JP3428781B2 - Packet broadcasting method for network system in which communication between node devices is performed via a plurality of channels - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention is directed to multiple channels.
System for communication between node devices
A method for packet broadcasting.

[0002]

2. Description of the Related Art In recent years, various types of network systems using optical wavelength division multiplexing transmission lines using a plurality of wavelengths have been studied for the purpose of increasing the speed of networks connecting terminals with the increase in speed of terminals. It has been done. One of these is a multi-hop type in which data to be transmitted is relayed and transmitted by a node device located in the middle of a transmission source terminal and a reception destination terminal. This method is described in “WDM-Base” by Biswanath Mukherjee.
d Local Lightwave Network
s PartII: Multihop System
s "IEEE Network July (199
2) It is explained in P20-P32.

FIG. 6 shows a configuration example of a multi-hop type network system configured by using a ring type wavelength division multiplex transmission line and a hub type node device, and an example in which four node devices are connected by an optical fiber. Shows. Code 1
Reference numerals 3 to 16 denote the node devices shown in FIG. 7, to which eight terminals are connected via eight sub transmission lines, respectively. Reference numerals 17 to 20 denote optical fibers that are optical wavelength division multiplexing transmission lines.

FIG. 7 shows a configuration example of a node device of the above-mentioned multi-hop type system example. In FIG. 7, reference numeral 21
Is a control unit that controls the reading of the buffer and the transmission wavelength of the variable wavelength transmission unit. Reference numeral 22 is a buffer control unit, which controls the reading of a packet to be transmitted at the transmission wavelength of the variable wavelength transmission unit set by the wavelength control unit from the buffer. Reference numeral 23 is a wavelength control unit,
The transmission wavelength of the variable wavelength transmission means is controlled according to a predetermined transmission wavelength control pattern. Reference numeral 24 is an optical fiber which is an optical wavelength division multiplexing transmission line. Reference numeral 25 is a branching device that branches the optical signal transmitted through the optical fiber 24
Output to each fixed wavelength receiver. Reference numerals 26 to 33 are
The fixed wavelength receiving unit I to the fixed wavelength receiving unit VIII.
From fixed wavelength receiver I26 to fixed wavelength receiver VIII33
Respectively receives only packets transmitted by optical signals of one wavelength corresponding to wavelengths λ1 to λ8. Reference numerals 34 to 41 denote demultiplexing insertion units I to demultiplexing insertion units VIII, which demultiplex the packets to be transmitted to the terminal via the sub transmission path from the packet streams output from the fixed wavelength receiving units 26 to 33. It has a function of sending the packet to the terminal and inserting a packet transmitted from the terminal through the sub-transmission line into the packet stream output from the fixed wavelength receiving units 26 to 33. Reference numerals 42 to 49 denote buffers I to VIII, which have a function of temporarily storing the packets output from the separating / inserting units 34 to 41. Code 5
0 to 57 are variable wavelength transmitters I to V.
Under the control of the control unit 21, the packets output from the buffers 42 to 49 are converted into optical signals of a predetermined wavelength within the wavelength λ1 from the wavelength λ1 and the optical fiber 24 passes through the multiplexer 58. Send to. Reference numeral 58 is a multiplexer, which multiplexes the optical signals of the wavelengths λ1 to λ8 transmitted from the eight variable wavelength transmission units 50 to 57,
Emit to 4. Reference numerals 59 to 66 denote the sub transmission lines I to VIII, which serve as transmission lines for packets between the demultiplexing / inserting units 34 to 41 and the terminals. Reference numerals 67 to 74 denote terminals I to VIII connected to the node device via the sub transmission path I through the sub transmission path VIII, respectively, and receive packets output from the separation / insertion units 34 to 41, and A packet to be transmitted to another terminal is created and transmitted to the separating / inserting units 34 to 41 via the sub transmission lines 59 to 66.

FIG. 8 shows an example of the configuration of a terminal. In FIG. 8, reference numeral 75 denotes an I / F (Interface) unit, which sends a packet output from the packet processing unit to the sub transmission lines 59 to 66, and a packet input from the sub transmission line to the packet processing unit. Output. Reference numeral 76 is a packet processing unit, which refers to the terminal connection table to obtain the values of the number-of-relays display column and the value of the used wavelength designation column corresponding to the reception destination terminal, and writes them in a predetermined column of the header for transmission. The packet is assembled by adding it to the data to be processed, the header part of the received packet input via the I / F unit 75 is removed, and a predetermined receiving process is performed. Reference numeral 77 is a terminal connection table, and regarding the terminal connected to this network system, which terminal is connected to which node device, and further, that terminal is connected to the sub transmission line 59.
Connection information of the terminal such as what is the wavelength (hereinafter, reception wavelength) received by the fixed wavelength reception units 26 to 33 that output packets to the separation / insertion units 34 to 41 connected via
It has as a terminal connection table as shown in Table 1.
Reference numeral 78 denotes an input / output unit for rewriting the contents of the terminal connection table 77 without going through the network system when a new terminal is newly connected to the network system or when the connection relationship of the terminals is changed. keyboard,
It has an interface function such as a display device.

[0006]

[Table 1] FIG. 9 is a configuration example of a packet used in the above-mentioned multi-hop type system example. In FIG. 9, reference numeral 79 is
It is a relay number display column showing the number of relays required for transmission from the node device of the transmission source to the node device of the reception destination. Each of the relay node devices 13 to 16 can know whether or not the adjacent node device downstream in the transmission direction is the destination node device by subtracting the value in the relay count display field. Furthermore, whether or not this value is 0 makes it possible to know whether or not the own node device is the receiving destination. Reference numeral 80 is a used wavelength designation field, which designates a wavelength used in relay transmission. The relay number display column 79 and the used wavelength designation column 80 are header parts. As shown in Table 2, the values used in the used wavelength designation column 80 of the header section are assigned 1 to 8 as the used wavelength designation column values for the respective transmission wavelengths λ1 to λ8. Reference numeral 81 is a data portion carried by this packet.

[0007]

[Table 2] FIG. 10 is an internal configuration diagram of the separation / insertion unit I to the separation / insertion unit VIII of the node device used in the above-mentioned multi-hop type system example. Separation insertion part I34 to separation insertion part VI
All the internal configurations of II41 are the same. In FIG. 10, reference numeral 82 is a comparator, which compares whether or not the value of the relay count display column 79 of the packet output from the latch 83 is 0. If the value is 0, a separation instruction is given; The instruction is output to the demultiplexer 85.
Reference numeral 83 is a latch, which stores the number-of-relays display column 79 of the packets output from the fixed wavelength receiving units 26 to 33,
The value is output to the comparator 82. Reference numeral 84 is I /
The F unit outputs the packet output from the demultiplexer 85 to the sub transmission lines 59 to 66 and outputs the packet input from the sub transmission line to the FIFOI.
Reference numeral 85 denotes a demultiplexer, which outputs the input packet to the I / F unit 84 when the output of the comparison result of the comparator 82 is a separation instruction, and outputs it to the FIFO II when it is a relay instruction. Reference numeral 86 denotes an insertion control unit, which controls the reading of the FIFO I and the FIFO II, and instructs the selector 89 which FIFO to select, thereby receiving the packets transmitted from the sub-transmission lines 59 to 66 at a fixed wavelength. Control is performed to insert the packet stream output from the units 26 to 33. Code 87
Reference numeral 88 denotes FIFOI and FIFOII, which temporarily store the input packets and output them to the selector 89 in the order of input under the control of the insertion control unit 86. Reference numeral 89 is a selector, which selects the FIFO storing the packet signal to be output according to an instruction from the insertion control unit 86.

FIG. 11 is an internal configuration diagram of the buffers I to VIII used in the above-mentioned multi-hop type system example. The buffers I to VIII have the same internal structure. In FIG. 11, reference numeral 9
Reference numeral 0 denotes a demultiplexer, which is a used wavelength designation field 80 in the header part of the packets output from the demultiplexing insertion parts 34 to 41.
To the latch I91 and the relay number display column 79 to the latch II9.
2, the data section 81 is output to the shift register 94, respectively. Reference numeral 91 is a latch I, which stores the used wavelength designation field 80 in the header part of the packet and outputs the value to the write address counter 95 and the selector 96. Reference numeral 92 is a latch II, which stores the relay count display field 79 in the header part of the packet and outputs the value to the down counter 93. A down counter 93 is a latch II 92.
Relay number display field 7 in the header part of the packet output from
9 is subtracted and output to the selector 96. Reference numeral 94 is a shift register, which gives a desired delay to the data portion 81 of the packet output from the demultiplexer 90 and outputs it to the selector 96. Reference numeral 95 denotes a write address counter, which generates a write address of the dual port memory 98 to which the packet should be written according to the value of the used wavelength designation field 80 in the header part of the packet output from the latch I91, and sequentially writes the packet. The address signal is output to the dual port memory 98. Reference numeral 96 denotes a selector, which is used wavelength designation field 80 of the header part of the packet output from the latch I91, the value of the relay count display field 79 subtracted by the down counter 93, and the desired output from the shift register 94. By sequentially selecting the data portion 81 of the packet given the delay, the packet in which the value in the relay number display column 79 is subtracted is reconstructed and output to the dual port memory 94. Reference numeral 93 is a read address counter, which outputs an address signal for sequentially reading packets to the dual port memory 98 using the offset value output from the buffer control unit 22 in the control unit 17 as a read start address. Reference numeral 98 is
It is a dual-port memory for writing and reading packet data independently. The storage area of the dual port memory 98 is divided into eight areas according to the wavelength at which the packet should be transmitted. The storage areas I to VIII correspond to the transmission wavelengths λ1 to λ8, respectively. The start address of each area is A1, A2, A
3, A4, A5, A6, A7 and A8.

In the above-mentioned multi-hop system example, the packet processing unit 76 of the terminal that transmits data refers to the terminal connection table 77, and refers to the value of the relay count display column 79 corresponding to the destination terminal and the wavelength used. The values of the designated field 80 are obtained, these are written in a predetermined field of the header, added to the data to be transmitted to assemble a packet, and the separation / insertion units 34 to 41 of the node device are connected via the sub transmission lines 59 to 66.
To transmit.

The packet sent from the source terminal is
The demultiplexing / inserting units 34 to 41 insert the packet streams output from the fixed wavelength receiving units 26 to 33 into the buffer units 42 to 34.
At 49, the value in the number-of-relays display column 79 is subtracted, temporarily stored in the storage area corresponding to the wavelength designated in the used wavelength designation column, and then transmitted as an optical signal of a predetermined wavelength from the variable wavelength transmitters 50 to 57. And is received by the fixed wavelength receiving units 26 to 33 corresponding to the wavelength of the node device located downstream. Then, the separation / insertion units 34 to 41 detect whether or not the value of the relay count display column 79 is a value “0” indicating that it is not necessary to receive relay by another node device,
If it is not "0", it is output to the buffers 38 to 45, the value of the relay number display field 75 is subtracted, and then it is transmitted again to the downstream node device. When this relay operation is repeated and the value in the relay count display column 79 becomes “0”, the sub transmission lines 59 to 66 are transmitted.
After being separated and transmitted, the packet processing unit 76 of the terminal performs reception processing.

In this relay operation, the packet is separated / inserted based on the value in the used wavelength designation field 80 from the separation / insertion unit 34 to which the destination terminal is connected via the sub transmission lines 59 to 66.
~ 41 to output the packet to the fixed wavelength receiving unit 26 ~ 33
Is converted into an optical signal of a wavelength that is received and transmitted.

[0012]

In the above-mentioned multi-hop type system example, the terminal of the transmission source is searched in the terminal connection table, and the used wavelength designation column and the relay number display column corresponding to the destination terminal are set. By doing so, relay processing is performed in the node device based on these two values, and the packet is transmitted to the desired terminal. Therefore, compared with the case where the identification number of the destination terminal is specified as the destination address for transmission, high-speed relay processing is possible.
The terminal that transmits a packet needs to have a terminal connection table, and therefore has the following problems.

That is, in the packet broadcasting method in the above-mentioned multi-hop type system example, the terminal broadcasting the packet sequentially refers to the terminal connection table to all the terminals connected on the network system to sequentially transmit the packet. The terminal which transmits and receives the packet returns the reception response packet by referring to the terminal connection table, and the terminal which broadcasts the packet ends the broadcasting operation by confirming the reception response packet. Therefore, when the network system is newly configured or the configuration is changed, there is a problem that no packet can be broadcast because none of the terminals has a terminal connection table.

Similarly, when a new terminal is newly connected to the network system or when the connection relation of the terminal is changed, the information of the terminal whose connection has been changed is not registered, so that the broadcast packet from this terminal is not registered. Since the terminal receiving the message cannot return the reception response packet by referring to the terminal connection table, the terminal that broadcasts the packet cannot confirm the reception response packet to end the broadcast operation. was there.

Furthermore, if any of the terminals on the network system has a deficiency in the terminal connection table for some reason, the deficient terminal is connected to the terminal as described above. Since the reception response packet cannot be returned by referring to the table, there is a problem that the terminal which broadcasts the packet cannot finish the broadcasting operation by confirming the reception response packet.

The present invention is a node over multiple channels.
In a network system where communication between devices is performed
No need to respond when broadcasting a packet,
The purpose is to make it easy to identify .

[0017]

[Means for Solving the Problems] To achieve the above object,
The present invention solves the problem by using the following packet broadcasting method.

In order to achieve the above object, according to the present invention, node devices for connecting a plurality of terminal devices to a network are connected to each other by a plurality of channels, and each of the plurality of terminal devices connected to one node device comprises: A method of broadcasting a packet in a network system connected to different channels via the node device, wherein the packet transmitted by the terminal device is broadcast.
The packet is relayed by the node device on the network.
The information indicating the number of times
Send to each of several channels and receive the broadcast packet
The node device that has received the
Depending on the received broadcast packet,
Send to the terminal device connected to the channel, or
The node device to which the terminal device that transmitted the broadcast packet connects after changing the information indicating the number of times the relay packet is transmitted, transmits the broadcast packet among the broadcast packets received through the plurality of channels. When the terminal device receives the broadcast packet by transmitting the broadcast packet received through the channel connected to the terminal device to the terminal device, the packet broadcast process is terminated.

[0019]

[0020]

[0021]

[0022]

According to the present invention, node devices for connecting a plurality of terminal devices to a network are connected to each other by a plurality of channels, and each of the plurality of terminal devices connected to one node device is connected via the node device. in a network system connected to different channels Te, broadcast end
Not only can it be easily determined, but the number of relays can be specified.
Node device to which the terminal device that should receive the packet is connected
Can be specified and the node device is the address of another node device.
Packets can be broadcast without managing the packet .

[0023]

【Example】

(Embodiment 1) FIG. 1 shows a first embodiment of the present invention, which is a configuration example of a broadcast packet suitably used in the packet broadcast method of the multi-hop system example shown in FIGS. 6 to 11. is there.

In FIG. 1, reference numeral 1 is a relay number display column showing the number of relays required for transmission from a node device which is a transmission source of a broadcast packet to a node device which is a destination. At the time of relaying, each node device can know whether or not the adjacent node device downstream in the transmission direction is the destination node device by subtracting the value in the relay count display field 1. Furthermore, whether or not this value is 0 makes it possible to know whether or not the terminal connected to the own node device is the destination of reception. Reference numeral 2 is a use wavelength designation field, which designates a wavelength used in relay transmission. As shown in Table 2, 1 to 8 are assigned to the transmission wavelengths λ1 to λ8 as the values used in the used wavelength designation column 2 of the header portion. Reference numeral 3 is a packet type identification field, which is a field indicating the type of this packet, and a value indicating a broadcast packet is set as the packet type. Code 4
Are other header parts. The relay number display column 1, the used wavelength designation column 2, the packet type identification column 3, and the other header portion 4 are header portions. Reference numeral 5 is a broadcast terminal identification field, in which the terminal identification number of the broadcast terminal that is the transmission source of the broadcast packet is written. Reference numeral 6 is a data section, in which data to be broadcast is written.

FIG. 2 is an operation flowchart of the broadcast terminal that is the transmission source of the broadcast packet in the first embodiment of the present invention.

Regarding the first embodiment of the packet broadcasting method according to the present invention using the above-mentioned broadcast packet, in the node system I13 in the network system configuration example shown in FIG. 6 using the node device configuration example of FIG. A case where data is broadcast from the connected terminal I67 will be described as an example.
In the following description, the same reference numerals shown in FIG. 6, FIG. 7, FIG. 8, FIG. 9, FIG. 10 and FIG.

First, the terminal I67, which is a broadcasting terminal connected to the node device I13, sets the value of the relay number display field 1 of the header to "1" and the value of the used wavelength designation field 2 to "1".
Broadcast packets are created and these are set to the sub transmission line I5.
9 to the separation / insertion unit I34 of the node device I13. At this time, in the broadcast terminal identification column of the broadcast packet,
Write the identification number of the terminal I67. In the following description, this packet is called broadcast packet A.

I of the separation / insertion unit I34 of the node device I13
The / F unit 84 sequentially writes the broadcast packet A transmitted via the sub transmission line I59 in the FIFO I87. After writing the broadcast packet A to the FIFOI 87,
The insertion control unit 86 finds a break in the packet stream being read from the FIFO II 88, switches the input of the FIFO to be output by the selector 89 to the input from the FIFO I 87, stops the reading of the FIFO II 88, and reads the FIFO I 87. Start. After the reading of the broadcast packet A written in the FIFOI 87 is completed, the insertion control unit 86 switches the input of the FIFO to be output by the selector 89 to the input from the FIFOII 88 again, and stops the reading of the FIFOI 87. The reading of the FIFOII 88 is restarted. The broadcast packet A output from the selector 89 is input to the buffer I42.

Demultiplexer 90 of buffer I42
Outputs the used wavelength designation column 2 of the header portion of the broadcast packet A output from the separation / insertion unit to the latch I91, the relay count display column 1 to the latch II92, and the data unit 6 to the shift register 94. The latch I91 stores the used wavelength designation field 2 in the header portion of the broadcast packet A and outputs the value to the write address counter 95 and the selector 96. The latch II 92 stores the number-of-relays display column 1 in the header portion of the broadcast packet A, and stores the value in the down counter 93.
Output to. The value “1” in the relay count display field 1 of the header part of the broadcast packet A output from the latch II 92 is subtracted by the down counter 93 to become “0”, and the selector 9
6 is output. The shift register 94 gives a desired delay to the data portion 6 of the broadcast packet A output from the demultiplexer 90 and outputs it to the selector 96. The selector 96 uses the wavelength designation field 2 in the header section of the broadcast packet A output from the latch I 91, the value in the relay count display field 1 subtracted by the down counter 93, and the desired delay output from the shift register 94. By sequentially selecting the data portion 6 of the broadcast packet A given with, the broadcast packet A in which the value of the relay number display field 1 is subtracted is reconstructed and output to the dual port memory 98.

On the other hand, the write address counter 95
According to the value "1" in the used wavelength designation field 2 of the header part of the broadcast packet A output from the latch I91, the write start address of the dual port memory 98 into which the broadcast packet A should be written is set to A1, and the packets should be written sequentially. The address signal is output to the dual port memory 98.
The reconstructed broadcast packet A is input to the input port of the dual port memory 98 via the selector 96, and is sequentially written in the storage area I according to the address output from the write address counter 95. In this way, after the broadcast packet A is written in the storage area I, the transmission wavelength of the variable wavelength transmission unit I50 is set to λ1 under the control of the wavelength control unit 23 in the control unit 21,
The buffer control unit 22 in the control unit 21 outputs the offset value A1 corresponding to the storage area I to the read address counter 97 of the buffer I42. This offset value A1
Based on the above, the read address counter 97 generates an address for reading the broadcast packet A written in the storage area I by sequentially incrementing the counter, and outputs it to the dual port memory 98. The broadcast packet A is sequentially read from the output port of the dual port memory 98 by this read address, and is output to the variable wavelength transmission unit I50. Since the transmission wavelength of the variable wavelength transmission unit I50 is set to λ1, the broadcast packet A
Is transmitted from the variable wavelength transmitter I50 to the multiplexer 58 as an optical signal of the wavelength λ1, and in the multiplexer 58, another variable wavelength transmitter II51 to the variable wavelength transmitter VIII57.
Are multiplexed with optical signals of different wavelengths,
The light is emitted to the optical fiber 24 and transmitted to the node device II14 adjacent to the downstream side.

The node device II is used as an optical signal of wavelength λ1.
The broadcast packet A transmitted to the node 14 is transmitted to the node device I.
The signal is received by the fixed wavelength receiving unit I26 of I14 and output to the demultiplexing / inserting unit I34. Latch 8 of separation insertion part I34
3, the relay packet number display column 1 of the broadcast packet A output from the fixed wavelength receiving unit I26 is stored, and the value is output to the comparator 82. The comparator 82 displays the number-of-relays display column 1 of the broadcast packet A output from the latch 83.
Since the value of is 0, the demultiplexer 8
Output to 5. Upon receiving the separation instruction from the comparator 82, the demultiplexer 85 outputs the input broadcast packet A to the I / F unit 84. As a result, the broadcast packet A is output to the I / F unit 84 and transmitted through the sub transmission line I59. After that, the packet is identified by the terminal I67 which is the destination of the reception, the packet processing unit 76 reads the packet type identification field 3 of the header, and the value indicating the broadcast packet is set in this field 3, so the predetermined reception process is performed. Is performed.

After transmitting the broadcast packet A, the node device I1
The terminal I67, which is a broadcasting terminal connected to No. 3, sets the value of the relay count display field 1 in the header to "1" and sets the used wavelength specification field 2
Seven broadcast packets with the values of "2" to "8" are created, and these are transmitted to the separation / insertion unit I34 of the node device I13 via the sub transmission line I59 in the same manner as the above-mentioned broadcast packet A.

At this time, the values of the broadcast terminal identification column 5 of the 7 broadcast packets are the same as those of the broadcast packet A. Each of these seven broadcast packets is processed in the same manner as the broadcast packet A, and is output from the separating / inserting unit I34 to the buffer I42. In the buffer I42, the relay count display column 1
Value "1" is subtracted by the down counter 93 and becomes "0"
Therefore, according to the value of the used wavelength designation field 2 in the header part of the seven broadcast packets, the storage areas II to VIII are stored.
Written in. In this way, after seven broadcast packets have been written from the storage area II to the storage area VIII, they are set in the used wavelength designation column 2 under the control of the wavelength control section 23 and the buffer control section 22 in the control section 21. Variable wavelength transmitter II51 to variable wavelength transmitter VIII57 at a predetermined wavelength.
As a result, it is transmitted to the adjacent node device II14 downstream.

The seven broadcast packets transmitted to the node equipment II14 are fixed wavelength receivers II2 of the node equipment II14 according to the wavelength set in the used wavelength designation field 2.
6 is received by the fixed wavelength receiving unit VIII33,
The separation / insertion unit II34 separates the separation / insertion unit VIII41 in the same manner as the broadcast packet A, and the separated packets are output from the terminal II68 to the terminal VIII74 via the sub transmission paths. In the terminal II 68 to the terminal VIII 74, reception processing is performed in the same manner as the broadcast packet A.

In this way, the broadcast packet is transmitted from the terminal I67 connected to the node device I13 to the node device II.
The terminal I67 connected to the terminal 14 transmits the received data to the terminal VIII74.

Next, the terminal I67, which is a broadcasting terminal connected to the node device I13, sets the value of the relay number display column 1 of the header to "2" and the value of the used wavelength designation column 2 from "1" to "8". The eight broadcast packets marked with "" are created and transmitted.
At this time, the value of the broadcast terminal identification column 5 of the eight broadcast packets is the same as that of the broadcast packet A. Each of these eight broadcast packets is processed by the node device I13 in the same manner as the broadcast packet A, the value of the relay number display column 1 is subtracted from "2" to "1", and output to the node device II14.
In the separating / inserting unit of the node device II14, since the value of the relay number display column 1 is "1", it is not separated and is output to the buffer, and the value of the relay number display column 1 is "1" to "0".
From the variable wavelength transmission unit to the node device III15
Is output to. In the node device III15, since the value in the relay number display field 1 is "0", it is separated and sent from the terminal I67 to the terminal VIII74, and the same process as described above is performed. In this way, the broadcast packet is transmitted from the terminal I67 connected to the node device III15 to the terminal VII.
It is transmitted to I74 and is received and processed.

Subsequently, the terminal I67, which is a broadcasting terminal connected to the node device I13, sets the value of the relay number display field 1 of the header to "3" as described above, creates eight broadcasting packets, and transmits them. .

These eight broadcast packets are relayed by the node device II14 and the node device III15 in the same manner as described above, received by the eight terminals connected to the node device IV16, and from the terminal I67 connected to the node device IV16. The data is transmitted to the terminal VIII74 and processed for reception.

Subsequently, the terminal I67, which is a broadcasting terminal connected to the node device I13, sets the value of the number-of-relays display field 1 of the header to "4" as described above, creates eight broadcasting packets, and transmits them. To do. These eight broadcast packets are relayed by the node device II14, the node device III15, and the node device IV16 in the same manner as described above, and received by the eight terminals connected to the node device I13. At this time, from the terminal II68 connected to the node device I13 to the terminal VIII7
In 4, the broadcast packet is received and processed.

On the other hand, the terminal I67 connected to the node device I13 is the broadcasting terminal which has transmitted the broadcasting packet. In the broadcast terminal, from the value of the broadcast terminal identification column 5 of the received broadcast packet, this broadcast packet is transmitted from the own terminal, relayed by all the node devices on the network system, and made a round and returned to the own terminal. Something is found and the transmission of the broadcast packet is terminated.

In this embodiment, all nodes can receive all wavelengths and have a function of transmitting the received packet at a desired wavelength. Only one is needed.

(Embodiment 2) FIG. 3 is a second embodiment of a broadcast packet according to the present invention. In FIG. 3, reference numeral 7 is a relay terminal designation field, and designates a terminal to relay and transmit the received broadcast packet among the eight terminals connected to the node device. As a method of this designation, a wavelength (hereinafter referred to as a reception wavelength) received by a fixed wavelength reception unit that outputs a packet to a separation / insertion unit connected to a terminal via a sub transmission line is used.

FIG. 4 is an operation flowchart of the terminal which is the transmission source of the broadcast packet in the second embodiment of the present invention.

FIG. 5 is an operation flowchart of the terminal for receiving the broadcast packet in the second embodiment of the present invention.

In the second embodiment, the terminal of the sender of the broadcast packet sets the value of the relay count display field 1 to "1",
Moreover, the value of the used wavelength designation column 2 is changed from "1" to "8"
The broadcast packet is transmitted only to the terminal connected to the node device adjacent to the downstream side. The terminal receiving this broadcast packet performs the broadcast packet reception process as in the first embodiment. Further, the terminal designated in the relay terminal designation column 7 sets the value of the relay count display column 1 of the received broadcast packet to “1”, and this broadcast packet is similarly connected to the adjacent node device downstream. Sent only to those terminals. in this way,
The broadcast packet is sequentially transmitted to the terminal connected to the downstream adjacent node device by the terminal designated in the relay packet designation field of the broadcast packet, and when the transmission source terminal of the broadcast packet receives this broadcast packet. , Complete transmission of broadcast packet.

In the present embodiment, the number of broadcast packets transmitted by the terminal that is the source of the broadcast packet is reduced, and the transmission of the broadcast packet is distributed to a plurality of terminals. Therefore, the load for transmitting the broadcast packet is increased. There is an effect that can be reduced.

In the above embodiment, as shown in the flowchart of FIG. 2, after the number of relays is fixed and the wavelength designation column is changed from 1 to 8, the broadcast packet transmitted by the own terminal is received before the number of relays is increased. It was checked whether or not it was decided to end the broadcast. However, the present invention is not limited to this, and a configuration may be adopted in which the broadcast is stopped as soon as it is detected that the received packet is the broadcast packet transmitted by the own terminal. However, in this configuration, before all the broadcast packets to be transmitted are broadcast,
When the packet transmitted by the terminal itself is received (especially when the number of nodes or the number of wavelengths is small, etc.), the transmission of the broadcast packet ends at that point, and it is the destination to which the broadcast packet should be transmitted. However, the broadcast packet cannot be transmitted (especially other destinations connected to the node device to which the broadcast source is connected). So at the sender,
The packet sent to each node device at the wavelength that can be received by the own terminal (λ1 in the first embodiment) may be sent after the packet sent at another wavelength. For example,
In the first embodiment, the relay count field is fixed to a certain value,
When the transmission source terminal outputs a packet in which the used wavelength designation column is sequentially changed, the used wavelength designation column is changed to 2 → 3 → 4 → 5 → 6.
→ 7 → 8 → 1 may be set so that 1 is the last, which indicates the wavelength that can be received by the transmission source.

The same applies to the second embodiment. However, in the second embodiment, when there are two or more node devices,
The sender is supposed to receive a packet relayed by another terminal (as long as it is a means capable of processing and transmitting a packet, the terminal) as a packet to be broadcast by its own sender. It is necessary to specify to the end to relay whether or not it can receive. Alternatively, if it is decided that a terminal that receives the same wavelength as the wavelength received by the broadcast source is used as the relay terminal, this need is eliminated.

(Other Embodiments) In the above embodiments, the packet is relayed by the node device from the terminal which is the broadcast source to each node device for broadcasting. In the node device to which the terminal which is the destination is connected, the value in the relay count column is set so that the packet in which the information indicating the relay count is “0” is received. However, an appropriate value can be used for this, and the number of relays may be set by considering the node device to which the destination terminal is connected as a node device that relays to the destination terminal.

In the above embodiment, the terminals are connected to each node device from the sub transmission line through the sub transmission line.
However, not only the terminal is connected to the sub transmission path mentioned here, but also another network may be connected. Further, the present invention can be applied not only to a signal input to a node device via a sub transmission line but also to a signal generated in the node device between the node devices, in which case,
The present invention can be applied as it is by treating a node device that internally generates a signal and starts communication as a relay node device. Further, the present invention can be applied as it is even when the destination of the packet is not the sub-transmission line connected to the node device (the terminal connected thereto) but the node device itself. Further, in each of the above embodiments, an example in which a plurality of channels are configured with different wavelengths has been described, but the invention of the present application is not limited thereto, and the transmission channel may be an electrical signal other than the wavelength multiplexing as in the above embodiments. In the above, various types such as frequency multiplexing and spatial multiplexing in which a plurality of transmission lines are bundled can be used. Further, the term “multiplexing” used here is logical, and it is not necessary to physically multiplex a plurality of channels in one transmission line or bundle the transmission lines, and use, for example, space as a transmission line. It is also possible to obtain a plurality of channels by wavelength multiplexing or the like.

[0051]

As described above, according to the present invention, node devices connecting a plurality of terminal devices to a network are connected to each other by a plurality of channels, and each of the plurality of terminal devices connected to one node device is , in a network system connected to different channels through the node device, not only it can easily determine the end of the broadcast,
By specifying the number of relays, the terminal device that should receive the packet
Since the node device to connect can be specified, the node device
Packets without managing the addresses of other node devices
Can be broadcast and the system configuration can be easily changed.
You can do it .

[0052]

[Brief description of drawings]

FIG. 1 is a diagram showing a structure of a broadcast packet according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an operation of a terminal which is a transmission source of a broadcast packet according to the first embodiment of the present invention.

FIG. 3 is a diagram showing the structure of a broadcast packet according to a second embodiment of the present invention.

FIG. 4 is a diagram showing an operation of a terminal which is a transmission source of a broadcast packet according to a second embodiment of the present invention.

FIG. 5 is a diagram showing an operation of a terminal for receiving a broadcast packet according to the second embodiment of the present invention.

FIG. 6 is a diagram showing an example of a multi-hop network system.

FIG. 7 is a diagram of a configuration example of a node device used in an example of a multi-hop type network system.

FIG. 8 is a diagram of a configuration example of a terminal used in an example of a multi-hop type network system.

FIG. 9 is a diagram showing a configuration example of a packet used in an example of a multi-hop type network system.

FIG. 10 is a diagram showing a configuration example of a separation / insertion unit of a node device used in an example of a multi-hop type network system.

FIG. 11 is a diagram showing a configuration example of a buffer of a node device used in an example of a multi-hop type network system.

[Explanation of symbols]

1 Relay frequency display column 2 Use wavelength designation column 3 Packet type identification field 5 Broadcasting terminal identification column 6 data 7 Relay terminal specification field 13-16 node device 21 Control unit 22 Wavelength control unit 23 Buffer Control Unit 26-33 Fixed wavelength receiver 34-41 Separation insertion part 42-49 buffer 50-57 Variable wavelength transmitter 59 to 66 Sub transmission line 67-74 terminals 82 Comparator 83, 91-92 Latch 84 I / F section 85, 90 Demultiplexer 86 Insertion control unit 87-88 FIFO 89, 96 selector 93 down counter 94 shift register 95 write address counter 97 Read address counter 98 dual port memory

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ identification code FI H04L 12/28 H04L 11/00 330 12/42 12/46 (58) Fields investigated (Int.Cl. ⁷ , DB name) H04L 12/56 H04J 14/00 H04L 12/28 H04L 12/42

Claims (4)

(57) [Claims] 1. A node device for connecting a plurality of terminal devices to a network is connected to each other by a plurality of channels, and 1
Each of the plurality of terminal devices connected to one node device is a method of broadcasting a packet in a network system connected to different channels via the node device, and broadcasts the packet transmitted by the terminal device. In this case, the information indicating the number of times the broadcast packet is relayed by the node device on the network is added to the broadcast packet and transmitted to each of the plurality of channels, and the node device receiving the broadcast packet is The broadcast packet received is transmitted to a terminal device connected to the reception channel of the broadcast packet, or the information indicating the number of times the relay is received is changed and then relayed, Is transmitted by the node device connected to the terminal device that has transmitted the Of the packets, when the terminal device receives the broadcast packet by transmitting the broadcast packet received through the channel connected to the terminal device that transmitted the broadcast packet to the terminal device, the packet broadcast process is terminated. A packet broadcasting method characterized by the above. 2. The packet broadcasting method according to claim 1, wherein the change of the information indicating the number of times relay is received includes rewriting the information to indicate the number of times relay is received after that. 3. The packet broadcasting method according to claim 1, wherein information indicating a terminal device that has transmitted the broadcast packet is added to the broadcast packet. 4. The packet broadcasting method according to claim 1, wherein each of the plurality of channels performs optical communication of different wavelengths.