JPS6046636A - Method for processing inter-node communication fault - Google Patents

Method for processing inter-node communication fault

Info

Publication number
JPS6046636A
JPS6046636A JP58154698A JP15469883A JPS6046636A JP S6046636 A JPS6046636 A JP S6046636A JP 58154698 A JP58154698 A JP 58154698A JP 15469883 A JP15469883 A JP 15469883A JP S6046636 A JPS6046636 A JP S6046636A
Authority
JP
Japan
Prior art keywords
station node
transmission line
data
failure
highway
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.)
Pending
Application number
JP58154698A
Other languages
Japanese (ja)
Inventor
Yasuhiro Nakahara
中原 康裕
Teruyoshi Mita
三田 照義
Yoshihiro Kitano
北野 美裕
Hitoshi Negishi
仁 根岸
Osamu Nakamura
修 中村
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.)
Fujitsu Ltd
Original Assignee
Fujitsu Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP58154698A priority Critical patent/JPS6046636A/en
Publication of JPS6046636A publication Critical patent/JPS6046636A/en
Pending legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L12/00Data switching networks
    • H04L12/28Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
    • H04L12/42Loop networks
    • H04L12/437Ring fault isolation or reconfiguration

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Small-Scale Networks (AREA)

Abstract

PURPOSE:To form the maximum highway from which a defective station node (SN) has been removed by using a self-transmission line switching function of an SN due to the fault of a transmission line to generate a false transmission line fault and switch the selecting system of SNs after the defective SN. CONSTITUTION:A false transmission line fault generating part 23 is formed on a station node SN and turns a switch SW2 or a switch SW3 on the basis of a false transmission line fault generating command from a supervisory unit SV. When the supervisory unit SV applies the false transmission line fault generating command to a station node SN1, transmission line faults are generated in respective nodes SNi after said node SN1 and the nodes SN2-SN5 detect the faults by respective supervisory parts LNCOs and turn the ''0'' system to the ''1'' system. Since the supervisory unit SV sends data to both systems, the nodes SN3-SN5 can receive data from the supervisory unit SV through the ''1'' system.

Description

【発明の詳細な説明】 (イ)発明の技術分野 本発明は、環状の2重伝送路と、複数のステーションノ
ードと、ハイウェイ監視装置とから構成されるデータハ
イウェイシステムに関し、特に、ステーションノード内
に擬似伝送路障害を発生させる制御部を設はステーショ
ンノードの障害が発生した場合に障害ステーションノー
ドの手前で擬似伝送路障害を発生させ、障害ステーショ
ンノード以降のステーションノードをもう一方の伝送路
に切替えさせてハイウェイ監視装置との通信が出来るよ
うにし、障害の無い最大のハイウェイ構成を築くことが
できるようにしたノード間通信障害処理方式に関する。
DETAILED DESCRIPTION OF THE INVENTION (a) Technical field of the invention The present invention relates to a data highway system consisting of a circular dual transmission line, a plurality of station nodes, and a highway monitoring device. A control unit that generates a pseudo transmission line fault is installed in the station node, and when a fault occurs in a station node, a pseudo transmission line fault is generated before the faulty station node, and the station nodes after the faulty station node are connected to the other transmission line. The present invention relates to an inter-node communication failure handling method that enables communication with a highway monitoring device by switching between nodes, thereby making it possible to build the maximum highway configuration free of failures.

(ロ)従来技術と問題点 第1図は、データハイウェイシステムの1構成例であり
、1台のハイウェイ監視装置1 (以下、SVと呼ぶ)
と複数台のステーションノード2 (以下、SNと呼ぶ
)を環状の2重伝送路(0系伝送路3−0.1系伝送路
3−1)に接続し2通信路を構成し、各ステーションノ
ード2に接続されている図示しない端末装置間のデータ
通信は、この環状伝送路を使用して行なうようにされて
いる。
(b) Prior art and problems Figure 1 shows one configuration example of a data highway system, in which one highway monitoring device 1 (hereinafter referred to as SV)
and a plurality of station nodes 2 (hereinafter referred to as SN) are connected to a circular double transmission path (0 system transmission path 3-0.1 system transmission path 3-1) to form two communication paths, and each station Data communication between terminal devices (not shown) connected to the node 2 is performed using this circular transmission path.

そしてこの場合、第2図に示すようなフレーム。And in this case, a frame as shown in FIG.

すなわち、1つのフレーム同期パターン4(以降FHと
呼ぶ)と、5V−3N間の通信用スロット5 (以降D
Lcと呼ぶ)と、データ端末間のデータを送受信するた
めの1つ以上のタイムスロットNはDLCを使用して相
互の通信用手順に基づいて回線属性変更、SNの状態転
送等のデータの授受信を行う。
That is, one frame synchronization pattern 4 (hereinafter referred to as FH) and communication slot 5 between 5V and 3N (hereinafter referred to as D
Lc) and one or more time slots N for transmitting and receiving data between data terminals use DLC to exchange data such as changing line attributes and transferring SN status based on mutual communication procedures. Perform reception.

第3図は、従来のSNの構成例である。FIG. 3 shows an example of the configuration of a conventional SN.

従来技術では、第3図に示すように、0系伝送路3−0
からのフレームを光/電気変換部10 (以降OEOと
呼ぶ)で受け、光から電気へ変換し、選択スイッチ(S
elect 5W)1 (以降、SWlと呼ぶ)を経由
して、シリアルデータをパラレルデータへ変換するシリ
アル/パラレル変換部11 (以降SPと呼ぶ)に渡し
パラレルデータにする。パラレルに変換されたデータは
、共通制御部12 (以降CCと呼ぶ)に渡すと供に、
フレームカウンタ部13 (以降FCと呼ぶ)に渡す。
In the conventional technology, as shown in FIG.
The optical/electrical converter 10 (hereinafter referred to as OEO) receives the frame from the
5W) 1 (hereinafter referred to as SWl), the data is passed to a serial/parallel conversion unit 11 (hereinafter referred to as SP) that converts serial data into parallel data, and converted into parallel data. The data converted into parallel data is passed to the common control unit 12 (hereinafter referred to as CC), and
It is passed to the frame counter section 13 (hereinafter referred to as FC).

FCはフレーム中のF Hを監視しており、F Hを受
信するとカウンタを初期化し、以降DLC,及びTSを
受信する毎にCC部へ通知する。CCは、SPから渡さ
れたデータとFCからのカウント通知によりD L C
部であれば、ノード間通信制御部14(以降DCと呼ぶ
)へ渡し、TS部であれば、回線対応部16 (以降L
Sと呼ぶ)へ渡す。DCは受信中であれば渡されたデー
タを処理し、プログラム制御部15 (以降PCと呼ふ
)へ受信データを渡す。また送信中であれば、前もって
用意されていたデータをセットしてCCへ返す。LSは
、渡されたデータを自分のものかチェックし、自分のも
のであれば受信データをデータ端末に送出すると供に、
データ端末からの受信データを当該TSヘセットする。
The FC monitors the FH in the frame, and when it receives the FH, it initializes a counter, and thereafter notifies the CC section every time it receives a DLC or TS. The CC uses the data passed from the SP and the count notification from the FC.
If it is a TS part, it is passed to the inter-node communication control part 14 (hereinafter referred to as DC), and if it is a TS part, it is passed to the line correspondence part 16 (hereinafter referred to as L).
(call it S). If the DC is receiving data, it processes the received data and passes the received data to the program control unit 15 (hereinafter referred to as PC). If transmission is in progress, previously prepared data is set and returned to the CC. The LS checks whether the passed data is its own, and if it is its own, it sends the received data to the data terminal, and
Set the received data from the data terminal to the relevant TS.

自分のものでなければ、何の処理も行なわない。CCは
、DC及びLSより返されてきたデータをパラレルシリ
アル変換部17 (以降PSと呼ぶ)へ渡し、パラレル
データをシリアルデータへ変換し選択スイッチ(Sel
ectSW)2 (以降SW2と呼ぶ)を経由して、電
気/光変換部18 (以降800と呼ぶ)へ渡し、電気
から光へ変換して伝送路3−〇へ送出する。伝送路監視
部21(以降LNCOと呼ぶ)は、OROで受信した信
号の監視をしており、異常を検出するとPCへ通知する
。また、θ系に対して1系用の光/電気変換部19 (
以降OEIと呼ぶ)。
If it's not mine, I won't do anything with it. The CC passes the data returned from the DC and LS to the parallel-to-serial converter 17 (hereinafter referred to as PS), converts the parallel data to serial data, and selects the selection switch (Sel).
ectSW) 2 (hereinafter referred to as SW2), it is passed to the electricity/optical converter 18 (hereinafter referred to as 800), where it is converted from electricity to light and sent to the transmission line 3-0. The transmission path monitoring unit 21 (hereinafter referred to as LNCO) monitors the signals received by the ORO, and notifies the PC when an abnormality is detected. In addition, for the θ system, an optical/electrical converter 19 for the 1 system (
(hereinafter referred to as OEI).

電気/光変換部20(以降EOIと呼ぶ)、伝送路監視
部22(以降LNC1と呼ぶ)があり、0系又は1系の
どちらを選択するかは、SWIにより切替え、又、送出
時の選択はSW2.3により行う。0糸使用時のSW方
向については、SWIはOEOからの入力を選択し、S
W2はPSからの出力を選択し、SW3はOEIからの
入力を選択するよう動作する。
There is an electrical/optical converter 20 (hereinafter referred to as EOI) and a transmission line monitor 22 (hereinafter referred to as LNC1), and whether to select the 0 system or 1 system is switched by SWI or selected at the time of transmission. is performed by SW2.3. Regarding the SW direction when using 0 yarn, SWI selects the input from OEO, and
W2 operates to select the output from the PS, and SW3 operates to select the input from the OEI.

また0糸使用時に伝送路障害である光異常をLNCOで
検出すると、PCへ通知し、PCでは1系へ切替えを行
う。(SWlをOEIからの入力。
Furthermore, when the LNCO detects an optical abnormality, which is a transmission path failure, when using the 0th thread, it notifies the PC, and the PC switches to the 1st system. (Input SWl from OEI.

SW2をOEOからの入力、SW3をPSからの出力へ
と切替える。) また、SVでは、SNに対する通信情報を0系と1系へ
と送出する。(SW2及びSW3をPCからの出力とす
る) 第4図のループ構成で、SV及び全SNがO系を使用し
て通信を行なっている時、SN2のDCが障害になって
受信したフレームのDLCを送出できなくなった場合、
SvからのデータをSN2以降に伝達できなくなる。ま
たSNI、2からSVへ送出しようとするデータも伝わ
らなくなり、全ての5V−3N間の通信ができなくなる
。この場合SVでは、自分の送出したデータが受信でき
なくなるので第5図に示すように、sVから近いSN(
本図では5NI)より順に0系と1系を使用してループ
バック指示を行ないデータの送・受信ができれば、ルー
プバックを解除させて、次々とチェックしていく。この
時SN2に対してループハック指示をしても、障害のた
め、指示及び送・受信ができないので、SN2が障害と
分かるが、SN2以降のSN3,4.5に対しては、指
示することができず、ハイウェイ構成が、第6図のよう
にSVとSNIのみとなり、従来方式では、SN2のみ
の障害でSN3,4.5の通信が出来なくなるという欠
点がある。
Switch SW2 to input from OEO, and switch SW3 to output from PS. ) Also, the SV sends communication information for the SN to the 0 system and 1 system. (SW2 and SW3 are the output from the PC) In the loop configuration shown in Figure 4, when the SV and all SNs are communicating using the O system, the DC of SN2 becomes a failure and the received frame If you are unable to send DLC,
Data from Sv cannot be transmitted to SN2 or later. Also, data that is to be sent from SNI2 to SV will not be transmitted, and all communication between 5V and 3N will be impossible. In this case, the SV will not be able to receive the data it sent, so as shown in Figure 5, the SN (
In this figure, a loopback instruction is performed using the 0 system and 1 system in order from 5NI), and if data can be sent and received, the loopback is canceled and checks are performed one after another. At this time, even if you issue a loop hack instruction to SN2, you will not be able to receive instructions or send/receive due to the failure, so you will know that SN2 is the failure, but you should give instructions to SN3 and 4.5 after SN2. As a result, the highway configuration becomes only SV and SNI as shown in FIG. 6, and the conventional system has the disadvantage that communication at SN3 and 4.5 becomes impossible due to a failure in only SN2.

(ハ)発明の目的 本発明は上記の点を解決し、障害SN以降のSNとSV
間との通信ルートを確保し、障害SNのみを除いたデー
タハイウェイ構成を可能にすることを目的としている。
(C) Purpose of the Invention The present invention solves the above points and
The purpose is to secure a communication route between the two and to enable a data highway configuration excluding only the faulty SN.

(ニ)発明の構成 上記目的を達成するために本発明は、環状の2重伝送路
と、該伝送路中にもうけられデータ端末と伝送路間およ
び内部の制御部と伝送路間の信号およびデータの授受を
制御しかつ一方の伝送路が障害になったとき他系の伝送
路に切換える機能を有するステーションノードと、前記
ステーションノードおよび伝送路を監視/制御するハイ
ウェイ監視装置とから構成されるデータハイウェイシス
テムにおいて、前記ステーションノードに擬似的に伝送
路障害を発生させる制御部をもうけ、任意のステーショ
ンノードの障害により前記ハイウェイ監視装置と各ステ
ーションノード間の通常の通信が途絶した場合、前記ハ
イウェイ監視装置は障害ステーションノードを探索検出
し、当該障害ステーションノードの手前のステーション
ノードにおいて当該ハイウェイ監視装置からの指示によ
り擬似的に伝送路障害を発生させ当該伝送路障害を後位
ステーションノードに順次伝達し、当該障害ステーショ
ンノードおよび以降のステーションノードにおいて伝送
路を他系の伝送路に切替えさせ、前記ハイウェイ監視装
置と前記障害ステーションノードより後位のステーショ
ンノードとの通信を可能なように構成したことを特徴と
する。
(d) Structure of the Invention In order to achieve the above object, the present invention provides a ring-shaped double transmission line, and a signal and a signal between a data terminal and the transmission line and between an internal control unit and the transmission line provided in the transmission line. Consisting of a station node that controls data exchange and has the function of switching to another transmission line when one transmission line becomes impaired, and a highway monitoring device that monitors and controls the station node and transmission line. In the data highway system, a control unit is provided that causes a pseudo transmission path failure in the station node, and when normal communication between the highway monitoring device and each station node is interrupted due to a failure in any station node, the highway The monitoring device searches for and detects a faulty station node, generates a pseudo transmission line fault at the station node before the faulty station node based on instructions from the highway monitoring equipment, and sequentially transmits the transmission line fault to subsequent station nodes. and the transmission path is switched to a transmission path of another system at the faulty station node and subsequent station nodes, so that communication between the highway monitoring device and a station node subsequent to the faulty station node is possible. It is characterized by

(ホ)発明の実施例 第7図は本発明の実施例のSNの構成図であり、第3図
と同一番号のものは同一名称のものを示している。第3
図に示す従来例と異なる点は、擬似伝送路障害発生部2
3(以降FLNERと呼ぶ)を設け、SVよりの擬似伝
送路障害発生指示に対して、SW2またはSW3を、F
LNBRよりの出力を選択するようPCより制御するよ
うにした点である。これにより第8図に示すように、S
VからSNIに対して、擬似伝送路障害発生指示を行な
うと、SNI以降の各SHにおいて伝送路障害が発生す
る。そのため、SN”2〜SN5は各々のLNCOによ
り伝送路障害を検出し、0系を選択していたのを1系選
択に切替える。SVでは両系にデータを送出しているの
で、SN3〜SN5は1系よりSVのデータを受信する
ことができる。
(E) Embodiment of the Invention FIG. 7 is a block diagram of an SN according to an embodiment of the invention, and the same numbers as in FIG. 3 indicate the same names. Third
The difference from the conventional example shown in the figure is that the pseudo transmission path fault generation section 2
3 (hereinafter referred to as FLNER), and in response to a pseudo transmission line fault occurrence instruction from the SV, SW2 or SW3 is
The point is that the PC controls the selection of the output from the LNBR. As a result, as shown in FIG.
When V instructs SNI to generate a pseudo transmission line failure, a transmission line failure occurs in each SH after SNI. Therefore, SN"2 to SN5 detect a transmission path failure by each LNCO and switch from selecting system 0 to system 1. Since SV sends data to both systems, SN3 to SN5 can receive SV data from the 1st system.

よってSVはSN3に対して、1系から0系へのループ
バック指示を行なわせるとともに、SN1に対して、擬
似伝送路障害発生解除指令及び、0系から1系へのルー
プハック指示を行なわせることにより、第9図のような
SN2を除いたハイウェイ構成を築くことができる。
Therefore, the SV instructs SN3 to loop back from the 1 system to the 0 system, and also instructs SN1 to cancel the occurrence of a pseudo transmission line fault and to instruct the loop hack from the 0 system to the 1 system. By doing so, it is possible to construct a highway configuration excluding SN2 as shown in FIG.

(へ)発明の詳細 な説明したように本発明は、伝送路障害によるSNの自
主伝送路切替え機能を利用し、SVよりの指令により、
SNで擬似伝送路障害を発生させ、障害SN以降のSN
の選択系を切替えさせ、SVからの指令を受信できるよ
うにしたので、障害SNを除いた最大のハイウェイ構成
を提供できる効果がある。
(f) Detailed Description of the Invention As described above, the present invention utilizes the SN's autonomous transmission path switching function due to a transmission path failure, and in response to a command from the SV,
A pseudo transmission line fault is generated at the SN, and the SNs after the faulty SN
Since the selection system of the SV can be switched and commands from the SV can be received, it is possible to provide the maximum highway configuration excluding the faulty SN.

【図面の簡単な説明】[Brief explanation of the drawing]

第1図はデータハイウェイシステムの1構成例を示す図
、第2図はフレームの構成例を示す図。 第3図は従来のステーションノードの1構成例を示す図
、第4図、第5図は従来の制御方式の説明図、第6図は
従来の障害発生時におけるデータハイウェイシステムの
構成例を示す図、第7図は本発明の実施例のステーショ
ンノードの構成図、第8図は本発明の制御方式の説明図
、第9図は本発明の障害発生時におけるデータハイウェ
イシステムの構成例を示す図である。 第7図において、3−0は0系伝送路、3−1は1系伝
送路、21.22は伝送路監視部、23は擬似伝送路障
害発生部、SWI〜SW3は選択スイッチである。 芽 4− 図 第 5 図 927− 芽乙圀
FIG. 1 is a diagram showing an example of the configuration of a data highway system, and FIG. 2 is a diagram showing an example of the configuration of a frame. FIG. 3 is a diagram showing an example of the configuration of a conventional station node, FIGS. 4 and 5 are explanatory diagrams of conventional control methods, and FIG. 6 is a diagram showing an example of the configuration of a conventional data highway system in the event of a failure. 7 is a configuration diagram of a station node according to an embodiment of the present invention, FIG. 8 is an explanatory diagram of a control method of the present invention, and FIG. 9 is a configuration example of a data highway system in the event of a failure according to the present invention. It is a diagram. In FIG. 7, 3-0 is a 0-system transmission line, 3-1 is a 1-system transmission line, 21.22 is a transmission line monitoring section, 23 is a pseudo transmission line failure generating section, and SWI to SW3 are selection switches. Bud 4- Figure 5 Figure 927- Meotokuni

Claims (1)

【特許請求の範囲】[Claims] 環状の2重伝送路と、該伝送路中にもうけられデータと
伝送路間および内部の制御部と伝送路間の信号およびデ
ータの授受を制御しかつ一方の伝送路が障害になったと
き他系の伝送路に切換える機能を有するステーションノ
ードと、前記ステーションノードおよび伝送路を監視/
制御するハイウェイ監視装置とから構成されるデータハ
イウェイシステムにおいて、前記ステーションノードに
擬似的に伝送路障害を発生させる制御部をもうけ、任意
のステーションノードの障害により前記ハイウェイ監視
装置と各ステーションノード間の通常の通信が途絶した
場合、前記ハイウェイ監視装置は障害ステーションノー
ドを探索検出し、当該障害ステーションノードの手前の
ステーションノードにおいて当該ハイウェイ監視装置か
らの指示により擬似的に伝送路障害を発生させ当該伝送
路障害を後位ステーションノードに順次伝達し、当該障
害ステーションノードおよび以降のステーションノード
において伝送路を他系の伝送路に切替えさせ、前記ハイ
ウェイ監視装置と前記障害ステーションノードより後位
のステーションノードとの通信を可能なように構成した
ことを特徴とするノード間通信障害処理方式。
A ring-shaped dual transmission line, a control unit installed in the transmission line to control the exchange of signals and data between the data and the transmission line, and between an internal control unit and the transmission line, and when one transmission line becomes a failure, etc. A station node having a function of switching to a system transmission path, and a station node that monitors/monitors the station node and transmission path.
A data highway system comprising a highway monitoring device to control the data highway system includes a control unit that generates a pseudo transmission path failure in the station node, and a failure in an arbitrary station node causes a failure between the highway monitoring device and each station node. When normal communication is disrupted, the highway monitoring device searches for and detects a faulty station node, and generates a pseudo transmission path fault in the station node before the faulty station node according to instructions from the highway monitoring device to transmit the relevant transmission. The road failure is sequentially transmitted to the downstream station nodes, the transmission path is switched to the transmission path of another system at the failed station node and subsequent station nodes, and the highway monitoring device and the station node downstream from the failed station node are connected. An inter-node communication failure handling method characterized by being configured to enable communication between nodes.
JP58154698A 1983-08-24 1983-08-24 Method for processing inter-node communication fault Pending JPS6046636A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP58154698A JPS6046636A (en) 1983-08-24 1983-08-24 Method for processing inter-node communication fault

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP58154698A JPS6046636A (en) 1983-08-24 1983-08-24 Method for processing inter-node communication fault

Publications (1)

Publication Number Publication Date
JPS6046636A true JPS6046636A (en) 1985-03-13

Family

ID=15589987

Family Applications (1)

Application Number Title Priority Date Filing Date
JP58154698A Pending JPS6046636A (en) 1983-08-24 1983-08-24 Method for processing inter-node communication fault

Country Status (1)

Country Link
JP (1) JPS6046636A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5307353A (en) * 1990-05-09 1994-04-26 Fujitsu Limited Fault recovery system of a ring network

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5307353A (en) * 1990-05-09 1994-04-26 Fujitsu Limited Fault recovery system of a ring network
USRE37401E1 (en) 1990-05-09 2001-10-02 Fujitsu Limited Fault recovery system of a ring network

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