JP3171781B2 - Line compatible switching system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a rotating line corresponding switching system, for example, the new synchronous digital high Araki (SD
H: Synchronous Digital Hie
A line corresponding unit for accommodating a (rarchy) line or the like is duplexed into an active system and a standby system, and can be applied to a case where system switching is performed.

[0002]

2. Description of the Related Art In recent years, ATMs (As
ynchronous Transfer Mode:
(Asynchronous transfer mode) In order to guarantee high reliability, it is generally required that the line corresponding portion of the exchange be duplexed into an active system and a standby system. Such a technique is proposed in, for example, the following document 1.

Reference 1: IEICE, May 1993
Tsuki, Technical Research Report SSE93-18, Masaru Murakami, "ATM
Switching of line-corresponding sections in exchanges ”.

This document 1 describes a control method for switching the duplexing of a line corresponding section in an ATM exchange. The operation of the switching system in the SDH multiplex converter is defined in the following document 2.

Reference 2: Telegraph and Telephone Technical Committee, 1
994, "Inter-network interface-inter-network transmission method", Vol. 3, 1st volume, Eighth Edition, JT-G783, "Operation of alarm system and switching system of SDH multiplex converter".

Here, two SDH lines are taken in and used as an active system and a standby system, and switching between duplication of the active system and the standby system will be described. That is, 1 + 1 bidirectional switching (automatic switching: APS: Automat) in a switching device having a dual SDH line interface
An ic Protection Switching) control system will be described below.

FIG. 2 is a block diagram of an ATM switch in which a line corresponding section is duplicated. In FIG. 2, AT
The M exchange comprises a 0-system (working system) line corresponding unit 4a, a 1-system (standby system) line corresponding unit 4b, a 0-system ATM switch circuit SW0, and a 1-system ATM switch circuit SW1.

The 0-system (working system) line corresponding unit 4a is an SDH
An SDH interface circuit 2a for accommodating a line;
An ATM cell processing circuit 3a for processing (for example, performing header conversion, etc.) the ATM cells taken into the H interface circuit 2a, and an SDH interface circuit 2a and A
It comprises a switching control firmware circuit (APS) for controlling the TM cell processing circuit 3a and a microprocessor circuit (μp) 1a having a line termination firmware circuit.

This microprocessor circuit (μp) 1a
Is to operate a switching control firmware circuit (APS) and a line termination firmware circuit under the control of a host device to execute switching control and line termination.

The 1-system (standby) line corresponding unit 4b has the same configuration as the 0-system (working system) line corresponding unit 4a, and executes switching control and line termination under the control of a higher-level device. It is.

An ATM cell line-terminated by the 0-system (working system) line-corresponding unit 4a is transmitted to the 0-system AT through the confounding point 1.
M switch circuit SW0 and 1-system ATM switch circuit SW
1 is supplied. In addition, a 1-system (standby system) line corresponding unit 4
The ATM cell line-terminated at b is also supplied to the 0-system ATM switch circuit SW0 and the 1-system ATM switch circuit SW1 through the confounding point 1.

In FIG. 2, the 0-system (working-system) line corresponding units 4a and 1 excluding the switching control firmware circuit (APS)
The system (standby) line corresponding unit 4b is configured such that the switching control firmware circuit (APS) is linked with the system whose transmission path is selected to act (operation state) / standby (non-operation state).
To determine. Also, a switching control firmware circuit (AP
Since the act / standby of S) is also linked with the protection channel / working channel of the transmission line, the switching control firmware circuit (APS) itself determines the act / standby.

Therefore, the switching control firmware circuit (A
PS), both the 0-system (working system) line corresponding unit 4a and the 1-system (standby system) line corresponding unit 4b including the other transmission lines act in conjunction with the switching control firmware circuit (APS) of the opposite device. / Standby.

Here, the transmission line switching system is internationally standardized, and is a system in which switching is performed in conjunction with a line terminating unit in another facing system.

FIG. 3 is a diagram illustrating an example of transmission line switching. In FIG. 3, transmission line switching will be described with a connection configuration in which the A-station ATM exchange and the B-station exchange face each other. First, if there are no faults in the transmission lines and line terminating units of both stations A and B, and the 0-system (working system) transmission line is used as the working channel and the 1-system (protection system) transmission line is used as the protection channel, the A and B stations Both stations are 0
Data extracted from the transmission path of the system is selected. That is, in the line termination unit excluding the switching control firmware circuit (APS), the 0 system (working system) 4a is active, and in the switching control firmware circuit (APS), the 1 system (standby system) 4b is active (FIG. 3 (a)).

Here, when switching to the 1-system (standby system) transmission line is attempted due to the detection of a signal failure at the A station, a switching request signal is transmitted from the A station to the B station.
That is, a switching request for SF switching is notified. When receiving the switching request signal from the A station, the B station determines whether or not the switching is possible. If the switching is possible, the B station switches to the data extracted from the 1st (standby) transmission line. That is, the line termination unit excluding the switching control firmware circuit (APS) is changed to the 1-system (standby system) act (FIG. 3B). Then, a switching response is returned to the station A. That is, the switching response of the SF switching is notified. At this time, the operation / standby of the switching control firmware circuit (APS) is not changed in the station B (FIG. 3B).

Next, upon receiving this switching response, the A station switches to data extracted from the primary (standby) transmission line. That is, the line terminating unit excluding the switching control firmware circuit (APS) is changed to the 1-system (standby system) act (FIG. 3C).

Thereafter, when the signal failure is cleared at the station A, a recovery wait signal is transmitted to the station B, and a recovery wait release signal is transmitted to the station B after a specified time has elapsed. That is, the switching release request is notified. When receiving the switch release request, the station B changes the name of the system 0 transmission line to the spare channel, changes the name of the system 1 transmission line to the working channel, returns a response of the switch release to the station A, and switches the switching control firmware circuit (APS). ) Is changed to the 0 system (FIG. 4A).

At the station A, upon receiving the switching release response, the station B
Similarly to the station, the system 0 transmission line is changed to the spare channel, the system 1 transmission line is renamed to the working channel, and the act system of the switching control firmware circuit (APS) is changed to the system 0 (FIG. 4 (b)). )).

Here, the host device periodically reads the act / standby state of the line termination firmware circuit other than the switching control firmware circuit (APS),
Alternatively, it is recognized by an interrupt notification from the line termination firmware circuit and the switching control firmware circuit (APS) after the state change.

[0021]

However, in the transmission line switching method described above, the switching control firmware circuit (A
PS) independently performs the switching control with the opposite station, so that it takes time for the higher-level device to recognize which system is the act system, and the act /
There is a problem that a discrepancy occurs between the standby state and the act / standby recognition of the higher-level device, and an instruction to the act system is erroneously given to the standby system.

For this reason, system 0, which is recognized by the higher-level device,
Act / standby state of the 1-system line corresponding unit and actual 0
It is possible to minimize the discrepancy between the act (active) / standby (non-operating) state of the system and system 1 line corresponding parts, and efficiently perform transmission line system switching and device (line corresponding part) switching with a simple configuration. the provision of that times line corresponding switching system has been demanded.

[0023]

According to a first aspect of the present invention, there is provided a line corresponding switching system according to any one of the following (A) to (C): A line-compatible switching system including a device, wherein a first transmission line and a first line-corresponding means of a first station and a second station are set in an operation (act) state as an active system in advance, and a second transmission is performed. When the line and the second line corresponding unit are in the non-operating (standby) state as the standby system and the “switching of the transmission line system” of the working system and the standby system is performed from these states, the first The first switching control unit of the first line corresponding unit of the station operates the second interface unit by supplying a switching request signal to the second interface unit of the second line corresponding unit of the second station. (Act) state,
The first interface unit of the first line-corresponding means of the second station is brought into a non-operating (standby) state, and when these state switches are completed, the first interface of the first line-corresponding means of the first station is completed. Unit to an asynchronous (standby) state and the second interface unit of the second line handling unit to an operation (act) state, and the second transmission line of the first station and the second station and the second transmission line of the second station. The switching of the transmission line system is performed so that the interface unit and the working transmission line system are used.

(A) First time for accommodating first transmission line
Line correspondence means and a second line pair accommodating the second transmission line
And one of the transmission lines and lines
The means operates as the active system and the other operates as the standby system
Control by an external device or the judgment of the line corresponding means.
Active transmission line and line handling means, and standby transmission
Time when the correspondence between the line and the line corresponding means is switched
A line corresponding switching device, wherein the first line corresponding means includes:
A first interface unit that accommodates a first transmission line;
A first transmission line accommodated in the first interface unit
A first processing unit for processing and outputting the main signal of
The first interface is operated by a command from the device or by a situation judgment.
Controlling the face unit and the first processing unit;
A first switching control unit for switching and controlling the second line corresponding means.
Wherein the second line-corresponding means comprises the second transmission line.
And a second interface unit for accommodating the
Process the main signal of the second transmission line accommodated in the interface unit
And a second processing unit for outputting the command from the external device
Or, depending on the situation judgment, the second interface unit and
In addition to controlling the second processing unit, the first line handling unit
Line compatible with a second switching control unit for switching control of the stage
A switching device, wherein the line-compatible switching device is
First processing from the first interface unit of the line handling unit
And the second input of the second line corresponding means.
Between the interface and the second processing unit.
Main signal cross connection for connecting between both line compatible means
Connection means or main signal confounding connection means.
The first transmission line and the first line-corresponding means are set to the active system.
The second transmission line and the second line pair.
When the response is inactive as a standby system,
From these states, disconnect the active and standby transmission line systems.
When performing the change, the first line corresponding means
The switching control unit includes a second interface of the second line corresponding unit.
And a first line corresponding means.
Switch the first interface unit to the inactive state
It is. (B) First line corresponding means for accommodating a first transmission line
And second line corresponding means for accommodating the second transmission line.
Provided, either one of the transmission lines and line corresponding means is in use
System, the other operates as a standby system, and external devices
Transmission of the active system based on control from
Transmission line and line correspondence means, and backup transmission line and line
Line-compatible switching equipment that can switch the correspondence with the corresponding means
Wherein the first line-corresponding means comprises a first transmission circuit.
A first interface unit for accommodating the line, and the first interface unit;
The main signal of the first transmission line accommodated in the interface unit is processed.
A first processing unit for processing and outputting, and a command from the external device.
The first interface unit and the
And controls the first processing unit and supports the second line.
A first switching control unit for switching control of the means.
The second line corresponding means is a second line accommodating the second transmission line.
2 interface section and the second interface section
Processes and outputs the main signal of the second transmission line accommodated in
A second processing unit, and a command or status determination from the external device.
The second interface unit and the second processing unit
And switching control of the first line corresponding means.
And a second switching control unit that performs switching.
The line-compatible switching device is provided with the first line-compatible means.
From the first interface unit to the first processing unit
And a second interface unit of the second line corresponding means.
Both of the above circuits between the path from
Main signal cross connection means for connecting between corresponding means
Means that the main signal confounding connection means is interposed, and the first transmission line
And operating the first line corresponding means as an active system,
Using the second transmission line and the second line corresponding means as a standby system
While in the non-operation state, the active system
And when switching the above line handling means of the standby system
Is the first line-handling method according to an instruction from an external device.
The first interface section of the stage remains active
Then, the first switching control unit and the first processing unit are brought into a non-operation state.
And the second interface unit of the second line corresponding means
The second processing unit and the second
The switching control unit is switched to an operation state. (C) In addition to the configuration of the above (B) line-compatible switching device, the first
The first line terminating unit to the second line means.
Also has a second line terminating unit, which is used for the working system and the protection system.
When switching the line handling means, use an external device.
The second processing unit and the second switching control unit
A line pair that also activates the second line termination section in conjunction with
Switching device. In the structure of the invention according to claim 1, operation of the first line interface means and the second line interface means external device is recognized (act) / and non-operation (standby) mode, the actual Operation (act) / non-operation (standby) of first line corresponding means and second line corresponding means
A discrepancy with the state is less likely to occur, and transmission line system switching and device (line corresponding means) switching can be efficiently performed with a simple configuration.

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a preferred embodiment of the present invention will be described with reference to the drawings. Therefore, in the present embodiment, a new synchronous digital hierarchy (SDH)
In a switching device having an interface, a transmission line switching function is provided in a processor of a line termination unit, and a main signal confound is provided in a line termination unit after a section termination unit of the SDH interface function or with a subsequent device. The hardware of the interface unit on the transmission line side is switched from the transmission line and the main signal confounding point by the switching control function, the switching of the processor unit including the transmission line switching function is instructed by the host device, and the transmission is performed by the firmware of the line termination unit. In conjunction with the line switching control, the hardware of the interface unit on the transmission line side is simultaneously switched from the transmission line and the main signal confounding point, so that the hardware switching unit between the transmission line switching control unit and the line termination unit and the processing of the higher-level device SDH deployed at the line termination unit where
Configure automatic switching mode.

FIG. 1 is a functional block diagram of an ATM exchange according to an embodiment of the present invention, mainly focusing on a line corresponding unit of system 0 and system 1. In FIG. 1, the ATM exchange comprises a system 0 line corresponding unit 4a ', a system 1 line corresponding unit 4b', a system 0 AT
It comprises an M switch SW0 and a 1-system ATM switch SW1. The 0-system line corresponding unit 4a 'and the 1-system line corresponding unit 4b' each accommodate an SDH line. 0
SD between the system line corresponding unit 4a 'and the system line corresponding unit 4b'
An ATM cell accommodating the H line and terminating the line is connected to the 0-system ATM switch SW0 and the 1-system AT via the confounding point 1.
It is configured to be provided to the M switch SW1.

One of the characteristic features of the present embodiment is that a confounding point 2 is formed between the 0-system line corresponding unit 4a 'and the 1-system line corresponding unit 4b'. It is. The confounding point 2 enables a confounding connection to the main signal (ATM cell).

By this confounding point 2, for example, 0
ATM cells from the SDH interface circuit 2a of the system are supplied to the cell processing circuit 3a of the system 0, and ATM cells from the SDH interface circuit 2a of the system are switched to the cell processing circuit 3b of the system 1 by switching control. Given. The ATM cells from the SDH interface circuit 2b of the first system are supplied to the cell processing circuit 3b of the first system, and the ATM cells from the SDH interface circuit 2b of the first system are changed by the switching control. It is provided to the circuit 3a.

Further, the SDH interface circuits 2a, 2a
Since not only the flow of ATM cells from b to the cell processing circuits 3a and 3b but also the flow of reverse ATM cells from the cell processing circuits 3a and 3b to the SDH interface circuits 2a and 2b are controlled by the confounding point 2, is there.

The 0-system line corresponding section 4a 'includes an SDH interface circuit 2a, a cell processing circuit 3a, and a microprocessor circuit 1a. Further, the microprocessor circuit (μp) 1a is composed of a microprocessor, a program ROM, a working RAM, and an interface unit, and a switching control firmware circuit (AP).
S) and a line termination firmware circuit are realized. The control operation of the microprocessor circuit (μp) 1a is controlled by a higher-level device and monitored.

The 1-system line corresponding section 4b 'also includes an SDH interface circuit 2b, a cell processing circuit 3b, and a microprocessor circuit 1b. Further, the microprocessor circuit (μp) 1b is composed of a microprocessor, a program ROM, a working RAM, and an interface unit, and a switching control firmware circuit (AP).
S) 1b1 and a line termination firmware circuit 1b2 are realized. This microprocessor circuit (μp) 1
The control operation b is also controlled by the host device and monitored.

The hardware replacement unit of the 0-system line termination unit 4a 'and the 1-system line termination unit 4b' is not separated between the SDH interface circuits 2a and 2b and the cell processing circuits 3a and 3b, and is replaced collectively. And That is, the line termination unit 4a
, 4b 'are managed integrally by the SDH interface circuits 2a, 2b and the cell processing circuits 3a, 3b.

A switching control firmware circuit (AP
S) A confounding connection of control signals between the systems is required for 1a1 and 1b1, and such a confounding connection forms a control signal transfer route between the 0 system and the 1 system. .

The SDH interface circuits 2a and 2b
It accommodates an SDH line and exchanges ATM cells with the cell processing circuits 3a and 3b. The SDH interface circuits 2a and 2b are provided with a switching control firmware circuit (APS)
1a1 and 1b1 determine act / standby in conjunction with the system in which the transmission path is selected. Further, the act / standby of the cell processing circuits 3a, 3b including the switching control firmware circuits (APS) 1a1, 1b1 is determined according to the instruction of the host device.

Therefore, the switching control firmware circuit (A
PS) Cell processing circuits 3a, 3b including 1a1, 1b1
Then, the act / standby is determined independently of the SDH interface circuits 2a and 2b including the 0-system and 1-system transmission lines.

(Transmission path system switching operation): FIGS. 5 to 7
FIG. 3 is a diagram for explaining the operation of switching the transmission line system between the system 0 and the system 1 in a system in which the A-station ATM exchange and the B-station ATM exchange face each other. The transmission line system switching method is
CCITT Recommendation G. It is standardized internationally, such as 783, and it is assumed that transmission line switching is performed in conjunction with a line terminating unit in another system facing the system.

First, both the stations A and B have no fault in the transmission line, the 0-system line termination section 4a 'and the 1-system line termination section 4b'.
When the 0-system transmission line is a working channel and the 1-system transmission line is a protection channel, both stations A and B select data extracted from the 0-system (working) transmission line. That is, in the line termination unit 4a ', the 0 system is acted. (FIG. 5
(A), the hatched part is the act state. Here, at the station A, when switching to the 1-system (standby system) transmission line due to a signal failure, the switching request signal is transmitted from the A station to the B station. That is, a switching request for SF switching is notified.
When receiving the switching request signal from the A station, the B station determines whether or not the switching is possible. If the switching is possible, the B station switches to the data extracted from the 1st (standby) transmission line. That is, only the SDH interface circuit 2b of the station B is changed to the 1-system act (FIG. 5B). Then, a switching response is returned to the station A. That is, SF (signal failure: Signal Fa)
il) Return a switching response for switching.

Upon receiving this switching response, the A station switches to the data extracted from the 1-system transmission line. That is, SDH
Only the interface circuit 2b is changed to the 1-system act. Thereafter, when the signal failure SF is released at the station A, a restoration wait signal is transmitted to the station B, and after a lapse of a predetermined time, a restoration wait release signal is transmitted to the station B (FIG. 6A).
That is, the switching release request is notified.

When the station B receives this switching release request,
The 0-system transmission line is changed to the spare channel, the 1-system transmission line is renamed to the working channel, and a response to the switching release is returned to the A station (FIG. 6B). At this time, the SDH interface circuit 2a
However, the act system of the line terminating unit 4a 'except for the above is not changed, and the act system 0 maintains the act state.

When the station A receives the response of the switching release, the station B
Similarly to the station, the system 0 transmission line is set as a spare channel and the system 1 transmission line is renamed to the working channel (FIG. 7). At this time,
Even in the A station, the act system of the line terminating unit 4a 'excluding the SDH interface circuit 2a is not changed, and the act system 0 maintains the act state.

(Device (line termination unit) switching operation): FIG. 8 shows the line termination units 4a 'and 4a'
FIG. 9 is an operation explanatory diagram for switching line termination units 4a ′ and 4b ′ other than the SDH interface circuits 2a and 2b of b ′.

In FIG. 8, the line terminating units 4a 'and 4b' other than the SDH interface circuits 2a and 2b are controlled independently of the act / standby of the SDH interface circuits 2a and 2b including the transmission line by the host device.
The line terminating units 4a 'and 4b' other than the SDH interface circuits 2a and 2b are switched without interlocking with the opposing device (station B) according to the instruction of the host device (FIG. 8).
(A) → (b)). That is, the switching is performed without taking the switching request / response sequence.

In FIG. 8, the internal confounding point 2 between the line termination units 4a 'and 4b' for the 0 system and 1 system is omitted for simplification of the description of the switching operation. SDH interface circuits 2a and 2b select information from the activated cell processing circuits 3a and 3b, and
The line termination units 4a 'and 4b' of the system and the system 1 select information from the activated SDH interface circuits 2a and 2b.

In this way, the switching control of the SDH interface circuits 2a and 2b including the transmission path and the circuits of the line terminating units 4a 'and 4b' other than the SDH interface circuits 2a and 2b are independently performed.

Note that the SDH interface circuits 2a and 2b are not included due to failure of the line terminators 4a 'and 4b'.
When it is necessary to switch between the system line terminating units 4a 'and 1b, the higher-level equipment sends the line terminating units 4a' and 4b '
The switching command is supplied to 'and the line termination firmware circuits 1a2 and 1b2 execute the switching by combining any one of the operation flows of FIGS. 5 to 8 described above.

Here, the active / standby state of the host device and the SDH interface circuits 2a and 2b is determined by periodically reading the state or changing the state after the line termination firmware circuits 1a2 and 1b2 and the switching control firmware circuit ( Although it can be recognized by the interrupt notification from the APS 1a1 and 1b1, there is basically no need to recognize which of the SDH interface circuits 2a and 2b is activated.

The SDH interface circuits 2a, 2a
Since the act / standby state of the circuit terminating units 4a 'and 4b' other than b changes only with an instruction from the higher-level device, the higher-level device always recognizes the state.

(Effects of Embodiment of the Present Invention) According to the above embodiment of the present invention, the transmission line system switching control function (ie, the switching control firmware circuit (APS) )), The upper device performs the act switching, so even if the transmission line system switching is performed between the transmission line system switching control function and the remote device,
It is possible to prevent a difference between the act / standby state of the line terminating units 4a 'and 4b' and the act / standby of the higher-level device from occurring, and to normally execute an instruction from the higher-level device.

Further, when a line termination unit switching instruction is received from a higher-level device, the transmission line system switching control function performs transmission line system switching control with the opposing device, and simultaneously switches the transmission line / opposed device. , The higher-level device includes the SDH interface circuits 2a and 2b and the other line terminating units 4a ',
4b 'can be integrated and managed without recognizing that the act / standby of the circuit of 4b' does not match.

Furthermore, since the host device can integrate and manage the SDH interface circuits 2a and 2b and the other line termination units 4a 'and 4b' circuits, even if the main signal confounding point 2 exists, the SDH interface circuit 2a , 2b and other hardware circuits can be integrated.

(Other Embodiments) (1) In the above embodiment, the confounding points are arranged between the SDH section and the cell processing section, but the section termination section in the SDH section has been described. A confounding point may be provided between the ATM cell switch and the ATM cell switch. Further, switching between the active system and the standby system can be applied to both the return mode and the non-return mode.

(2) In the above-described embodiment, an example in which the present invention is applied to an ATM exchange has been described. However, the present invention can be applied to any SDH interface device equipped with a microprocessor.

(3) Further, in the above-described embodiment, the description has been made as the confounding point 2 of the main signal. However, the confounding is the same even if it is realized as a cross connection point.

(4) Furthermore, it is preferable that the switching control firmware circuit (APS) and the line termination firmware circuit are realized by logical hardware circuits.

[0055]

According to the present invention, in the first station and the second station, the operation / non-operation state of the first line corresponding means and the second line corresponding means recognized by the external device is determined. The actual operation of the first line corresponding means and the second line corresponding means /
It is possible to realize a line-compatible switching system that makes it difficult to cause discrepancies with the non-operational state and efficiently switches the transmission line system and switches the device (line-compatible means).

[Brief description of the drawings]

FIG. 1 is a functional configuration diagram mainly of a line corresponding portion of an ATM exchange according to an embodiment of the present invention.

FIG. 2 is a functional configuration diagram mainly showing a line corresponding unit of the conventional ATM exchange;

FIG. 3 is an explanatory diagram (part 1) of an operation of a conventional transmission line switching method.

FIG. 4 is a diagram (part 2) illustrating the operation of the conventional transmission line switching method.

FIG. 5 is an explanatory diagram (part 1) of an operation of transmission line switching according to the embodiment;

FIG. 6 is a diagram (part 2) illustrating the operation of switching the transmission line according to the embodiment.

FIG. 7 is an explanatory diagram (part 3) of an operation of switching a transmission line according to the embodiment;

FIG. 8 is an explanatory diagram of an operation of device switching according to the embodiment.

[Explanation of symbols]

1, 2, ... confounding point, 1a, 1b ... microprocessor circuit, 1a1 ... switching control firmware circuit (AP
S), 1a2 ... line termination firmware circuit, 2a, 2
b ... SDH interface circuit, 3a, 3b ... cell processing circuit, 4a '... 0 system line termination unit, 4b' ... 1 system line termination unit.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasushi Takagi 3-19-2 Nishishinjuku, Shinjuku-ku, Tokyo Nippon Telegraph and Telephone Corporation (72) Inventor Masahiko Takaya 3-19, Nishishinjuku, Shinjuku-ku, Tokyo No. 2 Within Nippon Telegraph and Telephone Corporation (56) References JP-A-4-371096 (JP, A) JP-A-8-256159 (JP, A) JP-A-8-335943 (JP, A) (58) Fields surveyed (Int. Cl. ⁷ , DB name) H04L 12/56 H04L 12/28

Claims (2)

(57) [Claims] To claim 1, wherein each of the first station and the second station, the lower
A line-compatible switching system including any one of the line-compatible switching devices according to any one of (A) to (C) , wherein the first transmission line of the first station and the second station and the first transmission line
When the second transmission line and the second line corresponding unit are inactive as the standby system, the active and standby transmission lines are switched from these states. When switching the system, the first switching control unit of the first line corresponding unit of the first station is provided with a second interface unit of the second line corresponding unit of the second station. And a switching request signal is supplied to make the second interface unit operative, and the first interface unit of the first line-corresponding means of the second station is brought into a non-operating state. Then, the first interface unit of the first line-corresponding means of the first station is deactivated, and the second interface unit of the second line-corresponding means is activated. Second transmission of the second station Line interface switching system and carrying out the lines and the second interface unit to switch between the transmission line system to a transmission line system of the working system. (A) First line corresponding means for accommodating a first transmission line
And second line corresponding means for accommodating the second transmission line.
Provided, either one of the transmission lines and line corresponding means is in use
System, the other operates as a standby system, and external devices
Transmission of the active system based on control from
Transmission line and line correspondence means, and backup transmission line and line
Line-compatible switching equipment that can switch the correspondence with the corresponding means
Wherein the first line-corresponding means comprises a first transmission circuit.
A first interface unit for accommodating the line, and the first interface unit;
The main signal of the first transmission line accommodated in the interface unit is processed.
A first processing unit for processing and outputting, and a command from the external device.
The first interface unit and the
And controls the first processing unit and supports the second line.
A first switching control unit for switching control of the means.
The second line corresponding means is a second line accommodating the second transmission line.
2 interface section and the second interface section
Processes and outputs the main signal of the second transmission line accommodated in
A second processing unit, and a command or status determination from the external device.
The second interface unit and the second processing unit
And switching control of the first line corresponding means.
And a second switching control unit that performs switching.
The line-compatible switching device is provided with the first line-compatible means.
From the first interface unit to the first processing unit
And a second interface unit of the second line corresponding means.
Both of the above circuits between the path from
Main signal cross connection means for connecting between corresponding means
Means that the main signal confounding connection means is interposed, and the first transmission
The line and the first line corresponding means are put into operation as the active system.
Then, the second transmission line and the second line corresponding means are reserved.
When the system is inactive,
To switch between the active and standby transmission line systems
In the case, the first switching control unit of the first line corresponding means
Operates the second interface unit of the second line corresponding means.
Operation state, and the first line
The interface is switched to a non-operating state. (B) First line corresponding means for accommodating a first transmission line
And second line corresponding means for accommodating the second transmission line.
Provided, either one of the transmission lines and line corresponding means is in use
System, the other operates as a standby system, and external devices
Transmission of the active system based on control from
Transmission line and line correspondence means, and backup transmission line and line
Line-compatible switching equipment that can switch the correspondence with the corresponding means
Wherein the first line-corresponding means comprises a first transmission circuit.
A first interface unit for accommodating the line, and the first interface unit;
The main signal of the first transmission line accommodated in the interface unit is processed.
A first processing unit for processing and outputting, and a command from the external device.
The first interface unit and the
And controls the first processing unit and supports the second line.
A first switching control unit for switching control of the means.
The second line corresponding means is a second line accommodating the second transmission line.
2 interface section and the second interface section
Processes and outputs the main signal of the second transmission line accommodated in
A second processing unit, and a command or status determination from the external device.
The second interface unit and the second processing unit
And switching control of the first line corresponding means.
And a second switching control unit that performs switching.
The line-compatible switching device is provided with the first line-compatible means.
From the first interface unit to the first processing unit
And a second interface unit of the second line corresponding means.
Both of the above circuits between the path from
Main signal cross connection means for connecting between corresponding means
Means that the main signal confounding connection means is interposed, and the first transmission line
And operating the first line corresponding means as an active system,
Using the second transmission line and the second line corresponding means as a standby system
While in the non-operation state, the active system
And when switching the above line handling means of the standby system
Is the first line-handling method according to an instruction from an external device.
The first interface section of the stage remains active
Then, the first switching control unit and the first processing unit are brought into a non-operation state.
And the second interface unit of the second line corresponding means
The second processing unit and the second
The switching control unit is switched to an operation state. (C) In addition to the configuration of (B) the line-compatible switching device, the first
The first line terminating unit to the second line means.
Also has a second line terminating unit, which is used for the working system and the protection system.
When switching the line handling means, use an external device.
The second processing unit and the second switching control unit
A line pair that also activates the second line termination in conjunction with
Switching device. 2. The transmission line is an SDH line, the interface unit is an SDH interface circuit,
The processing unit is a cell processing circuit, the line interface switching system according to claim 1, characterized in providing a cell treated with this cell processing circuit in the cell switch.