and the reception device; and stream data in which the reception packet is transmitted from the transmission device to the reception device by the reception packet type identification processing means. If it is determined that, the second quality value generation processing means for generating a stream communication quality value in the communication path connecting the transmitting device and the observation device based on information obtained from the received packet, Quality values generated using the first and second quality value generation processing means associated with the same session identifier Et al., Characterized in that it comprises a third quality value generating means for generating a quality value of the stream communication in the communication path connecting the observation device and a receiving device. Note that the stream quality value defined here is, for example, a jitter value or a packet loss rate.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
The embodiment will be described using a stream communication system using RTSP (Real Time Streaming Protocol; RFC2326) as a control protocol and RTP (Real-time Transport Protocol; RFC1889) as a stream data protocol. Note that H.264 is used as a control protocol. Other protocols such as H.323 and SIP (Session Initiation Protocol) may be used, and a protocol such as RDT (Real Data Transport; RealNetworks) may be used as a stream data protocol.
[0016]
FIG. 2 shows a system configuration according to the first embodiment of the present invention. The observation device 100 according to the first embodiment is connected between a network A400 and a network B500 that connect the transmission device 200 and the reception device 300, and includes an RTCP (RTP) including a control protocol RTSP, stream data RTP, and a reception status message. Control Protocol). As the relay device, an RTSP proxy exists as a publicly known device, and thus detailed description of the operation as the relay device will be omitted.
[0017]
FIG. 1 shows the internal configuration of the stream quality observation device 100. The stream quality observation device 100 includes a communication control unit 150, a stream data analysis unit 130, a reception status message analysis unit 140, a stream quality analysis unit 120, a display control unit 110, and a stream management database 101.
[0018]
The stream management database 101 includes four types of databases: a session management database 102, a received packet list 103 of each session, quality data 104, and prescribed value data 105 and 106.
[0019]
The communication control unit 150 manages connections between the transmission device and the observation device and between the observation device and the reception device, and realizes a function as an RTSP proxy that relays data exchanged between the transmission device and the reception device. No relay processing means. Further, the communication control unit 150 sorts data for each session between the transmitting device and the receiving device based on the session management database 102, and sorts a received packet into stream data and a reception status message according to a packet type. And a packet type identification unit 152 that performs The relay processing means is realized by a processing procedure similar to that of a known RTSP proxy.
[0020]
The stream data analysis unit 130 analyzes the format of the stream data, and records the sequence number, the time stamp, and the reception time obtained from the stream data in the reception packet list 103. Further, the stream data analysis unit 130 includes a process of generating a jitter value J1 and a packet loss rate P1 from the received packets observed by the stream quality observation device 100 based on the values recorded in the received packet list 103, and converts the obtained values into quality values. Record in the data 104.
[0021]
The reception status message analysis unit 140 analyzes the format of the reception status message, and obtains the packet loss rate P2 and the jitter value J2 observed by the receiving device included in the reception status message. Further, the reception status message analysis unit records the acquired quality value and the session ID acquired by the communication control unit 150 in association with each other so that the session ID is unique in the quality management data 104.
[0022]
The stream quality analysis unit 120 calculates the jitter value J3 between the observation device and the reception device and the packet loss rate P3 from the current values of J1, J2, P1, and P2 registered in the quality data 104, and the cause of the quality deterioration. Including processing for detecting a location.
[0023]
The display control unit 110 displays the contents of the display data 107 including the session ID 107-1, the receiving device IP address 107-2, the transmitting device IP address 107-3, and the warning display 107-4 via the display device. .
[0024]
Next, various stored data will be described with reference to FIGS.
[0025]
The session management database shown in FIG. 5 includes a session ID 102-1, a receiving device IP address 102-2, a transmitting device IP address 102-3, and a receiving status message receiving port 102-4.
[0026]
The reception packet list shown in FIG. 6 includes a reception time 103-1, a sequence number 103-2, and a time stamp 103-3.
[0027]
The quality data shown in FIG. 7 includes the session ID 104-1, the packet loss rate (P1) 104-5 and the jitter value (J1) 104-6 between the transmitting device and the relay device, and the packet loss rate ( P2) 104-7 and a jitter value (J2) 104-8, a packet loss rate (P3) 104-9 between the receiving device and the observation device, and a jitter value (J3) 104-10.
[0028]
The specified value data shown in FIGS. 8 and 9 include the receiving (transmitting) device IP address 105-1 (106-1), the specified packet loss value 105-2 (106-2), and the specified jitter value 105-3 (106-). 3).
[0029]
The display data shown in FIG. 10 includes a session ID 107-1, a receiving device IP address 107-2, a transmitting device IP address 107-3, and a warning display 107-4.
[0030]
Next, the flow of processing at the time of packet reception will be described using the flowchart shown in FIG.
[0031]
First, the observation device 100 receives a packet of stream data transmitted from the transmission device 200 performing stream communication to the reception device 300 via the network A400 (# 401), and the communication control unit 150 is executed. The executed communication control unit 150 performs a session identification process on the received packet by using the session identification processing unit 151 (# 402). In the session identification process # 402, the IP address of the receiving device, the IP address of the transmitting device, and the receiving port number are obtained from the received packet, and the obtained value is compared with the data recorded in the session management database 102. As a result, a session ID 102-1 for uniquely identifying the session is obtained (# 402).
[0032]
The contents of the session management database 102 used here are determined before the above-described session identification process # 402 is executed using the information obtained from the packet of the RTSP SETUP response message transmitted from the transmitting device performing the stream communication. Created. The above-described RTSP SETUP response message is an RTSP packet transmitted from the transmitting device to the receiving device as a response to the RTSP SETUP request transmitted from the receiving device performing the stream communication to the transmitting device. The message describes port numbers of stream data (hereinafter, sometimes referred to as RTP) and a reception status message (hereinafter, sometimes referred to as RTCP) used by the receiving device. The communication control unit 150 obtains the IP addresses of the transmission device and the reception device, the stream data, and the port number of the reception status message from the response message described above, and stores the obtained values in the IP address 102-2 of the reception device and the IP address of the transmission device. The address 102-3, the stream data reception port 102-4, and the reception status message reception port 102-5 are recorded in association with each other so that each combination of values is unique. Further, the communication control unit 150 records an arbitrary value for uniquely identifying the above-described combination of values in the session management database in the session ID 102-1 in association with the combination of the above-described values, so that the session management database 102 Create
[0033]
Next, the communication control unit 150 uses the packet type identification processing unit 152 to identify the packet type of the received packet, and executes an analysis process according to the type (# 403).
[0034]
The executed packet type identification processing unit 152 acquires the IP addresses and the receiving port numbers of the receiving device and the transmitting device from the received packet, and sets the session information group associated with the combination of the acquired IP addresses of the receiving device and the transmitting device. From the session management database. The above-described session information corresponds to one record recorded in the session management database, and includes a session ID, IP addresses of a receiving device and a transmitting device, a stream data receiving port, and a receiving status message receiving port. Next, the packet type identification processing unit 152 checks the port number acquired from the received packet against the stream data of the acquired session information group and the reception port of the reception status message. The type is determined as stream data, and if it matches the reception status message reception port, the type of the received packet is determined as a reception status message.
[0035]
In the above-described identification processing, the received packet whose packet type is determined to be stream data is transmitted to the stream data analysis unit 130 (# 403-1). On the other hand, the received packet whose packet type is determined to be the reception status message is transmitted to the reception status message analysis unit 140 (# 403-2).
[0036]
The stream data analysis unit 130 includes format information of stream data, and acquires a sequence number and a time stamp (time of the transmitting device when the packet was transmitted from the transmitting device) from the received packet based on the format information. The time of the observation device at the time of execution of the acquisition process (hereinafter, referred to as reception time) is acquired from the system time, and the acquired values are received time 103-1, sequence number 103-2, and time stamp of the reception packet list 103. Record in 103-3. For example, as shown in FIG. 12, the format information 700 of the RTP is such that the third and fourth bytes of the data have a sequence number 701, the fifth and eighth bytes have a time stamp 702, and the third and fourth bytes of the received packet have the same format. From the fifth and eighth bytes, the sequence number and the time stamp can be obtained.
[0037]
Next, the stream data analysis unit 130 obtains the packet loss rate P1 and the jitter value J1 from the values recorded in the received packet list 103, and obtains the packet loss rate P1 (104-5) and the jitter value J1 (104-104) of the quality data 104. 6) (# 405). The above-described processing is repeatedly executed at predetermined time intervals set in advance.
[0038]
The method of calculating the packet loss rate P1 refers to the number R of received packets and the sequence number 103-2 of the received packets in the received packet list 103, and counts the number of skips S. The number of times S is defined as the number of packet losses, and the packet loss rate P1 is obtained by the following equation.
[0039]
(Equation 1)

The jitter value J1 is obtained by using an algorithm described in the time stamp 103-3 and RFC1889.
[0040]
The reception status message analyzer 140 has format information on the reception status message, acquires the packet loss rate P2 and the jitter value J2 from the received packet based on the format information (# 406), and transmits the quality data 104. The packet loss rate P2 (104-7) and the jitter value J2 (104-8) of the quality value 104-3 between the device and the receiving device are recorded in association with the above-mentioned session ID (# 407).
[0041]
From the quality data 104, the stream quality analysis unit 120 calculates the packet loss rate P1 (104-5) and the jitter value J1 (104-6) of the quality value 104-2 between the transmission device and the observation device, and the transmission device and the reception device. The packet loss rate P2 (104-7) and the jitter value J2 (104-8) of the interim quality value 104-3 are acquired. Next, the stream quality analysis unit 120 subtracts the acquired transmission device-observation device quality value 104-2 from the acquired transmission device-reception device quality value 104-3, thereby obtaining the reception device-observation device. A quality value 104-4 is generated and recorded in the packet loss rate P3 (104-9) and the jitter value J3 (104-10) (# 408).
[0042]
The jitter value J3 and the packet loss rate P3 between the observation device and the reception device are obtained using the following equations.
[0043]
(Equation 2)

[0044]
[Equation 3]

Next, the stream quality analysis unit 120 performs normality determination processing on each quality value recorded in the quality data 104 (# 409). This determination process is performed by comparing each quality value recorded in the quality data 104 with the specified value data 105 and 106. For example, the determination process of the jitter value between the transmission device and the observation device includes the jitter value J1 (104-6) between the transmission device and the observation device of the quality data 104 and the jitter specification value 106 of the specification value data (transmission side) 106. -3, the conditional expression [J1> specified jitter value] is evaluated. If the evaluation result is true, the jitter value J1 (104-6) between the transmitting device and the observation device is determined to be abnormal, and the evaluation is performed. If the result is false, it is determined to be normal (# 409). Similarly, the determination process of the jitter value between the receiving device and the observation device is performed by determining the jitter value J3 (104-10) between the receiving device and the observation device of the quality data 104 and the jitter specified value 105 of the specified value data (receiving side) 105. -3, the conditional expression [J3> specified jitter value] is evaluated. If the evaluation result is true, the jitter value J3 (104-10) between the receiving device and the observation device is determined to be abnormal, and the evaluation is performed. If the result is false, it is determined to be normal (# 409). Similarly, regarding the packet loss rate, the conditional expression [the packet loss rate generated by using the generation processing unit> the packet loss specified rate] is evaluated for the quality value of each network section, and if the evaluation result is true, it is determined to be abnormal. It is determined, and when the evaluation result is false, it is determined to be normal (# 409).
[0045]
It is assumed that the above-mentioned specified value data 105 and specified value data 106 are set before the observation device 100 is started, and the relationship between the jitter value and the packet loss rate and the quality of the audio / video stream is experimentally investigated. It may be determined, or a value determined by a service quality assurance contract (SLA) between the provider and the user may be used.
[0046]
Next, the stream quality analyzer 120 receives the receiver IP address 102-2 and the transmitter IP address 102-3 obtained from the session management database 102 using the above-described session ID, and the session ID 104 recorded in the quality data 104. The display data 107 is created using # 1 and the above-described determination result (# 410), and the display control unit 110 is executed.
[0047]
The executed display control unit 110 displays the display data 107 notified from the stream quality analysis unit 120 via the display device (# 411).
[0048]
FIG. 3 shows a system configuration according to the second embodiment of the present invention. The observation device 100 according to the second embodiment is connected between a network A400 and a network B500 that connect the transmission device 200 and the reception device 300, and transmits and receives between the transmission device and the reception device using the mirroring function of the hub 600. Function as a device that receives a copy of the received packet and observes the received packet.
[0049]
The second embodiment has the same configuration as the first embodiment except that the hub 600 performs processing corresponding to the relay processing performed by the observation device of the first embodiment. That is, the stream data analysis unit 130, the reception status message analysis unit 140, the stream quality analysis unit 120, and the display control unit 110 are the same as in the first embodiment.
[0050]
Further, in the embodiment described above, an example in which one specified value is provided for each type of quality value (jitter value, packet loss rate) as a criterion for determining the normality of the quality of stream communication, Even if two specified values are provided, a first specified value used to determine the transition from a state where the quality is normal to abnormal and a second specified value used to determine the transition from the abnormal state to normal. good. In this case, the first specified value and the second specified value satisfy the following relational expression.
[0051]
・ First specified value ≧ Second specified value
The first and second specified values may be set by setting one of them, and the other value may be derived by a calculation process. According to the first and second specified values, when the quality value changes in the vicinity of the specified value, it is possible to avoid that the normal and the abnormal are alternately determined at short intervals, thereby preventing the user from being erroneously recognized. The effect can be expected.
[0052]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, when the stream quality of a user's audio / video is reduced in a system such as stream distribution on the Internet or VoIP, the cause can be identified as the network on the transmitting device side or the network on the receiving device side.
[0053]
With respect to the above description, the following items are further disclosed.
[0054]
(Supplementary Note 1) In a stream communication system including a transmitting device and a receiving device connected via a network constituted by a plurality of different network segments, between a network segment forming a communication path between the transmitting device and the receiving device. A device for observing network quality of stream communication in a communication path connecting a transmitting device and a receiving device,
Receiving processing means for receiving a packet constituting stream data of stream communication in a communication path connecting the transmitting device and the receiving device;
A session identification processing unit that allocates a unique session identifier for each session to a reception packet received using the reception processing unit, and manages the reception packet in association with the session identifier.
Packet type identification processing means for identifying a packet type of the received packet;
When the packet type identification processing means determines that the received packet is a reception status message transmitted from the receiving device to the transmitting device, the transmitting device and the receiving device included in the received packet are connected from the received packet. First quality value generation processing means for generating a stream quality value in the communication path to be performed,
When the received packet type identification processing means determines that the received packet is stream data transmitted from the transmitting device to the receiving device, the transmitting device and the observing device are determined based on information obtained from the received packet. Second quality value generation processing means for generating a stream communication quality value in a communication path to be connected,
From the quality values generated using the first and second quality value generation processing means associated with the same session identifier, a quality value of stream communication in a communication path connecting the observation device and the reception device is generated. Third quality value generation processing means,
A stream quality observing device comprising:
[0055]
(Supplementary Note 2) The quality of the stream communication is compared by comparing the quality value of the stream communication between the transmitting device and the observing device and between the observing device and the receiving device with a predetermined value set for the purpose of determining the quality. Quality determination processing means for determining the normality of
2. The stream quality observation device according to claim 1, further comprising:
[0056]
(Supplementary Note 3) Display processing means for displaying the result of the quality of the stream communication between the transmitting device and the observing device and between the receiving device and the observing device determined by the quality determining processing means in session units,
3. The stream quality observation device according to supplementary note 2, comprising:
[0057]
(Supplementary Note 4) In a stream communication system including a transmitting device and a receiving device connected via a network configured by a plurality of different network segments, a stream segment that configures a communication path connecting the transmitting device and the receiving device. A program that causes a computer to function as a device that observes network quality of stream communication in a communication path that connects a transmitting device and a receiving device,
A process of receiving a packet constituting stream data of stream communication in a communication path connecting the transmitting device and the receiving device;
A process of allocating a unique session identifier for each session to the received packet received in the receiving process, and managing the received packet and the session identifier in association with each other;
A process of identifying a packet type of the received packet;
If it is determined by the packet type identification processing that the received packet is a reception status message transmitted from the receiving device to the transmitting device, the transmitting device and the receiving device are connected based on information obtained from the received packet. A first quality value generation process of generating a quality value of stream communication in a communication path to be performed,
When it is determined by the received packet type identification processing that the received packet is stream data transmitted from the transmitting device to the receiving device, the transmitting device and the observation device are connected based on information obtained from the received packet. Second quality value generation processing for generating a stream communication quality value in the communication path to be performed,
From the quality values generated in the first and second quality value generation processes associated with the same session identifier, a third value for generating a stream communication quality value in a communication path connecting the observation device and the reception device. Quality value generation processing,
A program that causes a computer to perform the following.
[0058]
(Supplementary Note 5) The quality of the stream communication is compared by comparing the quality value of the stream communication between the transmitting device and the observing device and between the observing device and the receiving device with a predetermined value set for the purpose of determining the quality. Quality judgment processing for judging the normality of
4. The program according to claim 4, wherein the program causes a computer to execute the program.
[0059]
(Supplementary Note 6) A process of displaying the results of the quality of the stream communication between the transmission device and the observation device and between the observation device and the reception device determined in the quality determination process in session units,
6. The program according to supplementary note 5, wherein the program causes the computer to execute the following.
[0060]
(Supplementary Note 7) In a stream communication system including a transmitting device and a receiving device connected via a network configured by a plurality of different network segments, a stream segment that forms a communication path connecting the transmitting device and the receiving device. A computer-readable recording medium recorded with a program for causing a computer to function as a device for observing network quality of stream communication in a communication path connecting a transmitting device and a receiving device,
A process of receiving a packet constituting stream data of stream communication in a communication path connecting the transmitting device and the receiving device;
A process of allocating a unique session identifier for each session to the received packet received in the receiving process, and managing the received packet and the session identifier in association with each other;
A process of identifying a packet type of the received packet;
If it is determined by the packet type identification processing that the received packet is a reception status message transmitted from the receiving device to the transmitting device, the transmitting device and the receiving device included in the received packet are connected from the received packet. A first quality value generation process for generating a stream communication quality value on the communication path;
When it is determined by the received packet type identification processing that the received packet is stream data transmitted from the transmitting device to the receiving device, the transmitting device and the observation device are connected based on information obtained from the received packet. Second quality value generation processing for generating a stream communication quality value in the communication path to be performed,
From the quality values generated in the first and second quality value generation processes associated with the same session identifier, a third value for generating a stream communication quality value in a communication path connecting the observation device and the reception device. Quality value generation processing,
And a computer-readable recording medium on which a program is recorded.
[0061]
(Supplementary Note 8) The quality of the stream communication is compared by comparing the quality value of the stream communication between the transmitting device and the observing device and between the observing device and the receiving device with a predetermined value set as a criterion for determining the quality. Quality judgment processing for judging the normality of
A computer-readable recording medium recording the program according to Supplementary Note 7, wherein the program causes a computer to execute the program.
[0062]
(Supplementary Note 9) A process of displaying the result of the quality of the stream communication between the transmission device and the observation device and between the observation device and the reception device determined in the quality determination process in session units,
A computer-readable recording medium recording the program according to Supplementary Note 8, wherein the program causes a computer to execute the program.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of an observation device.
FIG. 2 is a diagram illustrating a system configuration according to a first embodiment;
FIG. 3 is a diagram illustrating a system configuration according to a second embodiment;
FIG. 4 is a flowchart showing the contents of processing at the time of receiving a packet;
FIG. 5 is a diagram showing contents of a session management database according to the first embodiment;
FIG. 6 shows the contents of a received packet list.
FIG. 7 is a diagram showing contents of quality data;
FIG. 8 is a diagram showing contents of prescribed value data (reception side).
FIG. 9 is a diagram showing the contents of specified value data (transmission side).
FIG. 10 shows the contents of display data.
FIG. 11 is a diagram showing contents of a session management database according to the second embodiment;
FIG. 12 is a diagram showing a data format (stream data) of RTP.

Claims (3)

In a stream communication system including a transmitting device and a receiving device connected via a network constituted by a plurality of different network segments, the streaming system is connected between network segments forming a communication path connecting the transmitting device and the receiving device. An apparatus for observing network quality of stream communication in a communication path connecting a transmitting apparatus and a receiving apparatus,
Receiving processing means for receiving a packet constituting stream data of stream communication in a communication path connecting the transmitting device and the receiving device;
A session identification processing unit that allocates a unique session identifier for each session to a reception packet received using the reception processing unit, and manages the reception packet in association with the session identifier.
Packet type identification processing means for identifying a packet type of the received packet;
When the packet type identification processing means determines that the received packet is a reception status message transmitted from the receiving device to the transmitting device, the transmitting device and the receiving device included in the received packet are connected from the received packet. First quality value generation processing means for generating a stream quality value in the communication path to be performed,
When the received packet type identification processing means determines that the received packet is stream data transmitted from the transmitting device to the receiving device, the transmitting device and the observing device are determined based on information obtained from the received packet. Second quality value generation processing means for generating a stream communication quality value in a communication path to be connected,
From the quality values generated using the first and second quality value generation processing means associated with the same session identifier, a quality value of stream communication in a communication path connecting the observation device and the reception device is generated. Third quality value generation processing means,
A stream quality observing device comprising: In a stream communication system including a transmitting device and a receiving device connected via a network constituted by a plurality of different network segments, the streaming system is connected between network segments forming a communication path connecting the transmitting device and the receiving device. A program that causes a computer to function as a device for observing network quality of stream communication in a communication path connecting a transmitting device and a receiving device,
A process of receiving a packet constituting stream data of stream communication in a communication path connecting the transmitting device and the receiving device;
A process of allocating a unique session identifier for each session to the received packet received in the receiving process, and managing the received packet and the session identifier in association with each other;
A process of identifying a packet type of the received packet;
If it is determined by the packet type identification processing that the received packet is a reception status message transmitted from the receiving device to the transmitting device, the transmitting device and the receiving device are connected based on information obtained from the received packet. A first quality value generation process of generating a quality value of stream communication in a communication path to be performed,
When it is determined by the received packet type identification processing that the received packet is stream data transmitted from the transmitting device to the receiving device, the transmitting device and the observation device are connected based on information obtained from the received packet. Second quality value generation processing for generating a stream communication quality value in the communication path to be performed,
From the quality values generated in the first and second quality value generation processes associated with the same session identifier, a third value for generating a stream communication quality value in a communication path connecting the observation device and the reception device. Quality value generation processing,
A program that causes a computer to perform the following. In a stream communication system including a transmitting device and a receiving device connected via a network constituted by a plurality of different network segments, the streaming system is connected between network segments forming a communication path connecting the transmitting device and the receiving device. A computer-readable recording medium that records a program that causes a computer to function as a device that observes network quality of stream communication in a communication path connecting a transmitting device and a receiving device,
A process of receiving a packet constituting stream data of stream communication in a communication path connecting the transmitting device and the receiving device, and allocating a unique session identifier to the received packet received in the receiving process for each session, A process of associating and managing packets and session identifiers;
A process of identifying a packet type of the received packet;
If it is determined by the packet type identification processing that the received packet is a reception status message transmitted from the receiving device to the transmitting device, the transmitting device and the receiving device included in the received packet are connected from the received packet. A first quality value generation process for generating a stream communication quality value on the communication path;
When it is determined by the received packet type identification processing that the received packet is stream data transmitted from the transmitting device to the receiving device, the transmitting device and the observation device are connected based on information obtained from the received packet. Second quality value generation processing for generating a stream communication quality value in the communication path to be performed,
From the quality values generated in the first and second quality value generation processes associated with the same session identifier, a third value for generating a stream communication quality value in a communication path connecting the observation device and the reception device. Quality value generation processing,
And a computer-readable recording medium on which a program is recorded.
4.

Images