JP2967766B2 - Optical communication network node - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical communication network node, and more particularly to an asynchronous transfer mode (Asynchr).
The present invention relates to an optical communication network node using an onus transfer mode (hereinafter referred to as ATM) technology and an optical wavelength division multiplexing technology.

[0002]

2. Description of the Related Art In recent years, along with the improvement of transmission bandwidth due to the progress of optical fiber transmission technology, expectations for a broadband ISDN (BISDN) that accommodates various communication services such as voice, data, and images in an integrated manner and provides them to subscribers. Is growing. ATM technology is an essential network technology for realizing this BISDN. ATM is described in, for example, the document "ATM-LAN" (Yoshi Shimizu and Hiroshi Suzuki, February 1995)
(Published on October 10th, issued by the Soft Research Center), all information is divided into fixed-length packets called cells, and a header necessary for routing is added to transmit the information.

In this case, a cell is transmitted to a target ATM node or an end by two kinds of logical connections of a virtual circuit and a virtual path.
A virtual circuit is a connection that is set up by allocating network resources (routes and bands) necessary for communication between a plurality of terminals by a signaling procedure each time a call is generated.

[0004] A virtual path is established between predetermined nodes in accordance with, for example, a demand forecast as to how much traffic can be expected between nodes such as exchanges and transmission devices in an ATM network, and a monitoring result of traffic actually transmitted. Is a logical transmission path that is set semi-fixed in advance. The virtual path is a connection independent of a network topology formed by actually connecting transmission paths such as optical fibers and coaxial cables. This virtual path accommodates a plurality of virtual circuits.

On the other hand, such a cell-based AT
Between M transmission / switching devices, high-speed cells are converted into optical signals and transmitted by the development of optical fiber communication technology. In recent years, in order to further increase the capacity of a network, 1
A wavelength division multiplexing type optical cross-connect device and an AT that multiplex and transmit a plurality of optical wavelengths in the optical fiber transmission line and switch the optical signal to another predetermined node as it is in the communication node.
Optical communication nodes combined with M devices are being studied.

Conventionally, such an optical communication node includes:
Firth Optoelectronics and Communications Conference Technical digest
oki Kato, and NaoyaHenmi,
“Optical Cross-connects
ystemusing Fixed-Wave len
gth Converterstobo Aid Wa
level Blocking ", First
Optoelectronics and Commu
notificationsCoference (OECC '
96) Technical Digest, PD1-
5, pp. 10-11, 1996).

FIG. 15 shows such an optical communication network node.

In the following description, sending a signal from a network constituted by optical communication network nodes to another network or device connected to the own node is referred to as "drop" for convenience. Conversely, sending a signal from another network or device connected to the own node to a network configured by an optical communication network node is called "insert". Further, "passing" means sending a signal from an adjacent optical communication network node to another optical communication network node in the network.
Call.

A wavelength division multiplexing / demultiplexing device 111 from a wavelength division multiplexing input optical transmission line 100-i (where i = 1 to M1, the same applies hereinafter)
After being demultiplexed into optical signals having n different wavelengths at 0-i,
Input to optical switch network 1130.

The optical switch network 1130 converts an optical signal from the wavelength division multiplexer 1110-i into a predetermined wavelength converter 11
40-i.n or the receiving interface 1160-
j (where j = 1 to M2, the same applies hereinafter).

Wavelength converter 1140- (i-n-n + 1)
.About.1140-in each fixedly converts the wavelength of the input optical signal to .lambda.1 to .lambda.n.

The wavelength multiplexer 1111-i multiplexes the optical signals from the wavelength converters 1140- (1.n-n + 1) to 1140-i.n, and respectively outputs the wavelength multiplexed output optical transmission line 1150.
-Send to i.

On the other hand, cells of the optical signal from the optical switch network 1170 are respectively connected to the receiving interface 1160-k.
(Where k = 1 to L, the same applies hereinafter), the signal is once converted into an electric signal cell, and then sent to the ATM switch 1170.
The cell of the optical signal from the input optical transmission line 180-k is
Each of them is once converted into an electric signal cell again by the reception interface 1161-k, and then the ATM switch 1170
Sent to.

The ATM switch 1170 exchanges the cell of the input electric signal to a predetermined transmission interface 1162-j or 1163-k according to the header and outputs the cell.

The switched electric signal cells are converted to optical signal cells by the transmission interface 1162-j, and then sent to the optical switch network 1130.

The optical switch network 1130 also sends cells of the optical signal from the transmission interface 1162-j to a predetermined wavelength converter 1140-1 to 1140-M1.n or the reception interface 1160-j.

The switched electric signal cells are converted into optical signal cells by the transmission interface 1163-j, and then sent to the output optical transmission line.

As described above, conventionally, a cell multiplexed with an optical signal of an arbitrary wavelength transmitted on an arbitrary wavelength multiplexed input optical transmission line 100-i is dropped on an arbitrary output optical transmission line 190-k. Can be. Further, the optical communication network node shown in FIG.
-K can be converted into an optical signal of an arbitrary wavelength and inserted into an arbitrary wavelength multiplexed output optical transmission line 1150-i.

Furthermore, the optical communication network node shown in FIG.
By converting a cell multiplexed with an optical signal of an arbitrary wavelength transmitted by i into an optical signal of an arbitrary wavelength and inserting it into an arbitrary wavelength multiplexing output optical transmission line 1150-i, a wavelength multiplexing input optical transmission line 100-i and wavelength multiplexed output optical transmission line 1
It is also possible to carry out the passage of signals between 150-i.

[0020]

The above-described conventional optical communication network node includes signal drop, insert,
Further passages can be made. However, this conventional technique has the following disadvantages.

First, in the above-described prior art, the wavelength multiplexing input optical transmission line 100-i and the wavelength multiplexing output optical transmission line 1
Two overlapping methods are used for wavelength conversion between 150-i and passing of an arbitrary optical signal. That is, the optical switch network 1130 and the wavelength converter 1140-
1 to 1140-M1.n, an optical signal from the optical switch network 1130 is converted into an electric signal, and then switched by the ATM switch 1170. The optical switch network 1130 and the wavelength converter 1140-1 are switched again. ~ 1140-
And a method of realizing via M1 · n.

Accordingly, a large-scale optical switch network is required, and it is difficult to reduce the size and cost of the node. Specifically, in FIG. 15, the wavelength multiplexing input optical transmission line 100-i and the input optical transmission line 180-
In order that any signal on k can be output from any of the wavelength multiplexed output optical transmission line 1150-i and the output optical transmission line 190-k, M2 = (M1 · n), and (2 · M1 ·
n) The number of cross points is ^{two and the} optical switch network 113
Required for 0.

In addition, since the above two methods overlap, a large-capacity ATM switch is required, and it is difficult to reduce the size and cost of the node. Specifically, in FIG. 15, under the same conditions as above, the AT
The M switch 1170 is connected to the wavelength multiplexed input optical transmission line 100-i.
In order to switch the signal from the input optical transmission line 180-k and (M2 + L) ² = (M1 · n + L) ^{2, the} number of cross points is required.

Further, in the above-mentioned prior art, the optical switch network 1130 and the ATM switch 1170 are configured as a hybrid. Therefore, both the optical switch network 1130 and the self-routing switch of the ATM switch 1170 are not realized simultaneously by one high-speed broadband switch. Therefore, under the same conditions as above in FIG. 15, the number of crosspoints of (2 · M1 · n) ² is necessary for the optical switch network 1130, and (M1
・ N + L) The number of cross points of ² is the ATM switch 11
Required for 70. That is, the optical switch network and A
Since a high-speed broadband switch is used for both of the TM switches, there is a disadvantage that it is difficult to reduce the size and cost of the node.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks of the prior art, and has an object to reduce the required number of crosspoints in an optical switch network or the required capacity of an ATM switch. It is to provide an optical communication network node which can be implemented.

[0026]

An optical communication network node according to the present invention comprises: first optical branching means for branching an optical signal having an arbitrary wavelength among wavelength-multiplexed wavelength-division multiplexed optical signals ; Any of the signals after branching by the optical branching means
Second optical branching means for further branching an optical signal having a desired wavelength;
The signal after branching by the second optical branching means is input.
Having an input terminal and a plurality of output terminals;
To a desired one of the plurality of output terminals.
ATM switch and external input signal input from outside
And an input terminal having a first input and a plurality of output terminals.
Terminal input to the desired one of the plurality of output terminals.
A second ATM switch for outputting the second ATM switch;
Switch output from the first optical splitting means.
Second light insertion means for joining the first light
A signal between the signal branched by the branching means and the external input signal.
It is characterized by including switching means for performing switching, and first optical insertion means for joining a signal after switching by the switching means to the wavelength multiplexed signal.

Another optical communication network according to the present invention
Is a plurality of first input optical signals to which the wavelength multiplexed optical signal is input.
A transmission path, a plurality of second input optical transmission paths, and a wavelength division multiplexed optical signal.
A plurality of first output optical transmission line No. is output, a plurality of second
2 output optical transmission lines, a plurality of first input terminals and a plurality of second
Input terminals, a plurality of first output terminals, a plurality of second output terminals,
Having a plurality of wavelengths incident from the first input end.
The optical signal of a desired wavelength in the heavy optical signal is
Output to one of an output terminal and a second output terminal,
In a plurality of wavelength multiplexed optical signals incident from the second input terminal
Output to the plurality of first output terminals.
Optical add / drop circuit, and a plurality of input terminals and a plurality of output terminals.
Having a desired wavelength between the plurality of input terminals and the output terminal.
1 and 2 for converting the optical signal of
Optical switch network and a plurality of input terminals and output terminals.
Input from any input terminal of the plurality of input terminals.
ATM cells to be output are sent to the plurality of output terminals according to the header.
An ATM switch for outputting to a predetermined output terminal ;
An input end and a plurality of output ends, wherein the one input end
The wavelength-division multiplexed optical signal to be input is converted into a plurality of
After converting these optical signals into electrical signals
The ATM cells extracted from the transmission frame are
Multiple wavelength multiplex reception interfaces output from each of the output terminals
And one input terminal and one output terminal.
After converting the optical signal incident from the input end into an electrical signal
The ATM cell extracted from the transmission frame is sent to the output terminal
Output interfaces and input terminals
And one output terminal, and input from the plurality of input terminals.
ATM cells are stored in the transmission frame, and the
After converting to an optical signal, the wavelength
A plurality of wavelength multiplex transmissions for emitting heavy light signals from the output end
Interface and one input and one output
And transmits the ATM cell input from the input terminal to the transmission frame.
Output from the output end after being stored in the
And a plurality of transmission interfaces ,
The plurality of first input optical transmission lines are connected to the optical add / drop circuit.
A second input terminal connected to a first input terminal ;
Each of the output ends is connected to a plurality of inputs of the first optical switch network.
A plurality of the first optical switch networks connected to the
Each of the output terminals is provided with the plurality of wavelength multiplex reception interfaces.
A plurality of second input optical transmissions connected to respective inputs;
Each of the paths is connected to an input end of the plurality of receiving interfaces.
Connected to a plurality of outputs of the wavelength multiplex reception interface.
Terminal and the output terminal of the receiving interface
Connected to the input terminal of the M switch ,
An output terminal is connected to a plurality of inputs of the wavelength multiplex transmission interface.
Connected to each end and the input end of the transmission interface.
Is, the plurality of wavelength division multiplexing transmission interface each output
One end of each of a plurality of input ends of the second optical switch network
Connected to a plurality of outputs of the second optical switch network.
One end is connected to each of the second input ends of the optical add / drop circuit.
It is, first the first output end of the optical add drop circuit of the plurality
Connected to one output optical transmission line and connected to the plurality of transmission interfaces.
Output end of each of the plurality of second output optical transmission lines.
Is connected to the terminal.

Another optical communication network according to the present invention
Is a plurality of first input optical signals to which the wavelength multiplexed optical signal is input.
A transmission path, a plurality of second input optical transmission paths, and a wavelength division multiplexed optical signal.
A plurality of first output optical transmission line No. is output, a plurality of second
2 output optical transmission lines, a plurality of first input terminals and a plurality of second
Input terminals, a plurality of first output terminals, a plurality of second output terminals,
Having a plurality of wavelengths incident from the first input end.
The optical signal of a desired wavelength in the heavy optical signal is
Output to one of an output terminal and a second output terminal,
In a plurality of wavelength multiplexed optical signals incident from the second input terminal
Output to the plurality of first output terminals.
First and second optical add / drop circuits, and a plurality of input terminals.
A plurality of output terminals, between the plurality of input terminals and the output terminal
Converts an optical signal of a desired wavelength into an optical signal of an arbitrary wavelength
First and second optical switch networks, and a plurality of input terminals;
Having a number of output terminals, and input from the plurality of input terminals.
The ATM cell is transmitted to a predetermined one of the output terminals according to the header.
The first to third ATM switch for outputting the output end, one
Having one input terminal and a plurality of output terminals.
Wavelength multiplexed optical signals input from multiple
And converted these optical signals into electrical signals.
ATM cells to be later taken out of the transmission frame
Multiple wavelength multiplexing reception interfaces output from each of the
Face, one input end and one output end,
After converting the optical signal incident from the input end to an electrical signal
At the output terminal.
From multiple receiving interfaces and multiple inputs from
An end and one output end, and input from the plurality of input ends.
After storing the ATM cells to be transmitted in the transmission frame,
Converts to optical signals with different wavelengths and combines them to generate a wavelength
A plurality of wavelength division multiplex transmissions for multiplexing optical signals from the output end;
Communication interface, one input terminal and one output terminal
And transmits ATM cells input from the input terminal.
After being stored in the camera, it is converted to an optical signal and emitted from the output end.
And a plurality of transmission interfaces ,
The plurality of first input optical transmission lines are connected to the first optical add / drop multiplexer.
A first optical drop-and-insert connected to a first input of a circuit;
Each of a second output of the circuit is the first optical switch circuit
A first optical switch connected to a plurality of input terminals of the network;
Each of a plurality of output ends of the network is the second optical add / drop circuit
And the second optical add / drop circuit connected to the first input terminal of the
Each of the second output terminals of the plurality of
Is connected to the input end of the face each of the plurality of second input
Each of the optical transmission lines is an input of the plurality of receiving interfaces.
It is connected to the force end, multiple of the wavelength multiplexing receiving interface
Output terminals are each connected to an input terminal of the first ATM switch.
Connected and the output end of the receiving interface is connected to the second
Input terminal of the ATM switch and the third ATM switch
And the output terminal of the second ATM switch.
A power terminal and an output terminal of the first ATM switch are connected to the transmitting end.
The third ATM connected to the input end of the interface;
The output terminal of the switch is
A plurality of wavelength division multiplex transmissions connected to each of a plurality of input terminals;
The output terminal of each interface is the second optical add / drop circuit.
The second optical branch connected to each of the second input ends of the path
A first output terminal of the insertion circuit is the second optical switch network;
And the second optical switch is connected to each of a plurality of input terminals of the second optical switch.
A plurality of output terminals of the first optical add / drop circuit.
A first optical drop-and-insert connected to each of the second input ends;
A first output terminal of the circuit is connected to the plurality of first output optical transmission lines.
Connected and the output ends of the plurality of transmission interfaces are forward
Connected to each of the plurality of second output optical transmission lines.
And features.

Another optical communication network according to the present invention
Is a plurality of first input optical signals to which the wavelength multiplexed optical signal is input.
A transmission path, a plurality of second input optical transmission paths, and a wavelength division multiplexed optical signal.
A plurality of first output optical transmission line No. is output, a plurality of second
2 output optical transmission lines, a plurality of first input terminals and a plurality of second
Input terminals, a plurality of first output terminals, a plurality of second output terminals,
Having a plurality of wavelengths incident from the first input end.
The optical signal of a desired wavelength in the heavy optical signal is
Output to one of an output terminal and a second output terminal,
In a plurality of wavelength multiplexed optical signals incident from the second input terminal
Output to the plurality of first output terminals.
Optical add / drop circuit, and one input terminal and a plurality of output terminals
Wavelength multiplexed optical signal incident from the one input end
After demultiplexing the signal into optical signals with different wavelengths,
A plurality of optical signals are output as light from each of the plurality of output terminals.
Emitting, or converting the plurality of optical signals into electrical signals
Temporary buffer of ATM cells extracted from transmission frame
ATM cell header stored in the buffer and output from the buffer
After processing, each of the plurality of output terminals is converted to an optical signal.
A plurality of wavelength-division multiplex receiving interfaces emitting from each;
It has one input terminal and one output terminal, from the input terminal
Converts the incoming optical signal into an electrical signal and converts it into a transmission frame.
Optical signal after processing the header of the ATM cell taken out
And a plurality of reception interfaces for converting the
And a plurality of input terminals and one output terminal.
Optical signals on optical lines input from multiple input terminals
Alternatively, it is converted to an optical signal of a predetermined wavelength, or the optical signal is
ATM cells converted to electrical signals and extracted
Either convert to the predetermined wavelength after storing in
After performing one, the plurality of wavelengths converted to the predetermined wavelength
Combines optical signals and emits wavelength-multiplexed optical signals from the output end
Multiple wavelength multiplexing transmission interfaces and one input
Having one end and one output end, input from the input end
The optical signal is converted to an electrical signal and transmitted through the ATM cell.
After being stored in the transmission frame, it is converted into an optical signal and
Outgoing interfaces and outgoing inputs
An end and a plurality of output ends, and the plurality of predetermined input ends.
Whether to set the predetermined optical line between the output end
Or said plurality of wavelength multiplexing receiving interface, receiving
Optical signals are exchanged for each cell under the control of the communication interface.
That the optical switching network is configured to include a plurality of
A first input optical transmission line connected to a first input of the optical add / drop circuit;
And each of the second output terminals of the optical add / drop circuit is connected to
Each of the plurality of wavelength multiplex reception interfaces
And each of the plurality of second input optical transmission lines is connected
It is connected to an input terminal of said plurality of receiving interface, before
Each of the multiple output ends of the wavelength division multiplex receiving interface
The output end of the receiving interface is the optical switch circuit;
Connected to the input of the network, the output of said optical switch network
Each end has a plurality of input ends of the WDM transmission interface.
Connected people and to the input end of the transmission interface, wherein
The output end of each of the plurality of wavelength multiplex transmission interfaces is
Is connected to each of the second input end of the optical add-drop circuit, the
A first output terminal of the optical add / drop circuit is connected to the plurality of first outputs;
Connected to an optical transmission line, and
An output end is connected to each of the plurality of second output optical transmission lines.
It is characterized by having been.

In short, according to the present invention, an optical signal of an arbitrary wavelength of the wavelength multiplexed wavelength multiplexed optical signal is branched and then switched with an external input signal, and the switched signal is combined with the wavelength multiplexed signal. As a result, the number of cross points required for the optical switch network can be reduced, and the size and cost of the node can be reduced.

[0031]

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an optical communication network node according to the first embodiment of the present invention. 15, the same parts as those in FIG. 15 are indicated by the same reference numerals, and the detailed description of the parts will be omitted.

The network node shown in FIG. 1 has a wavelength multiplexed input optical transmission line 100-x (where x = 1 to 4).
M, the same applies hereinafter) and the input optical transmission line 180-y (where y
= 1 to L, the same applies hereinafter) and the wavelength multiplexed output optical transmission line 120
-X, an output optical transmission line 190-y, and an optical signal of a desired wavelength among the wavelength-multiplexed optical signals input from the wavelength-multiplexed input optical transmission line 100-x. An optical signal having a desired wavelength among a plurality of wavelength-division multiplexed optical signals input from the intra-node optical transmission line 133-x is output to one of the intra-node optical transmission lines 130-x. -Optical add / drop circuit 110 for emitting light to x
An optical switch network 140 for converting an optical signal of a desired wavelength into an optical signal of an arbitrary wavelength between the intra-node optical transmission lines 130-x and 131-x; and an intra-node optical transmission line 132-x
And an optical switch circuit 141 for converting an optical signal of a desired wavelength into an optical signal of an arbitrary wavelength between the optical transmission line 133-x and a wavelength-division multiplexed optical signal input from the intra-node optical transmission line 131-x. A wavelength-division multiplexing receiving interface 150-x for outputting an ATM cell from each of a plurality of output terminals after demultiplexing into a plurality of different optical signals and converting them into electric signals;
A receiving interface 152-y which outputs an ATM cell after converting an optical signal incident from 80-y into an electric signal.
The ATM cells input from the wavelength multiplexing reception interface 150-x and the reception interface 152-y are transmitted to the wavelength multiplexing transmission interfaces 150-x and 1 according to the header.
The ATM switch 170 that outputs to the 53-y and the ATM cell that is input from the ATM switch 170 are converted into optical signals having different wavelengths and multiplexed, and then the wavelength multiplexed optical signal is output to the intra-node optical transmission line 132-x. It comprises a wavelength multiplexing transmission interface 151-x and a transmission interface 153-y for converting an ATM cell input from the ATM switch 170 into an optical signal and then outputting the optical signal to an output optical transmission line 190-y.

The optical add / drop circuit 110 receives a wavelength-division multiplexed optical signal from the wavelength-division multiplexed input optical transmission line 100-x, and passes the wavelength-division multiplexed output optical transmission line 120-
Send to x. The optical add / drop circuit 110 receives the wavelength multiplexed optical signals from the wavelength multiplexed input optical transmission line 100-x and drops them to the intra-node optical transmission line 130-x. As described above, the optical add / drop circuit 110 converts the optical signal on the wavelength multiplexed input optical transmission line 100-x into an optical signal without switching the wavelength and the output path (the wavelength multiplexed output optical transmission line 120-x). Is used when passing through. Further, the optical add / drop circuit 110 can be used as a wavelength division multiplexing / demultiplexing function required for performing maintenance, operation, and management of optical signals on the wavelength division multiplexing input optical transmission line 100-x for each optical signal having a different wavelength. .

When the dropped multiplexed optical signal from the intra-node optical transmission line 130-x is input, the optical switch network 140 converts the optical signal of a predetermined wavelength of the intra-node optical transmission line 130-x into an optical signal. , And converts the signal into an optical signal having a desired wavelength, and outputs the signal to a desired intra-node optical transmission line 131-x.

The wavelength-division multiplexed optical signals output from the optical switch network 140 are sent to the wavelength-division multiplexing reception interfaces 150-x via the intra-node optical transmission lines 131-x.

Each of the wavelength division multiplexing reception interfaces 150-x has input ports 160- (xn-n + 1) to 16
It is connected to the ATM switch 170 by n units of 0-x · n. Each of the wavelength division multiplexing receiving interfaces 150-x demultiplexes an input wavelength division multiplexed optical signal into optical signals of n wavelengths, then extracts an ATM cell from a transmission frame for each of the n optical signals, and 160- (xn-n
+1) to 160-x · n to send the cell to the ATM switch 170.

On the other hand, each of the receiving interfaces 152-y takes out the ATM cells from the transmission frame after receiving the optical signal from the input optical transmission line 180-y, and outputs the ATM cells via the input ports 161-1 to 161-1M. Switch 17
Send 0 cells.

The ATM switch 170 is connected to the input port 160
-1 to 160-M · n and predetermined output ports 162-1 to 162 according to the header of the cell input from 161-y
-Mn and 163-y switch every cell.

Each of the wavelength division multiplexing transmission interfaces 151-x also has an output port 162- (x · n−n + 1) to
It is connected to the ATM switch 170 by n units of 162-x · n. WDM transmission interface 151-x
Are output ports 162- (x · n−n + 1) to 1
A cell input from the ATM switch 170 via 62-x · n is inserted into the transmission frame every n cells, converted into optical signals of n wavelengths, and multiplexed to generate a wavelength multiplexed optical signal. It is sent to the switch network 141.

When a wavelength multiplexed optical signal is input from the wavelength multiplexing transmission interface 151-x via the intra-node optical transmission line 132-x, the optical switch network 141 receives a predetermined signal from the intra-node optical transmission line 132-x. The optical signal having the desired wavelength is converted into the optical signal having the desired wavelength, and the optical transmission line 1 within the desired node is converted.
Output to 33-x.

The optical add / drop circuit 110 inputs the wavelength multiplexed optical signals from the intra-node optical transmission line 133-x and inserts them into the wavelength multiplexed output optical transmission line 120-x. ―
On the other hand, each of the transmission interfaces 153-y inserts a cell input from the ATM switch 170 via the output port 163-y into a transmission frame, converts the cell into an optical signal, and sends the signal to an output optical transmission line 190-y.

FIG. 2 shows a detailed configuration of the optical add / drop circuit 110 in FIG.

In the figure, the optical add / drop circuit 110 comprises:
The wavelength multiplexing input optical transmission line 100-x and the input terminal 2 in FIG.
10-x are connected to each other, the wavelength multiplexed output optical transmission line 120-x and the output terminal 270-x in FIG. 1 are respectively connected, and the intra-node optical transmission line 130-x and the output terminal 2 in FIG.
80-x, and the intra-node optical transmission line 133-x in FIG. 1 and the input terminal 290-x are connected to each other.

Each of the wavelength division multiplexed signals input from the input terminal 210-x is split by the optical splitter 220-x into a wavelength division multiplexer 230-x and an output terminal 280-x.

The wavelength division multiplexer 230-x is connected to the
The wavelength division multiplexed signal from 20-x is demultiplexed into n wavelengths, and each is transmitted to optical gate elements 240-1 to 240-M · n.

Optical gate elements 240-1 to 240-M · n
When the input optical signal of a predetermined wavelength is passed through the output terminal 270-x as it is, the wavelength multiplexer 250
-Output to x. Alternatively, optical gate elements 240-1 and 240-2
40-M · n is an output terminal 280 which does not allow an input optical signal of a predetermined wavelength to pass through the output terminal 270-x as it is.
-When dropping to x, the passage of the optical signal is blocked.

Each of the wavelength multiplexers 250-x multiplexes the optical signals passing through the optical gate elements 240-1 to 240-M · n, and outputs the multiplexed signals to the optical multiplexer 260-x.

Each of the optical multiplexers 260-x merges the wavelength multiplexed signal from the wavelength multiplexer 250-x with the wavelength multiplexed signal inserted from the input terminal 290-x, and sends out to the output terminal 270-x. .

As described above, an arbitrary wavelength λz multiplexed by the optical add / drop circuit 110 shown in FIG. 2 on the wavelength multiplexed signal input from the input terminal 210-x.
(Where z = 1 to n, the same applies hereinafter) are output to output terminals 270-x or input terminals 210-x, respectively.
Any wavelength λ multiplexed on the wavelength multiplexed signal input from
z optical signals are respectively dropped to output terminals 280-x,
Further, an optical signal of an arbitrary wavelength λz multiplexed with the wavelength multiplexed signal input from the input terminal 290-x can be inserted into the output terminal 270-x.

The detailed configuration of the optical switch network 140 in FIG. 1 is shown in FIG.

In the same figure, the optical switch network 140
Is the optical transmission line 130-x in the node and the input terminal 3 in FIG.
10-x, and the intra-node optical transmission line 131-x and the output terminal 370-x in FIG. 1 are connected.

The optical switch network 141 has a similar configuration. In the case of the optical switch network 141, the intra-node optical transmission line 132-x and the input terminal 310-x in FIG. 1 are respectively connected, and the intra-node optical transmission line 133-x and the output terminal 370- in FIG. x are connected to each other.

Each of the optical splitters 320-x is connected to the input terminal 31.
The wavelength-division multiplexed signal from 0-x is split into M · n wavelength-division multiplexed signals, each of which is an optical switch 330-1 to 330-M · n
Send to

Optical switch 330- (xn-n + 1)-
The 330-x · n selects one of the M wavelength-division multiplexed signals from the optical splitter 320-x and selects a variable wavelength filter 340-x.
(X · n−n + 1) to 340−x · n.

Variable wavelength filter 340- (xn-n +
1) to 340-x · n select an optical signal of a desired wavelength from the input wavelength multiplexed signal, and
• n−n + 1) to 350−x · n.

Wavelength converter 350- (xn-n + 1)-
350-x · n fixedly converts the wavelength of the input optical signal to a predetermined wavelength λz. Wavelength converter 350
-The optical signals wavelength-converted by (xn-n + 1) to 350-xn are combined by the optical combiner 360-x, and the wavelength multiplexed signal from the optical combiner 360-x is output to the output terminal 370-.
x, respectively.

As described above, the optical switch network 110 shown in FIG.
An optical signal of an arbitrary wavelength λz multiplexed on a wavelength multiplexed signal input from -x can be exchanged for an optical signal of an arbitrary wavelength λz multiplexed on a wavelength multiplexed signal of an arbitrary output terminal 370-x. .

The details of the optical switch network shown in FIG. 3 are described in a known document (M. Nisio and S.A.).
Suzuki, “Photonic Wavelen
gth-Division Switching Ne
work Using a Parallel λ-s
switch ”, Springer series
Electronics and photonic
s, vol. 29, Photonic Switch
ing II, Editor: K. Tada,
H. S. Hinton, pp. 287, 1990. )
It is described in.

The wavelength multiplex receiving interface 15 in FIG.
0-x, the detailed configuration of the wavelength multiplexing transmission interface 151-x is shown in FIGS.

First, as shown in FIG. 4, in the wavelength division multiplexing receiving interface 150-x, the intra-node optical transmission line 131-x and the input terminal 410 in FIG.
Input port 160- (x · n−n) of TM switch 170
+1) to 160-x.n are connected to the output terminal 450-x.

The wavelength division multiplexing / demultiplexing device 420 shown in FIG. 6 demultiplexes the wavelength multiplexing signal from the input terminal 410 into n wavelength optical signals and sends them to the photoelectric converter 430-z.

The optical-electrical converter 430-z temporarily converts the optical signal of each predetermined wavelength λz from the wavelength division multiplexer into an electric signal, and outputs the electric signal to the cell extracting circuit 440-z.

Each of the cell extracting circuits 440-z receives an electric signal from the photoelectric converter 430-z, extracts a cell from the transmission frame, and sends the cell to the output terminal 450-z.

In this way, the wavelength division multiplexing reception interface 150-x converts the n optical signals multiplexed into the wavelength division multiplexed signal from the input terminal 410 into electric signals, then extracts cells from the transmission frame and outputs the cells. Terminal 450-
Output to x.

On the other hand, as shown in FIG. 5, the wavelength multiplexing transmission interface 151-x is connected to the output port 162- (x · n−n + 1) of the ATM switch 170 in FIG.
162-x · n are connected to the input terminal 411-z, and the intra-node optical transmission line 132-x and the output terminal 451 are connected. Each of the cell insertion circuits 421-z inputs cells from the input terminal 411-z, inserts them into a transmission frame, and sends them to the electro-optical converter 431-z.

The electro-optical converter 431-z is connected to the cell insertion circuit 4
The electric signals from 21-x are converted into optical signals having predetermined wavelengths, respectively, and output to the wavelength multiplexer 441.

The wavelength multiplexing device 441 is connected to the electro-optical converter 43.
The optical signals of n wavelengths from 1-z are multiplexed, and the wavelength-division multiplexed signal is transmitted to the output terminal 451.

As described above, the wavelength multiplexing transmission interface 151-x inserts the cell from the input terminal 411-z into the transmission frame, converts the cell into an optical signal of a predetermined n wavelengths, and multiplexes the wavelength. The wavelength multiplexed signal is output to the output terminal 451.

The detailed configurations of the receiving interface 152 and the transmitting interface 153 in FIG. 1 are shown in FIGS.

As shown in FIG. 6, the receiving interface 152 has the input optical transmission line 180-y and the input terminal 510 in FIG. 1 connected to each other, and each of the input ports 161-y of the ATM switch 170 is connected to each other. It is connected to the output terminal 540. The photoelectric converter 520 once converts the optical signal from the input terminal 510 into an electrical signal, and
Output to

The cell take-out circuit 530 includes the photoelectric converter 5
An electric signal from the terminal 20 is input, a cell is extracted from the transmission frame, and the cell is sent to the output terminal 540.

In this way, the receiving interface 152
Converts the optical signal from the input terminal 510 into an electric signal, extracts the cell from the transmission frame, and
Output to 40.

On the other hand, as shown in FIG. 7, the transmission interface 153 has an output port 163-y of the ATM switch 170 shown in FIG. 1 connected to the input terminal 511, and an output optical transmission line 190-y. The output terminal 541 is connected. The cell insertion circuit 521 receives cells from the input terminal 511 and inserts them into the transmission frame.
It is sent to the electro-optical converter 531.

The electro-optical converter 531 includes a cell insertion circuit 521
Is converted into an optical signal and transmitted to an output terminal 541.

Thus, the transmission interface 153
Outputs the cell from the input terminal 511 to the output terminal 541 after inserting the cell into the transmission frame and converting it into an optical signal.

As described above, the optical communication network node according to the first embodiment of the present invention shown in FIG. 1 has the arbitrary wavelength transmitted through the arbitrary wavelength multiplex input optical transmission line 100-x. Can be dropped to any output optical transmission line 190-y.

The optical communication network node shown in FIG. 1 converts a cell from an arbitrary input optical transmission line 180-y into an optical signal of an arbitrary wavelength to output an arbitrary wavelength multiplexed output optical transmission line 120. -Can be inserted into x.

Further, the optical communication network node shown in FIG.
By converting a cell multiplexed with an optical signal of an arbitrary wavelength transmitted by x into an optical signal of an arbitrary wavelength and inserting it into an arbitrary wavelength multiplexing output optical transmission line 120-x, a wavelength multiplexing input optical transmission line 100-x and wavelength multiplexed output optical transmission line 12
Pass signals between 0-x.

The optical communication network node shown in FIG. 1 converts the wavelength multiplexed optical signals transmitted through the wavelength multiplexed input optical transmission line 100-x into the wavelength multiplexed output optical transmission line 1 respectively.
20-x can be passed without conversion of the wavelength.

Here, the first embodiment of the present invention shown in FIG.
The required scales of the optical communication network node according to the embodiment and the conventional optical communication network node will be compared. However, it is assumed that all traffic transmitted through the wavelength multiplexing input transmission line 100-x and the wavelength multiplexing output optical transmission line 120-x can be dropped or inserted.

The optical communication network node shown in FIG. 1 includes an optical add / drop circuit 110 and an optical switch network 14.
When 0 and 141 are analyzed by a space division equivalent circuit, (2 ·
(M · n) ² + (M · n) cross points are required. On the other hand, since the conventional optical communication network node shown in FIG. 11 has M1 = M, the optical switch network 1130 needs (2 · M · n) ² cross points. The number of cross points required for the ATM switch 170 is the same in the configuration of FIG. 1 and the conventional configuration.
Therefore, the optical communication network node shown in FIG. 1 can reduce the number of required cross points of the optical switch network and reduce the size as compared with the related art.

FIG. 8 shows an optical communication network node according to the second embodiment of the present invention.

The optical communication network node shown in the figure has a wavelength multiplexed input optical transmission line 600-x, an input optical transmission line 680-y, and a wavelength multiplexed output optical transmission line 620-x.
And an output optical transmission line 690-y and an optical signal of a desired wavelength among the wavelength-multiplexed optical signals input from the wavelength-multiplexed input optical transmission line 600-x, The signal is output to one of the optical transmission lines 630-x, and an optical signal having a desired wavelength among a plurality of wavelength-multiplexed optical signals incident from the intra-node optical transmission line 635-x is output to the wavelength-multiplexed output optical transmission line 620-x. An optical add / drop circuit 610 that emits light to a node, an optical switch network 640 that converts an optical signal of a desired wavelength into an optical signal of an arbitrary wavelength between the intra-node optical transmission lines 630-x and 631-x, Internal optical transmission lines 632-x and 63
An optical switch network 641 for converting an optical signal of a desired wavelength into an optical signal of an arbitrary wavelength between 5-x and an optical signal of a desired wavelength in a wavelength-division multiplexed optical signal incident from the intra-node optical transmission line 631-x. Is output to either the wavelength-division multiplexed output optical transmission line 632-x or the intra-node optical transmission line 633-x, and a plurality of wavelength-multiplexed optical signals incident from the intra-node optical transmission line 634-x are output. An optical add / drop circuit 611 for emitting an optical signal of a desired wavelength in the wavelength multiplexed output optical transmission line 632-x.
And wavelength division multiplexing for demultiplexing a wavelength-division multiplexed optical signal input from the intra-node optical transmission line 633-x into a plurality of optical signals having different wavelengths, converting the demultiplexed optical signal into an electrical signal, and outputting an ATM cell from each of the plurality of output terminals A receiving interface 650-x, a receiving interface 652-y for outputting an ATM cell after converting an optical signal incident from the input optical transmission line 680-y into an electric signal, and a wavelength multiplexing receiving interface 650-x
ATM switch 670 that outputs an ATM cell input from the interface to transmission interface 653-y according to the header
And the AT input from the receiving interface 652-y
The transmission interface 653-y transmits the M cell according to the header.
Switches 672 and 671 for switching to the transmission interface 651-x, and ATM cells input from the ATM switch 671 are converted into optical signals having different wavelengths and multiplexed, and then the wavelength-division multiplexed optical signal is converted into the optical transmission path 634 within the node.
-X wavelength multiplexing transmission interface 651-x
And A input from ATM switches 670 and 672
After converting the TM cell into an optical signal, the output optical transmission line 690-
and a transmission interface 653-y emitting from y.

The optical add / drop circuit 610 receives a wavelength division multiplexed optical signal from the wavelength division multiplexed input optical transmission line 600-x, and passes the wavelength division multiplexed optical signal when passing therethrough.
Send to x. Further, the optical add / drop circuit 610 receives the wavelength multiplexed optical signals from the wavelength multiplexed input optical transmission line 600-x and drops them to the intra-node optical transmission line 630-x.

As described above, the optical add / drop circuit 610 has the configuration shown in FIG.
In the same manner as the optical add / drop circuit 110, the optical signal on the wavelength-division multiplexed input optical transmission line 600-x is converted into a wavelength and an output path (the wavelength-division multiplexed output optical transmission line 620-x is not switched and this node Further, the optical add / drop circuit 610 is used for maintaining, operating, and managing the optical signals on the wavelength-division multiplexed input optical transmission line 600-x for each optical signal having a different wavelength. It can also be used as a separation function.

When the dropped wavelength-division multiplexed optical signal is input from the intra-node optical transmission line 630-x, the optical switch network 640 converts the optical signal of a predetermined wavelength of the intra-node optical transmission line 630-x into an optical signal. The signal is converted into an optical signal of a desired wavelength and output to a desired intra-node optical transmission line 631-x.

The wavelength multiplexed optical signal output from the optical switch network 640 is input to the optical add / drop circuit 611 via the intra-node optical transmission line 631-x.

The optical add / drop circuit 611 receives a wavelength multiplexed optical signal from the intra-node optical transmission line 631-x, and sends it out to the intra-node optical transmission line 632-x when passing these signals.

The optical add / drop circuit 611 receives the wavelength multiplexed optical signals from the intra-node optical transmission line 631-x, and drops them to the intra-node optical transmission line 633-x.

The wavelength-division multiplexed optical signals dropped from the optical add / drop circuit 611 are sent to the wavelength-division multiplex reception interface 650-x via the intra-node optical transmission lines 633-x. As described above, the optical add / drop circuit 611 passes a plurality of wavelength-division multiplexed signals from the optical switch network 640 to the optical switch network 641 as light without intervening the ATM switches 670 to 672.

Each of the wavelength division multiplex receiving interfaces 650-x has input ports 660- (xn-n + 1) to 66
It is connected to the ATM switch 670 by n units of 0-x · n.

Each of the wavelength division multiplexing receiving interfaces 650-x separates the input wavelength division multiplexed optical signal into optical signals of n wavelengths, and then extracts the ATM cells from the transmission frame for each of the n optical signals. , Input port 660- (xn-
ATM switch 670 via (n + 1) -660-xn
Send Hessel.

The ATM switch 670 is connected to the input port 66
Switching is performed for each predetermined output port 661-y in accordance with the header of the cell input from 0-1 to 660-M · n.

On the other hand, each of the receiving interfaces 652-y receives the optical signal from the input optical transmission line 680-y, and then switches from the input port 662-y or the input port 663-y via the distributor 601-y. 672, 67
Send one cell.

The ATM switch 671 is connected to the input port 66
Switching is performed for each cell to a predetermined output port 664-y according to the header of the cell input from 3-y.

Output port 661 of ATM switch 670
-Cell from y and output port 6 of ATM switch 672
The cells from 65-y are each sent out to the transmission interface 653-y via the merger 602-y.

Each of the transmission interfaces 653-y
After each cell input via the merger 602-y is inserted into the transmission frame, the cell is converted into an optical signal, and the output optical transmission line 690
Send to y.

The ATM switch 672 is connected to the input port 66
A predetermined output port 665-y is switched for each cell according to the header of the cell input from 2-y.

Each of the wavelength division multiplexing transmission interfaces 651-x has output ports 664- (x · n−n + 1) to 66
The switch is connected to the ATM switch 671 by N units of 4-x · n.

Each of the wavelength division multiplexing transmission interfaces 651-x has an output port 664- (xn-n + 1) to 66
The cell input from the ATM switch 671 via 4-x · n is inserted into the transmission frame every n cells, converted into optical signals of n wavelengths, and then combined to generate an optical transmission path in the node. At 634-x, the wavelength multiplexed optical signal is inserted into the optical add / drop circuit 611.

The optical add / drop circuit 611 receives the wavelength multiplexed optical signal from the intra-node optical transmission line 634-x, and sends out the wavelength multiplexed optical signal to the intra-node optical transmission line 632-x.

When the wavelength multiplexed optical signal from the intra-node optical transmission line 631-x or the intra-node optical transmission line 634-x is input via the intra-node optical transmission line 632-x, the optical switch network 641 An optical signal of a predetermined wavelength on the internal optical transmission line 632-x is converted into an optical signal of a desired wavelength and output to a desired intra-node optical transmission line 635-x.

The optical add / drop circuit 610 receives the wavelength division multiplexed optical signals from the intra-node optical transmission line 635-x and inserts them into the wavelength division multiplexed output optical transmission line 620-x.

The optical switch network shown in FIG. 2 can be applied to the optical add / drop circuits 610 and 611 in FIG. 8, similarly to the optical add / drop circuit 110 in FIG.

The optical switch network 64 shown in FIG.
0 and 641 include the optical switch networks 140 and 14 of FIG.
As in 1, the optical switch network shown in FIGS. 4 and 5 can be applied.

The wavelength multiplex reception interface 650 and the wavelength multiplex transmission interface 651 shown in FIG. 8 are shown in FIGS. 4 and 5 similarly to the wavelength multiplex reception interface 150 and the wavelength multiplex transmission interface 151 of FIG. Configuration can be applied.

The receiving interface 6 shown in FIG.
The configuration shown in FIGS. 6 and 7 can be applied to the transmission interface 52 and the transmission interface 653, similarly to the reception interface 152 and the transmission interface 153 in FIG.

As described above, the optical communication network node according to the second embodiment of the present invention shown in FIG. 8 is the optical communication network node according to the first embodiment of the present invention shown in FIG. The same operation as the communication network node can be performed. That is, the optical communication network node in FIG. 8 drops a cell multiplexed with an optical signal of an arbitrary wavelength transmitted on an arbitrary wavelength multiplexed input optical transmission line 600-x to an arbitrary output optical transmission line 690-y. be able to.

The optical communication network node shown in FIG. 8 converts a cell from an arbitrary input optical transmission line 680-y into an optical signal of an arbitrary wavelength to output an arbitrary wavelength multiplexed output optical transmission line 620. -Can be inserted into x.

The optical communication network node shown in FIG. 8 converts the wavelength multiplexed optical signals transmitted through the wavelength multiplexed input optical transmission line 600-x into the wavelength multiplexed output optical transmission line 620-x.
Can be passed through.

Further, the optical communication network node having the configuration of FIG. 8 converts a cell multiplexed with an optical signal of an arbitrary wavelength transmitted through an arbitrary wavelength multiplexed input optical transmission line 600-x into an optical signal of an arbitrary wavelength. Then, by inserting it into an arbitrary wavelength multiplexed output optical transmission line 620-x, the wavelength multiplexed input optical transmission line 600-x and the wavelength multiplexed output optical transmission line 620-x are inserted.
It is also possible to pass signals between x.

Here, the second embodiment of the present invention shown in FIG.
The required scales of the optical communication network node according to the embodiment and the conventional optical communication network node will be compared. However, it is assumed that all traffic transmitted through the wavelength multiplexing input transmission line 600-x and the wavelength multiplexing output optical transmission line 620-x can be dropped or inserted.

The optical communication network node shown in FIG. 8 analyzes the optical add / drop circuits 610 and 611 and the optical switch networks 640 and 641 using a space division equivalent circuit.
2 (M · n) ² + 2M · n cross points are required. On the other hand, in the conventional optical communication network node, the optical switch network 1130 needs (2M · n) ² cross points.

In the conventional optical communication network node, the ATM switch requires (M · n + L) ² cross points. On the other hand, in the configuration shown in FIG. 8, the passage of the signal by the ATM switch is deleted by the introduction of the optical add / drop circuit 611, so that (2 (((M
・ N) ・ L) + L ² )

Therefore, the optical communication network node shown in FIG. 8 can be made smaller than the conventional optical communication network node.

FIG. 9 shows an optical communication network node according to the third embodiment of the present invention.

The optical communication network node shown in the figure includes a wavelength multiplexed input optical transmission line 700-x, an input optical transmission line 780-y, and a wavelength multiplexed output optical transmission line 720-x.
And an output optical transmission line 790-y and an optical signal of a desired wavelength in the wavelength multiplexed optical signal input from the wavelength multiplexed input optical transmission line 700-x. The signal is output to one of the optical transmission lines 730-x, and an optical signal having a desired wavelength among a plurality of wavelength-multiplexed optical signals incident from the intra-node optical transmission line 770-x is output to the wavelength-multiplexed output optical transmission line 720-x. And a wavelength division multiplexed optical signal incident from the intra-node optical transmission line 730-x into a plurality of optical signals having different wavelengths, and the optical signal is transmitted as it is to the optical switch network 760. A buffered wave that emits or converts an optical signal into an electrical signal, stores the ATM cells in a temporary buffer, processes the header of the ATM cell output from the buffer, converts the header into an optical signal, and emits it to the optical switch network 760. Multiple receive interface 740-x
After converting the optical signal incident from the input optical transmission line 780-y into an electric signal, the ATM cell is temporarily stored in a buffer, the header of the ATM cell output from the buffer is processed, and the optical switch is converted into an optical signal. A predetermined optical line is set between the buffered reception interface 742-y and the buffered wavelength division multiplexing reception interface 740-x and the wavelength division multiplexing transmission interface 741-x, which are output to the circuit network 760, or the buffered wavelength is set. Multiplex receiving interface 740-x and buffered receiving interface 7
An optical switch network 760 for exchanging optical signals for each cell under the control of 51-y, and an optical signal on an optical line input from the optical switch network 760 is converted into an optical signal of a predetermined wavelength as it is. Or convert the optical signal back to an electrical signal
After the cell is processed and converted to a predetermined wavelength, a plurality of optical signals converted to the predetermined wavelength are multiplexed and a wavelength-division multiplexed optical signal is output to the intra-node optical transmission line 770-x. And a transmission interface 790-y for converting an optical signal input from the optical switch network 760 into an electrical signal, converting the optical signal into an optical signal, and outputting the optical signal from the output optical transmission line 743-y. It is configured.

The optical add / drop circuit 710 receives a wavelength-division multiplexed optical signal from the wavelength-division-multiplexed input optical transmission line 700-x and, when passing the signals, passes the wavelength-division-multiplexed output optical transmission line 720-x.
Send to x. The optical add / drop circuit 710 receives the wavelength multiplexed optical signals from the wavelength multiplexed input optical transmission line 700-x and drops them to the intra-node optical transmission line 730-x.

The wavelength-division multiplexed optical signals output from the optical add / drop circuit 710 are respectively transmitted through the intra-node optical transmission lines 730-x to the wavelength-division multiplexed reception interface with buffer 740-x.
Sent to

Wavelength multiplex reception interface with buffer 7
Each of the 40-x has an input port 750- (xn-n +
1) An optical switch network 7 with n units of 750-x · n
60. Each of the buffered wavelength division multiplexing receiving interfaces 740-x demultiplexes the input wavelength division multiplexed optical signal into n wavelength optical signals, and then takes out ATM cells from the transmission frame for each of the N optical signals, Input port 750- (xn-n + 1) to 750 via buffer
-Send optical cells from xN to optical switch network 760. Alternatively, a wavelength-division multiplex receiving interface with buffer 7
After demultiplexing the input wavelength-division multiplexed optical signal into N wavelength optical signals, each of the 40-x input ports 750- (x · n−n + 1) with these n optical signals as light. ~ 75
0-x · n to the optical switch network 760.

On the other hand, each of the receiving interfaces 742-y takes out an ATM cell from the transmission frame after receiving the optical signal from the input optical transmission line 780-y, and outputs the ATM cell from the input port 750-y via the buffer. Net 76
Send an optical cell to 0.

When an optical cell is input via a buffer in the wavelength-division multiplex reception interface with buffer 740-x, the optical switch network 760 responds to the switching control signal notified from the wavelength-division multiplex reception interface with buffer 740-x. To output ports 752-1 to 752-M · n and 753-y.

When an optical signal is input without passing through a buffer in the buffered wavelength division multiplexing reception interface 740-x, the optical switch network 760 outputs predetermined output ports 752-1 to 752-. The optical signal is switched to M · n in a circuit switching manner.

Further, when an optical cell is input from the receiving interface with buffer 742-y, the optical switch network 760 receives
-Y predetermined output ports 752-1 to 752 according to the header of the cell notified by a control line (not shown).
Switch every 2-M · n and 753-y cells.

Each of the wavelength division multiplexing transmission interfaces 741-x also has an output port 752- (xn-n + 1)
Optical switch network 760 with n units of ７５752-x · n
Is connected to WDM transmission interface 741
-X is an output port 752- (xn-n + 1)
When optical cells switched for each cell are input from the optical switch network via ７５752-x · n, they are inserted into the transmission frame every n units, converted into optical signals of n wavelengths, and then converted. The wavelength-division multiplexed optical signal generated by the wave transmission is transmitted to the intra-node optical transmission line 770-x.

The wavelength division multiplexing transmission interface 741
-X is an output port 752- (xn-n + 1)
When an optical signal switched in a circuit-switching manner is inputted from an optical switch network via a signal of .about.752-x.n, the optical signal is converted into an optical signal of n wavelengths and then multiplexed to generate a wavelength multiplex. The optical signal is transmitted to the intra-node optical transmission line 770-x.

The optical add / drop circuit 710 receives the wavelength multiplexed optical signals from the intra-node optical transmission line 770-x and inserts them into the wavelength multiplexed output optical transmission line 720-x.

On the other hand, when each of the transmission interfaces 743-y receives an optical cell switched for each cell from the optical switch network via the output port 753-y, the transmission interface 743-y inserts the cell into the transmission frame and converts it into an optical signal. Output to the output optical transmission line 790-y.

The optical add / drop circuit 710 in FIG.
The optical switch network having the configuration shown in FIG. The detailed configuration of the optical switch network 760 in FIG. 9 is shown in FIG.

In the optical switch network 760, the input ports 750-x and 751-y shown in FIG. 9 have input terminals 810-1 to 810-N · n (where N · n = M · n).
+ L, the same applies hereinafter).

The wavelength converter 820- (sn-n + 1)-
820-s · n (where s = 1 to N, the same applies hereinafter) are input terminals 810- (s · n−n + 1) to 810-s, respectively.
Convert the optical signal from n into an optical signal of wavelength λz and send it to star coupler 830-s. Here, the wavelength λz may be the same as or different from the wavelength λz on the wavelength division multiplexing transmission lines 700 and 720 in FIG.

Each of the star couplers 830-s multiplexes the optical signals from the input terminals 810-(s · n−n + 1) to 810 −s · n, and then multiplexes the wavelength multiplexed signals into the optical switches 840-1 to 840. -Branch to N · n.

Optical switches 840-1 to 840-N · n
Selects one of the N wavelength multiplexed signals from the star coupler 830-s and selects the tunable wavelength filters 850-1 to 850-
N · n.

Variable wavelength filters 850-1 to 840-N
N selects an optical signal of a desired wavelength from the input wavelength-division multiplexed signal and sends it to the output terminals 850-1 to 850-Nn.

The optical switches 840-1 to 840 in FIG.
N · n and variable wavelength filters 850-1 to 850-N ·
In the case where the optical signal input from the input terminals 810-1 to 810-N · n is switched for each cell, n depends on the cell header processed by the wavelength-division multiplexing interface with buffer 740-x in FIG. The optical signal is switched for each cell by the switching control signal.

Alternatively, the optical switches 840-1 to 840-
N · n and variable wavelength filters 850-1 to 850-N ·
n is an input terminal 810-1 to 810-N · n when optical signals input from the input terminals 810-1 to 810-N · n do not need to be switched for each cell and are switched in a circuit-switching manner.
n and output terminals 860-1 to 860-N · n are controlled to set a predetermined line. Such a line is semi-fixedly set by, for example, a network management system, or is set on demand using a connection control protocol started between nodes.

As described above, the optical switch network 760 shown in FIG.
Optical signals input from 0-1 to 810-M · n can be cell-switched or line-switched to arbitrary output terminals 860-1 to 860-N · n. The details of the optical switch network shown in FIG. 10 are described in the document “Study of wavelength division / space division combined optical network” (Nishio, Suzuki, IEICE Exchange Study Group, SSE92-148, pp. 139-143).
31-36, 1992. ).

The detailed configurations of the buffered wavelength multiplexing reception interface 740 and the wavelength multiplexing transmission interface 741 in FIG. 9 are shown in FIG. 11 and FIG.

First, as shown in FIG. 11, the buffered wavelength division multiplexing reception interface 740 is connected to the intra-node optical transmission line 730-x and the input terminal 910 in FIG. Input port 750- (x
· N-n + 1) to 750-x · n are output terminals 91
1-z.

The wavelength division multiplexer 920 has an input terminal 910
From the wavelength division multiplexed signal into optical signals of n wavelengths,
Each is sent to an optical switch 930-z.

When the input optical signal is exchanged with the buffer 960-z and the optical switch network 760 by the ATM, the optical switch 930-z converts the optical signal into the photoelectric converter 94.
Switch to 0-z. Alternatively, the optical switch 930-z
When the input optical signal is switched by the optical switch network 760, the photoelectric conversion signal 940-z, the cell extraction circuit 950-z, the buffer 960-z, the routing table 970-z, and the electro-optical converter 980- Switch to optical combiner 990-z to make z a shortcut.

The opto-electric converter 940-z temporarily converts the optical signal of each predetermined wavelength from the wavelength division multiplexer 920 into an electric signal, and outputs the electric signal to the cell extracting circuit 950-z.

Each of the cell extracting circuits 950-z receives an electric signal from the photoelectric converter 940-z, extracts cells from the transmission frame, and sends the cells to the buffer 960-z. The buffer 960-z temporarily stores the input cells and sends the cells to the routing table 970-z, for example, on a first-in / first-out basis.

The routing table 970-z analyzes the header of the cell from the buffer 960-z, and outputs the output ports 752-1 to 752-1 of the optical switch 760 to be output.
752-M · n or 753-y is determined, the header is rewritten to a predetermined value, and sent to the electro-optical converter 980-z.

Further, the routing table 970-z
Is the optical switch 840-1 in the optical switch network 760.
840-M · n and tunable wavelength filters 850-1 to 85
The output port of the optical cell is notified to the optical switch network 760 for switching control of 0-N · n. Electro-optical converter 9
Each of the 80-z converts the cells from the routing table 970-z into optical cells and sends them to the optical combiner 990-z.

The optical combiner 990-z is connected to the optical switch 920
The optical signal from -z or the optical signal from the electro-optical converter 980-z is sent to the output terminal 911-z.

In this way, the wavelength-division-multiplexed reception interface with buffer 740 outputs the n optical signals multiplexed to the wavelength-division multiplexed signal from the input terminal 910 to the output terminal 911-z as optical signals without passing through the buffer. Or after each conversion into an electric signal, the cell is taken out from the transmission frame, temporarily stored in a buffer, and then output terminal 911-z
Can be output.

On the other hand, as shown in FIG. 12, the wavelength multiplexing transmission interface 741 is connected to the output ports 752- (xn-n + 1) to 752- (xn-n + 1) of the optical switch network 760 in FIG.
752-x · n are connected to the input terminal 912-z, and the intra-node optical transmission line 770-x and the output terminal 913 are connected.

The optical switch 921-z converts the optical signal into an optical-electrical converter when the input optical signal is exchanged with the buffer 960-z of the buffered wavelength division multiplexing reception interface 740 and the optical switch network 760. Switch to 931-z.

Alternatively, when the input optical signal is to be switched by the optical switch network 760, the optical switch 921-z outputs the wavelength signal 971-z (z =
1) to 8).

The photoelectric converter 931-z converts an input optical cell into an electric signal and sends it to a cell insertion circuit 941-z.

Each of the cell insertion circuits 941-z receives cells from the photoelectric converter 931-z, inserts them into the transmission frame, and sends them to the photoelectric converter 951-z.

The electro-optical converter 951-z is connected to the cell insertion circuit 9
The electric signal from 41-z is converted to a predetermined wavelength λ1
Λn, and output to the wavelength multiplexer 981 via the optical combiner 961-z.

Each of the wavelength converters 971-z converts the optical signal from the optical switch into an optical signal having a predetermined wavelength λz, and outputs the optical signal to the wavelength multiplexer 981 via the optical multiplexer 961-z.

The wavelength multiplexing device 981 includes an electro-optical converter 95.
Optical signal of n wavelengths from 1-z or wavelength converter 9
The optical signals from 71-z are multiplexed and a wavelength multiplexed signal is sent to an output terminal 913.

As described above, the wavelength multiplexing transmission interface 741 converts the optical signal from the input terminal 912-z into an electric signal, and then inserts the cells into the transmission frames to convert the cell into an optical signal of predetermined n wavelengths. Alternatively, the optical signal from the input terminal 912-z is converted into an optical signal having a predetermined number of n wavelengths as light, and the wavelength multiplexed signal is output to the output terminal 913.

The detailed configurations of the receiving interface with buffer 742 and the transmitting interface 743 shown in FIG. 9 are shown in FIGS.

First, as shown in FIG. 13, the input optical transmission line 780-y and the input terminal 1010 of FIG. 9 are connected to the buffered reception interface 742-y.
Each of the input ports 751-y of the optical switch network 760 is connected to the output terminal 1090.

The photoelectric converter 1020 is connected to the input terminal 101
In order to exchange the optical signal from 0 with the buffer 1040 and the optical switch network 760 by ATM, the optical signal is once converted into an electric signal and output to the cell extracting circuit 1030. The cell extraction circuit 1030 includes a photoelectric converter 1020
, The cell is extracted from the transmission frame, and the cell is transmitted to the buffer 1040.

The buffer 1040 temporarily stores input cells and sends the cells to the routing table 1050, for example, on a first-in / first-out basis.

The routing table 1050 analyzes the header of a cell from the buffer 1040, and outputs the output ports 752-1 to 752-1 of the optical switch 760 to be output.
2-M · n or 753-y is determined, the header is rewritten to a predetermined value, and sent to the electro-optical converter 1060.

Further, the routing table 1050 includes:
Optical switches 840-1 to 840-8 in optical switch network 760
40-N · n and variable wavelength filters 850-1 to 850-
The output port of the optical cell is notified to the optical switch network 760 for N · n switching control.

The electro-optical converter 1060 converts the cell from the routing table 1050 into an optical cell and sends it to the output terminal 1070.

In this way, the buffered reception interface 742-y converts the optical signal from the input terminal 1010 into a buffer, converts the optical signal into an electrical signal, extracts cells from the transmission frame, stores the cells in the buffer, and outputs the cells. The signal can be output to the terminal 1070.

On the other hand, as shown in FIG. 14, in the transmission interface 743-y, each output port 753-y of the optical switch network 760 shown in FIG. 9 is connected to the input terminal 1011. The output optical transmission line 790-y and the output terminal 1061 are connected. Photoelectric converter 10
21 converts the optical signal from the input terminal 1011 into an electric signal and sends it to the cell insertion circuit 1031.

The cell insertion circuit 1031 includes the photoelectric converter 1
021, input them into the transmission frame, and send them to the electro-optical converter 1041.

The electro-optical converter 1041 is connected to the cell insertion circuit 10
The electric signal from the terminal 31 is converted into an optical signal, and the output terminal 10
51.

Thus, transmission interface 743
“-Y” converts the optical signal from the input terminal 1011 into an electric signal, inserts each cell into a transmission frame, and outputs the optical signal to the output terminal 1051.

As described above, in the optical communication network node according to the third embodiment of the present invention shown in FIG. 9, the optical communication network node according to the first embodiment of the present invention in FIG. The same operation can be performed.

Here, the third embodiment of the present invention shown in FIG.
The required scales of the optical communication network node of the embodiment and the conventional optical communication network node will be compared. However,
It is assumed that all traffic transmitted through the wavelength multiplex input transmission line 700-x and the wavelength multiplex output optical transmission line 720-x can be dropped or inserted.

In the optical communication network node of FIG. 9, when the optical add / drop circuit 710 is analyzed by a space division equivalent circuit, the optical switch network 760 and the optical add / drop circuit 710 are combined ((M · n + L) ² + ( M · n)) crosspoints are required. As for the ATM switch, the optical switch network 760 is shared and (M · n +
L) The number of cross points is ² .

However, in the configuration shown in FIG. 9, the optical switch network 760 shown in FIG.
The operation of the switch network for self-routing inside the TM switch is performed simultaneously. For this reason, the number of cross points required for the optical switch network and the ATM switch is ((M · n + L) ² + (M · n)). Therefore, it is the conventional number of cross points ((2 · M
(N) ² + (M · n + L) ² ) can be significantly reduced.

Therefore, according to the optical communication network node shown in FIG. 9, the required ATM switch can be downsized while guaranteeing the same capacity as the conventional one.

The present invention can take the following aspects in connection with the description of the claims.

(1) The optical communication network node according to any one of claims 1 to 4, wherein the external input signal is input from a network or a device connected to the own node.

(2) The ATM switch outputs an input to the input terminal to a desired one of the plurality of output terminals according to the contents of an ATM cell header. Optical communication network node.

(3) The first and second ATM switches output an input to the input terminal to a desired one of the plurality of output terminals according to the contents of an ATM cell header. The optical communication network node according to claim 3, wherein

(4) The optical switch means outputs an input to the input terminal to a desired one of the plurality of output terminals according to the contents of a header of an ATM cell. An optical communication network node as described.

(5) The optical communication network node according to (4), further comprising a buffer provided before the input terminal of said optical switch means.

[0181]

As described above, in the optical communication network node according to the first embodiment of the present invention, wavelength conversion between the wavelength multiplexing input optical transmission line and the wavelength multiplexing output optical transmission line is performed by arbitrary conversion. When the optical signal of the optical switch circuit is passed, the optical switch circuit converts the optical signal from the optical switch network into an electric signal, switches the signal using an ATM switch, and converts the wavelength again using the optical switch network. This has the effect of reducing the number of crosspoints required for the network and reducing the size and cost of the nodes.

In the optical communication network node according to the second embodiment of the present invention, wavelength conversion is performed between a wavelength multiplexed input optical transmission line and a wavelength multiplexed output optical transmission line to pass an arbitrary optical signal. In this case, since the operation is performed only by the optical switch network and the optical add / drop circuit without the intermediary of the ATM switch, the number of cross points required for the optical switch network and the ATM switch can be reduced, and the node can be reduced in size and cost can be reduced. There is an effect that can be achieved.

Furthermore, in the optical communication network node according to the third embodiment of the present invention, one optical switch network is used for both the circuit switching and the self-routing switch of the ATM switch. light-
The circuit switching function of the switch network and the cell switching function of the ATM switch are performed in an integrated manner, and the size and cost of the node can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an optical communication network node according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing an example of an internal configuration of an optical add / drop circuit in FIG. 1;

FIG. 3 is a block diagram illustrating an example of an internal configuration of the optical switch circuit in FIG. 1;

FIG. 4 is a block diagram showing an example of an internal configuration of a wavelength division multiplexing reception interface in FIG. 1;

FIG. 5 is a block diagram showing an example of an internal configuration of a wavelength multiplex transmission interface in FIG. 1;

FIG. 6 is a block diagram illustrating an example of an internal configuration of a reception interface in FIG. 1;

FIG. 7 is a block diagram showing an example of an internal configuration of a transmission interface in FIG. 1;

FIG. 8 is a block diagram illustrating a configuration of an optical communication network node according to a second embodiment of the present invention.

FIG. 9 is a block diagram illustrating a configuration of an optical communication network node according to a third embodiment of the present invention.

FIG. 10 is a block diagram showing an example of an internal configuration of the optical switch circuit in FIG. 7;

11 is a block diagram showing an example of the internal configuration of a wavelength-division multiplex reception interface with a buffer in FIG. 9;

12 is a block diagram showing an example of an internal configuration of a wavelength multiplex transmission interface in FIG.

13 is a block diagram showing an example of the internal configuration of a receiving interface with buffer in FIG. 9;

FIG. 14 is a block diagram showing an example of an internal configuration of a transmission interface in FIG. 9;

FIG. 15 is a block diagram showing a configuration of a conventional optical communication network node.

[Explanation of symbols]

100-1 to 100-M Wavelength multiplexing input optical transmission line 110, 610, 611, 710 Optical add / drop circuit 120-1 to 120-M Wavelength multiplexing output optical transmission line 130-1 to 130-M Optical transmission line in node 140 , 141, 640, 641, 760 Optical switch network 150-1 to 150-M Wavelength multiplexing reception interface 151-1 to 151-M, 740-1 to 740-M Wavelength multiplexing transmission interface 152-1 to 152-L Reception Interfaces 153-1 to 153-L, 743-1 to 743-L Transmission interfaces 170, 670, 671, 672 ATM switches 740-1 to 740-M Buffered wavelength division multiplexing reception interfaces 742-1 to 742-M Buffered reception interface

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H04L 12/28 H04J 14/00 H04J 14/02 H04L 12/42

Claims (4)

(57) [Claims] 1. A first optical branching means for branching an optical signal of an arbitrary wavelength among wavelength-multiplexed wavelength-division multiplexed optical signals, and an arbitrary signal out of signals branched by the first optical branching means .
Second optical branching means for further branching an optical signal having a wavelength,
An input to which the signal branched by the second optical branching means is input.
A terminal and a plurality of output terminals.
First A for outputting to a desired one of a plurality of output terminals
Inputs a TM switch and an external input signal
The input terminal having an input terminal as a force and a plurality of output terminals;
Output to the desired one of the output terminals
A second ATM switch for performing the operation and the second ATM switch for performing the operation.
To the signal after branching by the first optical branching means.
The first optical branching means, comprising:
Means for switching the signal after branching and the external input signal.
An optical communication network node , comprising: switching means for performing switching, and first optical insertion means for joining a signal after switching by the switching means to the wavelength multiplexed signal. A plurality of first wavelength-multiplexed optical signals;
, An input optical transmission line, a plurality of second input optical transmission lines, and a plurality of first output optical transmission lines from which wavelength-multiplexed optical signals are output.
A plurality of second output optical transmission lines; a plurality of first input terminals; a plurality of second input terminals;
And a plurality of second output terminals, and the first input terminal
A desired one of a plurality of wavelength-multiplexed optical signals
A plurality of first output terminals and a second output
Output to one of the terminals and input from the second input terminal
Signal of a desired wavelength among a plurality of WDM optical signals
Optical add / drop circuit that outputs a signal to the plurality of first output terminals
And a plurality of inputs and a plurality of outputs, wherein the plurality of inputs
An optical signal of a desired wavelength is output between an end and an output end.
A first optical switch network for converting the optical signal into an optical signal; a plurality of input terminals and an output terminal;
ATM cell input from any input terminal
Output to a predetermined output terminal of the plurality of output terminals accordingly.
An ATM switch having one input terminal and a plurality of output terminals;
A wavelength-division multiplexed optical signal input from the
Demultiplex into optical signals and convert these multiple optical signals into electrical signals
ATM cells taken out of the transmission frame after
A plurality of wavelength-division multiplexed reception signals output from each of a plurality of output terminals.
Interface, one input terminal and one output terminal, and
After converting the incident optical signal to an electrical signal,
Output from the output terminal an ATM cell taken out of the system
A plurality of receiving interfaces, a plurality of inputs and an output, wherein the plurality of inputs
ATM cells input from the end are stored in the transmission frame,
After being converted to optical signals with different wavelengths, they are combined and generated
A plurality of wavelength multiplexed optical signals emitted from the output end.
A wavelength multiplexing transmission interface, one input terminal and one output terminal, and
The input ATM cell is stored in the transmission frame and the optical signal
After being converted to a plurality of transmission in
Is configured to include a interface, wherein the plurality of first input optical transmission path of the optical add drop circuit
Connected to a first input terminal, and each of the second output terminals of the optical add / drop circuit is connected to the first input terminal .
Each of the plurality of inputs of the optical switch network is connected to a plurality of inputs of the first optical switch network.
Connected to the input terminal of each of the multiple WDM reception interfaces.
It is continued, each of the plurality of reception of the plurality of second input optical transmission line
Connected to the input end of the interface, and each of the plurality of output ends of the wavelength multiplex reception interface.
The output terminal of the receiving interface is connected to the ATM switch.
And the output terminal of the ATM switch is connected to the wavelength multiplexing transmission interface.
Each of a plurality of input terminals of the interface and the transmission interface
It is connected to the input end, a plurality of wavelength division multiplexing transmission interface each output end
Each of the plurality of input terminals of the second optical switch network is connected.
Are continued, a plurality of output ends of said second optical switching network is the optical branching
A first input terminal of the optical add / drop circuit connected to each of the second input terminals of the branch insertion circuit;
An output end of the plurality of transmission interfaces connected to an output optical transmission line .
2 is connected to each of the two output optical transmission lines.
Optical communication network node. 3. A plurality of first wavelength-multiplexed optical signals to be inputted.
, An input optical transmission line, a plurality of second input optical transmission lines, and a plurality of first output optical transmission lines from which wavelength-multiplexed optical signals are output.
A plurality of second output optical transmission lines; a plurality of first input terminals; a plurality of second input terminals;
And a plurality of second output terminals, and the first input terminal
A desired one of a plurality of wavelength-multiplexed optical signals
A plurality of first output terminals and a second output
Output to one of the terminals and input from the second input terminal
Signal of a desired wavelength among a plurality of WDM optical signals
And second light that outputs the light to the plurality of first output terminals.
A drop-and-insert circuit, having a plurality of input terminals and a plurality of output terminals;
An optical signal of a desired wavelength is transmitted between an end and an output end.
A first and a second optical switch network for converting into a signal, a plurality of input terminals and a plurality of output terminals,
The ATM cell input from the end is output according to the header.
First to third ATMs which output to predetermined output terminals of the terminals
A switch, one input terminal and a plurality of output terminals, wherein the one input terminal
A wavelength-division multiplexed optical signal input from the
Demultiplex into optical signals and convert these multiple optical signals into electrical signals
ATM cells taken out of the transmission frame after
A plurality of wavelength-division multiplexed reception signals output from each of a plurality of output terminals.
Interface, one input terminal and one output terminal, and
After converting the incident optical signal to an electrical signal,
Output from the output terminal an ATM cell taken out of the system
A plurality of receiving interfaces, a plurality of inputs and an output, wherein the plurality of inputs
ATM cells input from the end are stored in the transmission frame
Later, they are converted into optical signals with different wavelengths, combined and generated
A plurality of wavelength multiplexed optical signals emitted from the output end.
A wavelength multiplexing transmission interface, one input terminal and one output terminal, and
After storing the input ATM cell in the transmission frame,
A plurality of transmission interfaces that convert the signals into signals and output from the output end.
Is configured to include a face, wherein the plurality of first input optical transmission path the first optical add drop
A second input terminal of the first optical add / drop circuit connected to a first input terminal of the circuit;
A plurality of inputs of the first optical switch network, each of the plurality of outputs of the first optical switch network being
The second optical add / drop circuit is connected to a first input terminal of the second optical drop / add circuit, and each of the second output terminals of the second optical drop / add circuit is
Connected to each input terminal of multiple wavelength multiplex receiving interfaces
Is, each of the plurality of reception of the plurality of second input optical transmission line
Each of the plurality of output terminals of the wavelength multiplex reception interface is connected to an input terminal of the interface.
An output terminal of the receiving interface is connected to an input terminal of the first ATM switch, and an output terminal of the receiving interface is connected to the second ATM switch .
And the input terminal of the third ATM switch.
Connected to the output terminal of the second ATM switch and the first ATM switch.
The output terminal of the switch is the input terminal of the transmission interface.
And the output terminal of the third ATM switch is connected to the wavelength multiplex transmission.
An output end of each of the plurality of wavelength multiplex transmission interfaces is connected to each of a plurality of input ends of the interface;
Connected to each of the second input terminals of the second optical add / drop circuit
And a first output terminal of the second optical add / drop circuit is the second output terminal.
Is connected to each of the multiple input ends of the optical switch circuit network, a plurality of output ends of said second optical switching network is the first
Are connected to each of the second input terminals of the optical add / drop circuit, and the first output terminal of the first optical add / drop circuit is
Connected to a first output optical transmission line, wherein output ends of the plurality of transmission interfaces are connected to the plurality of
2 is connected to each of the two output optical transmission lines.
Optical communication network node. 4. A plurality of first signals to which a wavelength multiplexed optical signal is inputted.
, An input optical transmission line, a plurality of second input optical transmission lines, and a plurality of first output optical transmission lines from which wavelength-multiplexed optical signals are output.
A plurality of second output optical transmission lines; a plurality of first input terminals; a plurality of second input terminals;
And a plurality of second output terminals, and the first input terminal
A desired one of a plurality of wavelength-multiplexed optical signals
A plurality of first output terminals and a second output
Output to one of the terminals and input from the second input terminal
Signal of a desired wavelength among a plurality of WDM optical signals
Optical add / drop circuit that outputs a signal to the plurality of first output terminals
And one input terminal and a plurality of output terminals, wherein the one input terminal
A wavelength-division multiplexed optical signal input from the
After demultiplexing into optical signals, these multiple optical signals
Emitting light from each of the plurality of output terminals, or
Optical signal is converted to an electrical signal and extracted from the transmission frame.
ATM cells are temporarily stored in a buffer, and
After processing the header of the output ATM cell,
A plurality of waves converted and emitted from each of the plurality of output ends
A long multiplex reception interface, one input terminal and one output terminal, and
Converts the incoming optical signal into an electrical signal and converts it into a transmission frame.
Optical signal after processing the header of the ATM cell taken out
And a plurality of reception interfaces for converting the
And a plurality of inputs , the plurality of inputs and one output being provided.
The optical signal on the optical line input from the end
Or convert the optical signal to an electrical signal.
Converted and extracted ATM cells are stored in the transmission frame
Later, either one of the above-mentioned conversion to the predetermined wavelength is performed.
After the, if an optical signal of multiple converted to the predetermined wavelength
A plurality of wavelength-multiplexed optical signals,
A wavelength multiplexing transmission interface, one input terminal and one output terminal, and
AT that is converted by converting an input optical signal into an electrical signal
After storing the M cells in the transmission frame,
A plurality of transmission interfaces for emitting from the output end, a plurality of input ends and a plurality of output ends, wherein the plurality of predetermined interfaces are provided;
The predetermined optical line is connected between the input terminal and the output terminal of
Setting or the plurality of wavelength multiplex reception interfaces.
And optical signals are exchanged for each cell under the control of the receiving interface.
An optical switch network , wherein the plurality of first input optical transmission lines are connected to the optical add / drop circuit.
Connected to a first input terminal, wherein each of the second output terminals of the optical add / drop circuit is connected to the plurality of
Each of the plurality of second input optical transmission lines is connected to an input terminal of each of the wavelength division multiplexing reception interfaces, and
Connected to the input end of the interface, and each of the plurality of output ends of the wavelength multiplex reception interface.
The output end of the receiving interface is connected to the optical switch circuit.
And an output end of the optical switch network is connected to the input end of the optical network.
A plurality of input terminals of the interface and the transmission interface.
Is connected to the input end of the scan, the plurality of wavelength division multiplexing transmission interface each output end
The optical add / drop circuit is connected to each of the second input terminals, and the first output terminal of the optical drop / add circuit is connected to the plurality of first
An output end of the plurality of transmission interfaces connected to an output optical transmission line .
2 is connected to each of the two output optical transmission lines.
Optical communication network node.