JPS59247A - Terminal circuit connection controlling system of looped communication network - Google Patents

Abstract

PURPOSE:To execute immediately communication without requiring a security time, by constituting so that a communication available display to each terminal circuit connected opposingly is executed synchronously. CONSTITUTION:When completion of connection is informed to a terminal station 3A from the center station, each terminal station 3A sets a data signal switch part 353 of a line unit circuit 35a to an on-state, respectively. Thereafter, each terminal station turns on a control signal switch 352 of the circuit 35a, respectively, but for instance, even in case when the switch part 352 of the circuit 35a side is turned on earilier, a terminal equipment 4A is not connected yet with a terminal equipment of the other side since the switch part of the other side unit circuit is not turned on. In this state, when the switch part of the other side unit circuit is turned on, a control signal line C and I between the equipment 4A and the other side terminal equipment are connected mutually, an on- signal to the line C from the terminal equipment is sent out to each of the line I of the other side terminal equipment of communication, and it is known that the equipment 4A and the other side terminal equipment are in a mutual communication available state.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a terminal line connection control system for a ring communication network in which a central station having a centrally located processing unit and a plurality of terminal stations having distributed terminal equipment are connected by a loop-shaped transmission path. Regarding.

Conventionally, in a data highway system with a line switching function, the line control function is distributed to display the communicable status of each connected terminal line, resulting in time lag. After receiving the communication, communication had to be started after a predetermined guaranteed time period during which communication enabled status was displayed on the opposite side.

An object of the present invention is to make it possible to perform instant communication without requiring the above-mentioned guaranteed time by making it possible to display the communication availability status for each terminal line that is connected to each other in synchronization. The purpose is to provide a control method for connecting the end of a ring communication network to a non-circuit connection.

The terminal line connection control method according to the present invention consists of a central station that monitors and controls the entire communication network, a plurality of terminal stations that are subordinate to the central station and that monitor and control the terminal lines that it accommodates, and 'f: a circular transmission path. In the ring communication network, each of the terminal stations accommodates at least one transmitting and receiving terminal line each interconnected with the communication end station via the transmission path, and the transmitting and receiving terminal A switching means is provided for connecting/disconnecting a connection path between a line and the transmission line, and the terminal circuit is connected between the terminal circuits by a connection status display signal that passes when the switching means of each of the mutual communication tip stations performs a connection operation. The connection is completed.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a terminal line connection control method for a ring communication network according to the present invention. In the figure, a central station CC3) 2 and a plurality of terminal stations (TDS) 3A to 3N are connected by a loop-shaped transmission line 1 to form a ring communication network. In this data highway system, a central station 2 controls the supervisory control and circuit switching processing of the entire system, and terminal stations 3A to 3N each have a terminal equipment (DTE) 4.
The terminal lines 58 to 5N that accommodate 8 to 4N are allocated to the monitoring side. Further, the loop-shaped transmission line 1 is a transmission line having a time division multiplex channel configuration that mainly transmits line data. Transmission circuit (HWTR) 21 for central station 2 and terminal stations 3A to 3N
31a to 31n are connected by a transmission line 1 and control data transmission by time division multiplexing. Control channel circuits (CTLCH) 22.32a to 32n are connected to the transmission circuits 21, 31a to 31n, respectively, and transfer exchange control information between the central station 2 and each terminal station 3A to 3N using a specific channel (control channel) of the transmission line 1. ). Central station 2
The processor circuit (PC) 23 of the control channel circuit 22
The processor circuits (PC) 333 to 33n of each terminal station 3A to 3N are connected to the control channel circuits 32a to 32n of the own station and the line unit circuit (
LUT) 358 to 35n and performs line control. Time division switch f circuit (TDSW) 34 a ~ 34
n are connected to the control channel circuits 328 to 32n, respectively, and controlled by the processor circuit 23 of the central office 2 via the control channel of the transmission line l, and are connected to the terminal lines 5A to 5N.
are respectively switched and connected to designated channels of transmission path l. In addition, line unit circuits 358-35n are connected to terminal lines 58-5N, respectively, and are monitored and controlled by processor circuits 33a-33n of the own station.

Next, referring to FIG. 2, which shows the configuration of the terminal station 3A, which is representative of the details of the terminal line connection of each terminal station 38 to 3N in FIG. 52, 53, 54t- to the terminal device 4A to the level converter (LVCV) of the line unit circuit 35a.
354 is connected and accommodated. Here, the line (T) 51 carries the data signal from the terminal device 4A, the line (C) 52 carries the same control signal, the line (J53 carries the data signal to the four terminal devices, and the line (I) 54 carries the same control signal. The data signal switch section (DLSW) 353 of the line/unit circuit 35a is a signal changeover switch for the line 53, and when turned on, forms a connection path to the time division switch circuit 34a, and turned off. Time is line control character signal 8Y
It has a function to send out N.

In addition, the control signal switch section (8LSW) 352 is
This is a signal changeover switch for J52 and J54, and when it is on, it transmits a control signal to the line 52 and 54, and when it is off, it is disconnected from the line 52 and sends the off signal OFF via the in-channel control unit (INCH) 351. It has a function of sending an OFF signal OFF to the time division switch circuit 34H and also sending an OFF signal OFF to the port 54. The in-channel control section 351 has a function of multiplexing and demultiplexing control signals and data signals for the in-channels of the time division switch circuit 34M. In addition, the time division switch circuit 34a connects the line unit circuit 35a to the designated channel of the transmission path l when connected.
It has a function of transmitting a mark signal MRK as a data signal and an off signal OFF as a control signal to the line unit circuit 358 when the line unit circuit 358 is connected and disconnected.

Next, the line connection operation will be explained. First, referring to FIG. 3 which shows the concept of line signal flow, there are the following states as interface states with each terminal device.

Connection preparation letter m* Connection completed state Communication ready state T@
MARK MARK MARKC,W
ON ON ON
R line SYN −+ MARK MA
R.K.

T line OFF OFF →
As you can understand, the signal sent from the terminal is the ON signal to the M line to Ti@l and the ON signal to the C line, while the signal from the terminal to the terminal is not in the connection preparation state. The SYN signal of the R line person and the OFF signal to the T line are applied, and when the state changes to the connection completion state, the R line becomes the MRK signal, and when the state changes to the communicable state, I11! When the ON signal is turned on, each terminal becomes ready for communication. Next, the line connection operation will be described in detail with reference to FIGS. 1, 2, and 3 to 4. Before connecting the line, each terminal station is 38 to 3N
The data signal switch section 353 and control signal switch section 352 of the line unit circuits 35a to 35n are in the off state, and the R line is 8Y for the terminal devices 48 to 4N.
The N@ and T lines are sending OFF signals. Also, from terminal devices 48 to 4N, T line MA R, K signal, C line ON
A signal is being sent. In this state, the processor circuit 23 of the central station 2 controls the time division switch circuits 34a, 34n via the control channel circuits 32a, 32n of the terminal station 3A and terminal station 3N, and the line unit circuit 3
5a and 351 are connected via a predetermined channel of transmission line 1. Accordingly, as shown in the third position, terminal station 3A
Preparations for connection between and 3N are completed.

Thereafter, when the processor circuit 23 of the central station 2 notifies the processor circuits 33a and 3an of the terminal stations 3A and 3N of the completion of connection via the control channel circuits 32B and 32n, the processor circuits 33a and 33n are connected to the line units. Data signal switch section 3 of circuit 358°35n
53 are respectively turned on. For this, terminal station 3
The T line and R line between A and the terminal station 3N are connected to each other, and the MRK signal of the T line from the opposite terminal device is sent to each of the nine lines, so that both terminal devices 3A and 3N know the connection completion state. After that, the processor circuit 33a of each terminal station.

33n turns on the control signal switch section 352t of the line unit circuits 35a and 35n, for example, the control signal switch section 352 of the line unit circuit 35a side
Even if the terminal device 4A and terminal device 4N are turned on earlier in time, the control signal switch section 352 of the communication partner line unit circuit 35n is not turned on, so that the terminal device 4A and the terminal device 4N are not yet connected as shown in FIG. In this state, when the control signal switch section 352 of the line unit circuit 35n is turned on, the control signal lines C and T between the terminal device 4A and the terminal device 4N are turned on.
The lines are connected to each other, an on signal from the terminal device to line C is sent to each of the communication partner terminal devices Ii, and the terminal devices 4A and 4N know that mutual communication is possible (the third
Figure (to)).

As you can understand from the above operation explanation, terminal stations 3A and 3N
Even if the control timing from the central station 2 differs, each terminal station can display the communicable state to the terminal devices 4A and 4N in synchronization.

As described above, according to the present invention, it is possible to synchronously display the communicable state of the terminal line of the communication partner accommodated in each terminal station, thereby making it possible to perform instant communication.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the overall configuration of an embodiment of the present invention, and FIG.
This figure is a detailed configuration diagram of the part related to line signals in FIG. 1, and FIG. 3 is a diagram showing the flow of line signals. l...Loop-shaped transmission line, 2...Central station, 3A. 3N...Terminal station, 4A, 4N...Terminal device, 5A. 5N...Terminal line, 21,318,31rl・
...Transmission circuit, 22, 32a, 32n...
・Control channel circuit, 23, 33a, 33n...
- Processor circuit, 34a, 340... Time division switch circuit, 35a. 35n...Line unit circuit, 351...
... In-channel control section, 352 ... Control signal switch section, 353 ... Data signal switch section, 354 ... Level conversion section. Figure 3 (, 4) Figure 173<c) Third close (B) Figure 3 CD)

Claims (1)

[Claims] In a ring communication network consisting of a central station that monitors and controls the entire communication network, a plurality of terminal stations that are distributed subordinate to the central station and monitors and controls the terminal lines that it accommodates, and are connected by a 'tl-ring transmission path, Each of the four stations is a transmitting and receiving terminal 1g that is interconnected with the communication tip station via the l thick transmission path.
and a switching means for connecting/disconnecting the connection path between the transmitting and receiving terminal line and the transmission path, and each of the switching means of the mutual communication tip station performs a connecting operation. 1. A terminal line connection control system for a ring communication network, characterized in that connection between the terminal lines is completed by a connection status display signal that is Aa.