JPH1188234A - Optical subscriber's line transmitter and stand-by system optical transmission line monitoring method - Google Patents

Optical subscriber's line transmitter and stand-by system optical transmission line monitoring method

Info

Publication number
JPH1188234A
JPH1188234A JP9243018A JP24301897A JPH1188234A JP H1188234 A JPH1188234 A JP H1188234A JP 9243018 A JP9243018 A JP 9243018A JP 24301897 A JP24301897 A JP 24301897A JP H1188234 A JPH1188234 A JP H1188234A
Authority
JP
Japan
Prior art keywords
optical
branch
standby
delay measurement
transmission line
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.)
Granted
Application number
JP9243018A
Other languages
Japanese (ja)
Other versions
JP3781523B2 (en
Inventor
Kengo Hirano
賢吾 平野
Takeo Tode
武男 戸出
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.)
NEC Corp
Nippon Telegraph and Telephone Corp
Original Assignee
NEC Corp
Nippon Telegraph and Telephone Corp
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 NEC Corp, Nippon Telegraph and Telephone Corp filed Critical NEC Corp
Priority to JP24301897A priority Critical patent/JP3781523B2/en
Publication of JPH1188234A publication Critical patent/JPH1188234A/en
Application granted granted Critical
Publication of JP3781523B2 publication Critical patent/JP3781523B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Abstract

PROBLEM TO BE SOLVED: To monitor the transmission line of a stand-by system by allowing a control means to judge the normality of the optical transmission line of the stand-by system by the delay measurement of the stand-by system by a means executing delay measurement. SOLUTION: Two optical transmission lines are provided between a center equipment 11 and an optical star coupler 13, and the equipment 11 is provided with two optical subscriber's line interfaces 14 respectively connected to the two optical transmission lines and a control part 15 switching these two interfaces 14 between in-use one and stand-by one. A control part 15 sets one of the two interfaces 14 to an in-use system and a stand-by system at the time of starting communication and executes communication by using the in-use system. In addition, a delay measuring frame from a branch equipment 12 is received any time during communication to execute delay measurement between with the equipment 12 and executes the correction control of the transmitting position of an incoming frame. Delay measurement is executed also by a stand-by system so that the stand-by system can immediately cope with the switching of the in-use system and the stand-by system.

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】本発明はひとつのセンタ装置
と複数のブランチ装置とで光信号の送受信を行うパッシ
ブダブルスター(PDS)型の光加入者線伝送装置に関
する。特に、センタ装置の光加入者線インタフェースを
冗長化した場合の予備系光伝送路の監視に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a passive double star (PDS) type optical subscriber line transmission apparatus for transmitting and receiving optical signals between one center apparatus and a plurality of branch apparatuses. In particular, the present invention relates to monitoring of a standby optical transmission line when an optical subscriber line interface of a center device is made redundant.

【0002】[0002]

【従来の技術】光加入者線伝送装置として従来から、ひ
とつのセンタ装置と複数のブランチ装置とを光ファイバ
および光スターカプラにより接続し、センタ装置とブラ
ンチ装置とがそれぞれに接続された1本の光ファイバで
双方向に時間軸圧縮多重伝送(TCM)を行うPDS型
のものが知られている。また、センタ装置内の光加入者
線インタフェースおよび光スターカプラとの間の光伝送
路を冗長構成とすることも行われている。
2. Description of the Related Art Conventionally, as an optical line transmission device, one center device and a plurality of branch devices are connected by an optical fiber and an optical star coupler, and the center device and the branch device are connected to each other. There is known a PDS type that performs time-axis compression multiplex transmission (TCM) bidirectionally with an optical fiber. An optical transmission line between an optical subscriber line interface and an optical star coupler in a center device is also made to have a redundant configuration.

【0003】冗長構成がとられたPDS型の光加入者線
伝送装置において、センタ装置内の光加入者線インタフ
ェースを切り替える方法としては、オペレータからの制
御による強制切替と、現用系の動作に異常が検出された
場合に自動的に系切替を実施する自動切替とがある。こ
れらの系切替を行うには、予備系が正常であることが前
提条件となる。
[0003] In a PDS type optical subscriber line transmission apparatus having a redundant configuration, a method of switching an optical subscriber line interface in a center apparatus includes a forced switching by an operator's control and an abnormal operation of an active system. There is automatic switching in which system switching is automatically performed when is detected. To perform these system switching, it is a precondition that the standby system is normal.

【0004】PDS型の光加入者線伝送装置やその他の
光伝送装置における現用系および予備系の動作状態を監
視する技術としては、特開平3−98331号、同4−
294660号および同5−37471号の各公報(以
下、それぞれ「従来例公報1」、「従来例公報2」、
「従来例公報3」)という)に記載されたものがある。
従来例公報1に記載の技術では、光レベルでの出力監視
および現用・予備の切替を行うため、光送信部から伝送
路へ送出する光送信信号を分岐して伝送路からの光受信
信号と切り替えて光受信部に入力し、光送信部に入力さ
れる電気入力信号と光受信部からの電気出力信号とを比
較する。従来例公報2に記載の技術では、現用系の光バ
ースト信号との衝突を避けて予備系の光バースト信号送
信部の動作確認を行うため、バースト信号発生部から光
バースト信号送信部へのバースト信号の供給をそのバー
スト信号の休止期間に切り替える。従来例公報3に記載
の技術では、予備系の光送信器の動作監視を行うため、
予備系であっても常に動作状態にしておき、予備のとき
にはその出力を光シャッタで遮断する。
Japanese Patent Laid-Open Publication Nos. 3-98331 and 4-98331 disclose techniques for monitoring the operating states of the working system and the standby system in a PDS type optical subscriber line transmission device and other optical transmission devices.
Nos. 294660 and 5-37471 (hereinafter referred to as “Conventional Publication 1”, “Conventional Publication 2”,
"Conventional Publication 3").
In the technique described in the prior art publication 1, in order to perform output monitoring at the optical level and switching between active and standby, an optical transmission signal to be transmitted from the optical transmission unit to the transmission path is split into an optical reception signal from the transmission path. The signal is switched and input to the optical receiving unit, and the electrical input signal input to the optical transmitting unit is compared with the electrical output signal from the optical receiving unit. According to the technique described in Japanese Patent Application Laid-Open Publication No. 2000-252, the burst from the burst signal generator to the optical burst signal transmitter is checked in order to confirm the operation of the optical burst signal transmitter of the standby system while avoiding collision with the optical burst signal of the active system. The signal supply is switched to the rest period of the burst signal. According to the technique described in Publication 3 of the related art, the operation of the standby optical transmitter is monitored.
Even in the case of the standby system, the operating state is always maintained, and the output of the standby system is shut off by the optical shutter.

【0005】[0005]

【発明が解決しようとする課題】光伝送装置において予
備系が正常であるということは、予備系の送受信装置が
正常であるだけでなく、予備系の光伝送路が正常である
ことも必要である。PDS型の光加入者線伝送装置の場
合であれば、予備系の光加入者線インタフェースが未実
装でも故障でもないことと、予備系の光加入者線インタ
フェースと光スターカプラとの間の光伝送路が正常であ
ることとが必要である。
The fact that the standby system is normal in the optical transmission device means that not only the standby transmission / reception device but also the standby optical transmission line must be normal. is there. In the case of a PDS type optical subscriber line transmission device, there is no failure or failure of the standby optical subscriber line interface, and the optical connection between the standby optical subscriber line interface and the optical star coupler. It is necessary that the transmission path is normal.

【0006】しかし、PDS型の光加入者線伝送装置の
場合、予備系では、対向するブランチ装置との伝送路パ
ス(レイヤ)を確立することができない。その理由は、
センタ装置および各ブランチ装置がそれぞれ1本の光フ
ァイバで双方向通信を行うため、センタ装置内の予備系
光加入者インタフェースは、現用系側の通信を妨げるこ
とのないように、光出力を停止しなければならないから
である。このため、予備系について通常の伝送路監視は
できず、従来は、予備系の光加入者線インタフェースが
未実装でも故障でもない場合のみを切替可能としてい
た。
However, in the case of the PDS type optical subscriber line transmission device, the protection system cannot establish a transmission path (layer) with the opposing branch device. The reason is,
Since the center device and each branch device perform two-way communication with one optical fiber, the standby optical subscriber interface in the center device stops the optical output so as not to hinder communication on the working side. Because you have to do it. For this reason, normal transmission path monitoring cannot be performed for the standby system. Conventionally, switching can be performed only when the optical subscriber line interface of the standby system is not mounted or failed.

【0007】本発明は、このような課題を解決し、予備
系の伝送路監視が可能なPDS型の光加入者線伝送装置
およびその予備系光伝送路監視方法を提供することを目
的とする。
SUMMARY OF THE INVENTION It is an object of the present invention to provide a PDS type optical line transmission apparatus capable of monitoring a standby transmission line and a standby optical transmission line monitoring method. .

【0008】[0008]

【課題を解決するための手段】本発明の第一の観点は光
加入者線伝送装置であり、ひとつのセンタ装置と、複数
のブランチ装置と、センタ装置からの光信号をブランチ
装置に分配するとともに各ブランチ装置からの光信号を
ひとつに合波してセンタ装置に伝送する光合分波手段と
を備え、センタ装置と光合分波手段との間の少なくとも
センタ装置側には少なくとも二つの光伝送路が設けら
れ、センタ装置には、これらの光伝送路にそれぞれ接続
された少なくとも二つの光加入者線インタフェースと、
この少なくとも二つの光加入者線インタフェースを現用
と予備とで切り替える制御手段とを備え、この制御手段
には、現用系の光加入者線インタフェースの送信部およ
び受信部に加えて予備系の光加入者インタフェースの受
信部を動作させ、現用系および予備系のそれぞれについ
て、各ブランチ装置からセンタ装置へのフレーム送出位
置を補正するために各ブランチ装置が送出する遅延測定
フレームを受信して遅延測定を行う手段を含む光加入者
線伝送装置において、制御手段は、遅延測定を行う手段
による予備系の遅延測定結果により予備系の光伝送路の
正常性判定を行う手段を含むことを特徴とする。
A first aspect of the present invention is an optical subscriber line transmission device, which distributes one center device, a plurality of branch devices, and optical signals from the center device to the branch devices. And optical multiplexing / demultiplexing means for multiplexing the optical signals from each branch device into one and transmitting the multiplexed optical signal to the center device. At least two optical transmissions are provided between the center device and the optical multiplexing / demultiplexing device at least on the side of the center device. Channels, and the center device has at least two optical subscriber line interfaces respectively connected to these optical transmission lines,
Control means for switching between the at least two optical subscriber line interfaces between the working optical network interface and the protection optical network interface. Operating the receiving section of the user interface, and for each of the active system and the standby system, receives a delay measurement frame transmitted from each branch device to correct a frame transmission position from each branch device to the center device, and performs delay measurement. In the optical line transmission apparatus including the means for performing, the control means includes means for determining the normality of the optical transmission path of the protection system based on the result of the delay measurement of the protection system by the means for measuring the delay.

【0009】現用系の光加入者線インタフェースでは、
対向するブランチ装置がセンタ装置へ送出する上りフレ
ームの送出位置を補正する目的で、遅延測定フレームを
転送することで、センタ装置とブランチ装置との間の遅
延測定を随時行っている。この遅延測定情報は、予備系
が現用系に切り替えられたときに必要となることから、
予備系でも獲得しておく必要がある。このためには、
(1)現用系からコピーする、(2)光加入者線インタ
フェースの受信部のみを動作状態とし、ブランチ装置が
現用系に通知する遅延測定フレームを予備系でもモニタ
するの二つの方法がある。本発明では、(2)の場合に
着目し、その遅延測定結果を予備系の光伝送路の正常性
判定に用いる。このとき、センタ装置と通信を行うもの
として登録されたブランチ装置が少なくともひとつあ
り、かつ少なくともひとつのブランチ装置から遅延測定
結果が得られた場合に、予備系の光伝送路が正常である
と判断することがよい。逆に言うと、いずれのブランチ
装置についても遅延測定結果が得られない場合に、予備
系の光伝送路に異常があると判断する。また、センタ装
置と通信を行うものとして登録されたブランチ装置が少
なくともひとつあり、かつその登録されている少なくと
もひとつのブランチ装置から遅延測定結果が得られた場
合に、予備系の光伝送路が正常であると判断してもよ
い。
In the working optical subscriber line interface,
The delay measurement between the center device and the branch device is performed as needed by transferring a delay measurement frame for the purpose of correcting the transmission position of the upstream frame transmitted from the opposing branch device to the center device. Since this delay measurement information is required when the standby system is switched to the working system,
It is necessary to acquire in the spare system. To do this,
There are two methods: (1) copy from the working system, (2) activate only the receiving unit of the optical subscriber line interface, and monitor the delay measurement frame notified by the branch device to the working system also in the protection system. In the present invention, focusing on the case (2), the result of the delay measurement is used to determine the normality of the standby optical transmission line. At this time, when there is at least one branch device registered as communicating with the center device and the delay measurement result is obtained from at least one branch device, it is determined that the optical transmission line of the standby system is normal. It is better to do. Conversely, if no delay measurement result is obtained for any of the branch devices, it is determined that there is an abnormality in the standby optical transmission line. Also, if there is at least one branch device registered as communicating with the center device and a delay measurement result is obtained from at least one of the registered branch devices, the standby optical transmission line becomes normal. May be determined.

【0010】本発明の第二の観点は予備系光伝送路監視
方法であり、光加入者線インタフェースが現用系と予備
系とに冗長構成されたセンタ装置との間で複数のブラン
チ装置が現用系または予備系の光伝送路を共通に用いて
双方向の通信を行い、センタ装置は、各ブランチ装置か
らセンタ装置へのフレーム送出位置を補正するために各
ブランチ装置が送出する遅延測定フレームを現用系およ
び予備系の双方でそれぞれ受信して遅延測定を行うとと
もに、予備系の光伝送路が異常の場合に現用系と予備系
とを切り替えることがないように、予備系の遅延測定の
結果により予備系の光伝送路の正常性判定を行うことを
特徴とする。
A second aspect of the present invention is a method of monitoring a protection optical transmission line, wherein a plurality of branch devices are used between a center device in which an optical subscriber line interface is redundantly configured in a working system and a protection system. The bidirectional communication is performed by using the optical transmission line of the system or the standby system in common, and the center device transmits the delay measurement frame transmitted by each branch device to correct the frame transmission position from each branch device to the center device. Both the working system and the standby system receive and measure the delay, respectively, and the result of the delay measurement of the standby system so as not to switch between the working system and the standby system when the optical transmission line of the protection system is abnormal. Is used to determine the normality of the standby optical transmission line.

【0011】[0011]

【発明の実施の形態】図1は本発明の実施形態を示すブ
ロック構成図であり、PDS光加入者線伝送装置の構成
例を示す。このPDS光加入者線伝送装置は、ひとつの
センタ装置11と、複数のブランチ装置12と、センタ
装置11からの光信号をブランチ装置12に分配すると
ともに各ブランチ装置12からの光信号をひとつに合波
してセンタ装置11に伝送する光スターカプラ13とを
備える。センタ装置11と光スターカプラ13との間に
は二つの光伝送路が設けられ、センタ装置11には、こ
の二つの光伝送路にそれぞれ接続された二つの光加入者
線インタフェース14と、この二つの光加入者線インタ
フェース14を現用と予備とで切り替える制御部15と
を備える。
DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing an embodiment of the present invention, and shows a configuration example of a PDS optical subscriber line transmission apparatus. This PDS optical subscriber line transmission apparatus distributes an optical signal from one center device 11, a plurality of branch devices 12, and an optical signal from the center device 11 to the branch devices 12, and combines the optical signals from each branch device 12 into one. An optical star coupler 13 for multiplexing and transmitting to the center device 11. Two optical transmission lines are provided between the center device 11 and the optical star coupler 13. The center device 11 has two optical subscriber line interfaces 14 connected to the two optical transmission lines, respectively. A control unit 15 for switching between the two optical subscriber line interfaces 14 between active and standby is provided.

【0012】図2は制御部15による制御の流れを示
す。制御部15は、通信の開始時に二つの光加入者線イ
ンタフェース14の一方を現用系と他方を予備系に設定
し、現用系を用いて通信を行う。また、通信中には随
時、ブランチ装置からの遅延測定フレームを受信してブ
ランチ装置との間の遅延測定を行い、上りフレームの送
出位置の補正制御を行う。遅延測定は、現用系と予備系
とを切り替えたときに予備系がすぐに対応できるよう
に、予備系でも行われる。現用系に異常が発生したとき
には、予備系の遅延測定結果からその正常を判定し、正
常であれば、系切替を行う。予備系にも異常がある場合
には、現用系と予備系との双方に異常があることにな
る。この場合に、予備系光伝送路の異常時に系を現用系
から予備系に切り替えると、予備系ではブランチ装置と
の伝送路パスを張れず、伝送路警報の検出ができないた
め、サイレントアラームに陥ってしまうことがある。そ
こでこの場合には、予備系光伝送路を監視することので
きる公知の光伝送装置で一般に行われるように、伝送路
警報を確実に検出可能な現用系に維持し続け、サイレン
トアラームに陥ることを防止する。
FIG. 2 shows the flow of control by the control unit 15. The control unit 15 sets one of the two optical subscriber line interfaces 14 to the working system and the other to the protection system at the start of communication, and performs communication using the working system. Also, during communication, a delay measurement frame from the branch device is received at any time, delay measurement with the branch device is performed, and correction control of an upstream frame transmission position is performed. The delay measurement is also performed in the standby system so that the standby system can immediately respond when switching between the active system and the standby system. When an abnormality occurs in the active system, the normality is determined from the delay measurement result of the standby system, and if it is normal, system switching is performed. If the standby system also has an abnormality, both the working system and the standby system have an abnormality. In this case, if the system is switched from the active system to the standby system when the standby optical transmission line is abnormal, the standby system cannot establish a transmission path path to the branch device and cannot detect a transmission line alarm, resulting in a silent alarm. Sometimes. Therefore, in this case, as generally performed in a known optical transmission device capable of monitoring the protection system optical transmission line, the transmission line alarm is maintained in the working system that can be reliably detected, and a silent alarm occurs. To prevent

【0013】図3は現用、予備の設定制御の流れを示
す。双方向の通信を行うのであるから、現用系の光加入
者線インタフェース14については、送信部、受信部と
もに動作させる。一方、予備系の光加入者線インタフェ
ース14については、現用系側の通信を妨げないように
送信部を停止させ、受信部のみを動作させる。これによ
り、各ブランチ装置からの光信号の少なくとも一部を受
信して、予備系の光伝送路を監視することができる。
FIG. 3 shows a flow of setting control for working and standby. Since bidirectional communication is performed, the active optical subscriber line interface 14 is operated by both the transmission unit and the reception unit. On the other hand, as for the optical line interface 14 of the protection system, the transmission unit is stopped and only the reception unit is operated so as not to hinder communication on the working system side. This makes it possible to receive at least a part of the optical signal from each branch device and monitor the standby optical transmission line.

【0014】図4は予備系の正常性判定の制御の流れを
示す。予備系の正常性の判定は、予備系の光加入者線イ
ンタフェース14が実装されて正常に動作し、かつ予備
系の光加入者線インタフェース14と光スターカプラ1
3との間の伝送路が正常であることを条件とする。
FIG. 4 shows the flow of control for determining the normality of the standby system. The normality of the standby system is determined by operating the standby optical subscriber line interface 14 and operating normally.
3 is assumed to be normal.

【0015】図5は予備系の正常性判定の一例を説明す
る図である。予備系の光加入者線インタフェースが実装
されていることを「0」、未実装であることを「1」で
表し、正常に動作していることを「0」、異常があるこ
とを「1」、伝送路監視結果が正常であることを
「0」、異常であることを「1」で表すと、これらの値
のOR論理をとることで、予備系が正常であるときには
「0」、異常があるときには「1」の判定結果が得られ
る。
FIG. 5 is a diagram for explaining an example of the normality judgment of the standby system. "0" indicates that the standby optical network interface is installed, "1" indicates that it is not installed, "0" indicates that it is operating normally, and "1" indicates that it is abnormal. "0" indicates that the transmission path monitoring result is normal, and "1" indicates that the transmission path monitoring result is abnormal. By taking the OR logic of these values, "0" is displayed when the standby system is normal. When there is an abnormality, a determination result of “1” is obtained.

【0016】図6は各ブランチ装置に対する遅延測定結
果による予備系光伝送路の正常性判定の一例を説明する
図である。この判定では、センタ装置と通信を行うもの
として登録されたブランチ装置が少なくともひとつあ
り、かついずれのブランチ装置についても遅延測定結果
が得られない場合に、予備系の光伝送路に異常があると
判断する。ただし、全ブランチ装置が登録未完了時に
は、いずれのブランチ装置からの遅延測定結果が得られ
なくても伝送路異常とはしない。
FIG. 6 is a diagram for explaining an example of the determination of the normality of the protection optical transmission line based on the delay measurement result for each branch device. In this determination, if there is at least one branch device registered as communicating with the center device and no delay measurement result is obtained for any of the branch devices, it is determined that there is an abnormality in the optical transmission path of the standby system. to decide. However, when the registration of all the branch devices is not completed, even if the delay measurement result from any of the branch devices is not obtained, it is not considered that the transmission path is abnormal.

【0017】この判定のためには、各ブランチ装置につ
いて、遅延測定結果が得られた場合を「1」、NG(ノ
ーグッド)の場合を「0」で表し、登録状態が未完了を
「0」、完了している状態を「1」で表すものとする。
そして、全ブランチ装置の遅延測定結果がすべてNGか
否かを判定するために、全ブランチ装置の遅延測定結果
のNOR論理をとる。このとき、伝送路断状態時にはN
OR論理結果は「1」となり、伝送路正常時は「0」と
なる。また、少なくともひとつのブランチ装置が登録さ
れているかどうかを判定するために、全ブランチ装置の
登録状態のOR論理をとる。全ブランチ装置が登録未完
了時は、OR論理結果が「0」となり、1台以上が登録
完了しているときには「1」となる。NOR論理の結果
とOR論理の結果とのANDをとることで、予備系光伝
送路の監視結果として、伝送路正常時には「0」、伝送
路異常時は「1」が得られる。
For this determination, for each branch device, the case where the delay measurement result is obtained is represented by "1", the case of NG (no good) is represented by "0", and the registration status is "incomplete" by "0". , The completed state is represented by “1”.
Then, in order to determine whether all the delay measurement results of all the branch devices are NG, NOR logic of the delay measurement results of all the branch devices is taken. At this time, when the transmission path is disconnected, N
The OR logic result is “1” and is “0” when the transmission path is normal. Also, in order to determine whether at least one branch device is registered, the OR logic of the registered state of all branch devices is taken. When all the branch devices have not been registered, the OR logic result is "0", and when one or more devices have been registered, the result is "1". By taking the AND of the result of the NOR logic and the result of the OR logic, "0" is obtained as a monitoring result of the standby optical transmission line when the transmission line is normal, and "1" is obtained when the transmission line is abnormal.

【0018】図7は、図6に示した予備系光伝送路の正
常性判定について、ブランチ装置が3台の場合の真理値
表を示す。3台のブランチ装置がすべて登録未完了時
は、判定結果を「0」、すなわち正常とする。ブランチ
装置の登録台数が1台の場合は、この1台に対しての遅
延測定結果のみで判定する。ブランチ装置の登録台数が
2台の場合は、この2台に対しての遅延測定結果のみで
判定する。登録済みの2台のブランチ装置の遅延測定結
果がすべてNGの場合に、判定結果を「1」、すなわち
異常とする。ブランチ装置の登録台数が1台の場合は、
この1台に対しての遅延測定結果のみで判定する。ブラ
ンチ装置の登録台数が3台の場合は、この3台に対して
の遅延測定結果で判定する。登録済の3台のブランチ装
置の遅延測定結果がすべてNGの場合に、判定結果を
「1」、すなわち異常とする。
FIG. 7 shows a truth table for the normality determination of the standby optical transmission line shown in FIG. 6 in the case where three branch devices are provided. When the registration is not completed for all three branch devices, the determination result is “0”, that is, normal. If the number of registered branch devices is one, the determination is made only by the delay measurement result for this one device. When the number of registered branch devices is two, the determination is made only by the delay measurement result for the two devices. When the delay measurement results of the two registered branch devices are all NG, the determination result is “1”, that is, abnormal. If the number of registered branch devices is one,
Judgment is made only by the delay measurement result for this one device. If the number of registered branch devices is three, the determination is made based on the delay measurement results for the three devices. When all the delay measurement results of the three registered branch devices are NG, the determination result is “1”, that is, abnormal.

【0019】図8は各ブランチ装置に対する遅延測定結
果による予備系光伝送路の正常性判定の別の例を説明す
る図である。この例では、登録未完了のブランチ装置に
ついては光伝送路の正常性判定の対象から省くために、
各ブランチ装置毎に遅延測定結果と登録状態とのNAN
D論理をとる。登録完了時のみ遅延測定結果を有効と
し、未登録時は遅延測定結果によらず「1」にマスクす
る。また、全ブランチ装置が登録未完了であるか否かを
判定するために、各ブランチ装置の登録状態のOR論理
をとり、結果が「0」の場合を登録未完了とする。そし
て、登録完了している全ブランチ装置を対象とし、遅延
測定結果がすべてNGの場合を伝送路異常とするため
に、各ブランチ装置についての上述のNAND論理の結
果のAND論理をとり、結果が「1」の場合を伝送路異
常とする。ただし、全ブランチ装置が登録未完了時は伝
送路異常としないために、上述のAND論理の条件に、
各ブランチ装置の登録状態のOR論理結果を含める。
FIG. 8 is a diagram for explaining another example of determining the normality of the protection optical transmission line based on the delay measurement result for each branch device. In this example, in order to omit the branch device that has not been registered from the target of the optical transmission line normality determination,
NAN of delay measurement result and registration status for each branch device
Take D logic. The delay measurement result is validated only when registration is completed, and is masked to “1” when registration is not performed regardless of the delay measurement result. In addition, in order to determine whether or not all the branch devices have not been registered, the OR logic of the registered state of each branch device is taken, and if the result is “0”, the registration is not completed. Then, in order to set all the branch devices for which registration has been completed as targets, and to make the transmission path abnormal when all the delay measurement results are NG, the AND logic of the above-described NAND logic for each branch device is taken. A case of “1” is regarded as a transmission line abnormality. However, in order to prevent the transmission path from being abnormal when all the branch devices have not been registered, the conditions of the AND logic described above must be satisfied.
The OR logic result of the registration status of each branch device is included.

【0020】[0020]

【発明の効果】PDS型の光加入者線伝送装置におい
て、予備系光伝送路の異常時に系を現用系から予備系に
切り替えると、予備系ではブランチ装置との伝送路パス
を張れず、伝送路警報の検出ができないため、サイレン
トアラームに陥ってしまうことがある。これに対して本
発明によれば、PDS型の光加入者線伝送装置でも予備
系光伝送路監視が可能となり、予備系光伝送路の異常時
に系切替を抑止できるので、予備系光伝送路を監視する
ことのできる公知の光伝送装置で一般に行われるよう
に、伝送路警報を確実に検出可能な現用系に維持し続
け、サイレントアラームに陥ることを防止できる。
In the optical subscriber line transmission apparatus of the PDS type, when the system is switched from the working system to the protection system when the protection system optical transmission line is abnormal, the protection system cannot establish a transmission path path with the branch device, and the transmission is performed. Since a road alarm cannot be detected, a silent alarm may occur. On the other hand, according to the present invention, the PDS type optical network unit can also monitor the standby optical transmission line, and can suppress system switching when the standby optical transmission line is abnormal. As is generally the case with a known optical transmission device that can monitor the transmission line alarm, the transmission line alarm can be maintained in the working system that can be reliably detected, and the occurrence of a silent alarm can be prevented.

【0021】また、予備系光伝送路の異常時に系を現用
系から予備系に切り替えると、予備系ではブランチ装置
との伝送路パスが張れず、通信サービスの運用ができな
くなるが、本発明によれば予備系光伝送路が正常時の場
合にのみ系切替を実施するため、確実に系切替実施後の
通信サービスの運用を保証することができる。
Further, if the system is switched from the working system to the protection system when the protection system optical transmission line is abnormal, the protection system cannot establish a transmission path path with the branch device and cannot operate the communication service. According to this, since system switching is performed only when the standby system optical transmission line is normal, operation of the communication service after system switching can be reliably ensured.

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

【図1】本発明の実施形態を示すブロック構成図。FIG. 1 is a block diagram showing an embodiment of the present invention.

【図2】制御部による制御の流れを示す図。FIG. 2 is a diagram showing a flow of control by a control unit.

【図3】現用、予備の設定制御の流れを示す図。FIG. 3 is a diagram showing a flow of setting control of working and standby.

【図4】予備系の正常性判定の制御の流れを示す図。FIG. 4 is a diagram showing the flow of control for determining the normality of a standby system.

【図5】予備系の正常性判定の一例を説明する図。FIG. 5 is a diagram for explaining an example of a normality determination of a standby system.

【図6】各ブランチ装置に対する遅延測定結果による予
備系光伝送路の正常性判定の一例を説明する図。
FIG. 6 is a diagram illustrating an example of determining the normality of a standby optical transmission line based on a delay measurement result for each branch device.

【図7】ブランチ装置が3台の場合の予備系光伝送路の
正常性判定の真理値表を示す図。
FIG. 7 is a diagram showing a truth table for determining the normality of the standby optical transmission line when the number of branch devices is three.

【図8】各ブランチ装置に対する遅延測定結果による予
備系光伝送路の正常性判定の別の例を説明する図。
FIG. 8 is a view for explaining another example of determining the normality of the standby optical transmission line based on the delay measurement result for each branch device.

【符号の説明】[Explanation of symbols]

11 センタ装置 12 ブランチ装置 13 光スターカプラ 14 光加入者線インタフェース 15 制御部 DESCRIPTION OF SYMBOLS 11 Center apparatus 12 Branch apparatus 13 Optical star coupler 14 Optical subscriber line interface 15 Control part

───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.6 識別記号 FI H04L 12/24 H04L 11/08 12/26 ──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. 6 Identification code FI H04L 12/24 H04L 11/08 12/26

Claims (6)

【特許請求の範囲】[Claims] 【請求項1】 ひとつのセンタ装置と、複数のブランチ
装置と、前記ひとつのセンタ装置からの光信号を前記複
数のブランチ装置に分配するとともに前記複数のブラン
チ装置のそれぞれからの光信号をひとつに合波して前記
ひとつのセンタ装置に伝送する光合分波手段とを備え、 前記センタ装置と前記光合分波手段との間の少なくとも
前記センタ装置側には少なくとも二つの光伝送路が設け
られ、 前記センタ装置には、前記少なくとも二つの光伝送路に
それぞれ接続された少なくとも二つの光加入者線インタ
フェースと、この少なくとも二つの光加入者線インタフ
ェースを現用と予備とで切り替える制御手段とを備え、 この制御手段には、現用系の光加入者線インタフェース
の送信部および受信部に加えて予備系の光加入者インタ
フェースの受信部を動作させ、現用系および予備系のそ
れぞれについて、各ブランチ装置から前記センタ装置へ
のフレーム送出位置を補正するために各ブランチ装置が
送出する遅延測定フレームを受信して遅延測定を行う手
段を含む光加入者線伝送装置において、 前記制御手段は、前記遅延測定を行う手段による予備系
の遅延測定結果により予備系の光伝送路の正常性判定を
行う手段を含むことを特徴とする光加入者線伝送装置。
An optical signal from one center device, a plurality of branch devices, and an optical signal from the one center device are distributed to the plurality of branch devices, and optical signals from each of the plurality of branch devices are combined into one. Optical multiplexing / demultiplexing means for multiplexing and transmitting to the one center device, at least two optical transmission paths are provided on at least the center device side between the center device and the optical multiplexing / demultiplexing device, The center device includes at least two optical subscriber line interfaces respectively connected to the at least two optical transmission lines, and control means for switching the at least two optical subscriber line interfaces between active and standby, This control means includes, in addition to the transmitting and receiving units of the working optical subscriber line interface, the protection optical subscriber interface. Means for operating a receiving unit, receiving delay measurement frames transmitted from each branch device to correct a frame transmission position from each branch device to the center device, and measuring delay for each of the active system and the standby system An optical subscriber line transmission apparatus comprising: an optical transmission line, wherein the control means includes means for determining the normality of the optical transmission line of the standby system based on the result of the delay measurement of the standby system by the delay measurement unit. Subscriber line transmission equipment.
【請求項2】 前記正常性判定を行う手段は、前記セン
タ装置と通信を行うものとして登録されたブランチ装置
が少なくともひとつあり、かつ少なくともひとつのブラ
ンチ装置から遅延測定結果が得られた場合に、予備系の
光伝送路が正常であると判断する手段を含む請求項1記
載の光加入者線伝送装置。
2. The method according to claim 1, wherein the means for performing the normality determination includes: when at least one branch device is registered as communicating with the center device, and when a delay measurement result is obtained from at least one branch device, 2. The optical subscriber line transmission device according to claim 1, further comprising means for judging that the standby optical transmission line is normal.
【請求項3】 前記正常性判定を行う手段は、前記セン
タ装置と通信を行うものとして登録されたブランチ装置
が少なくともひとつあり、かつその登録されている少な
くともひとつのブランチ装置から遅延測定結果が得られ
た場合に、予備系の光伝送路が正常であると判断する手
段を含む請求項1記載の光加入者線伝送装置。
3. The means for performing the normality determination includes at least one branch device registered as communicating with the center device, and obtaining a delay measurement result from at least one registered branch device. 2. The optical subscriber line transmission apparatus according to claim 1, further comprising means for judging that the optical transmission line of the standby system is normal when the transmission is performed.
【請求項4】 光加入者線インタフェースが現用系と予
備系とに冗長構成されたセンタ装置との間で複数のブラ
ンチ装置が現用系または予備系の光伝送路を共通に用い
て双方向の通信を行い、 前記センタ装置は、各ブランチ装置から前記センタ装置
へのフレーム送出位置を補正するために各ブランチ装置
が送出する遅延測定フレームを現用系および予備系の双
方でそれぞれ受信して遅延測定を行うとともに、予備系
の光伝送路が異常の場合に現用系と予備系とを切り替え
ることがないように、予備系の遅延測定の結果により予
備系の光伝送路の正常性判定を行う予備系光伝送路監視
方法。
4. A plurality of branch units are provided between a central unit in which an optical subscriber line interface is redundantly configured in an active system and a standby system, and a plurality of branch units share a bidirectional optical transmission line of an active system or a standby system. The center device performs communication, and receives delay measurement frames transmitted by each branch device to correct the frame transmission position from each branch device to the center device in both the active system and the standby system, and performs delay measurement. In addition to the above, when the optical transmission line of the standby system is abnormal, the standby system determines the normality of the optical transmission line of the standby system based on the result of the delay measurement of the standby system so as not to switch between the active system and the standby system. System optical transmission line monitoring method.
【請求項5】 前記センタ装置と通信を行うものとして
登録されたブランチ装置が少なくともひとつあり、かつ
少なくともひとつのブランチ装置から遅延測定結果が得
られた場合に、予備系の光伝送路が正常であると判断す
る請求項4記載の予備系光伝送路監視方法。
5. When there is at least one branch device registered as communicating with the center device and when a delay measurement result is obtained from at least one branch device, the standby optical transmission path is normal. 5. The method of monitoring a standby optical transmission line according to claim 4, wherein it is determined that there is a backup.
【請求項6】 前記センタ装置と通信を行うものとして
登録されたブランチ装置が少なくともひとつあり、かつ
その登録されている少なくともひとつのブランチ装置か
ら遅延測定結果が得られた場合に、予備系の光伝送路が
正常であると判断する請求項4記載の予備系光伝送路監
視方法。
6. A standby optical system when at least one branch device registered as communicating with the center device and a delay measurement result is obtained from at least one registered branch device. The method according to claim 4, wherein the transmission line is determined to be normal.
JP24301897A 1997-09-08 1997-09-08 Optical subscriber line transmission apparatus and standby optical transmission line monitoring method Expired - Fee Related JP3781523B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP24301897A JP3781523B2 (en) 1997-09-08 1997-09-08 Optical subscriber line transmission apparatus and standby optical transmission line monitoring method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP24301897A JP3781523B2 (en) 1997-09-08 1997-09-08 Optical subscriber line transmission apparatus and standby optical transmission line monitoring method

Publications (2)

Publication Number Publication Date
JPH1188234A true JPH1188234A (en) 1999-03-30
JP3781523B2 JP3781523B2 (en) 2006-05-31

Family

ID=17097659

Family Applications (1)

Application Number Title Priority Date Filing Date
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Country Status (1)

Country Link
JP (1) JP3781523B2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001093489A1 (en) * 2000-05-31 2001-12-06 Mitsubishi Denki Kabushiki Kaisha Redundant optical multiple-branch communication system
JP2009232221A (en) * 2008-03-24 2009-10-08 Fujitsu Ltd Optical communication system

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001093489A1 (en) * 2000-05-31 2001-12-06 Mitsubishi Denki Kabushiki Kaisha Redundant optical multiple-branch communication system
JP2009232221A (en) * 2008-03-24 2009-10-08 Fujitsu Ltd Optical communication system
JP4531098B2 (en) * 2008-03-24 2010-08-25 富士通オプティカルコンポーネンツ株式会社 Optical communication system
US8195050B2 (en) 2008-03-24 2012-06-05 Fujitsu Limited Optical transmission apparatus, subscriber apparatus and optical communication system

Also Published As

Publication number Publication date
JP3781523B2 (en) 2006-05-31

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