JPH0318378B2 - - Google Patents
Info
- Publication number
- JPH0318378B2 JPH0318378B2 JP56139715A JP13971581A JPH0318378B2 JP H0318378 B2 JPH0318378 B2 JP H0318378B2 JP 56139715 A JP56139715 A JP 56139715A JP 13971581 A JP13971581 A JP 13971581A JP H0318378 B2 JPH0318378 B2 JP H0318378B2
- Authority
- JP
- Japan
- Prior art keywords
- transmission line
- data
- transmission
- circuit
- station
- 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.)
- Expired - Lifetime
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Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L1/00—Arrangements for detecting or preventing errors in the information received
- H04L1/22—Arrangements for detecting or preventing errors in the information received using redundant apparatus to increase reliability
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L12/00—Data switching networks
- H04L12/28—Data switching networks characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks]
- H04L12/42—Loop networks
- H04L12/437—Ring fault isolation or reconfiguration
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Detection And Prevention Of Errors In Transmission (AREA)
- Small-Scale Networks (AREA)
Description
【発明の詳細な説明】
本発明は、ループ伝送システムに係り、特に予
備伝送路の識別と、現用伝送路と予備伝送路の切
り替えを行なう時の方式に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a loop transmission system, and particularly to a method for identifying a protection transmission path and switching between a working transmission path and a protection transmission path.
従来、予備伝送路を有するようなループ伝送シ
ステムにおいて、現用伝送路に障害が発生した場
合、予備伝送路に切り替えようとする方式あるい
は予備伝送路がいずれの伝送路であるかの識別を
行なう方式として、(1)データ伝送路以外に制御信
号線を布設し、ループ伝送システムの監視とシス
テム切り替え制御等を行なう制御局は、この制御
信号線で現用／予備の識別信号または切り替え信
号を各端局に送出することにより、予備伝送路の
識別を行なつたり伝送路切り替えを行なう方式、
または(2)各端局が個々に障害発生を検知し、予備
伝送路に切り替える方式、あるいは(3)特定の切り
替えデータを制御局が正常な伝送路を用いて転送
し、各端局が該データを受信したとき予備伝送路
に切り替える、という方式が考えられてきた。 Conventionally, in a loop transmission system that has a backup transmission line, when a fault occurs in the working transmission line, a method is used to switch to the backup transmission line or to identify which transmission line is the backup transmission line. (1) A control signal line is installed in addition to the data transmission line, and the control station that monitors the loop transmission system and controls system switching uses this control signal line to send the working/standby identification signal or switching signal to each end. A method for identifying backup transmission lines and switching transmission lines by transmitting data to stations;
or (2) a method in which each terminal station individually detects the occurrence of a failure and switches to a backup transmission path, or (3) a control station transfers specific switching data using a normal transmission path, and each terminal station A method of switching to a backup transmission line when data is received has been considered.
しかし、(1)の方式は、別の伝送路が必要とな
り、かつこの伝送路に付随した制御回路が別途必
要となり高価なものとなる。また、(2)の方式は、
各端局が独自の判断で切り替えるため、切り替え
タイミングが異なり、制御局での管理が困難であ
る。また、(3)の方式は、現用伝送路、予備伝送路
ともにデータ授受機能を有さなければならず、高
価なものとなるという欠点があつた。 However, the method (1) requires another transmission path and a separate control circuit associated with this transmission path, making it expensive. In addition, method (2) is
Since each terminal station switches based on its own judgment, the switching timing differs, making management by the control station difficult. Furthermore, the method (3) has the disadvantage that both the working transmission line and the backup transmission line must have a data exchange function, making it expensive.
そこで本発明の目的とするところは、前述の如
き従来技術の欠点を除去すること、つまり、伝送
路切り替えが予備／現用伝送路表示のため、デー
タ伝送路以外の制御線を設けることなく、制御局
でのデータ伝送路管理が容易で、安価にループ伝
送路切り替えまたは現用／予備伝送路表示を行な
うことが可能なループ伝送システムを提供するこ
とにある。 Therefore, it is an object of the present invention to eliminate the drawbacks of the prior art as described above. In other words, since the transmission path switching is for displaying the backup/working transmission path, it is possible to control the transmission path without providing any control line other than the data transmission path. It is an object of the present invention to provide a loop transmission system in which data transmission path management at a station is easy and loop transmission path switching or working/protection transmission path display can be performed at low cost.
すなわち、本発明の特徴は、現用／予備の２系
統からなるループ伝送システムにおいて、制御局
は、予備となつている伝送路系統に対して特定の
繰返しパターンデータの送出／送出停止／機能を
有し、各端局は、この特定パターンデータの検出
機能を具備することによつて予備伝送路がいずれ
かであるかを識別し、現用伝送路が障害となつた
とき、制御局は特定繰返しパターンデータの送出
を停止することによつて、各端局に予備伝送路へ
の切り替えを行なわせようとすることにある。 In other words, the feature of the present invention is that in a loop transmission system consisting of two lines, a working line and a standby line, a control station can transmit/stop sending/function a specific repeating pattern data to the standby transmission line line. By being equipped with a function to detect this specific pattern data, each terminal station can identify which one is the backup transmission path, and when the working transmission path becomes a failure, the control station detects the specific repeating pattern. The purpose is to have each terminal station switch to a backup transmission line by stopping data transmission.
以下、本発明の一実施例を第１図、第２図によ
り説明する。 An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.
第１図は、本発明のループ伝送システムの構成
図で、１は制御局、２−１〜２−６は端局、３は
Ａ伝送路、４はＢ伝送路で、この２本の伝送路に
よつてループ状に接続されている。また、Ａ伝送
路３と、Ｂ伝送路４のいずれか一方が現用伝送路
で、他方は予備伝送路となつており、一方に障害
が発生しても他方によつて運転する構成となつて
いる。 FIG. 1 is a configuration diagram of a loop transmission system according to the present invention, in which 1 is a control station, 2-1 to 2-6 are terminal stations, 3 is an A transmission line, and 4 is a B transmission line. They are connected in a loop by channels. In addition, one of the A transmission line 3 and the B transmission line 4 is a working transmission line, and the other is a backup transmission line, so that even if a failure occurs in one, the other is used for operation. There is.
第２図は、制御局１および端局２−１〜２−６
の各々における回路構成を示すブロツク図であ
る。 Figure 2 shows control station 1 and terminal stations 2-1 to 2-6.
FIG. 3 is a block diagram showing the circuit configuration in each of the circuits.
Ａ伝送路３、Ｂ伝送路４は、図に示すように復
調回路６−１，６−２に各々接続され、復調回路
６−１，６−２で復調されたデータ信号は、スイ
ツチ回路１０に接続される。スイツチ回路１０
は、現用伝送路となつている側の復調回路６−１
又は６−２からのデータ信号をデータ制御回路１
２に転送するためのスイツチと、データ制御回路
１２から送られてくるデータ信号を現用伝送路と
なつている側の変調回路５−１又は５−２に送出
するためのスイツチと、制御局１の場合には予備
伝送路となつている側の伝送路３又は４に対し特
定の繰返しパターンデータであるドツトパターン
データ（1010……）を送出するためドツトパター
ン発生回路１１からの信号を送出するためのスイ
ツチ、から成つている。 The A transmission line 3 and the B transmission line 4 are connected to demodulation circuits 6-1 and 6-2, respectively, as shown in the figure, and the data signals demodulated by the demodulation circuits 6-1 and 6-2 are sent to a switch circuit 10. connected to. switch circuit 10
is the demodulation circuit 6-1 on the side that is the working transmission line.
Or the data signal from 6-2 is sent to the data control circuit 1.
a switch for transmitting the data signal sent from the data control circuit 12 to the modulation circuit 5-1 or 5-2 on the side that is the active transmission path; In this case, a signal is sent from the dot pattern generation circuit 11 to send dot pattern data (1010...), which is specific repeating pattern data, to the transmission line 3 or 4 serving as the backup transmission line. It consists of a switch for
また、端局２−１〜２−６においては、スイツ
チ回路１０は、予備伝送路となつている側の復調
回路６−１又は６−２のデータをそのまま変調回
路５−１又は５−２に伝送する。現用伝送路にあ
つては、自局がデータを送出するとき以外は、復
調回路６−１又は６−２のデータを受信すると同
時にそのまま変調回路５−１又は５−２に伝達す
る機能を有しており、これら全てのスイツチ動作
は制御回路９の指令により動作する。 Further, in the terminal stations 2-1 to 2-6, the switch circuit 10 transfers the data from the demodulation circuit 6-1 or 6-2 on the side serving as the backup transmission line directly to the modulation circuit 5-1 or 5-2. to be transmitted. In the case of the current transmission line, except when the own station transmits data, it has a function of receiving data from the demodulation circuit 6-1 or 6-2 and transmitting it as is to the modulation circuit 5-1 or 5-2 at the same time. All these switch operations are performed by commands from the control circuit 9.
さらに、スイツチ回路１０は、変調回路５−
１，５−２、復調回路６−１，６−２以外の回路
すべてが非動作状態、すなわち該端局が非データ
伝送モードの時、復調回路６−１，６−２と変調
回路５−１，５−２を各々直結し、該端局をデー
タの受信を全く行なわない中継機能のみとなるよ
うな接続形態とする、いわゆるバイパス機能をも
有している。 Further, the switch circuit 10 includes a modulation circuit 5-
1, 5-2, when all circuits other than the demodulation circuits 6-1 and 6-2 are in a non-operating state, that is, when the terminal station is in a non-data transmission mode, the demodulation circuits 6-1 and 6-2 and the modulation circuit 5- It also has a so-called bypass function, in which terminal stations 1 and 5-2 are directly connected to each other, and the terminal station functions only as a relay function without receiving any data.
７はドツトパターン検出回路で、ドツトパター
ンデータを所定時間継続して受信していることを
検出し、制御回路９に伝達する機能を有してい
る。ドツトパターン検出回路７は、通常の電文中
のデータとの区別を行なうため、電文長に比べ充
分長い時間継続してドツトパターンデータが受信
されていることを検出したら、出力信号を発生す
る。 A dot pattern detection circuit 7 has a function of detecting that dot pattern data is continuously received for a predetermined period of time and transmitting the detected data to the control circuit 9. The dot pattern detection circuit 7 generates an output signal when it detects that dot pattern data has been received for a sufficiently long time compared to the length of the message in order to distinguish it from data in a normal message.
８は障害検出回路で、復調回路６−１，６−２
によつて抽出されたデータに同期したタイミング
信号の正常性をチエツクし、異常があつた場合、
障害検出信号をオンとし、制御回路９に伝える機
能を有している。 8 is a failure detection circuit, and demodulation circuits 6-1 and 6-2
Check the normality of the timing signal synchronized with the data extracted by
It has a function of turning on a failure detection signal and transmitting it to the control circuit 9.
１１はドツトパターンデータの発生回路で、制
御局１にしか存在しない。ドツトパターンデータ
の送出／送出停止は、制御回路９によつて制御さ
れる。 Reference numeral 11 denotes a dot pattern data generation circuit, which exists only in the control station 1. Sending/stopping of the dot pattern data is controlled by a control circuit 9.
１２はデータの送受信を行なうデータ制御回路
であるが、本発明には直接関係しないので説明を
省略する。 Reference numeral 12 denotes a data control circuit for transmitting and receiving data, but its explanation will be omitted since it is not directly related to the present invention.
次に本システムの動作について説明する。ま
ず、端局２−１〜２−６のいずれかが非動作状態
にあつたが、動作状態となりループに参加しよう
とする場合の動作について述べる。 Next, the operation of this system will be explained. First, the operation will be described when one of the terminal stations 2-1 to 2-6 has been in an inactive state, but becomes active and attempts to participate in the loop.
これは、ある端局において保守作業完了に伴
い、通常運転に戻ろうとする場合や、該端局が他
端局の始業より遅れて始業をする場合等に行なわ
れるものである。 This is performed when a certain terminal station attempts to return to normal operation upon completion of maintenance work, or when the terminal station starts work later than the other terminal station.
この場合、始業命令が制御回路９に与えられる
と、制御回路９はＡ伝送路３、Ｂ伝送路４のいず
れが現用伝送路となつているかを判断するため
に、ドツトパターン検出回路７の出力信号を参照
する。このとき、ドツトパターンデータ受信中の
側の伝送路は予備伝送路であることを意味してい
るので、ドツトパターンデータ受信中でない側が
現用伝送路であると判断し、スイツチ回路１０に
対して、しかるべく接続し、データ制御回路１２
との通信を行なうよう指示する。このようにして
現用伝送路の判定を行なう。 In this case, when a start command is given to the control circuit 9, the control circuit 9 detects the output of the dot pattern detection circuit 7 in order to determine which of the A transmission line 3 and the B transmission line 4 is the active transmission line. Browse signals. At this time, since the transmission line on the side receiving dot pattern data is a backup transmission line, it is determined that the side on which dot pattern data is not being received is the working transmission line, and the switch circuit 10 Connect the data control circuit 12 accordingly.
Instruct to communicate with. In this way, the currently used transmission path is determined.
次に、現用となつていた伝送路で障害が発生し
たとき、予備伝送路に切り替える動作について述
べる。 Next, we will discuss the operation of switching to a protection transmission line when a failure occurs in the currently used transmission line.
仮に、Ａ伝送路３が現用伝送路となつている時
に、端局２−２と２−３間で障害が発生したもの
として説明する。 The following explanation assumes that a failure occurs between the terminal stations 2-2 and 2-3 while the A transmission line 3 is the working transmission line.
端局２−３は、障害検出回路８によつてＡ伝送
路３のタイミング信号異常を検知する。この時、
端局２−３がデータ送受信中であつた場合には、
データ送受信が中断される。しかし、予備伝送路
であるＢ伝送路４にはドツトパターンデータが送
出され続けているため、Ｂ伝送路４が依然として
予備伝送路となり、伝送路交替はしない。従つて
端局２−３では、Ａ伝送路３、Ｂ伝送路４の信号
をそのまま端局２−４に送る。そして端局２−４
〜２−６も同様に行なう。 The terminal station 2 - 3 detects a timing signal abnormality on the A transmission line 3 using the failure detection circuit 8 . At this time,
If terminal station 2-3 is transmitting and receiving data,
Data transmission/reception is interrupted. However, since the dot pattern data continues to be sent to the B transmission line 4, which is the backup transmission line, the B transmission line 4 remains the backup transmission line, and the transmission line is not replaced. Therefore, the terminal station 2-3 sends the signals on the A transmission line 3 and the B transmission line 4 as they are to the terminal station 2-4. and terminal station 2-4
- 2-6 are also carried out in the same manner.
制御局１で、端局２−４〜２−６と同様、障害
検知をすると、制御局１の制御回路９は、スイツ
チ回路１０を介しての変調回路５−１に対しＡ伝
送路３に対する変調動作の停止を指令すると共
に、ドツトパターン発生回路１１に対し、Ｂ伝送
路４に送出しているドツトパターンデータの送出
を停止するよう指令する。これによつて、端局２
−１，２−２は端局２−４〜２−６と同様、障害
検知を行なうが、さらに、Ｂ伝送路４側のドツト
パターンデータの送出停止が行なわれたことによ
つて、端局２−１〜２−６の制御回路９は、ドツ
トパターン検出回路７を介してドツトパターンデ
ータが検出されなくなつた事を知り、制御局１か
らループ伝送路交替指示が来たと判定し、Ｂ伝送
路４側に切り替えるようスイツチ回路１０に対し
指令し、ループ伝送路交替を行なう。 When the control station 1 detects a fault in the same manner as the terminal stations 2-4 to 2-6, the control circuit 9 of the control station 1 transmits the signal to the A transmission line 3 to the modulation circuit 5-1 via the switch circuit 10. It instructs to stop the modulation operation, and also instructs the dot pattern generation circuit 11 to stop sending out the dot pattern data being sent to the B transmission line 4. By this, terminal station 2
-1 and 2-2 perform failure detection in the same way as terminal stations 2-4 to 2-6, but in addition, because the transmission of dot pattern data on the B transmission line 4 side has been stopped, the terminal stations The control circuits 9 of 2-1 to 2-6 learn that the dot pattern data is no longer detected through the dot pattern detection circuit 7, and determine that a loop transmission line replacement instruction has been received from the control station 1. The switch circuit 10 is commanded to switch to the transmission line 4 side, and loop transmission line replacement is performed.
一方Ａ伝送路３は予備伝送路となり、障害対策
の実施の対象となる。 On the other hand, the A transmission line 3 becomes a backup transmission line and is subject to failure countermeasures.
なお、本実施例は一例にすぎず、特定繰返しパ
ターンデータはドツトパターンデータに限らず、
11001100……等、繰返し形のパターンデータ全て
を含むものである。また、障害検出回路８の障害
検知方法として、データに同期したタイミング信
号による方法について述べたが障害検知方法とし
ては、データの合理性チエツク、シーケンスチエ
ツク等があり、障害検知方法は１つの方法に限定
されるものではないことはいうまでもない。 Note that this embodiment is just an example, and the specific repeating pattern data is not limited to dot pattern data.
11001100..., etc., it includes all repeating pattern data. In addition, as a fault detection method for the fault detection circuit 8, a method using a timing signal synchronized with data has been described, but fault detection methods include a data rationality check, a sequence check, etc., and there is only one fault detection method. Needless to say, it is not limited.
以上の如き本発明によれば、次の効果が得られ
る。 According to the present invention as described above, the following effects can be obtained.
(1) データ伝送路を用いて全ての制御を行なうた
め、他の制御線を必要としない。(1) All control is performed using the data transmission line, so no other control lines are required.
(2) 予備伝送路表示として現用伝送路では使用し
ない特定の繰返しパターンデータを用いている
ので、特定のパターンデータの発生および検出
は、簡単なカウンタ回路とデコーダ回路を主と
した安価な回路で実現できる。(2) Since specific repeating pattern data that is not used in the active transmission line is used to indicate the backup transmission line, generation and detection of the specific pattern data can be done using inexpensive circuits mainly consisting of a simple counter circuit and a decoder circuit. realizable.
(3) 特定パターンデータ送出の制御が制御局にあ
るため、網内管理が一元化され、確実なループ
伝送路交替と網内管理が容易となる。(3) Since control of specific pattern data transmission is in the control station, network management is unified, and reliable loop transmission path replacement and network management are facilitated.
第１図は、本発明の一実施となるループ伝送シ
ステムの構成図、第２図は、第１図における制御
局および端局の各々における回路構成を示すブロ
ツク図である。
符号の説明、１…制御局、２−１〜２−６…端
局、３，４…伝送路、５−１，５−２…変調回
路、６−１，６−２…復調回路、７…ドツトパタ
ーン検出回路、８…障害検出回路、９…制御回
路、１０…スイツチ回路、１１…ドツトパターン
発生回路、１２…データ制御回路。
FIG. 1 is a block diagram of a loop transmission system embodying the present invention, and FIG. 2 is a block diagram showing the circuit configuration of each of the control station and terminal station in FIG. 1. Explanation of symbols, 1... Control station, 2-1 to 2-6... Terminal station, 3, 4... Transmission line, 5-1, 5-2... Modulation circuit, 6-1, 6-2... Demodulation circuit, 7 ... dot pattern detection circuit, 8 ... failure detection circuit, 9 ... control circuit, 10 ... switch circuit, 11 ... dot pattern generation circuit, 12 ... data control circuit.
Claims (1)
路によつてループを構成し、前記２系統のデータ
伝送路のうちの一方の伝送路が現用伝送路、他方
が予備伝送路であるループ伝送システムにおい
て、前記現用伝送路には、前記制御局又は前記各
端局が当該制御局又は当該端局以外の局へのデー
タを送出し、前記予備伝送路には、通常、前記制
御局が特定の繰返しパターンデータを送出し、前
記各端局は当該特定の繰返しパターンデータを検
出することによつて、前記２系統のデータ伝送路
のうちいずれが予備伝送路であるかを識別するこ
とを特徴とするループ伝送システム。 ２ 特許請求の範囲第１項記載のループ伝送シス
テムにおいて、前記各端局は、前記特定繰返しパ
ターンデータが検出されなくなつた時前記予備伝
送路を現用伝送路に切替ることによつて、ループ
伝送路交替を行うことを特徴とするループ伝送シ
ステム。[Scope of Claims] 1. A control station and one or more terminal stations form a loop using two data transmission lines, one of the two data transmission lines being a working transmission line and the other being a working transmission line. In a loop transmission system in which the control station or each terminal station sends data to a station other than the control station or the terminal station to the working transmission line, and the protection transmission line Usually, the control station sends out specific repeating pattern data, and each terminal station detects the specific repeating pattern data to determine which of the two data transmission lines is the backup transmission line. A loop transmission system characterized by identifying whether 2. In the loop transmission system according to claim 1, each of the terminal stations switches the protection transmission line to the working transmission line when the specific repeating pattern data is no longer detected, thereby transmitting the loop transmission line. A loop transmission system characterized by switching transmission lines.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13971581A JPS5842337A (en) | 1981-09-07 | 1981-09-07 | loop transmission system |
| US06/354,918 US4435704A (en) | 1981-03-13 | 1982-03-08 | Loop transmission system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13971581A JPS5842337A (en) | 1981-09-07 | 1981-09-07 | loop transmission system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5842337A JPS5842337A (en) | 1983-03-11 |
| JPH0318378B2 true JPH0318378B2 (en) | 1991-03-12 |
Family
ID=15251723
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13971581A Granted JPS5842337A (en) | 1981-03-13 | 1981-09-07 | loop transmission system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5842337A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6412737A (en) * | 1987-07-07 | 1989-01-17 | Nec Corp | Data transmission equipment |
| US4893763A (en) * | 1987-12-22 | 1990-01-16 | Roll Systems, Inc. | Roll support and feed apparatus |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5626189B2 (en) * | 1974-12-27 | 1981-06-17 | ||
| JPS5177017A (en) * | 1974-12-27 | 1976-07-03 | Fujitsu Ltd | DEETADENSOROKIRIKAE HOSHIKI |
-
1981
- 1981-09-07 JP JP13971581A patent/JPS5842337A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5842337A (en) | 1983-03-11 |
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