JP2000295236A - Atm transmitter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To recover communication by restoring a fault on the occurrence of the fault in an ATM channel interface connected to an ATM channel. SOLUTION: The ATM transmitter 10 that connects a terminal 30 to an ATM channel 50 is provided with a 0 system ATM channel interface and a 1 system ATM channel interface, one of which is used for an active system and the other of which is used for a standby system as an ATM channel interface circuit 13, that interface the ATM channel with the ATM transmitter 10, an ATM channel interface fault detection means 16 that detects occurrence of a fault by monitoring the ATM channel interface, and a channel selection circuit 14 that connects either of the ATM channel interface to the ATM channel selectively. On the occurrence of a fault in the ATM channel interface of an active system, the ATM channel interface for the standby system is selected to recover communication.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ATM line interface for connecting an ATM transmission device and an ATM line, and more particularly to a printed circuit board (Prin) mounted on an ATM transmission device.
When a failure occurs in the active ATM line interface mounted on the ted Circuit Board (hereinafter referred to as PCB), the ATM line interface is switched to the standby ATM line interface, and the connection between the ATM transmission device and the ATM line is restored.
The present invention relates to an ATM transmission device for restoring communication.

[0002]

2. Description of the Related Art ATM for connecting a terminal device to an ATM line
In the transmission device, a PCB having an ATM line interface circuit is mounted in order to interface the ATM transmission device with the ATM line. Such an A
In the TM transmission device, when a failure occurs in the ATM line interface circuit, communication via the ATM line is interrupted, and a serious problem occurs that subsequent communication cannot be continued. Generally, in a switchboard or the like, by providing an important circuit configuration in duplicate, when a communication failure occurs in the device, the circuit is switched to a PCB equipped with a circuit of the same type as the failed circuit in the device. There is a technology that recovers a failure and recovers communication. However, in ATM transmission equipment, ATM
If the line interface fails, another AT
Switching to the M line interface to restore communication is not performed.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide an ATM transmission apparatus that, when a failure occurs in an ATM interface connected to an ATM line, recovers the failure and recovers the communication without interrupting the communication. Make it an issue.

[0004]

In order to solve the above problems, the present invention provides an ATM for connecting a terminal device to an ATM line.
In the transmission device, an ATM line interface circuit for interfacing the ATM transmission device and the ATM line, wherein the ATM line interface circuit having the ATM line interface and the standby ATM line interface, and the occurrence of a failure by monitoring the ATM line interface Line interface failure detecting means for detecting a failure, and line selecting means for selectively connecting one of the ATM line interfaces to the ATM line.
When a failure occurs in the active ATM line interface, communication is restored by switching to the standby ATM line interface.

Further, according to the present invention, in the above-described ATM transmission apparatus, the working ATM line interface and the standby ATM line interface are mounted on the same printed circuit board (PCB), and the PCB is mounted on the ATM transmission apparatus.

[0006]

When a failure is detected in the working ATM line interface connected to the ATM line, the failure is recovered by switching from the failed working ATM line interface to the standby ATM line interface by setting the line selection circuit. System switching of the line section that restores communication is realized.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of an ATM transmission apparatus according to the present invention will be described below with reference to FIG. ATM transmission equipment 1
0 is a digital service unit (DSU) that works with a plurality of terminal devices 30-1 and 30-2 as network terminating devices.
This is means for connecting 50 to the ATM line via 40.

An ATM transmission apparatus 10 according to the present invention includes a plurality of interface circuits 1 to which a terminal device 30 is connected.
1-1, 11-2, a cell assembly / disassembly (CLAD) circuit 12-1, 12-2, an ATM line interface circuit 13, a line selection circuit (LINSEL) 14, and a control circuit 15 having control wear. , An ATM line interface fault detecting circuit 16 for detecting the occurrence of a fault in the ATM line interface circuit, and a CLAD circuit 1
2 and a data bus 17 for transmitting data between the ATM line interface circuits 13.

The interface circuit 11 is a terminal device 3
It has a function of taking an interface between the ATM transmission apparatus 10 and the ATM transmission apparatus 10.

The CLAD circuit 12 functions to decompose information input from the terminal device 30 via the interface circuit 11 into cells and assemble them into ATM cells.
It has a function of assembling the ATM cell received from the line 50 and restoring the original information.

The ATM line interface circuit 13 comprises:
ATM line interface (0 system) 13-1 and AT
It is composed of a PCB equipped with an M line interface (system 1) 13-2. The ATM line interface circuit 13 has a function of taking an interface between the CLAD circuit 12 and the ATM line 50.
Either -1 or 1-system 13-2 is used as the active system, and the other is standby as a standby system (standby system).

The line selection circuit 14 comprises ATM line interfaces 13-1 and 13-2 operating as an active system.
Has the function of selecting one of them and connecting to the ATM line 50.

The control circuit 15 has a function of controlling each circuit means in the ATM transmission apparatus 10, and is operated by control wear (C / W).
The control circuit 15 performs control described later.

The ATM line interface fault detecting circuit 16 is provided with the ATM line interfaces 13-1 and 13-.
Monitoring the output of the ATM line interface 13
It detects that a failure has occurred in -1, 13-2, and notifies the control circuit 15.

The data bus 17 transmits data between the connected CLAD circuit 12 and the ATM line interface circuit 13.

The processing when a failure occurs in the active ATM line interface 13-1 of the ATM transmission apparatus having the above configuration will be described below. A of current system (for example, 0 system)
When the ATM line interface fault detecting circuit 16 detects that a fault has occurred in the TM line interface 13-1, the control circuit 15 executes the line selecting circuit 1 by the control processing of the interface manager provided inside.
4 to select the standby ATM line interface 13-2 for the standby system (system 1).
Is transmitted to the ATM line 50 via the DSU 40 to restore communication.

Hereinafter, specifications relating to the failure recovery processing will be described. The switching of the ATM line interface is performed by switching to the standby ATM line interface, triggered by the occurrence of a failure in the (active) ATM line interface connected to the ATM line. This switching process is performed after confirming the state of the standby system.

The switching of the ATM line interface is performed by a method of redistributing the configuration information to a task for controlling each physical interface in the C / W. This method is performed by deleting (unused) the configuration information of the failed ATM line interface of each task and adding the configuration information of the standby ATM line interface.

When the system is started up, it is started up by the ATM line interface set to the system 0 according to the configuration information, and is switched to the system 1 ATM line interface when a failure occurs. After switching to the primary ATM line interface, if a failure occurs in the primary ATM line interface, the system is switched back to the primary ATM line interface and the failure monitoring of the primary ATM line interface is performed again. If there is a failure in both the 0-system / 1-system ATM line interface, system switching is repeated. If system switching occurs a certain number of times within a certain period of time, the system is fixed. This time / number can be set in the configuration information.

When the ATM line interface is switched, the status of the standby ATM line interface is monitored, and when the switching is impossible, the system switching is not performed.

When a line connected by a PVC (Permanet Virtual Channel) connection is switched, a cell at the time of system switching is lost.

When a line connected by SVC (Switched Virtual Channel) is switched, all calls in communication are released.

The method of releasing the fixed connection connected by the above processing is performed by the following method. a. When C / W (Control / Ware) rises due to POWER ON or depression of reset switch, etc. b. When the line recovers for a certain period of time set by the configuration information c. When the configuration information is changed d. When a forced system 0 operation is set by an operation command or a system switching process is set by a forced 1 system operation e. When the "ATM line interface forced changeover switch" in the line selection means is changed

The ATM line interface switching factor is given priority in the following order. The highest priority is forced switching by the operation command, followed by the operation of the line forced switching switch, and then the occurrence of a failure in the ATM line interface unit.

The line selection circuit 14 has one independent PCB
And may be removed (not implemented) during operation. The processing when the line selection circuit 14 is not mounted as described above will be described below. If the non-implementation of the line selection circuit 14 is detected for some reason, the system is forcibly set to the 0-system ATM line interface operation. In this case, even if the first line ATM line interface is operating normally, the line selection circuit 1
4 Because other information becomes unreliable, switch to system 0. The non-implementation of the line selection circuit 14 is a target of logging collection and failure notification. In addition, 1
When a command for fixing to the system ATM line interface is input, even if the PCB with the system ATM line interface circuit is not mounted, the system AT
Operates on the M line interface. That is, the operation is performed with the setting content from the operation command as the highest priority.

The system switching process is performed even when the connection of the ATM line interface is detected based on the connection information of the line cable for physically connecting the line selection circuit and the ATM line interface circuit. If the line cable of the switching destination is not connected at the time of line switching,
Does not execute the switching process. If the ATM line interface is not installed, it is subject to logging and fault reporting.

When the mode of the line forced changeover switch for forcibly switching the system mounted on the line selection circuit is the AUTO mode set at the time of shipment, the ATM line interface is switched due to the occurrence of a failure. Perform switching processing. When the forced ATM system interface operation or the forced ATM system interface operation is set, the system switching process is interrupted and the system is fixedly connected to the designated system. Note that this line compulsory switching switch information is set lower in priority than compulsory system switching by an operation command.

Referring to FIG. 2, the contents of the system switching process at the time of switching the configuration information will be described. FIG. 2 shows the contents of the system switching process when there is a change to the line selection circuit and the ATM line interface in the configuration information. Operating (active) ATM line interface is 0
In the system, when the change to the line selection circuit is changed to the 0 or 1 system, when the change to the ATM line interface is the 0 or 1 system change (FIG. 2, state 1), only the 0 system is changed. In the case of (2 in FIG. 2, state 2), when only the 1 system is changed (FIG. 2, state 3), and when there is no change (FIG. 2, state 4), the configuration information is obtained when the line is disconnected The operation system after the switching is the 0 system.

When the operating system (active system) ATM line interface is system 0 and the change to the line selection circuit is changed to system 0, the change to the ATM line interface is changed to system 0 or 1. (State 5, FIG. 2, state 5), when only system 0 is changed (state 2, state 6), when only system 1 is changed (state 7, state 2), and when there is no change (state 8, state 2) In any case, when the line disconnection occurs, the operation system after switching the configuration information is set to 0 system.

When the active system (working system) ATM line interface is system 0 and the contents of the change to the line selection circuit are changed to system 1, the contents of the change to the ATM line interface are changed to systems 0 and 1. (State 9 in FIG. 2) and when only system 0 is changed (state 10 in FIG. 2)
In any case, when the line disconnection occurs, the operation system after switching the configuration information is set to 0 system. When only one system is changed (FIG. 2, state 11) and when there is no change (FIG. 2, state 12), the system is not switched while communication is being performed and the operation system is set to the zero system.

When the operating system (working system) ATM line interface is system 0 and there is no change in the change to the line selection circuit, and the change to the ATM line interface is change 0 or 1 (Figure 2, State 1
3) and when only system 0 is changed (Fig. 2, state 14)
In any case, when the line disconnection occurs, the operation system after switching the configuration information is set to 0 system. When only one system is changed (FIG. 2, state 15) and when there is no change (FIG. 2, state 16), the system is not switched while communication is being performed and the operation system is set to the zero system.

When the operating system (working system) ATM line interface is system 1 and the change to the line selection circuit is changed to system 0 or 1, the change to the ATM line interface is 0 or 1. When the system is changed (FIG. 2, state 17), when only the 0 system is changed (FIG. 2, state 18), 1
When only the system is changed (FIG. 2, state 19) and when there is no change (FIG. 2, state 20), the operation system after switching the configuration information is set to 0 when a line disconnection occurs. .

When the active (active) ATM line interface is system 1 and the change to the line selection circuit is changed to system 0, the change to the ATM line interface is changed to system 0 or 1. (Figure 2, State 2
1) and when only 1 system is changed (Fig. 2, state 22)
In any case, when the line disconnection occurs, the operation system after switching the configuration information is set to 0 system. When only the 0 system is changed (FIG. 2, state 23) and when there is no change (FIG. 2, state 24), the system is not switched while communication is being performed and the operation system is set to the 1 system.

When the active system (working system) ATM line interface is system 1 and the change to the line selection circuit is changed to system 1, the change to the ATM line interface is changed to system 0 or 1. (Figure 2, State 2
5) When only the 0 system is changed (FIG. 2, state 26), when only the 1 system is changed (FIG. 2, state 27), and when there is no change (FIG. 2, state 28), the line is disconnected. When the error occurs, the operation system after the switching of the configuration information is set to the 0 system.

When the operating system (working system) ATM line interface is system 1 and there is no change in the change to the line selection circuit, and the change to the ATM line interface is change 0 or 1 (Figure 2, State 2
9) and when only system 1 is changed (Fig. 2, state 30)
In any case, when the line disconnection occurs, the operation system after switching the configuration information is set to 0 system. When only the 0 system is changed (FIG. 2, state 31) and when there is no change (FIG. 2, state 32), the system is not switched while communication is being performed and the operation system is set to 1 system.

The line switching processing will be described with reference to the PAD flow chart of FIG. When the following factors occur, the training switching process is performed according to the flow of FIG. When a swap command for exchanging the operation system is issued and the line operation system is specified, the operation system is switched to the specified line regardless of the current operation system. When the status change occurs and the 0 system is the active system,
The implementation information of the line selection circuit is periodically monitored. When the switch of the line selection circuit is mounted, the switch of the line selection circuit is changed to the specified system. When there is a change in the state of the active PRI such as ATM line interface mounted / not mounted, ATM line interface failure line failure, etc., when the system is fixed or the operating system is operating normally, system switching is not performed. When the ATM line interface is mounted or not mounted, when the state of the standby PRI changes, when the standby system is normal, switching of the system for switching the standby system to the active system is performed. If there is an abnormality in the standby system, the system is not switched.

As described above, according to the present invention, by providing the above-described configuration, the ATM
When a failure occurs in the ATM line interface connected to the line, it is possible to switch to the standby ATM line interface, recover the failure, and recover the communication.

[0038]

As described above, according to the present invention, when a failure occurs in the ATM line interface connected to the ATM line in the ATM transmission device, communication is restored by switching to the standby ATM line interface and restoring the failure. This makes it possible to recover the data, thereby achieving the duplexing of the ATM line interface.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the concept of the configuration of an ATM transmission device according to the present invention.

FIG. 2 is a view for explaining a line duplication process at the time of switching configuration information of the ATM transmission apparatus according to the present invention.

FIG. 3 is a flowchart showing a line system switching process in the ATM transmission device according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 ATM transmission device 11 interface 12 CLAD circuit 13 ATM line interface circuit 14 line selection circuit 15 control circuit 16 ATM line interface failure detection circuit 17 data bus 30 terminal device 40 DSU 50 ATM line

Claims (2)

[Claims] 1. An ATM for connecting a terminal device to an ATM line.
In a transmission apparatus, an ATM line interface circuit for interfacing an ATM transmission apparatus with an ATM line, comprising an active ATM line interface and a standby A
ATM line interface circuit having a TM line interface, ATM line interface fault detecting means for monitoring the ATM line interface and detecting occurrence of a fault, and a line for selectively connecting one of the ATM line interfaces to the ATM line An ATM transmission device comprising a selection unit, and when a failure occurs in an active ATM line interface, switching to a standby ATM line interface to recover communication. 2. The ATM according to claim 1, wherein the active ATM interface circuit and the standby ATM line interface are mounted on the same printed circuit board (PCB), and the PCB is mounted on the ATM transmission device.
Transmission equipment.