JP2003198577A - Data transmission equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate necessity to physically lay a plurality of transmission lines again when constructing a plurality of networks. <P>SOLUTION: In the data transmitter for connecting respective transmitting/ receiving apparatuses such as a plurality of computers or peripheral devices via a LAN and exchanging data therebetween, each of the transmitting/receiving apparatuses is made into multi-mode transmitting/receiving apparatus and a transmission line to be used for the LAN is made into multi-mode optical fiber cable capable of transmitting data onto that transmission line in a plurality of modes. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a data transmission device.

[0002]

2. Description of the Related Art Generally, distributed computers and peripheral devices share resources such as data and programs by being connected by a LAN, and as a result, data can be exchanged quickly. In addition, the form of LAN has been diversified due to higher performance of workstations and personal computers and transmission of multimedia data. Along with these advances, LANs have become required to have high speed and high efficiency, and flexibility to change has been required, and LANs adopted as a backbone for traffic and energy control are required to have high reliability. .

Therefore, it is necessary to add a new one to the conventionally laid LAN or to make the LAN redundant to improve the reliability. LA with such a complicated configuration
Generally, a plurality of cables are physically laid when constructing N or adding a new network to an existing network.

A conventional example of a data transmission device will be described below with reference to FIG. In FIG. 13, the conventional data transmission apparatus is composed of a plurality of transmission lines Al and a station ST (stoke computer, workstation, personal computer, etc.) connected thereto. The data transmission device configured as described above requires a plurality of transmission devices, and thus has a problem in mounting the device and has a problem such as securing a place for installation. There was also little flexibility in change.

[0005]

In the above-mentioned conventional data transmission apparatus, when constructing a plurality of LANs, it was a problem that a plurality of cables had to be physically laid. The present invention has been made to solve the above problems, and an object of the present invention is to provide a highly efficient and highly reliable data transmission device that can physically provide a plurality of transmission lines with a single transmission line. I am trying.

[0006]

A data transmission apparatus according to [Claim 1] of the present invention connects transmission / reception devices such as a plurality of computers and peripheral devices via a LAN, and transmits / receives data between them. In the data transmission apparatus to be performed, each transmission / reception apparatus is a multimode transmission / reception apparatus, and the transmission path used for the LAN is a multimode optical fiber cable capable of transmitting data in a plurality of modes on the transmission path. In the data transmission device having the above-mentioned configuration, physically 1
By laying one transmission line, it is possible to virtually lay a plurality of physical transmission lines.

A data transmission apparatus according to [Claim 2] of the present invention is the data transmission apparatus according to [Claim 1], in which a plurality of single mode transmissions for transmitting data in a specific mode in place of the multimode transmission apparatus at the transmitting end A device and an assembling device for collecting and transmitting data from each of the transmitting devices on a multimode optical fiber cable. In the data transmission device having the above configuration, since the transmission devices can be multiplexed, the reliability of the device can be improved.

A data transmission apparatus according to [Claim 3] of the present invention is the apparatus according to [Claim 1], in which the receiving end receives data on a multimode transmission line instead of the multimode receiving apparatus and divides the data for each mode. And a plurality of receiving devices for receiving the respective data. In the data transmission device having the above configuration, since the receiving device can be multiplexed, the reliability of the device can be improved.

A data transmission device according to [Claim 4] of the present invention is a data transmission device in which a plurality of unit transmission / reception devices are connected via a bus network, wherein the unit transmission / reception device is one mode out of a plurality of modes. The multi-mode receiving device and the data transmitting device for selecting and transmitting data. In the data transmission device with the above configuration, full-duplex communication (independent channel and reception channel are prepared between all stations connected to the network so that transmission and reception can be performed simultaneously) ) Is possible.

In the data transmission apparatus according to [Claim 5] of the present invention, in [Claim 4], each of the unit transmission / reception apparatuses is connected to a bus type network via a coupler. In the data transmission device having the above configuration, even if one station connected to the network fails, it does not affect other stations, and it is possible to easily add or delete stations.

According to a sixth aspect of the present invention, in the data transmission apparatus according to the fourth aspect, each of the unit transmitting / receiving devices is connected to a ring type network. The data transmission device having the above configuration can be used from a small-scale to a large-scale system construction due to its structural features.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 is a block diagram showing a first embodiment of a data transmission apparatus according to the present invention. In FIG. 1, reference numeral 1 denotes a multimode transmission device, 2
Is also a multimode receiving device, and the data transmitting device is configured by connecting the multimode receiving devices between them by the multimode optical fiber transmission line 3.

A multimode optical fiber used as a transmission line is known per se, and when transmitting a signal to a receiving device at the other end while reflecting light inside the optical fiber cable, a plurality of reflection angles are required. It is possible to let the light which it has pass through the inside of one cable. Each light having a different reflection angle is called a mode, and is hereinafter referred to as a multimode transmission line.

Therefore, in the present embodiment, since the multimode transmission line 3 is used, the multimode transmitter 1 and the multimode receiver 2 are provided at each end correspondingly. In FIG. 1, modes 1, 2,
, N represents the difference in the above-mentioned reflection angles. And in this embodiment, this kind of multimode optical fiber transmission line,
It is used as a LAN transmission line connecting computers and peripheral devices.

Therefore, as a function, a signal passing through the transmission line travels while refracting in the transmission line. At this time, since a number of propagation mode signals can propagate in the transmission line in the multimode transmission line, a wide band is obtained. Suitable for signal propagation.

According to the present embodiment, it is possible to physically lay out a plurality of transmission lines with one transmission line physically, and easily increase or decrease the number of transmission lines by adding / deleting the propagation mode to be transmitted. can do.

(Second Embodiment) FIG. 2 is a block diagram showing a second embodiment. 2, parts having the same functions as those in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted. In this embodiment, a plurality of transmitters are provided for multiplex transmission. Therefore, the single mode transmitter (1
-1, 1-2, ..., 1-N) are provided, and a collecting device 4 is provided for receiving signals of a plurality of modes from them and collecting and transmitting the signals on the plurality of mode transmission lines 3. .

According to the present embodiment, by providing a plurality of single-mode transmitters, even if one device fails, another device can continue transmission, thus improving reliability. Therefore, it is possible to replace and repair only the faulty device without stopping the transmission, and it is possible to improve the transmission efficiency. Further, in the conventional transmission device, it is difficult to determine whether the transmission device has a failure or the transmission path has a failure.
Since there are a plurality of transmission devices, the judgment can be easily made.

(Third Embodiment) FIG. 3 is a block diagram showing a third embodiment. 3, parts having the same functions as those in FIG. 1 are assigned the same reference numerals and explanations thereof will be omitted. In this embodiment, a plurality of receiving devices are provided to enable individual single-mode reception. For that purpose, a plurality of single mode receivers (2-1, 2-2, ..., 2-N) are provided, and a dividing device 5 is connected to the multimode transmission line 3 for each divided mode. Each single receiving device is adapted to receive.

According to the present embodiment, by using a plurality of receiving devices, a sound device can continue to receive even if one device fails, so that reliability can be improved and transmission can be improved. It is possible to replace and repair only the failed device without stopping the operation. Therefore, the transmission efficiency can be improved. Further, in the conventional transmission apparatus, it is difficult to judge whether or not the failure of the transmission apparatus is the failure of the transmission line, but since there are a plurality of transmission apparatuses, the judgment can be easily performed.

(Fourth Embodiment) FIG. 4 is a block diagram showing a fourth embodiment. FIG. 4 (a) is an overall view showing a connection relationship between stations ST, and FIG. It is a block diagram of each station unit. In this embodiment, as shown in (a), each station ST
1 to ST5 are connected via a bus type network 6.

On the other hand, (b) is a block diagram of each station ST,
The data transmission unit includes a transmission device 1-1 that selects one mode from a plurality of modes and transmits data, and a multimode reception device 1. In addition, each of the above devices is a single mode transmission line 6
-1 and the multimode transmission line 6-2. That is, (a)
The bus network 6 comprises a single mode transmission line 6-1 and a multimode transmission line 6-2. Each station connected to this network transmits data on a transmission line in a different transmission mode.

According to this embodiment, each station can simultaneously receive data in all modes flowing on the transmission path. Therefore, full-duplex communication can be realized between all the stations without collision of the data from the respective stations on the transmission path, and the transmission efficiency can be improved.

(Fifth Embodiment) FIG. 5 is a block diagram showing a fifth embodiment. In FIG. 5, the same functional portions as those in FIG. Omit it. In this embodiment, even if one station connected to the network fails, the other stations are not affected. As a configuration for this, a coupler (a device that branches a transmission line) is provided to each station. ) 7 is used to share the transmission line.

Therefore, the data transmitted from a certain station is sent out on the bus, and the receiving side fetches only the data addressed to its own address. By using the bus type connection mode, even if one station connected to the network fails, other stations are not affected, and addition or deletion of stations can be facilitated.

(Sixth Embodiment) FIG. 6 is a block diagram showing a sixth embodiment. In the present embodiment, the data transmission device of each station is connected to the ring type transmission line 8, and all stations connected to this transmission line share this transmission line. Therefore, the data transmitted from a certain station is transmitted in a fixed direction, goes around each station, and finally returns to the transmitting station.

Each station checks whether the data transmitted from a certain station is the data addressed to itself, and if it is addressed to the own station, it is taken in and marked with reception completion and transferred. Otherwise, it is transferred to the next station. Transfer as is. The data that has gone around the ring finally returns to the transmitting station, where the reception state is confirmed and the communication ends.

According to the present embodiment, by using the ring type connection form, the data signal is relayed to the stations one after another, so that the signal can reach a wide range, from small to large systems. It can be used until construction.

(Seventh Embodiment) FIG. 7 is a block diagram showing a seventh embodiment. In this embodiment, a device (SV) 9 having a centralized control function of information is placed at the center, and each station having a host computer or terminal is radiated (star).
The connection form is such that the devices are connected in a state of shape and information is transmitted and received. Therefore, all the data transmitted by the connected stations are collected in the centralized control device, and the data are transmitted from there to each station.

According to the present embodiment, by using the star type connection form, it is possible to easily add or delete a station connected to the network.

(Eighth Embodiment) FIG. 8 is a block diagram showing an eighth embodiment. In the present embodiment, a data transmission device having a bus type as a network connection form uses a contention system as an access control system. The access control method determines at what timing data should be sent when it is sent on the transmission path, and what kind of control should be performed when many stations share the transmission path. It is a thing.

The access control method of this embodiment is performed in the following procedure. Investigate whether the transmission path of transmission mode N is free. If it is free, transmission starts in mode N. At this time, multiple stations may start transmission. If not available, set the transmission mode to N + 1 and go again. A collision occurs. You need to retransmit. Detects a collision. Transmission mode is N
Set it to +1 and go again. Repeat ~ until transmission is successful.

According to the present embodiment, by using this access control method, it is possible to retransmit in another mode without waiting for data transmission, so that transmission efficiency can be improved.

(Ninth Embodiment) FIG. 9 is a block diagram showing a ninth embodiment. In the present embodiment, in the data transmission device having the ring type as the network connection form, the token passing system is used as the access control system. The access control method of this embodiment is performed in the following procedure.

[Example of transmission from ST1 to ST3] A free token (state with no transmission data) circulates in mode N of the ring type transmission line. When ST1 receives the free token, it changes it to a busy token (in use) and sends it to the next station in the form of a packet with a destination (ST3), a sender name (ST1) and data.

Packets are transferred from station to station and are sent to the destination station. When ST3 receives the data, it marks the data as received, changes the transmission mode to N + 1, and sends it to the next station. Also, a free token is transmitted to mode N.
When the data packet returns to ST1, reception confirmation is performed in ST1.

According to the present embodiment, by using this access control method, the received packet does not interfere with the data transmission, so that the transmission efficiency can be improved.

(Tenth Embodiment) FIG. 10 is a block diagram showing a tenth embodiment. In this embodiment, a plurality of stations ST1 to ST5 are connected on the transmission line, and ST
The stations ST1, ST3, ST4 use N as the transmission mode, and belong to the network N separated from the networks in the other transmission modes.

Similarly, ST2 and ST5 use N + 1 as the transmission mode and belong to the independent network N + 1. As described above, as many networks as the number of transmission modes can exist in a network having a transmission path using the data transmission device of the present embodiment.

According to the present embodiment, when ST4 tries to join the network N + 1 as shown by the broken line, it becomes possible to join by switching the transmission mode from N to N + 1. The network configuration can be easily changed because it does not involve the change of the connection.

(Eleventh Embodiment) FIG. 11 is a block diagram showing the eleventh embodiment. The present embodiment has a network in which different transmission methods are assigned to a plurality of transmission modes of the transmission device. As an example, a packet switching system is used for the transmission mode N and a circuit switching system is used for the transmission mode N + 1.

When ST1 and ST4 try to perform transmission by the circuit switching method using the transmission mode N + 1, the mode is notified to each station so that it cannot be used by other stations. Then, when ST2, ST3, and ST5 perform data transmission by the packet switching method in mode N, N + 1 cannot be used as a mode for collision avoidance, and therefore mode N + 2 is used.

According to the present embodiment, a plurality of transmission methods can be assigned by giving priority to the use of the transmission mode due to the difference in the transmission method and preventing the transmission in the other modes from interfering with each other. .

(Twelfth Embodiment) FIG. 12 is a block diagram showing a twelfth embodiment. In FIG. 12, FIG.
The same functional parts as in FIG. In the present embodiment, among the plurality of stations connected to the network, a station that can exclusively use a certain mode of the multimode transmission line is provided.

FIG. 12 shows, as an example, the case where the access control system based on the contention system is used. That is, ST
2 may process data from another station and send the result to ST4 at a certain time, so that the access control method causes a collision and cannot send at the correct time. There is a nature.

According to this embodiment, a certain mode is set to ST.
By allocating exclusively to 2 and ST4, other stations will not be able to send data in that mode and S
T2 can transmit data to ST4 accurately without causing a collision.

[0047]

As described above, according to the present invention, it is not necessary to physically lay a plurality of transmission lines in order to build a plurality of networks, so that the place and work involved in the laying can be reduced. Therefore, it is possible to provide a data transmission device capable of flexibly supporting various transmission methods.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment of a data transmission device according to the present invention.

FIG. 2 is a diagram showing a second embodiment of a data transmission device according to the present invention.

FIG. 3 is a diagram showing a third embodiment of a data transmission device according to the present invention.

FIG. 4 is a diagram showing a fourth embodiment of a data transmission device according to the present invention.

FIG. 5 is a diagram showing a fifth embodiment of a data transmission device according to the present invention.

FIG. 6 is a diagram showing a sixth embodiment of a data transmission device according to the present invention.

FIG. 7 is a diagram showing a seventh embodiment of a data transmission device according to the present invention.

FIG. 8 is a diagram showing an eighth embodiment of a data transmission device according to the present invention.

FIG. 9 is a diagram showing a ninth embodiment of a data transmission device according to the present invention.

FIG. 10 is a diagram showing a tenth embodiment of a data transmission device according to the present invention.

FIG. 11 is a diagram showing an eleventh embodiment of a data transmission device according to the present invention.

FIG. 12 is a diagram showing a twelfth embodiment of a data transmission device according to the present invention.

FIG. 13 is a diagram showing a configuration of a LAN using a conventional data transmission device.

[Explanation of symbols]

1 Multimode transmitter 2 Multimode receiver 3 Multimode optical fiber transmission line 4 Collecting device 5 division device 6-bus network 6-1 Single mode transmission line 6-2 Multimode transmission line 7 combiner 8 ring type transmission line 9 Equipment with centralized control function

Claims (6)

[Claims] 1. A data transmission device, comprising: a plurality of computers, peripheral devices, and other transmission / reception devices connected via a LAN, and data transmission / reception therebetween, wherein each transmission / reception device is a multimode transmission / reception device. A data transmission device, wherein the transmission line used for the LAN is a multimode optical fiber cable capable of transmitting data in a plurality of modes on the transmission line. 2. The data transmitting apparatus according to claim 1, wherein a plurality of single mode transmitting apparatuses for transmitting data in a specific mode instead of the multimode transmitting apparatus are provided at a transmitting end, and data from each of the transmitting apparatuses. And a collecting device for collecting and transmitting the data on a multimode optical fiber cable. 3. The data receiving device according to claim 1, wherein the receiving end receives the data on the multimode transmission line instead of the multimode receiving device, divides each mode, and transmits to each of the plurality of transmission lines. And a plurality of receiving devices for receiving each of the data, the data transmitting device. 4. A data transmission device in which a plurality of unit transmission / reception devices are connected via a bus network, wherein the unit transmission / reception device selects one mode from a plurality of modes and transmits data. A data transmission device comprising a multi-mode receiver. 5. The data transmission device according to claim 4, wherein each of the unit transmission / reception devices is connected to a bus type network via a coupler. 6. The data transmission device according to claim 4, wherein each of the unit transmission / reception devices is connected to a ring type network.