JPH06164610A - Circuit assigning method and wavelength multiplex communication system - Google Patents

Abstract

PURPOSE:To provide a wavelength multiplex communication system applying a line assigning method where each node can dispersedly control the wavelength or the time slot without needing a control node. CONSTITUTION:Plural large capacity lines using the wavelength multiplexing are provided together with a control circuit which controls the wavelength or the time slot of each line. A circuit control table WC which shows the wavelengths or the time slots used by those large capacity lines is circulated on the control circuit. Then the node that fetches the table WC selects the idle wavelengths or time slots to assign the circuits. Then the table WC is rewritten and circulated again in a network. In such a way, the dispersed wavelength control is performed so that the communication procedure can be simplified with no control node needed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wavelength division multiplexing optical communication system, and more particularly to a line allocation method and a network configuration.

[0002]

2. Description of the Related Art In recent years, a system in which a large amount of information such as a moving image is taken into a computer network has been studied. Proposed. In this system, a plurality of wavelengths λ _a and λ _{1 to} λ _n are used, λ _a communicates low-speed data and wavelength control information through an existing LAN, and λ _{1 to} λ _n uses speed by wavelength multiplexing transmission. To provide a communication service that does not depend on (the speeds may be mixed). These wavelengths λ _a and λ ₁ ~
The signal of λ _n is accommodated on one loop transmission line.

As the wavelength division multiplex transmission system, a wavelength division multiple access (DA-WDMA) system based on demand assignment is adopted, and this requires a high speed communication or a long holding time communication between certain nodes. At this time, a specific wavelength is assigned to the communication between the nodes, and a line channel is set up by the wavelength to perform communication.

The wavelength allocation method will be described in more detail with reference to FIGS. 17 and 18. FIG. 17 is a node functional block diagram of the system, where 16 is a communication control circuit of an existing LAN, 17 is a DA-WDMA communication control circuit, and 18 is a terminal (not shown) corresponding to a signal type. Signal is sent to the communication control circuit 16 of the existing LAN
Alternatively, it is connected to the DA-WDMA communication control circuit 17 (for example, a small-capacity signal is used for the communication control circuit 16 of the existing LAN).
For large-capacity signals, DA-WDMA communication control circuit 1
Interface circuit, 10 is a demultiplexer,
Reference numeral 11 is a multiplexer, and 20 is an optical transmission line. FIG. 18 is a diagram showing a network configuration of the system, 201 is a control node for managing wavelengths used for communication by each node,
202 to 205 are nodes for communicating between terminals.

First, a method of transmitting high speed data from the node 203 to the node 205 will be described. When the node 203 has a request to send high-speed data such as video, the interface circuit 18 sends a transmission request and a receiving node information signal to the existing L.
It is sent to the communication control circuit 16 of the AN, and the communication control circuit 16 of the existing LAN converts the information into an optical signal of wavelength λ _a , and the existing communication system such as token passing, TDMA (Time Division Multiple Access), slotted loop, etc. To send. The optical signal is accommodated in one optical transmission line by the multiplexer 11, is output to the optical transmission line 20, passes through the nodes 204 and 205, and reaches the control node 201. The control node 201 has a wavelength table and manages which node uses each wavelength. Therefore, first check the state of the receiving node 205, and if it is receiving, make the node 203 wait for transmission. If it is not being received, the transmission wavelength is assigned by the wavelength table, the node 205 is notified and the reception is prepared, and then the node 203 is notified and the transmission is started. The signal from the control node 201 has the wavelength λ _a and is the existing LA.
It is sent using N, enters the nodes 205 and 203, is separated from the signals of other wavelengths by the demultiplexer 10, and is input to the communication control circuit 16 of the existing LAN. The communication control circuit 16 of the existing LAN transmits the wavelength assigned to the communication control circuit 17 of the DA-WDMA system, and the DA-WDM node 203 transmits the wavelength.
The wavelength of the optical transmitter in the communication control circuit 17 of the A system is set to the assigned wavelength, the video signal is transmitted, and the node 2
In 05, the wavelength of the filter of the optical receiver in the DA-WDMA communication control circuit 17 is set to the assigned wavelength and the video signal from the node 203 is received. When the transmission from the node 203 ends, the node 203 notifies the control node 201 of the end of transmission, the control node 201 updates the wavelength table, the node 205 cancels the filter setting, and the communication ends.

Similarly, between the other nodes, the control node 201
A wavelength is assigned by and communication is performed. In this way, all wavelength allocation is centrally managed by the control node 201.

[0007]

However, in the above conventional example, since the control node manages all wavelengths, the control node is required to have high reliability and the cost of the control node becomes high. In addition, since communication is performed according to an instruction from the control node, the communication procedure becomes complicated.

Therefore, in view of the above problems, an object of the present invention is to provide a wavelength division multiplex communication system adopting a wavelength allocation method in which each node can manage wavelengths in a distributed manner without providing a control node. Especially.

[0009]

According to a wavelength division multiplex communication system of the present invention which achieves the above object, a plurality of large capacity lines using wavelength division multiplexing and a control line for controlling wavelengths or time slots of the lines are constructed. The circuit management table that indicates the wavelengths or timeslots used by the large capacity circuit is circulated to the control circuit, and the node that fetches the circuit management table selects the wavelengths or timeslots that are not in use. By allocating a line, rewriting the line management table, and performing distributed wavelength management for circulating the network, a control node is not required and a communication procedure is simplified.

[0010]

[First Embodiment] FIGS. 1 to 3 are views for explaining a first embodiment of the present invention. FIG. 1 shows the structure of a token in the token passing system, and FIG. 2 is an electrical interface section of an optical node. 3 shows a network configuration.

First, the structure of the token of the present invention will be described. In FIG. 1, PA (Preamble) is a synchronization pattern portion for extracting a clock, SD (Stata).
is the beginning of the token, FC (Frame Control) is the frame controller, and WC (Wavelength Control).
Is a line management table, ED (Ending Delim)
Itter) indicates the end of the token. The line management table WC is composed of a number of bits equal to or more than the number of wavelengths used in the network, each bit is assigned to each wavelength, and indicates whether each wavelength is currently used. For example, if the wavelength λ ₁ is used, set the bit of λ ₁ to 1,
If it is not used, set it to 0. Also, if the line is divided in time division within each wavelength, prepare a table showing the time slots, and set the used time slot to 1 and the unused time slot to 0. Good. PA, SD, FC, ED are the parts that make up the token of the existing token passing method,
The present invention does not necessarily have this configuration. Further, the line management table WC does not have to be at the position shown in FIG. 1, and may be a part of the token.

Next, the optical node and network configuration of the present invention will be described. 2 and 3, 1 is a token passing ring type communication control circuit, 2 is a wavelength division multiple access type communication control circuit by demand assignment, and 3 is an optical signal of an arbitrary wavelength among optical signals of a plurality of wavelengths. Is a wavelength filter for extracting light, 4 is an O / E converter for converting an optical signal into an electric signal, 5 is a tunable E / O converter for converting an electric signal into an optical signal of an arbitrary wavelength, and 6 is an optical receiver or electric A receiver, 7 is an optical transmitter or an electric transmitter, 8 is a coupler that splits an optical signal, 9 is a coupler that joins the optical signals, 10 is a signal of a specific wavelength among signals of a plurality of wavelengths, An optical demultiplexer that allows signals of the remaining wavelengths to pass therethrough, and a multiplexer 11 that combines optical signals of different wavelengths into one transmission line.

The wavelength filter 3 is an element or device capable of varying the transmission wavelength according to the value of the current passed through the wavelength control terminal. For example, a DFB laser structure can be used. The tunable E / O converter 5 is an element or device capable of varying the oscillation wavelength according to the value of the current flowing through the wavelength control terminal, and for example, a DFB laser or a DBR laser can be used. O
As the / E converter 4, PIN-PD or APD is used. The optical receiver 6 uses an optical receiver using an O / E converter in this embodiment, and the optical transmitter 7 uses an optical transmitter using an E / O converter. A solid line in FIG. 2 represents an optical transmission line or an optical signal, and a broken line represents an electric transmission line or an electrical signal. FIG. 3 shows a network configuration in which a plurality of nodes are connected to a loop network via a coupler and a multiplexer / demultiplexer.

Next, the communication operation will be described. Now, assuming that the image communication is performed from the node 22 to the node 25 using the wavelength λ ₁ and the large-capacity file is transmitted from the node 24 to the node 26 using the wavelength λ ₃ , the node 21
The communication operation when the user wants to perform the video communication from the node 25 to the node 25 will be described.

The node 21 acquires a token by the token passing method in order to assign the right to transmit the video and allocate the line. In the token passing method, a signal called a token that gives a data transmission right is circulated in a network, and the node that receives the token sends its own node address, destination node address and data to the transmission line 20 as a packet signal. In this method, each node receives the signal and communicates if the destination address is addressed to itself. The token shown in FIG. 1 circulates in one direction in _a ring network at _a wavelength λ _a , and at each node, a demultiplexer 10 separates and takes in optical signals of other wavelengths, regenerates and relays them, and a combiner 11 Through the optical transmission line 20.

The node 21 separates the token from the optical signals of other wavelengths (λ ₁ , λ ₃ ) by the demultiplexer 10 and receives it, and the optical receiver 6 receives the token and the token passing ring communication control circuit 1 Read. The communication control circuit 1 checks an empty wavelength from the line management table WC in the token and selects an unused wavelength. Since the wavelengths λ ₁ and λ ₃ are used here (the bit of λ ₁ and λ ₃ is 1), the wavelength λ 1
Select ₂ . Then, the address of the own node 21, the address of the destination node 25, and the information of the selected wavelength λ ₂ are written in a packet, converted into an optical signal of the wavelength λ _{a by} the optical transmitter 7, and the packet is output. It joins the optical transmission line 20. Also, the line management table WC of the token is rewritten (the bit of λ ₂ is set to 1), similarly converted to an optical signal of wavelength λ _a , and sent after the packet. Further, the communication control circuit 1 notifies the communication control circuit 2 of the wavelength division access method by demand assignment of the set wavelength λ ₂ , and the communication control circuit 2 controls the tunable E / O converter 5 to set the transmission wavelength to λ _2. Set to.

The tokens and packets sent from the node 21 are relayed through the nodes 22, 23 and 24 and then sent to the node 25.
Then, it is converted into an electric signal by the optical receiver 6 and read by the communication control circuit 1. The communication control circuit 1 reads the destination address in the packet, confirms that it is a packet addressed to its own node, and transmits the reception wavelength written in the data to the communication control circuit 2. Since the node 25 is currently receiving the video signal from the node 22, the communication control circuit 2 waits for the setting of the filter 3 until the communication ends (notifies the node 21 that it is receiving without waiting). It may be done).

When the communication from the node 22 ends, the communication control circuit 2 controls the wavelength filter 3 to set the passing wavelength to λ ₂ , and the token passing ring type communication control circuit 1
Is known to be ready to receive. When the communication control circuit 1 obtains the token, it writes the node address 25, the destination address 21, and the transmission request data into a packet, converts it into an optical signal of wavelength λ _{a by} the optical transmitter 7, and transmits the optical signal via the multiplexer 11. It is sent to the transmission line 20. The packet is sent to node 26
Is relayed and input to the communication control circuit 1 of the node 21.
The communication control circuit 1 sends a transmission request to the terminal and starts transmission of video.

Thus, the E / O converter 5 of the node 21 converts the video signal into an optical signal of wavelength λ ₂ and outputs it. The optical signal is merged into the optical transmission line by the coupler 9, is sent out to the optical transmission line 20 through the multiplexer 11, and is connected to the optical demultiplexer 10 on the optical transmission line 20 and the couplers 8 and 9. The light passes through the wave filters 11 and is transmitted on the optical transmission line 20. The signal will continue to travel around the network, but if the optical signal strength around the loop is negligible compared to the optical strength at the time of transmission, there is no problem in communication.

At each node, the token and the packet are demultiplexed by the demultiplexer 10 and the large-capacity signal is captured by the coupler 8 by branching a part thereof. Large-capacity signals of wavelengths λ ₂ and λ ₃ are currently transmitted on the network, and each node takes in the two optical signals via the coupler 8,
Since the reception wavelength of the wavelength filter 3 is already set to λ ₂ at the node 25, only the video signal of the wavelength λ ₂ is transmitted, converted by the O / E converter 4 into an electric signal and received. In addition, since no wavelength filter is set in the other nodes, large-capacity signals are not received.

Next, the procedure for ending the communication will be described. When the video communication is completed, the node 21 fetches the token,
The line management table WC is rewritten. Here the wavelength λ ₂
The bit of is set to 0 and transmitted to the optical transmission line 20. Also,
When it is necessary to notify the end of the communication to the node 25, the end information is written in the packet and the node 25 is notified. The node 25 cancels the setting of the wavelength filter 3 and terminates the communication when the video signal is not received for a certain period of time or when the communication end notification is received.

The above communication operation is similarly performed in the case of other nodes.

[0023]

[Second Embodiment] FIG. 4 is a diagram showing a network configuration of a second embodiment. In FIG. 4, 30 is an electric transmission path or an optical transmission path, and 31 to 36 are the nodes of FIG. 2, and the same parts as those in the first embodiment are designated by the same reference numerals.

In the second embodiment, the wavelength control signal and the video signal are communicated through separate loop type transmission lines, and the same operation as in the first embodiment is performed. The wavelength control signal may be an optical signal or an electric signal. When transmitting the optical signal, the transmission line 30 is an optical transmission line, the node receiver 6 is an optical receiver, and the transmitter 7 is an optical transmitter. When signals are transmitted, the transmission line 30 may be an electric transmission line, the receiver 6 may be an electric receiver, and the transmitter 7 may be an electric transmitter.

[0025]

Third Embodiment FIG. 5 is a diagram showing the network configuration of the third embodiment. In FIG. 5, 40 is a star coupler,
Reference numerals 41 to 46 denote the nodes in FIG. 2, and the same parts as those in the above embodiment are designated by the same reference numerals.

In the third embodiment, the same operation as in the first embodiment is performed by using a star type video line and a loop type network for transmitting the wavelength control signal.
Further, as in the second embodiment, the wavelength control signal may be an optical signal or an electric signal. When transmitting by an optical signal, the transmission line 30 is an optical transmission line, the node receiver 6 is an optical receiver, and the transmitter 7 is an optical signal. When an optical transmitter is used and electric signals are transmitted, the transmission line 30 may be an electric transmission line, the receiver 6 may be an electric receiver, and the transmitter 7 may be an electric transmitter.

Next, the communication operation will be described. Similar to the first embodiment, when the image communication is performed from the node 42 to the node 45 using the wavelength λ ₁ and the large capacity file is transmitted from the node 44 to the node 46 using the wavelength λ ₃ ,
A communication operation for performing video communication from the node 41 to the node 45 will be described. Similar to the first embodiment, the loop type control line is used for line allocation, and video communication is performed from the node 41 to the node 45 at the wavelength λ ₂ . When a video transmission request is transmitted from the node 45, the E / O converter 5 of the node 41
Converts the video signal into an optical signal of wavelength λ ₂ and outputs the optical signal from the node 41 to the optical transmission line 20. The optical signal is equally branched by the star coupler 40, and is distributed to all the nodes through the optical transmission line 20. Large-capacity signals of wavelengths λ ₂ and λ ₃ will be transmitted on the optical transmission line 20,
Those optical signals entering the node 45 are transmitted to the wavelength filter 3
Type, since the wavelength filter 3 has already been set to the _second receiving wavelength lambda, only the wavelength lambda ₂ of the video signal is transmitted to,
It is converted into an electric signal by the O / E converter 4 and received. It is not received because the filter 3 is not set in the other nodes.

The termination of communication operates in the same manner as in the first embodiment,
The node 41 fetches the token when the video communication is completed, rewrites the line management table WC, and the node 45
Then, when the video signal is not received for a certain period of time or when the notification of the communication end is received, the setting of the wavelength filter 3 is canceled and the communication ends.

The above communication operation is similarly performed in other nodes.

[0030]

[Fourth Embodiment] FIG. 6 is a diagram showing a network configuration according to a fourth embodiment. In FIG. 6, 14 is a bidirectional coupler,
Reference numerals 51 to 56 are nodes in FIG. 2, and the same parts as those in the above-mentioned embodiment are indicated by the same reference numerals.

In the fourth embodiment, the video line is a bus type network and the control line is a loop type network, and the same operation as in the first embodiment is performed. Further, as in the second embodiment, the wavelength control signal may be an optical signal or an electric signal. When transmitting by an optical signal, the transmission line 30 is an optical transmission line, the node receiver 6 is an optical receiver, and the transmitter 7 is an optical signal. When an optical transmitter is used and electric signals are transmitted, the transmission line 30 may be an electric transmission line, the receiver 6 may be an electric receiver, and the transmitter 7 may be an electric transmitter.

Next, the communication operation will be described. Similar to the first embodiment, when image communication is performed from the node 52 to the node 55 using the wavelength λ ₁ and a large capacity file is transmitted from the node 54 to the node 56 using the wavelength λ ₃ ,
A communication operation when performing video communication from the node 51 to the node 55 will be described. Similar to the first embodiment, the loop-type control line is used for line allocation, and video communication is performed from the node 51 to the node 55 at the wavelength λ ₂ . When the video transmission request is transmitted from the node 55, the video signal is sent to the E / E of the node 51.
The O converter 5 converts the optical signal of wavelength λ ₂ into
Output from the optical transmission line 20 via the bidirectional coupler 14.
To join. Then, it is transmitted bidirectionally through the optical transmission line 20,
A part of each node branches and is taken in through the bidirectional coupler 14, and the rest passes and is transmitted to the end of the optical transmission line 20.

Large-capacity signals of wavelengths λ ₂ and λ ₃ are transmitted on the optical transmission line 20, and those optical signals entering the node 55 are already set to the reception wavelength λ ₂ by the wavelength filter 3. Therefore, only the video signal of wavelength λ ₂ is transmitted, converted by the O / E converter 4 into an electric signal, and received. At the other nodes, the video signal is captured, but is not received because the filter 3 is not set.

The end of communication operates in the same manner as in the first embodiment,
When the video communication ends, the node 51 fetches the token, rewrites the line management table WC, and sets the wavelength filter 3 when the node 55 receives no video signal for a certain period of time or when it receives a communication end notification. Communication is terminated by releasing.

The above communication operation is similarly performed in other nodes.

[0036]

Fifth Embodiment FIG. 7 is a diagram showing the network configuration of the fifth embodiment. In FIG. 7, reference numerals 61 to 66 denote the nodes shown in FIG. 2, and the same parts as those in the above embodiment are designated by the same reference numerals. In the fifth embodiment, the video line is made into a bus type and the control line is made into a loop type network and accommodated in one optical transmission line via the demultiplexer 10 and the multiplexer 11, and the same operation as in the fourth example is carried out. Was done. In this embodiment, since the control line transmits an optical signal, the transmission line 20 uses an optical transmission line, the receiver 6 uses an optical receiver, and the transmitter 7 uses an optical transmitter.

[0037]

Sixth Embodiment FIG. 8 is a diagram showing the network configuration of the sixth embodiment. In FIG. 8, 71 to 76 are the nodes of FIG. 2, and the same parts as those in the above-mentioned embodiment are indicated by the same numbers. In the sixth embodiment, both the video line and the control line are formed into a bus network and accommodated in one optical transmission line, and the same operation as in the first embodiment is performed. In this embodiment, since the protocol of the control line is the token passing bus system, the circuit 1 in the node is a token passing bus system communication control circuit. Further, since the control signal is transmitted as an optical signal, the transmission line 20 is an optical transmission line, the receiver 6 is an optical receiver,
The transmitter 7 uses an optical transmitter.

Next, the communication operation will be described. Now, if the image communication is performed from the node 72 to the node 75 using the wavelength λ ₁ and the large capacity file is transmitted from the node 74 to the node 76 using the wavelength λ ₃ , the node 71
The communication operation when the user wants to perform video communication from the node 75 to the node 75 will be described. The node 71 acquires a token by the token passing bus method in order to assign the right to transmit the video and allocate the line. The token passing bus system constitutes a logical ring, and the order of passing tokens is determined. The token circulates in the bus type network at the wavelength λ _a , and at each node, _{a part} of the token is branched by the bidirectional coupler 14 and further separated by the demultiplexer 10 from optical signals of other wavelengths to be taken in. The node 71 sends the token to the optical receiver 6
When it is received, the communication control circuit 1 of the token passing bus system checks an empty wavelength from the wavelength table WC in the token and selects an unused wavelength. Where wavelength λ
_{Since 1} and λ ₃ are used (the bits of λ ₁ and λ ₃ are 1), the wavelength λ ₂ is selected. And own node 71
Address, destination node 75 address, and selected wavelength λ ₂ information are written in the packet, and the optical transmitter 7 transmits the wavelength λ _a
The optical signal is converted into an optical signal and output, and then merged into the optical transmission line 20 via the multiplexer 11 and the bidirectional coupler 14.

Further, the line management table WC of the token is rewritten (the bit of λ ₂ is set to 1), it is similarly converted into the optical signal of the wavelength λ _a , and it is transmitted after the packet. The token passing bus system communication control circuit 1 is a wavelength division access system communication control circuit 2 based on demand assignment.
To the setting wavelength λ ₂ and the communication control circuit 2 of the wavelength division access system controls the tunable E / O converter 5 to set the transmission wavelength to λ ₂ .

The tokens and packets sent from the node 71 enter the node 75 through the optical transmission line 20, are converted into electric signals by the optical receiver 6, and are read by the communication control circuit 1. Token passing bus system communication control circuit 1
Reads the destination address in the packet, confirms that the packet is addressed to its own node, and transmits the reception wavelength written in the packet to the communication control circuit 2 of the wavelength division access system. Since the node 75 is currently receiving the video signal from the node 72, the communication control circuit 2 waits until the communication of the setting of the filter 3 is completed (a method of notifying the node 71 that it is receiving without waiting). But it may be). Node 7
When the communication from 2 is completed, the communication control circuit 2 of the node 75
Controls the wavelength filter 3 to set the transmission wavelength to λ ₂ ,
Notify the communication control circuit 1 of the token passing bus system that reception is ready.

When the token passing bus system communication control circuit 1 obtains a token, it writes its own node address 75, destination address 71, and transmission request data into a packet, and the optical transmitter 7 converts it into an optical signal of wavelength λ _a. Multiplexer 1
1. Transmitted to the optical transmission line 20 via the bidirectional coupler 14. The packet passes through the optical transmission line 20 and is input to the communication control circuit 1 of the node 71. The communication control circuit 1 of the node 71 sends a transmission request to the terminal and starts the transmission of video. The E / O converter 5 converts the video signal into an optical signal of wavelength λ ₂ , outputs it from the node 71, and joins the optical transmission line 20 via the multiplexer 11 and the bidirectional coupler 14. Then, the light is transmitted bidirectionally through the optical transmission line 20, passes through the bidirectional couplers 14 connected on the transmission line 20, and reaches the end of the transmission line 20.

Large-capacity signals of wavelengths λ ₂ and λ ₃ are currently transmitted on the network. At each node, the two optical signals are taken in via the bidirectional coupler 14 and the demultiplexer 10, but the node 75 Then, the wavelength filter 3 has already received λ
Since it is set to ₂ , only the video signal of wavelength λ ₂ is transmitted, converted by the O / E converter 4 into an electric signal, and received. Further, since the wavelength filter 3 is not set in the other nodes, a large capacity signal is not received.

The end of communication operates in the same manner as in the first embodiment,
When the communication of the image is completed, the node 71 fetches the token, rewrites the line management table WC, and when the node 75 does not receive the image signal for a certain period of time or receives the notification of the completion of the communication, the wavelength filter 3 is set. Communication is terminated by releasing.

The above communication operation is similarly performed in other nodes.

[0045]

[Seventh Embodiment] FIG. 9 is a diagram showing a network configuration according to a seventh embodiment. In FIG. 9, 15 is an optical or electrical bidirectional coupler, 81 to 86 are nodes in FIG. 2, and the same parts as those in the above-mentioned embodiment are designated by the same reference numerals. In the seventh embodiment, the video line and the control line are made to communicate via separate bus type transmission lines, respectively, and the same operation as in the sixth embodiment is performed. Further, the wavelength control signal may be an optical signal or an electric signal. When transmitting the optical signal, the transmission line 30 is an optical transmission line, the node receiver 6 is an optical receiver, the transmitter 7 is an optical transmitter, and the coupler 15 is an optical signal. When an optical bidirectional coupler is used and electric signals are transmitted, the transmission line 30 may be an electric transmission line, the receiver 6 may be an electric receiver, the transmitter 7 may be an electric transmitter, and the coupler 15 may be an electric bidirectional coupler.

[0046]

[Eighth Embodiment] FIG. 10 is a diagram showing a network configuration according to an eighth embodiment. In FIG. 10, 91 to 96 are shown in FIG.
Node, and the same parts as those in the above embodiment are indicated by the same numbers. In the eighth embodiment, the video line is star-shaped to perform the same operation as the star-type video line of the third embodiment, and the control line is bus-type to perform the same operation as the bus-type control line of the seventh embodiment. It was done. Further, as in the seventh embodiment, the wavelength control signal may be an optical signal or an electric signal. When transmitting by an optical signal, the transmission line 30 is an optical transmission line, the node receiver 6 is an optical receiver, and the transmitter 7 is an optical signal. When the optical transmitter / coupler 15 is an optical bidirectional coupler and electric signals are transmitted, the transmission line 30 is an electric transmission line, the receiver 6 is an electric receiver, the transmitter 7 is an electric transmitter, and the coupler 15 is an electric bidirectional. You can use a coupler.

[0047]

[Ninth Embodiment] FIG. 11 is a diagram showing a network configuration of a ninth embodiment. In FIG. 11, 101 to 106 are the nodes of FIG. 2, and the same parts as those in the above-mentioned embodiment are indicated by the same numbers. In the ninth embodiment, the video line is of a loop type to perform the same operation as the loop type video line of the second embodiment, and the control line is of a bus type to perform the same operation as the bus type control line of the seventh embodiment. It was done. Further, as in the seventh embodiment, the wavelength control signal may be an optical signal or an electric signal. When transmitting by an optical signal, the transmission line 30 is an optical transmission line, the node receiver 6 is an optical receiver, and the transmitter 7 is an optical signal. When the optical transmitter / coupler 15 is an optical bidirectional coupler and electric signals are transmitted, the transmission line 30 is an electric transmission line, the receiver 6 is an electric receiver, the transmitter 7 is an electric transmitter, and the coupler 30 is an electric bidirectional. You can use a coupler.

[0048]

[Tenth Embodiment] FIG. 12 is a diagram showing a network configuration according to a tenth embodiment. Reference numerals 111 to 116 in FIG.
Node, and the same parts as those in the above embodiment are indicated by the same numbers. In the tenth embodiment, the video line is a loop type and the control line is a bus type, and the bidirectional coupler 14, coupler 8,
It is accommodated in one optical transmission line 20 via 9, and a demultiplexer 10 and a multiplexer 11 are arranged at both ends of the control line input / output unit and bus line of each node to separate both lines. Video line is second
The loop type video line and the control line of the seventh embodiment are the same as those of the bus type control line of the seventh embodiment.

In this embodiment, since the control signal is transmitted as an optical signal, the node receiver 6 uses an optical receiver and the transmitter 7 uses an optical transmitter.

[0050]

Eleventh Embodiment FIG. 13 is a diagram showing the network configuration of the tenth embodiment. In FIG. 13, 110 is an optical or electric star coupler, and 121 to 126 are nodes in FIG. 2, and the same parts as those in the above-mentioned embodiment are indicated by the same numbers. In the eleventh embodiment, the video line is a bus type network and the control line is a star type network, and the same operation as in the first embodiment is performed. Further, the wavelength control signal may be an optical signal, and when transmitting by an optical signal, the transmission line 30 is an optical transmission line,
When the receiver 6 of the node is an optical receiver, the transmitter 7 is an optical transmitter, and the star coupler 110 is an optical star coupler, in the case of transmitting an electric signal, the transmission line 30 is an electric transmission line, the receiver 6 is an electric receiver, The transmitter 7 may be an electric transmitter and the star coupler 110 may be an electric star coupler.

Next, the communication operation will be described. Similar to the first embodiment, image communication is performed from the node 122 to the node 125 using the wavelength λ ₁ , and the node 124 to the node 2
A communication operation for performing video communication from the node 121 to the node 125 when a large-capacity file is transmitted to the 16 using the wavelength λ ₃ will be described. The node 121 acquires a token by the token passing bus method in order to assign the right to transmit the video and allocate the line. Tokens circulate in a star-shaped network in a predetermined order, and when each node inputs a token addressed to itself,
It is regenerated and relayed and output to the next node. When the node 121 receives the token at the receiver 6, the communication control circuit 1 of the token passing bus system checks an empty wavelength from the line management table WC in the token and selects an unused wavelength. The wavelengths λ ₁ and λ ₃ are used here (λ ₁ and λ ₃
Since the bit of is 1), the wavelength λ ₂ is selected. The address of the own node 121 and the destination node 12
The address of No. 5 and the information of the selected wavelength λ ₂ are written in the packet, output from the transmitter 7 and sent to the transmission line 30.
In addition, the line management table WC of the token is rewritten (λ
₂ bits are set to 1) and sent after the packet.

The token passing bus type communication control circuit 1 notifies the wavelength division access type communication control circuit 2 of demand assignment of the set wavelength λ ₂ , and the wavelength division access type communication control circuit 2 tunes the tunable E / O. The converter 5 is controlled to set the transmission wavelength to λ ₂ .

The packet sent from the node 121 is
It enters the node 125 through the star coupler 110, is received by the receiver 6, and is read by the communication control circuit 1. The communication control circuit 1 reads the destination address in the packet, confirms that the packet is addressed to its own node, and transmits the reception wavelength written in the packet to the communication control circuit 2 of the wavelength division access system. Since the node 125 is currently receiving the video signal from the node 122, the communication control circuit 2 of the wavelength division access system waits until the communication of the setting of the filter 3 is completed. 121
May be notified to)).

When the communication from the node 122 is completed, the wavelength division access type communication control circuit 2 controls the wavelength filter 3 to set the passing wavelength to λ ₂ , and the token passing bus type communication control circuit 1 prepares for reception. Let you know that When the communication control circuit 1 acquires the token, it writes the own node address 125, the destination address 112, and the transmission request data into a packet, outputs it from the transmitter 7, and sends it to the transmission line 30. The packet passes through the star coupler 110 and is input to the communication control circuit 1 of the node 121. The communication control circuit 1 of the node 121 transmits a transmission request to the terminal,
Start video transmission.

The E / O converter 5 of the node 121 converts the video signal into an optical signal of wavelength λ ₂ , outputs it from the node 121, and joins the optical transmission line 20 through the bidirectional coupler 14. Then, the light is transmitted bidirectionally through the optical transmission line 20, passes through the bidirectional couplers 14 connected on the transmission line, and is transmitted to the end of the optical transmission line 20. Large-capacity signals of wavelengths λ ₂ and λ ₃ are currently transmitted on the network, and at each node, the two optical signals are taken in through the bidirectional coupler 14, but at the node 125, the wavelength filter 3 has already received wavelengths. Is set to λ ₂ , so that only the video signal of wavelength λ ₂ is transmitted, converted by the O / E converter 4 into an electric signal, and received. Further, since the wavelength filter 3 is not set in the other nodes, a large capacity signal is not received.

The end of communication operates in the same manner as in the first embodiment,
When the video communication ends, the node 121 fetches the token, rewrites the line management table, and cancels the setting of the wavelength filter 3 when the video signal is not received in the node 125 for a certain time or when the communication end notification is received. Then the communication ends.

The above communication operation is similarly performed in other nodes.

[0058]

[Twelfth Embodiment] FIG. 14 is a diagram showing a network configuration according to a twelfth embodiment. Reference numerals 131 to 136 in FIG.
Node, and the same parts as those in the above embodiment are indicated by the same numbers. In the twelfth embodiment, the video line is of a loop type and the same operation as that of the loop type video line of the second embodiment is performed.
The control line is of a star type and operates in the same manner as the star type control line of the eleventh embodiment. Also, the eleventh
Similar to the embodiment, the wavelength control signal may be an optical signal or an electric signal. When transmitting by an optical signal, the transmission line 30 is an optical transmission line, the node receiver 6 is an optical receiver, and the transmitter 7 is an optical transmitter. When the star coupler 110 is an optical star coupler and the electric signal is transmitted, the transmission line 30 is the electric transmission line and the receiver 6
Is an electric receiver, transmitter 7 is an electric transmitter, star coupler 1
10 may be an electric star coupler.

[0059]

[Thirteenth Embodiment] FIG. 15 is a diagram showing the network configuration of the thirteenth embodiment. Reference numerals 141 to 146 in FIG.
Node, and the same parts as those in the above embodiment are indicated by the same numbers. In the thirteenth embodiment, both the video line and the control line are made into a star network and accommodated in one optical transmission line 20 via the demultiplexer 10 and the multiplexer 11, and the video line is the control line of the third embodiment. Indicates that the same operation as in the twelfth embodiment is performed. In this embodiment, since the control signal is transmitted by an optical signal, the transmission line 20 uses an optical transmission line, the node receiver 6 uses an optical receiver, and the transmitter 7 uses an optical transmitter.

[0060]

[Fourteenth Embodiment] FIG. 16 is a diagram showing a network configuration according to a fourteenth embodiment. Reference numerals 151 to 156 in FIG.
Node, and the same parts as those in the above embodiment are indicated by the same numbers. In the fourteenth embodiment, the video line and the control line are respectively made to communicate through different star type transmission lines, and the same operation as in the thirteenth embodiment is performed. The wavelength control signal may be an optical signal or an electric signal. When transmitting by an optical signal, the transmission line 30 is an optical transmission line, the node receiver 6 is an optical receiver, the transmitter 7 is an optical transmitter, and a star coupler 110. Is used as an optical star coupler and the transmission line 30 is used when transmitting an electric signal.
Is an electric transmission line, the receiver 6 is an electric receiver, the transmitter 7 is an electric transmitter, and the star coupler 110 is an electric star coupler.

[0061]

Other Embodiments In each of the above embodiments, only the wavelength usage status is written in the line management table, and the sender and receiver addresses are written in the packet. The person's address may also be included.

In the above embodiment, the method of constructing the line management table for the tokens in the token passing system and allocating the lines has been described. However, the communication system is not limited to the token passing system in the present invention. It can also be applied to methods such as slotted ring and slotted bus methods that insert information into fixed-length time slots. In that case, the line management table is configured in part of the fixed-length time slots, and the node that generates the slot. It is possible to provide the function of relaying the line management table between the nodes terminating the slot and the slot and to perform the same operation as in the above embodiment.

[0063]

As described above, according to the present invention, the line management table for performing wavelength division multiplex communication is circulated on the network, and the node which takes in the line management table determines its own communication wavelength or communication time slot. By allocating the line to, the line management node is not required and the communication procedure can be simplified.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a token of the present invention.

FIG. 2 is a diagram showing a configuration of a node of the present invention.

FIG. 3 is a network configuration diagram of the first embodiment of the present invention.

FIG. 4 is a network configuration diagram of a second embodiment of the present invention.

FIG. 5 is a network configuration diagram of a third embodiment of the present invention.

FIG. 6 is a network configuration diagram of a fourth embodiment of the present invention.

FIG. 7 is a network configuration diagram of a fifth embodiment of the present invention.

FIG. 8 is a network configuration diagram of a sixth embodiment of the present invention.

FIG. 9 is a network configuration diagram of a seventh embodiment of the present invention.

FIG. 10 is a network configuration diagram of an eighth embodiment of the present invention.

FIG. 11 is a network configuration diagram of a ninth embodiment of the present invention.

FIG. 12 is a network configuration diagram of a tenth embodiment of the present invention.

FIG. 13 is a network configuration diagram of an eleventh embodiment of the present invention.

FIG. 14 is a network configuration diagram of a twelfth embodiment of the present invention.

FIG. 15 is a network configuration diagram of a thirteenth embodiment of the present invention.

FIG. 16 is a network configuration diagram of a fourteenth embodiment of the present invention.

FIG. 17 is a diagram showing a configuration of a node of a conventional example.

FIG. 18 is a diagram showing a network configuration of a conventional example.

[Explanation of symbols]

1 Token passing communication control circuit 2, 17 DA-WDMA communication control circuit 3 Variable wavelength filter 4 O / E converter 5 Variable O / E converter 6 Optical or electrical receiver 7 Optical or electrical transmitter 8, 9 Optical coupler 10 Demultiplexer 11 Combiner 14 Bidirectional optical coupler 15 Optical or electrical bidirectional optical coupler 16 Existing LAN communication control circuit 18 Interface circuit 20 Optical transmission line 21-26, 31-36, 41 ~ 46, 51-56, 6
1-66, 71-76, 81-86, 91-96, 10
1 to 106, 111 to 116, 121 to 126, 131
~ 136, 141-146, 151-156, 202-
205 node 30 optical or electrical transmission line 40 optical star coupler 110 optical or electrical star coupler 201 control node

Claims (19)

[Claims] 1. A communication network comprises a plurality of wavelength-multiplexed lines and a signal line including at least a control signal for controlling a wavelength used or a time slot used by the wavelength-multiplexed line, and in the communication system of the signal line, A packet of the line management table that indicates the wavelength used by the wavelength-multiplexed line or the time-slot information of the line that is time-division-multiplexed in the wavelength-multiplexed line is configured, and the node that takes in the packet of the line management table is not used. A line allocation method in which a wavelength or a time slot is selected, a wavelength or a time slot is used and allocated, and the line management table is rewritten so that the circuit is circulated again. 2. The line allocation according to claim 1, wherein a plurality of wavelength-multiplexed lines and a signal line including at least a signal for controlling a wavelength used or a time slot used in the wavelength-multiplexed line are accommodated in one loop type transmission line. Method. 3. The line according to claim 1, wherein a plurality of wavelength-multiplexed lines and a signal line including at least a control signal for controlling a wavelength used or a time slot used by the wavelength-multiplexed line are accommodated in separate loop type transmission lines. Assignment method. 4. The line allocation according to claim 1, wherein a plurality of wavelength-multiplexed lines are star type, and a signal line containing at least a control signal for controlling a wavelength used or a time slot used is accommodated in a loop type transmission line. Method. 5. The line allocation according to claim 1, wherein a plurality of wavelength multiplexing lines are bus type, and a signal line including at least a control signal for controlling a wavelength used or a time slot used of the wavelength multiplexing lines is accommodated in a loop type transmission line. Method. 6. A transmission line, wherein a plurality of wavelength-multiplexed lines are of a bus type, and a signal line including at least a control signal for controlling a wavelength used or a time slot used of the wavelength-multiplexed line is a loop type and accommodated in one transmission line. The line allocation method described in 1. 7. The line allocation according to claim 1, wherein a signal line including at least a plurality of wavelength-multiplexed lines and a control signal for controlling a used wavelength or a used time slot of the wavelength-multiplexed line is accommodated in one bus type transmission line. Method. 8. The line allocation according to claim 1, wherein a plurality of wavelength-multiplexed lines and a signal line containing at least a control signal for controlling a used wavelength or a used time slot of the wavelength-multiplexed line are accommodated in separate bus type transmission lines. Method. 9. The line allocation according to claim 1, wherein a plurality of wavelength-multiplexed lines are star type, and a signal line including at least a control signal for controlling a wavelength used or a time slot used of the wavelength-multiplexed lines is accommodated in a bus type transmission line. Method. 10. The line allocation according to claim 1, wherein a plurality of wavelength-multiplexed lines are loop type, and a signal line including at least a control signal for controlling a wavelength used or a used time slot of the wavelength-multiplexed line is accommodated in a bus type transmission line. Method. 11. A plurality of wavelength division multiplexing lines are loop type, and a signal line including at least a control signal for controlling a wavelength used or a time slot used of the wavelength division multiplexing line is made into a bus type and accommodated in one transmission line. The line allocation method described in 1. 12. The line allocation according to claim 1, wherein a plurality of wavelength-multiplexed lines are bus type, and a signal line including at least a control signal for controlling a wavelength used or a time slot used for the wavelength-multiplexed lines is accommodated in a star type transmission line. Method. 13. The line allocation according to claim 1, wherein a plurality of wavelength division multiplexing lines are loop type, and a signal line containing at least a control signal for controlling a wavelength used or a time slot used of the wavelength division multiplexing line is accommodated in a star type transmission line. Method. 14. The line allocation according to claim 1, wherein a signal line including at least a plurality of wavelength-multiplexed lines and a control signal for controlling a used wavelength or a used time slot of the wavelength-multiplexed line is accommodated in one star type transmission line. Method. 15. The line allocation according to claim 1, wherein a plurality of wavelength-multiplexed lines and a signal line including at least a control signal for controlling a wavelength used or a time slot used by the wavelength-multiplexed lines are accommodated in different star transmission lines. Method. 16. The circuit allocation method according to claim 1, wherein the packet of the circuit management table includes addresses of a sender and a receiver. 17. The line allocation method according to claim 1, wherein the packet of the line management table is configured as a token in the token passing system. 18. The line allocation method according to claim 1, wherein the packets of the line management table are arranged in slots in a fixed length slot system. 19. A wavelength division multiplexing communication system using the line allocation method according to any one of claims 1 to 18.