JP2745583B2 - Communication line switching method - Google Patents
Communication line switching methodInfo
- Publication number
- JP2745583B2 JP2745583B2 JP63276430A JP27643088A JP2745583B2 JP 2745583 B2 JP2745583 B2 JP 2745583B2 JP 63276430 A JP63276430 A JP 63276430A JP 27643088 A JP27643088 A JP 27643088A JP 2745583 B2 JP2745583 B2 JP 2745583B2
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- Prior art keywords
- data
- line
- channel
- modem
- sub
- Prior art date
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- 238000004891 communication Methods 0.000 title claims description 16
- 238000000034 method Methods 0.000 title claims description 7
- 230000005540 biological transmission Effects 0.000 claims description 14
- 239000000284 extract Substances 0.000 claims description 3
- 238000012360 testing method Methods 0.000 claims description 3
- 238000012423 maintenance Methods 0.000 description 5
- 238000001514 detection method Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000012544 monitoring process Methods 0.000 description 2
- 230000008054 signal transmission Effects 0.000 description 1
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Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は通信回線切替方式に関し、特に変復調装置間
の通信回線を専用線から公衆回線に切替える場合の通信
回線切替方式に関する。Description: TECHNICAL FIELD The present invention relates to a communication line switching system, and more particularly to a communication line switching system in a case where a communication line between modems is switched from a dedicated line to a public line.
〔従来の技術〕 従来、この種の通信回線切替方式は、対向している２
台の変復調装置間が専用線を介して通信を行っている構
成において、専用線に障害が生じた場合、専用線から公
衆回線へ通信回線を切替えるためには、変復調装置と専
用線間に予め接続しておいた通信回線切替方式を保守者
が操作し、切替える方法がとられていた。また専用線を
公衆回線を切り替える時は専用線の送信ライン，受信ラ
インのどちらに障害があるか分からないことが多いた
め、送／受信ラインを一対として公衆回線に切替えてい
た。[Prior Art] Conventionally, this type of communication line switching system has two
When a failure occurs in the dedicated line in a configuration in which communication is performed between the two modems via a dedicated line, in order to switch the communication line from the dedicated line to the public line, the communication between the modem and the dedicated line must be performed in advance. A method has been adopted in which a maintenance person operates and switches the communication line switching method that has been connected. Further, when switching the dedicated line to the public line, it is often not known whether the transmission line or the reception line of the dedicated line has a failure, and therefore, the transmission / reception line is switched to the public line as a pair.
上述した従来の通信回線切替方式は、専用線を障害に
より公衆回線に切替えたい場合は、保守者が専用線に障
害が発生した事を知った後、通信回線切替装置が設置さ
れている場所まで行き、通信回線の切替作業を人為的に
行わなければならないようになっているので、障害発生
から回線切替完了までに時間がかかるという欠点があ
る。又、専用線の送信ライン，受信ラインのどちらに障
害があったかが分からず、一方のラインのみの回線切替
で済むところを両ラインの回線切替をしてしまうので、
公衆回線の使用料金が２倍かかるという欠点がある。In the conventional communication line switching method described above, when a dedicated line is to be switched to a public line due to a failure, after the maintenance person knows that a failure has occurred in the dedicated line, the maintenance line is switched to the place where the communication line switching device is installed. In such a case, it is necessary to perform the switching operation of the communication line artificially, so that it takes time from the occurrence of a failure to the completion of the line switching. Further, it is not known whether the transmission line or the reception line of the dedicated line has a fault, and the line switching of both lines is performed where only the line switching of one line is sufficient.
There is a disadvantage that the usage fee of the public line is doubled.
本発明の通信回線切替方式は、第１の変復調装置が専
用線を介して第２の変復調装置とを接続し、前記第１及
び第２の変復調装置のそれぞれにはデータチャネルとは
周波数帯域を異にする副チャネルによって試験のデータ
を変調して送出する副チャネル変調部と、受信データか
ら前記副チャネルのデータのみを取り出すフィルタ部
と、前記副チャネルのデータを復調する副チャネル復調
部とを備え、前記第１の変復調装置（又は前記第２の変
復調装置）が送信ラインから前記副チャネルで第１デー
タを前記第２の変復調装置（又は前記第１の変復調装
置）に送出し続けて、前記第２の変復調装置（又は前記
第１の変復調装置）が前記副チャネル復調部で前記第１
のデータを受信した場合には前記第１のデータを、前記
第１のデータが受信できない場合には第２のデータを前
記第２の変復調装置（又は前記第１の変復調装置）が送
信ラインから前記副チャネルで送出する送出手段を有
し、また、前記第１の変復調装置（又は前記第２の変復
調装置）は前記副チャネル復調部で前記第２のデータを
受信した場合には送信ラインを前記専用線から公衆回線
に切替え、何等データを受信しない場合には受信ライン
を前記専用線から前記公衆回線に切替えた後に前記第２
のデータを受信した場合に前記送信ラインを前記専用線
から前記公衆回線に切替える切替手段を有している。In the communication line switching system of the present invention, a first modem connects to a second modem via a dedicated line, and each of the first and second modems has a data channel and a frequency band. A sub-channel modulation unit that modulates test data with a different sub-channel and transmits the data, a filter unit that extracts only the sub-channel data from received data, and a sub-channel demodulation unit that demodulates the sub-channel data. The first modem (or the second modem) continuously sends first data from the transmission line to the second modem (or the first modem) on the sub-channel, The second modulation / demodulation device (or the first modulation / demodulation device) is used by the sub-channel demodulation unit for the first modulation / demodulation unit.
When the first data is received, the first data is transmitted. When the first data is not received, the second data is transmitted from the transmission line by the second modem (or the first modem). The sub-channel demodulator includes a transmitting unit that transmits the sub-channel, and the first modem (or the second modem) sets a transmission line when the sub-channel demodulator receives the second data. When the dedicated line is switched to the public line and no data is received, the reception line is switched from the dedicated line to the public line before the second line.
And switching means for switching the transmission line from the dedicated line to the public line when the data is received.
次に、本発明の実施例について図面を参照して説明す
る。Next, embodiments of the present invention will be described with reference to the drawings.
第１図は本発明の一実施例を示す機能ブロック図であ
る。FIG. 1 is a functional block diagram showing one embodiment of the present invention.
第１図において、本実施例は、変復調装置１が専用線
7,8を介して変復調装置２と接続し、変復調装置１内に
はデータチャネル変調部10と、データチャネル復調部11
と、データチャネルとは周波数帯域を異にする副チャネ
ル変調部12と、受信データから副チャネルデータのみを
取り出すフィルタ部13と、副チャネルデータを復調する
副チャネル復調部14と、公衆回線3,4からの変復調装置
２に対して電話をかけるための選択信号送出部15と、選
択信号送出部15からの選択信号を公衆回線3,4のどちら
かに送出すかを切替えるスイッチ部（以下SWと記す）22
と、公衆回線3,4を変復調装置１内部に接続するための
回線接続部16,17と、専用線7,8から公衆回線3,4の接続
に切替えるためのSW23,40と、上記各部，各SWを制御す
る制御部24とを有し、変復調装置２内にはデータチャネ
ル変調部25と、データチャネル復調部26と、データチャ
ネルとは周波数帯域を異にする副チャネル変調部27と、
受信データから副チャネルデータのみを取り出すフィル
タ部28と、副チャネルデータを復調する副チャネル復調
部29と、公衆回線5,6からの呼出信号を検出するための
呼出信号検出部30と、公衆回線5,6を変復調装置２内部
に接続するための回線接続部31,32と、専用線7,8から公
衆回線5,6に切替えるためのSW37,38と、上記各部，各ス
イッチを制御する制御部39とを有して構成している。In FIG. 1, in this embodiment, a modem 1 is a dedicated line.
The modem is connected to the modem 2 via 7 and 8, and the data channel modulator 10 and the data channel demodulator 11 are provided in the modem 1.
And a sub-channel modulator 12 having a different frequency band from the data channel, a filter 13 for extracting only the sub-channel data from the received data, a sub-channel demodulator 14 for demodulating the sub-channel data, and a public line 3, And a switch unit (hereinafter referred to as SW) for selecting whether to transmit the selection signal from the selection signal transmission unit 15 to one of the public lines 3 and 4. Write down) 22
Line connection units 16 and 17 for connecting the public lines 3 and 4 inside the modem 1, SW23 and 40 for switching from the dedicated lines 7 and 8 to the connection of the public lines 3 and 4, A data channel modulation unit 25, a data channel demodulation unit 26, a sub-channel modulation unit 27 having a frequency band different from that of the data channel, and a control unit 24 for controlling each SW.
A filter unit 28 for extracting only the sub-channel data from the received data, a sub-channel demodulation unit 29 for demodulating the sub-channel data, a paging signal detection unit 30 for detecting a paging signal from the public lines 5 and 6, and a public line Line connection units 31 and 32 for connecting 5,6 inside the modem 2, SW37,38 for switching from dedicated lines 7,8 to public lines 5,6, and control for controlling the above units and switches And a part 39.
尚、変復調装置１は公衆回線3,4及び専用線7,8に接続
するためトランス（以下Ｔと記す）18,19,20,21を有
し、同様に変復調装置２は公衆回線5,6及び専用線7,8に
接続するためのT33,34,35,36を有している。The modem 1 has transformers (hereinafter, referred to as T) 18, 19, 20, 21 for connection to the public lines 3, 4 and the dedicated lines 7, 8, and the modem 2 similarly has the public lines 5, 6 And T33, 34, 35, and 36 for connection to the dedicated lines 7, 8.
次に、上述の構成において、変復調装置１が接続した
専用線7,8に障害が発生した場合に、公衆回線3,4,5,6に
より変復調装置２との接続に切替える動作について説明
する。Next, the operation of switching to the connection with the modem 2 via the public lines 3, 4, 5, and 6 when a failure occurs in the dedicated lines 7, 8 connected to the modem 1 in the above configuration will be described.
変復調装置１の制御部24はSW40を専用線７側に接続
し、SW23を専用線８側に接続し、回線接続部16,17をT1
8,19に接続しない状態としておく。The control unit 24 of the modem 1 connects the SW 40 to the dedicated line 7 side, connects the SW 23 to the dedicated line 8 side, and connects the line connecting units 16 and 17 to T1.
Leave unconnected to 8,19.
変復調装置２の制御部39はSW37を専用線７側に接続し
SW38を専用線８側に接続し、回線接続部31,32を呼出信
号検出部30に接続させた状態としておく。The control unit 39 of the modem 2 connects the SW 37 to the dedicated line 7 side.
The SW 38 is connected to the dedicated line 8 and the line connection units 31 and 32 are connected to the call signal detection unit 30.
変復調装置１では制御部24が副チャネル変調部12から
第１のデータを専用線７を介して変復調装置２に対して
送出し続ける。又、専用線８から受信したデータからフ
ィルタ部13で副チャネルのみを取り出し、副チャネル変
調部14から復調したデータが第１のデータであるか、第
２のデータであるか、全くデータを受信しないかの監視
を行っている。In the modem 1, the controller 24 continues to transmit the first data from the sub-channel modulator 12 to the modem 2 via the dedicated line 7. Also, only the sub-channel is extracted by the filter unit 13 from the data received from the dedicated line 8, and whether the data demodulated from the sub-channel modulation unit 14 is the first data, the second data, or We are monitoring whether there is any.
変復調装置２では制御部39が専用線７から受信したデ
ータからフィルタ部28で副チャネルのみを取り出し、副
チャネル復調部29から復調したデータが第１のデータで
あるが、データを受信しないかの監視を行っており、第
１のデータを受信した場合には副チャネル変調部27から
専用線８を介して第１のデータを送出し、データを受信
しない場合には第２のデータを送出する。又、公衆回線
5,6で電話の呼出しがないかを呼出信号検出部30によっ
て行う。In the modem 2, the control unit 39 extracts only the sub-channel from the data received from the dedicated line 7 by the filter unit 28, and the data demodulated from the sub-channel demodulation unit 29 is the first data. Monitoring is performed. When the first data is received, the first data is transmitted from the sub-channel modulator 27 via the dedicated line 8, and when the data is not received, the second data is transmitted. . In addition, public line
In steps 5 and 6, the call signal detecting unit 30 checks whether there is a telephone call.
上述の方法によって変復調装置１では第１のデータを
受信した場合は専用線7,8が正常であるものと認識す
る。第２のデータを受信した場合は専用線７に障害が発
生したものと認識し、あらかじめ設定された変復調装置
２の受信ライン側として接続された公衆回線５の電話番
号を送出するためSW22をT18側に接続し、選択信号送出
部15がダイヤル信号を送出する。変復調装置２では呼出
信号検出部30が呼出信号を検出すると、制御部39はSW37
を専用線７側から公衆回線５側へと切替える。変復調装
置１においても制御部24はSW40を専用線７側から公衆回
線３側へと切替える。According to the above-described method, when the first data is received, the modem 1 recognizes that the dedicated lines 7 and 8 are normal. When the second data is received, it is recognized that a failure has occurred in the dedicated line 7, and the SW22 is set to T18 for transmitting the telephone number of the public line 5 connected as a preset receiving line side of the modem 2. And the selection signal transmitting unit 15 transmits a dial signal. In the modem 2, when the paging signal detection unit 30 detects the paging signal, the control unit 39 switches to the SW37.
Is switched from the dedicated line 7 side to the public line 5 side. Also in the modem 1, the control unit 24 switches the SW 40 from the dedicated line 7 side to the public line 3 side.
上述の切替え動作によって変復調装置1,2間の専用線
７の接続を公衆回線3,5の接続に切替えることができ
る。By the switching operation described above, the connection of the dedicated line 7 between the modems 1 and 2 can be switched to the connection of the public lines 3 and 5.
変復調装置２が第1,第２のデータを受信しない場合に
は、まず、専用線８に障害が発生したことが分かるが、
専用線７にも障害が発生していることが考えられるた
め、まず、上述した方法と同様に変復調装置1,2間の専
用線８の接続を公衆回線4,6の接続に切替え、副チャネ
ル復調部14にて受信したデータを監視し、第１のデータ
を受信すれば専用線７には正常であるものと認識し、第
２のデータを受信すれば専用線７にも障害が発生したも
のと認識し、前述した方法により変復調装置1,2間の専
用線７の接続を公衆回線3,5の接続に切替える。When the modem 2 does not receive the first and second data, first, it can be seen that a failure has occurred in the dedicated line 8,
Since it is conceivable that a failure has also occurred in the leased line 7, first, the connection of the leased line 8 between the modems 1 and 2 is switched to the connection of the public lines 4 and 6 in the same manner as described above, and The demodulation unit 14 monitors the received data, and if the first data is received, it is recognized that the dedicated line 7 is normal, and if the second data is received, the dedicated line 7 also fails. The connection of the dedicated line 7 between the modems 1 and 2 is switched to the connection of the public lines 3 and 5 by the method described above.
以上説明したように、変復調装置１は専用線7,8の障
害が発生した場合に公衆回線3,4,5,6による変復調装置
２との接続を自動的に切替えることが可能となる。As described above, the modem 1 can automatically switch the connection to the modem 2 via the public lines 3, 4, 5, and 6 when the failure of the dedicated lines 7, 8 occurs.
以上説明したように本発明は、第１及び第２の変復調
装置が専用線を介してデータチャネルで通常のデータ通
信を行っているときに、相対向する変復調装置の一方に
おいて専用線の送信ライン、受信ラインの障害を副チャ
ネルによって試験用のデータ（第１及び第２のデータ）
を送出手段で送出して監視し、障害が発生したならば、
自動的に専用線を公衆回線に切替える切替手段を有する
ことにより、従来の様に専用線に障害が発生した場合、
保守者が通信回線切替装置の設置された場所まで行き、
専用線から公衆回線に切替える必要がなくなり、又、専
用線の送信ライン、受信ラインのどちらに障害が発生し
たかを保守者が調査することなく障害のあったラインを
専用線から公衆回線に切替えることが可能となるため公
衆回線を効率よく経済的に使用することができる効果が
ある。As described above, according to the present invention, when the first and second modems perform normal data communication on the data channel via the dedicated line, the transmission line of the dedicated line is used in one of the opposite modems. And test data (first and second data) for detecting a fault in the receiving line by the sub-channel
Is sent by the sending means and monitored, and if a failure occurs,
By having switching means to automatically switch the dedicated line to the public line, if a failure occurs in the dedicated line as before,
The maintenance person goes to the place where the communication line switching device is installed,
There is no need to switch from a dedicated line to a public line, and a failed line can be switched from a dedicated line to a public line without a maintenance person investigating whether a failure has occurred on the transmission line or the reception line of the dedicated line. This makes it possible to use the public line efficiently and economically.
第１図は本発明の一実施例を示す機能ブロック図であ
る。 1,2……変復調装置、3,4,5,6……公衆回線、7,8……専
用線、9,……公衆網、10,25……データチャネル変調
部、11,26……データチャネル復調部、12,27……副チャ
ネル変調部、13,28……フィルタ部、14,29……副チャネ
ル復調部、15……選択信号送出部、16,17…,31,32……
回線接続部、18,19,20,21……トランス（Ｔ）、22,23,3
7,38,40……スイッチ（SW）、24,39……制御部。FIG. 1 is a functional block diagram showing one embodiment of the present invention. 1,2 ... Modulator / demodulator, 3,4,5,6 ... Public line, 7,8 ... Dedicated line, 9, ... Public network, 10,25 ... Data channel modulator, 11,26 ... Data channel demodulators, 12, 27 ... sub-channel modulators, 13, 28 ... filter units, 14, 29 ... sub-channel demodulators, 15 ... selection signal transmitters, 16, 17, ..., 31, 32 ... …
Line connection part, 18,19,20,21 ... Transformer (T), 22,23,3
7, 38, 40: Switch (SW), 24, 39: Control unit.
Claims (1)
変復調装置と接続し、前記第１及び第２の変復調装置の
それぞれにはデータチャネルとは周波数帯域を異にする
副チャネルによって試験のデータを変調して送出する副
チャネル変調部と、受信データから前記副チャネルのデ
ータのみを取り出すフィルタ部と、前記副チャネルのデ
ータを復調する副チャネル復調部とを備え、前記第１の
変復調装置（又は前記第２の変復調装置）が送信ライン
から前記副チャネルで第１データを前記第２の変復調装
置（又は前記第１の変復調装置）に送出し続けて、前記
第２の変復調装置（又は前記第１の変復調装置）が前記
副チャネル復調部で前記第１のデータを受信した場合に
は前記第１のデータを、前記第１のデータが受信できな
い場合には第２のデータを前記第２の変復調装置（又は
前記第１の変復調装置）が送信ラインから前記副チャネ
ルで送出する送出手段を有し、また、前記第１の変復調
装置（又は前記第２の変復調装置）は前記副チャネル復
調部で前記第２のデータを受信した場合には送信ライン
を前記専用線から公衆回線に切替え、何等データを受信
しない場合には受信ラインを前記専用線から前記公衆回
線に切替えた後に前記第２のデータを受信した場合に前
記送信ラインを前記専用線から前記公衆回線に切替える
切替手段を有することを特徴とする通信回線切替方式。1. A first modulation / demodulation device is connected to a second modulation / demodulation device via a dedicated line, and each of the first and second modulation / demodulation devices has a sub-channel having a frequency band different from that of a data channel. A sub-channel modulator that modulates and transmits test data according to the first data, a filter that extracts only the data of the sub-channel from the received data, and a sub-channel demodulator that demodulates the data of the sub-channel. And the second modem (or the second modem) continuously sends the first data to the second modem (or the first modem) from the transmission line on the sub-channel by the second modem. If the device (or the first modem) receives the first data in the sub-channel demodulation unit, the first data is used. If the first data cannot be received, the second data is used. The second modulator / demodulator (or the first modulator / demodulator) has transmission means for transmitting data from the transmission line via the sub-channel, and the first modem (or the second modem). ) Switches the transmission line from the dedicated line to the public line when the second data is received by the sub-channel demodulation unit, and switches the reception line from the dedicated line to the public line when no data is received. A communication line switching method, comprising: switching means for switching the transmission line from the leased line to the public line when the second data is received after the switching.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63276430A JP2745583B2 (en) | 1988-10-31 | 1988-10-31 | Communication line switching method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63276430A JP2745583B2 (en) | 1988-10-31 | 1988-10-31 | Communication line switching method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02122755A JPH02122755A (en) | 1990-05-10 |
| JP2745583B2 true JP2745583B2 (en) | 1998-04-28 |
Family
ID=17569305
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63276430A Expired - Lifetime JP2745583B2 (en) | 1988-10-31 | 1988-10-31 | Communication line switching method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2745583B2 (en) |
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| US10293421B2 (en) * | 2016-09-15 | 2019-05-21 | Dustless Depot, Llc | Circular saw dust collection shroud |
| US11123839B2 (en) | 2018-10-23 | 2021-09-21 | Dustless Depot Llc | Grinder dust shroud with input shaft gasket and adjustable mounting mechanism |
| USD908149S1 (en) | 2018-10-23 | 2021-01-19 | Dustless Depot Llc | Angle grinder dust shroud with variable position slots for mounting brackets |
| US11273505B2 (en) | 2019-03-27 | 2022-03-15 | Dustless Depot, Llc | Circular saw dust collection shroud |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6239937A (en) * | 1985-08-15 | 1987-02-20 | Nec Corp | Communication line switching unit |
| JPS62241452A (en) * | 1986-04-14 | 1987-10-22 | Oki Electric Ind Co Ltd | Circuit test system |
-
1988
- 1988-10-31 JP JP63276430A patent/JP2745583B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02122755A (en) | 1990-05-10 |
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