JPH10200475A - Output recontention space/wavelength mixed light switching system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To minimize the size of a space sharing light switch, maintaining a constant cell loss ratio and to facilitate capacity increase. SOLUTION: Many light switching subsystems 500 in which output terminals are parallelly connected have many input modules 3 which analyze switching state information of each different wavelength group that corresponds to an incoming address of an inputted cell, perform wavelength conversion according to wavelength information and output it, a wavelength multiple space sharing light switching module 1 which outputs by delaying by one time slot through an output terminal when routing information is added to a cell that is inputted from the module 3 and outputs to a corresponding output terminal when it is not, many wavelength group demultiplexers 4 which demultiplex a cell that is inputted from the module 1 and many output modules 5 which input cells of different wavelength groups, filter each wavelength, convert it into an electric signal and output it, and carry out output recontention over two time slots.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an output re-contention (content
ion resolution) This is related to the space / wavelength mixed type optical switching system. In particular, not only audio, data, and still images, but also high definition TV (HDTV: High Definition)
Television) Large-capacity ATM (Asynchrono) that can use large-capacity subscriber video services such as distribution services
us Transfer Mode) The present invention relates to an output re-conflict space / wavelength mixing type optical switching system for obtaining a transmission rate of several Tb / s class or more in an exchange.

[0002]

2. Description of the Related Art Generally, in realizing an N.times.N self-routing optical switch, a conventional wavelength division type spatial switch employs an output re-conflict execution process over two time slots by applying about 50% to a single output terminal. Although the effect of reducing the number of optical elements can be obtained, when realizing a large-capacity optical switch (that is, when N is large), the dimension of the star coupler is very (N + N / 2) × (4N + N / 2). Larger, about N / 2 single frequency laser diodes and frequency tunable filters must be added.

[0003]

Also, in the case of a mixed space / wavelength type optical switch, since a large number of cells are multiplexed at different wavelengths on the internal link on the space switch, the size of the space switch is N × N is suitable for realizing a large-capacity switch while maintaining N, but in order to guarantee a certain level of cell loss rate in output re-contention over one time slot, there is a problem that the tunable wavelength range of the tunable light source is very wide. there were.

Accordingly, the present invention for solving the various problems with respect to the prior art described above, comprises a parallel unit of a space / wavelength type optical switch of a basic unit, and an output re-contention over two time slots. To minimize the number of fixed filters required at the output end and the size of the space division optical switch while maintaining a constant cell loss rate, and increase the capacity by adding an optical switch in a basic unit. It is an object of the present invention to provide an output re-conflict space / wavelength mixed type optical switching system capable of easily performing the above operation.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, according to the present invention, the output terminals of a plurality of optical switching subsystems are connected in parallel, and each of the optical switching subsystems is connected to an input cell. Extracting the destination address, analyzing the switching state information corresponding to the destination address among the switching state information corresponding to the plurality of optical switching subsystems one-to-one, and immediately outputting the output to a desired output terminal. A large number of input cell processing means for converting the wavelength and outputting it, and adding routing information for delaying one time slot if output is not possible immediately to a desired output end, and performing wavelength conversion based on the wavelength information and outputting; Routing information for analyzing cells input from the plurality of input cell processing means and delaying them by one time slot for output; Is added, the output is delayed by one time slot and output through the output terminal, otherwise the wavelength-division multiplexed cell is output at the corresponding output terminal. A plurality of wavelength group demultiplexing means for inputting a plurality of multiplexed cells from the division optical switching means, respectively demultiplexing the cells, and outputting the demultiplexed cells to the optical switching subsystem corresponding to each wavelength group; and There are many switching subsystems including output means for inputting cells for each wavelength group from the wavelength group demultiplexing means of the optical switching subsystem, filtering each wavelength, converting them into electric signals, and outputting the electric signals. , The switching subsystems are connected in parallel.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described in detail with reference to the attached drawings.

FIG. 1 shows a large-capacity ATM to which the present invention is applied.
1 shows a schematic configuration diagram of an optical switching system.

In an ATM optical switching system as shown in the drawing, an input / output signal is an AT having a speed of v (eg, 155 Mb / s).
As M cells, each cell is 53 bytes long.
The cell multiplexing unit 200 as an electronic circuit has a speed V (eg, 2.
It is connected to the optical switching system 100 via a 5 Gb / s) data bus. The input cells are subjected to header processing in the header conversion unit 300 and then stored in a buffer in the cell multiplexing unit 200 to avoid cell loss caused by instantaneous call congestion.

The optical switching system 100 receives a plurality of cells in the same time slot from a plurality of cell multiplexing units 200, recognizes incoming addresses of each cell, and has the corresponding incoming address through a V data bus. It performs a self-routing switching function of outputting an input cell to the cell demultiplexing unit 400.

[0010] Even when a large number of input cells are simultaneously switched to the same incoming cell demultiplexing unit 400 instantaneously, the optical switching system 100 maintains the minimum cell loss rate while maintaining the overall optical switching system. The transmission rate must not be reduced.

The cell demultiplexing unit 400 as an electronic circuit includes:
After the headers of the cells input from the optical switching system 100 are reconverted by the header conversion unit 300 ', the cells are temporarily stored in a buffer to avoid cell loss, and the ATM cells are output at a speed of V (155 Mb / s).

Accordingly, the switching capacity of the ATM optical switching system depends on the structure and the switching system of the optical switching system 100, and a space / wavelength mixed type optical switch of a basic unit is configured in parallel to facilitate the increase of the capacity. By applying the output re-conflict process over two time slots to the unit switch, the number of fixed filters required at the output terminal and the size of the space division optical switch can be minimized.

FIG. 2 is a block diagram of the optical switching system 100 according to the present invention. In FIG. 2, reference numeral 1 denotes a space division optical switch module, 2 denotes a one-cell delay unit, 3 denotes an input module, 4 denotes a wavelength group demultiplexer, Denotes an output module, and 6 denotes a common buffer controller.

The optical switching system of the present invention can minimize the size of the switch and the number of wavelength filters while maintaining a low cell loss ratio, and the capacity can be easily increased because the number of optical switching subsystems is 500 units.

Optical switching system 10 as shown in the drawing
0 is configured to have a parallel structure as m optical switching subsystems 500. Each subsystem 5
00 is a wavelength division multiplexing space division optical switch module 1, 1,
It comprises a cell delay unit 2, n input modules 3, n wavelength group demultiplexers 4, n output modules 5, and a common buffer controller 6.

The input / output terminals of the space division optical switch module 1 are unidirectionally connected to n input modules 3 and a wavelength group demultiplexer 4, respectively, to n input / output optical fiber lines. The one-cell delay unit 2 is interconnected to input / output terminals of the space division optical switch module 1 and nf optical fibers.

The input terminals of the output module 5 are interconnected with the output ends of each wavelength group demultiplexer 4 located in the m optical switching subsystems 500 and the m optical fiber lines.

The common buffer controller 6 is connected to n input modules 3 and bidirectional control signal lines. The n input modules 3 are connected to each other through unidirectional control signal lines 7 in a ring. It is a configuration of the form.

Here, considering the switching operation for a large number of input cells with reference to the above configuration, if one cell arrives at each input module 3, each input module 3 Analyzes the incoming address from the header of the received cell, determines the output end of the space division optical switch module 1 through the unidirectional control signal line 7, and overlaps the wavelength with each output end of the space division optical switch module 1. The wavelength of each input cell is converted so as not to be performed.

The unidirectional control signal line 7 is composed of m parallel buses one to one corresponding to the m optical switching subsystems 500. Each parallel bus has n parallel buses corresponding to the destination address one by one. Are re-circulated from the input module 1 to the input module n one time within one time slot time of the cell to which the output re-conflict packet is input.

Each output re-contention packet stores up to L pieces of switching state information for the current incoming cell and one cell time slot before the incoming cell for one destination address.

Each input module 3 analyzes the incoming address from the header of the input cell, and if an output re-conflict packet having the corresponding incoming address is received from the previous input module, the status information of the output re-conflict packet is converted into one time slot. The search is performed in the order of the previous state information and the current state information, and the wavelength information used for the wavelength conversion is determined so as not to be duplicated. Then, after changing the state of the output re-contention packet, the output re-contention packet is transmitted to the next input module 3.

When the output re-contention process over one cycle is completed, each input module 3 replaces the current state information of the output re-contention packet with the state information before one cell time slot time, and is input at the next time. Such a process is repeated for each cell.

Therefore, the state information of each output re-conflict packet before one cell time slot has information on the number and wavelength of cells to be switched to the corresponding output terminal in the previous time slot, based on the current cell input time. Become like Since up to L switching state information before one time slot can be stored, wavelength conversion is performed by designating different wavelengths for a maximum of L input cells. In addition, since up to L pieces of current switching state information can be stored, if the value of the previous switching state information is I at any given moment, a maximum of 2 can be obtained through an output re-conflict process.
For the LI input cells, different wavelengths are selected and switched to the incoming / outgoing end, and the input cells beyond that are not wavelength-selected, so that loss processing is performed.

When the incoming address of the input cell is translated and switched to another optical switching subsystem 500, the signal is transmitted through one of the m unidirectional control signal lines 7 corresponding to the optical switching subsystem 500 one-to-one. An output re-contention process is performed in the same manner as described above. However, in order to avoid wavelength overlap, different wavelength groups are designated and selected. That is, the wavelength conversion for the input cell is performed in the wavelength groups λ ₁₁ , λ _{12 ,.} Groups λ ₂₁ , λ ₂₂ ,..., Λ _2L , wavelength groups λ _m1 , λ _m2 ,
... selected within λ _mL .

When a large number of cells input to an input terminal of an arbitrary optical switching subsystem are switched to an output terminal of an arbitrary optical switching subsystem, if the number of input cells is less than L, it is handled. Through the output re-conflict process through one of the m unidirectional control signal lines 7, up to L different wavelengths can be converted from the previous time slot state information in the corresponding wavelength group. It is switched to the incoming output as it is (no time delay).

However, in general, when the state information before one time slot time of the output re-contention packet is I and I cells are already waiting in the one-cell delay unit 2, the switching state information before the output re-contention process is used. The L-1 input cells are switched to the incoming output end (with no time delay). The remaining input cells perform wavelength conversion different from each other up to a maximum of L from the current switching state information of the output re-conflict process, and these cells become 1
After being stored in the cell delay unit 2 for one time slot time,
The input module 3 is switched from the common buffer controller 6 to the one-cell delay unit 2 so as to be switched to the corresponding output terminal.
After receiving the routing information including the address of the above and inserting it into the cell header, the space division optical switch module 1
Send to

When the common buffer controller 6 receives the use request signal of the cell delay unit including one incoming address from the input module 3, the common buffer controller 6 classifies the incoming address, and the address of the incoming optical switching subsystem 500 becomes Although different, the one-cell delay unit 2 allows the destination address in the optical switching subsystem 500 to be wavelength-multiplexed and stored in the same cell for one time slot.
Is sent to the corresponding input module 3.

The space division optical switch module 1 analyzes the routing information of the cell input from the input module 3, and if the routing information does not include the address of the one-cell delay unit 2, the space division corresponding to the arrival address. Switching to the output end of the optical switch module 1,
When the address of the one-cell delay unit 2 is included, switching is performed to the output terminal of the space division optical switch module 1 to which the one-cell delay unit 2 is connected.

The input cell received from the one-cell delay unit 2 is switched to the output terminal of the space division optical switch module 1 corresponding to the destination address in the routing information.

As described above, when the output re-conflict packet is subjected to the output re-conflict process over one time slot in which the current and previous switching state information of the output re-conflict packet is redundantly used, the input cell has two switching opportunities. Accordingly, the required cell loss ratio can be maintained while the value of L is reduced, and the number of wavelengths used for wavelength conversion can be reduced, so that the number of filters is also reduced.

The input cell wavelength-converted from the current state information of the output re-contention packet is also stored in the one-cell delay unit 2 as a wavelength multiplexed state. The number of terminals nf is also reduced, which is advantageous for realizing a large-capacity optical switch module.

The wavelength group demultiplexer 4 comprises mL cells multiplexed into m wavelength groups from the output end of the space division optical switch module 1 to the same destination output end in the m optical switching subsystems 500. And demultiplexes these wavelength signals for each wavelength group. And a wavelength group demultiplexer 4
Is demultiplexed wavelength group signals _{λ 11, λ 12, ... λ} 1L to the output module 5 of the optical switching subsystem 1, the wavelength group signal _{λ 21, λ 22, ... λ} 2L is the optical switching subsystem 2 A wavelength group signal λ _m1 , λ _m2 ,
... Λ _mL are transmitted to the output modules 5 of the optical switching subsystem m through optical fiber lines.

Each output module 5 receives at most mL cells from the output ends of the m wavelength group demultiplexers 4 in each optical switching subsystem 500 through m optical fiber lines. That is, the wavelength group signal of the cell input to the output module 5 by the wavelength group demultiplexer 4 is converted into the optical switching subsystem 50 to which the output module 5 belongs.
Therefore, all output modules 5 in one optical switching subsystem 500 receive signals of the same wavelength group through m optical fiber lines.

For example, the optical switching subsystem 500
Since the output module 5 in i has to receive mL cells multiplexed with each wavelength group i, the output module 5 is composed of L cells that can select L cells for one wavelength group i. Using m fixed filters (wavelength filters λ ₁₁ , λ ₁₂ ,..., Wavelength filters λ _1L ), a maximum of mL cells are received.

Each output module 5 is connected to the cell demultiplexer 4
Since the data bus is connected to the data bus of 00 and V, the data is stored in a buffer for a while to prevent cell loss, and then each cell is sequentially output to the cell demultiplexing unit 400.

Therefore, the optical switching system 100 of the present invention performs output re-contention over two time slots, so that the input cell has two switching opportunities, and the required value can be reduced while the value of L is reduced. Since the cell loss ratio can be maintained, the number of wavelengths used for wavelength conversion can be reduced, so that the number of filters is also reduced.

The input cell wavelength-converted from the current state information of the output re-conflict packet is also stored in the one-cell delay unit 2 in a wavelength-multiplexed state, so that one cell added to the space division optical switch module 1 The number nf of input / output terminals for delay is also sufficient if n / (L + 1), which is advantageous for realizing a large-capacity optical switching module.

FIG. 3 shows a configuration diagram of the wavelength division multiplexing space division optical switching module 1 according to the present invention.

As shown in the drawing, (n + nf) × (n + nf)
The space division optical switch module 1 is composed of n + nf optical space switches 10 and 11 and n + nf optical couplers 12 and 13, and the one-cell delay unit 2 has nf
It is composed of the optical fiber delay lines 14.

The optical space switches 10 and 11 have one input terminal and n + nf output terminals, and the optical couplers 12 and 13 have n + nf input terminals and one output terminal.

Each of the n optical space switches 10 connected to the input module 3 by an input optical fiber line has its output end interconnected to a (n + nf) optical couplers 12 and 13 one-to-one with a unidirectional optical transmission bus. However, the output ends of the nf optical space switches 11 connected to the output ends of the optical fiber delay lines 14 are interconnected one-to-one with the n optical couplers 12 by a unidirectional optical transmission bus. To be configured.

Then, in the case of the optical coupler 13 and the optical space switch 11, which are respectively connected to the input terminal and the output terminal of the optical fiber delay line 14 one by one, nf out of n + nf input / output terminals are not connected.

Each of the n optical couplers 12
Multiple wavelength group demultiplexers 4 using one output optical fiber line
Are connected one to one.

The optical space switch 10 analyzes the routing information of the input cell received from the input module 3 and, if the address of the one-cell delay unit 2 is not included, connects to the input end of the optical coupler 12 corresponding to the destination address. If the address of the one-cell delay unit 2 is included, switching is performed to the input terminal of the optical coupler 13 to which the corresponding optical fiber delay line 14 is connected.

The optical space switch 11 connected to the optical fiber delay line 14 is connected to the optical coupler 12 corresponding to the incoming address in the routing information of the input cell.
Is switched to the input terminal of.

Therefore, the optical fiber delay line 14 has:
Wavelength groups λ ₁₁ , λ ₁₂ ,... Λ _1L , wavelength groups λ ₂₁ , λ ₂₂ ,.
λ _2L , wavelength groups λ _m1 , λ _m2 ,..., λ _mL, etc., are stored for about one time slot time with wavelength multiplexing of up to mL input cells, and switched to the corresponding output terminal at the next cell time slot time Is done.

Similarly, the optical coupler 12 outputs to the wavelength group demultiplexer 4 through the output optical fiber line the input cells in which the maximum number of mL input cells are multiplexed into wavelengths different from each other.

FIG. 4 is a block diagram of the input module 3 according to the present invention. The input module 3 includes a cell buffer 30, a routing information inserter 31, and a tunable laser diode 3.
2, the output re-conflict and wavelength controller 33 is provided.

After one cell arrives at the cell buffer 30 from the cell multiplexing unit 200, the incoming address contained in the cell header is transmitted to the output re-contention and wavelength controller 33, and the input cell is transmitted to the routing information inserter. It is sent to 31.

The output re-contention and wavelength controller 33 performs the output re-contention process over the two time slots using the output re-contention packet through the m output re-contention parallel buses of the unidirectional control signal line 7 as described above. Perform That is, if the state information before one time slot time of the output re-contention packet received through the parallel bus is less than L,
One wavelength tunable information is selected from the corresponding wavelength group using the previous state information, and if it is larger than L, the current switching state information of the output re-conflict packet is examined. One piece of wavelength tunable information is selected from the current state information by an appropriate method.

If all of the previous and current state information of the output re-conflict packet is larger than L, the loss processing is performed because the wavelength cannot be specified for the input cell.

After one wavelength is selected in this manner, the output re-conflict and wavelength controller 33 increments the corresponding state information through the wavelength selection process by one and returns the output to the next input module through the parallel bus. Transmit competing packets.

Then, the output re-contention and wavelength controller 33
Assigns the address of the one-cell delay unit 2 from the common buffer controller 6 to store one cell time period in the one-cell delay unit 2 when one wavelength is selected from the state information before one time slot time. In response to this, the routing information is transmitted to the routing information inserter 31 and the tunable laser diode 32 is transmitted with the tunable information.

The routing information inserter 31 inserts the output re-conflict and the routing information input from the wavelength controller 33 into the header of the cell received from the cell buffer 30, and the tunable laser diode 32 outputs the re-conflict and wavelength. The cell received from the routing information inserter 31 is wavelength-converted by the wavelength variable information input from the controller 33 and transmitted to the space division optical switch module 1.

FIG. 5 illustrates m wavelength groups corresponding to m optical switching subsystems 500 one by one in order to avoid wavelength overlap in the input module 3 performing the wavelength conversion function. Here, the wavelength tunable laser diode 32 is designated by the output re-conflict and wavelength controller 33 to one of the mL wavelengths shown.

FIG. 6 shows a configuration diagram of the output module 5 according to the present invention. The output module 5 includes a fixed filter 50, an opto-electric (O / E) converter 51, and a buffer memory 52.

The m fixed filters 50 use the fixed filters λ ₁₁ , λ ₁₂ ,... Λ _1L for the wavelength group i, respectively.
The wavelength multiplexed cells input from the m wavelength group demultiplexers 4 are filtered into L wavelengths.

The photoelectric converter 51 converts an input cell of an optical signal wavelength-filtered from the fixed filter 50 to L optical fiber lines by using L photoelectric conversion circuits, respectively, into an electric signal.

The output module 5 receives the maximum mL cells at the same time and stores them in the buffer memory 52 for a while in order to prevent a temporary cell loss.
Each cell is output to the cell demultiplexing unit 400 at the speed of V while maintaining the order of incoming cells.

As described above, the present invention allows various substitutions, modifications, and changes within the scope of the technical idea of the present invention to those skilled in the art to which the present invention pertains. It is not limited to the form and the drawing.

[0062]

According to the present invention as described above, the m optical switching subsystems 500 are connected in a parallel structure, and each optical switching subsystem 500 has two cells per input cell.
Since the input cell has two switching opportunities by performing output re-contention over the time slot, the required cell loss rate can be maintained while reducing the value of the number L of variable wavelengths. Not only can the number of wavelengths and the number of filters used for conversion be reduced, but also the input cells whose wavelengths have been converted from the current state information of the output re-conflict packet are stored in the one-cell delay unit in a wavelength-multiplexed state. Therefore, it is sufficient if the number of input / output terminals nf added to the space division optical switch module is n / (L + 1). When the capacity is to be expanded, it is sufficient to add the optical switching subsystem for each optical switching subsystem. It is advantageous for realizing.

As a result of analyzing the performance of the optical switch proposed as a reference, when the number of optical switching subsystems is four, the load condition of input traffic density = 0.9 and 1E
Under the cell loss condition of −11, the number L of variable wavelengths used for one wavelength group needs to be L = 4, and the dimension of the optical switching subsystem is (n + n / 5) × (n + n).
/ 5).

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an ATM optical switching system to which the present invention is applied.

FIG. 2 is a configuration diagram of an output re-conflicting optical switching subsystem according to the present invention.

FIG. 3 is a configuration diagram of a space division optical switch module according to the present invention.

FIG. 4 is a configuration diagram of an input module according to the present invention.

FIG. 5 is an exemplary diagram of a wavelength variable range of the laser diode according to the present invention.

FIG. 6 is a configuration diagram of an output module according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 space division optical switch module 2 1 cell delay device 3 input module 4 wavelength group demultiplexer 5 output module 6 common buffer controller 7 unidirectional control signal line 10, 11 optical space switch 12, 13 optical coupler 30 cell buffer 31 routing Information inserter 32 wavelength tunable laser diode 33 output re-conflict and wavelength controller 50 fixed filter 51 photoelectric converter 52 electrical buffer memory 100 optical switching system 200 cell multiplexing unit 300, 300 'header conversion unit 400 cell demultiplexing unit 500 light Switching subsystem

Claims (9)

[Claims] 1. A method for extracting an incoming address of an input cell and analyzing the switching state information corresponding to the incoming address from among switching state information corresponding to a plurality of optical switching subsystems. If the output can be output to the desired output terminal, the wavelength is converted according to the wavelength information and output. If the output is not possible immediately to the desired output terminal, routing information for delaying one time slot is added, and the wavelength is calculated based on the wavelength information. A large number of input cell processing means for converting and outputting; about one time slot when routing information for analyzing cells input from the large number of input cell processing means and delaying and outputting the cells by one time slot is added; Spatial division that delays and outputs through the output end, otherwise outputs the applied wavelength-multiplexed cell to the corresponding output end A switching means; a plurality of wavelength groups for receiving a plurality of multiplexed cells from the space division optical switching means, respectively demultiplexing them, and outputting the demultiplexed cells to the corresponding optical switching subsystem for each wavelength group; Multiplexing means; and output means for inputting cells for each wavelength group from the wavelength group demultiplexing means of each of the optical switching subsystems, filtering each wavelength, converting them into electric signals, and outputting the signals. An optical switching system comprising a number of subsystems, wherein the switching subsystems are connected in parallel. 2. The optical switching system according to claim 1, further comprising means for storing routing information for delaying an input cell by one time slot and outputting the routing information in response to a request from said input cell processing means. system. 3. The optical switching subsystem according to claim 1, wherein the switching state information corresponding to each of the plurality of optical switching subsystems is one for the corresponding optical switching subsystem.
An optical switching system storing wavelength information of a current time slot of wavelength information before a time slot. 4. The input cell processing means according to claim 3, wherein the input cell processing means analyzes the wavelength information stored between previous time slots of the switching state information corresponding to the incoming address of the input cell and, if there is room, the wavelength If the wavelength information stored in the previous time slot is used and all the wavelength information stored in the previous time slot is used, the wavelength information stored in the current time slot is analyzed and there is available wavelength information. Routing information for delaying one time slot is added, the wavelength is converted using the wavelength information of the current time slot, and the converted wavelength information is output, so that the wavelength information between the current time slots is changed to the previous wavelength information. An optical switching system comprising: 5. The plurality of input cell processing units according to claim 4, wherein each of the plurality of input cell processing units is connected in a ring form through a parallel bus corresponding to the plurality of optical switching subsystems. Characteristic optical switching system. 6. The input cell processing unit according to claim 1, wherein the input cell processing unit inputs a wavelength multiplexed cell and buffers the input cell, and extracts an incoming address of the cell input from the buffering unit and performs the parallel processing. If the previous wavelength information for wavelength conversion has a margin by analyzing the switching state information corresponding to the destination address through a bus, only the wavelength variable information is output, and the previous wavelength information has no margin,
Output re-contention and wavelength control means for inputting the routing information for delaying the one time slot and outputting routing information and wavelength tunable information when the current wavelength information has a margin; input from the output re-contention and wavelength control means Means for inserting the routing information into the cell input from the buffering means if there is routing information obtained; and outputting the output of the routing information insertion means using the wavelength variable information input from the output re-conflict and wavelength control means. An optical switching system comprising: means for varying and outputting a signal. 7. The multi-wavelength group according to claim 1, wherein the space division optical switching means comprises: a plurality of input terminals for inputting cells output from the plurality of input cell processing means; And a plurality of optical fiber delay lines for delaying one time slot when a cell input to the input terminal must be output with one time slot delay. An optical switching system comprising a number of input / output terminals coupled to the optical switching system. 8. The routing information according to claim 7, wherein the space division optical switching means is connected to the plurality of input cell processing means in a one-to-one manner through an optical fiber line and inputted cells are delayed by one time slot. Is inserted into the output end coupled to the optical fiber delay line,
If the cell is not a cell into which routing information for time slot delay is inserted, a plurality of first optical switching means for outputting to the output end of the wavelength group whose wavelength has been changed; one time slot coupled to the plurality of optical fiber delay lines A plurality of second optical switching means for receiving the delayed wavelength-converted cells and outputting the cells to an output terminal of a corresponding wavelength group; a wavelength connected to the plurality of first optical switching means for delaying one time slot; A plurality of first optical coupling means for inputting the changed cell and outputting the same to the second optical switching means through the optical fiber delay line; and a wavelength tunable connected to the first and second optical switching means. An optical switch comprising a plurality of second optical coupling means for outputting a cell to said wavelength group demultiplexing means. Gushisutemu. 9. The wavelength group according to claim 8, wherein the output unit is connected to a wavelength group demultiplexing unit for one wavelength group located in the plurality of optical switching subsystems, and outputs the one wavelength group. A plurality of filtering means for receiving and filtering a plurality of wavelengths respectively; a plurality of photoelectric conversion means respectively connected to the plurality of filtering means to convert a plurality of optical signals into electric signals; and the plurality of photoelectric conversions An optical switching system comprising: means for buffering input cells connected to the means.