JPS59211351A - Loop transmission system - Google Patents

Abstract

PURPOSE:To change a loop constitution by remote control by forming an interface device and a transmission line in pair to obtain a module formation, and executing the cut-off of the interface device without interrupting communication. CONSTITUTION:An interface device I4 has an outgoing transmission line f3 and a return transmission line b3. A selecting circuit SW04 changes over selectively a signal line from a station device S4 and a transmission line from the interface device provided at the pre-stage in high speed. A selecting circuit SW14 selects switchingly the transmission line from the interface device provided at the post- stage and the signal line from the circuit SW04 in high speed. Then, station devices are increased or decreased through on-line without exerting any effect on the communication among other station devices.

Description

[Detailed Description of the Invention] [Technical Field to which the Invention Pertains] The present invention provides a loop transmission method in which a communication path is formed in a loop shape, in which the connection form between an interface device, a station device, and the transmission path can be changed without interrupting communication. This relates to a loop transmission method that can be changed.

[Description of prior art]

FIG. 1 shows the configuration of a conventional loop transmission system.

The interface devices If, 12.13.14 are connected to the station devices S1, S2, S3, and S4, respectively, and the interface devices 11 and I2, I2 and 13.13, and I4.14 and 11 are connected to the transmission path '1. 12.7
! 3.124. At this time, interface devices and station devices may be added,
To disconnect, -transform path β1~! 1 of the crows
The drawback was that system operation had to be temporarily interrupted in order to separate the books and reconfigure the loop.

To prevent this, it is possible to make the loops redundant so that even if one loop is disconnected, the other one will be used to eliminate communication interruptions, but this would require more hardware and be more expensive. There was a drawback.

[Purpose of the invention]

The present invention solves these drawbacks, and is capable of disconnecting the interface device without interrupting communication when adding or installing an interface device and a station device, or when a station device fails, and further enables disconnection of the interface device by remote control. An object of the present invention is to provide a loop transmission method that allows the loop configuration to be changed.

[Features of the invention]

The present invention provides a loop transmission method consisting of a transmission path, a station device, and an inkface device that connects the transmission path and the station device, in which the outgoing and return transmission paths are configured to pass together in the inkface device, and each ink In the face device, there is a first selection circuit that quickly switches and selects the transmission path from the front ink face device and the signal path from the station device, and the transmission path from the rear ink face device and the first selection circuit. A second selection circuit that switches and selects the signal path from the circuit at high speed is provided, and communication is interrupted when adding or installing an interface device or station device, or when disconnecting or reconnecting a station device in the event of a failure. The feature is that the interface device can be disconnected and connected without having to do so.

[Explanation based on examples]

FIG. 2 is a diagram showing the configuration of an ink face device according to an embodiment of the present invention. fx, I2 is the outgoing transmission line, bl,
b2 indicates a return transmission path, and both the outbound and return transmission paths pass through the interface device. C1, C2, C
3, C4 indicates a connector that connects the transmission path and the interface device.

S Wo and S wl are selection circuits that select transmission paths. The selection circuits SWo and SWI are constructed using semiconductor switch circuits so that communication signals can be switched at a sufficiently high speed. ml and m2 are transmission lines for exchanging signals with the station device.

FIG. 3 is a block diagram of an embodiment of the present invention. This is the second
The configuration of a loop transmission system to which the interface devices shown in the figure are connected is shown. 11.12.11-x, ■. , In+1
indicates an interface device, Sl, S2.5n-1,
Sn and Sn+1 indicate station devices. fx,
fn-t and fn are respectively the interface device 11
12, In-1 to I, , indicates the outgoing transmission path from In to In+1 direction, and bl, byl-1, t)++ are,
interface devices I2 to lx and In to l, respectively.
The return transmission path from l-1 and In+1 in the rn direction is shown.

C1x, C21, C12, etc. are configured so that both of these bidirectional transmission paths pass through each interface device.
C22・C42・C32, C1n-t, C2n-z
, C3n-1, C4n-1, C1n -C2ns C3
n,, C4n5 cl, n+1, C2n+t are connectors that connect the transmission line and the interface device. m12
, m22, m171-1% m 2 n-1%min
+1 and ff121+1 are transmission paths between the interface device and the station device.

In FIG. 3, interface devices 11 and In are interface devices that terminate the loop transmission system, and interface devices I2 to 11-i are interface devices that perform relaying using the loop transmission method. Interface device■. If +1 is added, it will be relayed by the interface device In, and the same I will be relayed by the interface device In. It will be turned around at +1. Also, the interface device ■. When you install
It will be turned back at the ink face device In-1.

FIG. 4, FIG. 5, and FIG. 6 are diagrams illustrating a method for adding station devices. The same symbols as in Fig. 1, Fig. 2, and Fig. 3 indicate the same parts, and CO4%Ct4s C2
4) C34% C05% Cz5s C26\
C3s indicates a connector. swol, 5W14, swo
5.5W15 indicates a selection circuit. k04, k14 are the contacts of the selection circuit swo4, mO, m14 are the selection circuit 5W1
4 contacts, k05 and k15 are the contacts of the selection circuit swo5,
m(,5,rn 15 c3M This is the contact point of the selection circuit 5W15.

FIG. 4 shows a case where the interface device 4 is the final stage interface device. In this case, the selection circuit SW
. , is the contact point k. , the station-specific signals are selected. Further, the selection circuit 5W14 selects the signal from the station device s4 through the contact mo4. Therefore, the signal from the outbound transmission path f3 passes through the station device s4 within the inkface device I4, and then is looped back to the return path.

Next, the case where the station device s5 is added in this state will be explained. First, the interface device I5 is added. This is shown in FIG. Connect the ink face device ■5 to the interface device ■→ using cables f4 and b4. At this time, the selection circuit 5Wo5 of the interface device I5 selects the signal from the station device S5, and the selection circuit 5Wts selects the signal from the station device S5. In this state, the electrical signal is still being looped back at the interface device (4).

Next, the station device S is connected to the interface device I5.
Connect 5. The selection circuit S is connected to the interface device I4.
When a switching signal is applied to select the signal from the transmission line b4 through the contact m14 of W□, the interface device 1
1<, the selection circuit SW 14 is switched accordingly.

This allows the interface device 11.12.13.14
．． A loop passing through 15 is created. In this state, as shown in FIG. 6, the selection circuit 5Wo5 is controlled to set the contact point 15 to k. 5, station device S5 is incorporated into the loop, and station device s5 is enabled to communicate with other station devices.

This switching signal can be generated within the interface device, or can be generated in one control station (not shown) and transmitted by some method to the corresponding interface device.

FIG. 7, FIG. 8, and FIG. 9 show a method of mounting the station device. FIG. 7 shows the state before the station device S5 and the interface device 5 are mounted. First, as shown in FIG. 8, the contact of the selection circuit 5Wo5 of the interface device I5 is switched to k by a switching signal. Switch from 5 to 15. As a result, the station device S5 is mounted. Next, the switching signal causes the interface device I to
The contact point of the selection circuit 5Wo4 of No. 4 is m. Switch from 4 to m14. As a result, the signal from the transmission line r3 passes through the station device S4, is turned back at the interface device I4, and is sent to the transmission line b3. As a result, the interface device I5 is mounted. Furthermore, connector C
34 and C24 are separated, as shown in FIG.
Installation of the station device s5 and the interface device I5 is completed.

FIG. 10 shows an example of disconnection of the station device when the station device fails. Reference character e is a signal line that conveys a failure of the station device S4 to the interface device 14.

When a failure occurs in the station device S4, a signal flows through the signal line e to the selection circuit 5Wo4 of the interface device I4, and the contact point k is connected. Switch from 4 to ki4. This results in
The faulty station device S4 can be disconnected from the loop transmission path without interrupting communications between other stations.

FIG. 11 is a more specific configuration diagram of the interface device. fa is the outbound transmission path from the front interface device, ba is the return transmission path to the front interface device, fb is the outbound transmission path to the rear interface device, and bb is the outbound transmission path from the rear interface device. This is the return transmission path. Cz, C2, C3, C4 are connectors, S Wo
, , SWl is a selection circuit. Each selection circuit S Wo
, SWl is configured using a semiconductor switch circuit so as to be able to perform sufficiently high-speed switching with respect to the communication speed.

AD is address detection circuit, SP is order expansion circuit, ES
is a fault information sending circuit. ml is an information line that brings information from the transmission path to the station, and m2 is an information line that brings information from the station to the transmission path. Also kl
o is a signal line for transmitting alarm information of the station to the interface device, and k6 is a signal line for transmitting restart information from the transmission route to the station. k1～5, kt, ks～
k14 is a signal line connecting each circuit or between a circuit and a transmission line. FIG. 12 shows an example of channel allocation on a transmission frame of a signal transmitted on a transmission path.

Automatic switching of the selection circuit by a signal from a transmission line will be explained using FIG. 11 and FIG. 12. It is now assumed that in the interface device (2), the selection circuit SWo selects the information m2 from the station, and the selection circuit SWL selects 14 as the return information line from the outgoing transmission line.

At this time, the first channel (I Cl
) to the address of this interface device ■, and the information line of the selection circuit S, W1 to the second channel (2CH).
An order to switch from 4 to bb is set and sent. The address detection circuit AD inputs the first channel (I C11) into the signal line through 1 and inputs the first channel (I C11) into the signal line.
The address information of CH) is compared with the address information of its own interface device, and when the two match, a signal g1 is sent to the order expansion circuit sp through signal line 3. The order development circuit SP takes in the second channel (2CH) from the transmission line fa through the information line 2, and upon receiving the signal g1, analyzes the information of the second channel (2CH) and converts the switching signal g2 of the selection circuit SW1 into a signal. Pass 4 on the line and output.

When the selection circuit SW1 receives the switching signal g2, it switches the information line to 1.
Switch from 4 to bb.

Also, fault information from the station equipment is sent to the signal line at 10
The address information and fault information of the interface device I are created here and sent to the third channel (3C11) via the signal line 8. In addition, in the event of a station equipment failure, the signal line
Information of 0 is transmitted to the signal line 12, the selection circuit SWo is switched to select the transmission path fa, and the station device is disconnected.

[Response]

Although the method of the present invention was conceived for a loop transmission line that interconnects a large number of digital switching devices, it can be implemented not only for switching devices but also for interconnecting various data communication devices. .

〔Effect of the invention〕

As explained above, in this embodiment, the inkface device and the transmission path are modularized as one set, so in the loop transmission method, station devices can be added or added online without affecting communication between other station devices. It can be installed. Furthermore, if the transmission path selection circuit in the interface device is configured to be activated by a signal from another station device, the connection form of the loop can be automatically changed by remote control.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a conventional loop transmission system. FIG. 2 is a configuration diagram of an interface device according to an embodiment of the present invention. FIG. 3 is a configuration diagram of a loop transmission method according to an embodiment of the present invention. FIG. 4, FIG. 5, and FIG. 6 are explanatory diagrams showing the procedure for adding an interface device and a station device. FIG. 7, FIG. 8, and FIG. 9 are explanatory diagrams showing the mounting procedure of the ink face device and the station device. FIG. 10 is an explanatory diagram showing disconnection of the station device when a station device failure occurs. FIG. 11 is an internal configuration diagram of the interface device. FIG. 12 is a diagram showing channel allocation of transmission frames on a transmission path. Patent Applicant Nippon Telegraph and Telephone Public Corporation Agent Patent Attorney Nao Takashi Ide

Claims (1)

[Claims] (l) Three or more interface devices are inserted into a transmission line connected in a loop, a station device is connected to each interface device, and an interface device is installed in each station device. In a loop transmission method configured such that the transmission path connected in a loop is passed through the interface device, each of the above interface devices is configured such that both the outward and return paths of the transmission path between the interface device connected next to the interface device and the interface device connected next to each other are The first selection circuit is configured to pass through the interface device, and each of the above interface devices has a first selection circuit inserted in the outgoing path to select the station device and the downstream ink face device by switching at high speed, A second selection circuit is inserted into the return path, which switches at high speed to select between the outgoing signal going to the interface device downstream of the first selection circuit and the return path from the downstream interface device. Features a loop transmission method. (2) The loop transmission system according to claim 1, wherein the first selection circuit and the second selection circuit are switched and controlled by a remote control signal.