JP2002353997A - Network connection device and data transmission method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress increase in the amount of traffic in a network by changing data transmission processing, depending on the traffic amount in the network. SOLUTION: A network connection device is provided with a DMX communication section 21, that receives dimmer control data of a data form which confirms with the dimmer control protocol, a transmitter side protocol conversion section 22 that converts the dimmer control data received into a packet, conforming with the data transmission protocol to be transmitted by a LAN network 5, a traffic detection section 32 that acquires the traffic state of the LAN network 5, and a transmission reception control section 31 that selects the data transmission system for transmission of the converted packet through the LAN network 5, and transmits the packet converted in compliance with the selected data transmission system to the LAN network 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a network connection device, a data transmission method, and a program for transmitting data between networks having different protocols when transmitting control data for controlling a load device.

[0002]

2. Description of the Related Art Conventionally, the DMX512 standard has been known as a protocol for controlling dimming of a lighting device. The DMX512 standard uses a transmission method in which a dimming console operated by a user transmits 512 bytes of dimming control data every 24 msec. One byte of 512 bytes corresponds to dimming control data of each lighting device. Stipulates that

[0003] Also, UDP (User Datagram Protocol)
/ IP (Internet Protocol) is a LAN (Local Area)
Network (TCP) is a protocol used with a network that conforms to the TCP standard.
tocol) / IP in that communication is performed according to IP, but no connection is established.
For this reason, even if the transmitted packet is lost in the network and does not reach the destination device, delivery confirmation and retransmission control are not performed with the destination device. Therefore, when using UDP / IP, even if a packet collision or the like occurs in the network, it is presently the responsibility of the user to confirm whether or not the transmission has been completed.

[0004] On the other hand, in the case of TCP / IP, there is an inconvenience that the increase in traffic volume is accelerated due to delivery confirmation and retransmission control, but the network traffic volume is large and packet collisions are likely to occur. Even in a network, by performing retransmission control, a packet can be reliably transmitted from a packet transmitting side to a destination device.

Further, the conventionally known full-duplex system is a transmission system in which transmission data and reception data are simultaneously bidirectionally communicated by separately setting a transmission port and a reception port. Avoid collisions with data.

The half-duplex system is a transmission system in which the data transmission direction is alternately changed between transmission data and reception data. Although a collision occurs between the transmission data and the reception data, the half-duplex system communicates more than the full-duplex system. It has the advantage of high speed.

In a conventional dimming system, DMX51
2 is connected to a DMX device that transmits data according to the standard, and is connected to a network that transmits data according to the LAN standard.
In a network connection device that converts packets into packets conforming to the N standard, the communication speed is usually given the highest priority in many cases.
Half-duplex in a network conforming to the LAN standard,
Communication using UDP / IP has been performed.

[0008]

By the way, DMX51
2 standard, as shown in FIG.
1 to generate the dimming control data, and
It is a protocol suitable for a closed environment such as a dimming system that transmits dimming control data to a plurality of DMX devices 103 that are lighting devices via the illuminator, but is widely known for communication outside the dimming system. LAN standards are preferred.

Therefore, as shown in FIG. 7, a DMX 51 is provided between the DMX controller 101 and the DMX device 103.
2, a transmission-side protocol converter 104 that converts dimming control data according to the LAN standard into a packet according to the LAN standard;
A receiving-side protocol converter 105 for converting a packet conforming to the AN standard into dimming control data conforming to the DMX standard is provided, and a LAN network 106 connects the transmitting-side protocol converter 104 and the receiving-side protocol converter 105 to each other. A connected dimming system has been proposed.

[0010] However, the DMX512 standard requires 24 msec.
Is a protocol for transmitting dimming control data every time.
In order to transmit a packet every 24 msec even in the AN network 106, the transmission-side protocol converter 104
In addition, UDP was mounted on the receiving-side protocol converter 105 to perform data transmission.

In this case, no problem occurs when, for example, the number of DMX devices 103 is small and the traffic volume in the LAN network 106 is small, but for example, when the number of DMX devices 103 is large and the traffic volume in the LAN network 106 is large. Even in this case, it is necessary to transmit the packet every 24 msec, and there is a problem that the traffic volume is further increased.

In view of the above, the present invention has been proposed in view of the above-mentioned circumstances, and a network capable of suppressing an increase in the traffic volume of a network by changing a data transmission process according to the traffic volume in the network. It is an object to provide a connection device, a data transmission method, and a program.

[0013]

The invention according to claim 1 is
In order to solve the above-mentioned problem, in a network connection device connected to a control device for controlling a plurality of load devices and transmitting control data from the control device to a network, the control device has a data format according to a control protocol. Transmitting and receiving means for receiving the control data transmitted from the network, data converting means for converting the control data received by the transmitting and receiving means into packets conforming to a data transmission protocol transmitted over the network, and acquiring the traffic state of the network A traffic state acquisition unit, a transmission method control unit that selects a data transmission method when transmitting the packet converted by the data conversion unit on the network based on the traffic state acquired by the traffic state acquisition unit; Data selected by transmission method control means Packets converted by said data conversion means in accordance with transmission method and a transmission control means for controlling said transmitting and receiving means to deliver to the network.

[0014] In the invention according to claim 2, the traffic state acquiring means is connected to a plurality of network connection devices and relays packets from the plurality of network connection devices, and collision detection for detecting packet collisions. Means for receiving a collision detection signal from the collision detection means by the transmission / reception means and counting the collision detection signal received by the transmission / reception means. Then, the counter value of the collision counter is acquired as a traffic state, and the transmission method control means selects a data transmission method based on the increment of the counter value by the collision counter acquired by the traffic state acquisition means.

[0015] In the invention according to claim 3, the traffic status acquisition means is a destination of a packet transmitted from the transmission / reception means, and has another traffic connection device having a traffic counter for counting the amount of received data. Is connected via the network, the counter value from the traffic counter is received by the transmission / reception means at predetermined intervals, and is obtained as a traffic state, and the transmission method control means is obtained by the traffic state obtaining means. A data transmission method is selected based on the increment of the counter value by the traffic counter.

According to a fourth aspect of the present invention, there is provided a network connection device connected to a control device for controlling a plurality of load devices and transmitting control data from the control device to a network. Transmitting / receiving means for receiving control data transmitted from the control device in a data format according to a control protocol, and data conversion for converting the control data received by the transmitting / receiving means into a packet according to a data transmission protocol transmitted over the network Means, data content determining means for determining the data content of the control data received by the transmitting / receiving means, data content of the control data received by the transmitting / receiving means at a first time, and the transmitting / receiving means following the first time If it is determined by the data content determination means that the data content of the control data received in is different, Included in the serial converted by the data conversion unit packet, and a transmission control means for controlling the transmission and reception means to the control data received by the receiving means in the following the first time sent to the network.

In the invention according to claim 5, the transmission / reception means establishes a connection with a network connection destination of a packet transmission destination in accordance with a communication protocol for performing packet retransmission control.

In the invention according to claim 6, the transmission / reception means performs transmission / reception of packets by a full-duplex method.

The invention according to claim 7 further comprises a traffic state acquisition means for acquiring the traffic state of the network, wherein the transmission control means is adapted to transmit and receive the traffic information when the traffic amount acquired by the traffic state acquisition means is small. And controls the transmitting / receiving means so that all control data received by the data converting means and converted by the data converting means are transmitted to the network.

According to an eighth aspect of the present invention, there is provided a data transmission method for transmitting control data from a control device for controlling a plurality of load devices to a network in order to solve the above-mentioned problems. Receiving the control data transmitted from the control device, transmitting the control data to the destination network connection device, acquiring the traffic state of the network, and transmitting the received control data over the network. A data transmission protocol for transmitting the converted packet on the network based on the obtained traffic state, and converting the packet in accordance with the selected data transmission protocol. To the network.

According to a ninth aspect of the present invention, in the data transmission method for transmitting control data from a control device for controlling a plurality of load devices to a network, the control data transmitted from the control device in a data format according to a control protocol is provided. When receiving the data and transmitting the control data to the destination network connection device, the data content of the received control data is determined, and the received control data is transmitted according to a data transmission protocol for transmitting the control data over the network. When the data content of the previously received control data and the data content of the control data received this time are determined to be different, the control data included in the converted packet and the control data received this time are transmitted to the network. To send to.

According to a tenth aspect of the present invention, there is provided a data transmission program for executing a data transmission method for transmitting control data from a control device for controlling a plurality of load devices to a network. Receiving control data transmitted from the control device in a data format according to a control protocol, and acquiring the network traffic state when transmitting the control data to the destination network connection device; The control data is converted into a packet according to a data transmission protocol transmitted on the network, and a data transmission method for transmitting the converted packet on the network is selected based on the obtained traffic state. The packet converted according to the data transmission method To execute a process of sending a click on the computer.

According to an eleventh aspect of the present invention, in a data transmission program for executing a data transmission method for transmitting control data from a control device for controlling a plurality of load devices to a network, a data format in accordance with a control protocol is provided. When receiving the control data transmitted from the control device and transmitting the control data to the destination network connection device, the data content of the received control data is determined, and the received control data is transmitted to the network connection device. In addition to converting to a packet in accordance with the data transmission protocol to be transmitted in, when it is determined that the data content of the previously received control data and the data content of the control data received this time are different, it is included in the converted packet, The process of sending the control data received this time to the network is executed by the computer. That.

[0024]

Embodiments of the present invention will be described below with reference to the drawings.

The present invention is applied to a dimming system configured as shown in FIG. 1, for example.

[Configuration of Light Control System] As can be seen from FIG. 1, the light control system is a DMX operated by a user.
Device operating devices 1A and 1B (hereinafter, simply referred to as “DMX device operating device 1”), a plurality of network connecting devices 2A to 2E, and a switching device 3
And a plurality of LAN (Local Area Network) devices 4A to 4A
D is connected to a LAN network 5 that performs data transmission according to, for example, a LAN standard called Ethernet (registered trademark) and a network connection device 2B.
And a plurality of DMX devices 6A to 6F (hereinafter, simply referred to as “DMX devices 6”).

In this light control system, the DMX device operation devices 1A and 1B and the network connection device 2A
The DMX signal line 11 conforms to the X512 standard, and the network connection device 2B and the DMX device 6
They are connected by X signal lines 12.

The DMX device operation device 1 includes an operation unit such as a fader or a switch, and generates dimming control data indicating the dimming control content of each DMX device 6 when the operation unit is operated by a user. Also, the DMX device operating device 1
Has a DMX communication unit, and transmits the dimming control data to the network connection device 2 via the DMX signal line 11 in a signal form and a communication method according to the DMX512 standard by the DMX communication unit.

As a result, the DMX device operating device 1
It transmits 512-byte data to the network connection device 2 every 4 msec.

The network connection device 2A is connected to the DMX device operation device 1 and the LAN network 5, and
It receives 512 bytes of dimming control data from the X device operating device 1 every 24 msec. Network connection device 2
A transmits the received dimming control data to the LAN network 5
Then, the packet is converted into a packet for transmission and output to the LAN network 5.

The network connection device 2B is connected to the LAN network 5 and the DMX device 6, and receives a packet including dimming control data via the LAN network 5. The network connection device 2B extracts the dimming control data from the received packet and outputs it to the DMX device 6 according to the DMX512 standard.

When both the network connection devices 2A and 2B receive the dimming control data according to the DMX512 standard, the network connection device 2A and the network connection device 2B send the data to the LAN network 5 as a packet according to the LAN standard.
When a packet conforming to the AN standard is received, a process of converting the packet into dimming control data conforming to the DMX512 standard and outputting it to the DMX device 6 can be performed. That is, the network connection device 2A and the network connection device 2B have the same function.

The switching device 3 is provided with a UDP (User
Datagram Protocol) or TCP (Transmission Contr)
ol Protocol), IP (Internet Protocol), and LAN standards, and relays the received packet to a predetermined communication path.

The DMX device 6 is composed of a lighting device, receives the dimming control data according to the DMX512 standard from the network connection device 2B, and, among the data indicating the dimming control contents of all the DMX devices 6, its own data. It operates according to the dimming control data of the part. Specifically, the DMX device 6
On / off switching, brightness adjustment, illumination direction adjustment, and the like are performed according to the dimming control data. The DMX device 6
It receives the dimming control data and transfers the dimming control data to the adjacent DMX device 6.

In this example, dimming control data in accordance with the DMX512 standard from the DMX device operating device 1A is received by the network connection device 2A via the DMX signal line 11, and is transmitted to the network via the switching device 3 and the LAN network 5. The dimming control data is transmitted to the connection device 2B, and the DMX devices 6A to 6D are transmitted from the network connection device 2B.
A case where dimming control data is transmitted to F via the DMX signal line 12 will be described. Therefore, in the following description, the network connection device 2A is referred to as a “transmission-side network connection device”, and the network connection device 2B is referred to as a “reception-side network connection device”.

[Structure of Transmission-Side Network Connection Device] FIG. 2 shows the structure of the transmission-side network connection device. The transmitting-side network connecting device and the receiving-side network connecting device have the same function, and the description of the transmitting-side network connecting device will be described below, and the description of the receiving-side network connecting device will be omitted.

The transmitting-side network connection device includes a DMX communication unit 21 connected to the DMX signal line 11, a transmitting-side protocol conversion unit 22, and a LAN communication unit 23.

The DMX communication unit 21 operates in accordance with the DMX512 standard, like the DMX device operating device 1, and receives the dimming control data with a predetermined data amount every predetermined period. DM
The X communication unit 21 outputs the received dimming control data to the transmission-side protocol conversion unit 22.

The transmission-side protocol conversion unit 22 is a DMX5
It has a function of converting 12-dimming control data into LAN-standard packets and converting LAN-standard packets into DMX512-dimming control data. Upon receiving the dimming control data from the DMX communication unit 21, the transmission-side protocol conversion unit 22 generates a packet in which LAN standard header information is added to the dimming control data, and
Output to

The LAN communication unit 23 includes a transmission / reception control unit 31 for selecting a data transmission method and transmitting / receiving packets,
A traffic detection unit that acquires network status information indicating the status of the AN network;

The traffic detection unit 32 is provided for the current LAN.
A traffic parameter indicating the state of the network 5 is obtained. The traffic detection unit 32 performs LAN network 5 based on the acquired traffic parameters.
By measuring the traffic volume at the time, traffic state information indicating the traffic congestion status within a predetermined time is generated. The traffic detection unit 32 outputs the generated traffic state information to the transmission / reception control unit 31.

As a method of acquiring traffic parameters by the traffic detector 32, a collision counter for receiving a collision detection signal transmitted in response to occurrence of a collision in the switching device 3 is provided inside the traffic detector 32. The counter value from the collision counter is acquired as a traffic parameter every predetermined period. Then, the traffic detection unit 32 compares the counter values of the collision counters that are temporally different from each other, and sets the increase amount as traffic state information. The collision counter counts the number of times that a collision detection signal transmitted due to occurrence of a packet collision in the switching device 3 is received, and the counted value is generated as a counter value.

As another method of acquiring the traffic parameters by the traffic detecting section 32, a counter value from a traffic counter provided in the receiving-side network connection device at the data transmission destination is received at predetermined intervals, and The obtained counter value is obtained as a traffic counter. Then, the traffic detection unit 32
The counter values of the traffic counters before and after in time are compared, and the increase amount is used as traffic state information. This traffic counter counts according to the amount of received packets and generates the counted value as a counter value. When the counter value of this traffic counter is used as a traffic parameter, the transmitting side network connecting device and the receiving side network connecting device are, for example, SNMP.
(Simple Network Management Protocol) and other device management protocols.
IB (Management Information Base) or the like is used.

The transmission / reception control unit 31 has a function of transmitting / receiving data according to a plurality of data transmission methods, and selects an optimum data transmission method from among the plurality of data transmission methods based on the traffic state information from the traffic detection unit 32. A packet is transmitted from the transmission-side protocol converter 22 to the LAN network 5 according to the selected data transmission method.

In a normal state where congestion of the LAN network 5 does not occur, the transmission / reception control unit 31 sends a packet to the receiving-side network connection device in a half-duplex manner in accordance with UDP / IP in order to give the highest priority to the communication speed. Send In a normal state, the transmission / reception control unit 31 packetizes dimming control data input every 24 msec and transmits the packet every 24 msec.

When the transmission / reception control unit 31 determines that the traffic volume of the LAN network 5 is large based on the traffic status information, the transmission / reception control unit 31 transmits the packet according to TCP / IP in order to prevent the packet from being lost in the LAN network 5. Select a data transmission method. At this time, the transmission / reception control unit 31 performs a process of establishing a connection with the transmission / reception control unit 31 of the receiving-side network connection device for performing delivery confirmation and retransmission control according to TCP.

Further, the transmission / reception control unit 31 is provided with a TCP / IP
When a packet is transmitted using a data transmission method that conforms to the rules above, it is determined that the traffic volume is very large by performing retransmission control by colliding the transmitted packet with the received packet by processing such as delivery confirmation and retransmission control. When you do
Select a data transmission method for transmitting packets by full-duplex method. At this time, only the transmission / reception control unit 31 of the transmission-side network connection device may transmit / receive packets in full-duplex mode, and the transmission / reception control unit 31 of the reception-side network connection device also transmits / receives packets in full-duplex mode. May be.

Further, the transmission / reception control unit 31 is provided with a TCP / IP
Alternatively, a full-duplex method may be selected even when a packet is transmitted using UDP / IP.

[Other Configuration of Transmission-Side Network Connection Device] FIG. 3 shows another configuration of the transmission-side network connection device. This transmission-side network connection device differs from the transmission-side network connection device shown in FIG. 2 in that a data content determination unit 41 is provided in the transmission / reception control unit 31.

The data content discriminating section 41 discriminates the data content of the dimming control data input from the transmitting side protocol converting section 22, and generates a discrimination result.

The transmission / reception control section 31 includes a data content determination section 4
If the data content of the dimming control data to be transmitted this time is different from the data content of the previously transmitted dimming control data based on the determination result of 1, the dimming control data to be transmitted is A process is performed in which header information is added and transmitted.

On the other hand, based on the determination result of the data content determination unit 41, the transmission / reception control unit 31 replaces the data content of the dimming control data to be transmitted this time with the data content of the previously transmitted dimming control data. If it is the same as, the data is deleted without performing the transmission process.

The transmission / reception control section 31 reliably transmits the packet to the receiving-side network connection device only when the packet is transmitted only when the data content of the dimming control data that is temporally different is different. TCP / I for
The packet may be transmitted according to P.

Further, based on the traffic state information from the traffic detection unit 32, the transmission / reception control unit 31 transmits a packet only when the data content of the dimming control data that is temporally different is different when the traffic volume is large. When the processing is performed and the traffic volume is small, all the dimming control data input from the transmitting-side protocol converter 22 may be transmitted.

The transmitting-side network connection device may, of course, have the function described with reference to FIG. 2 for selecting a data transmission method based on the traffic amount.

[Data Transmission Process of Transmission-Side Network Connection Device] FIG. 4 shows a processing procedure when the transmission-side network connection device transmits a packet including dimming control data to the reception-side network connection device. In the following description of the process of transmitting a packet by the transmission-side network connection device, the function of selecting a data transmission method based on the traffic volume and the case where the data content of the dimming control data that is temporally different are different. This is an example of processing by a transmitting-side network connection device having both functions of transmitting only a packet.

The transmitting-side network connection device starts the process of step S 1 in response to the dimming control data being transmitted from the DMX device operating device 1.

In step S 1, dimming control data from the DMX device operating device 1 is received by the DMX communication unit 21. Here, the dimming control data is transmitted in 512 bytes every 24 msec. In step S1, the dimming control data received by the transmitting-side protocol converter 22 is converted into a LAN standard packet by performing protocol conversion.

In the next step S2, the traffic parameters are acquired by the traffic detector 32,
The traffic state information based on the traffic parameters is generated and output to the transmission / reception control unit 31. The transmission / reception control unit 31 determines whether the traffic volume of the LAN network 5 is large. When the transmission / reception control unit 31 determines that the traffic volume is large, the process proceeds to step S4. When the transmission / reception control unit 31 determines that the traffic volume is small, the process proceeds to step S3.

In step S3, since it is determined in step S2 that the traffic volume is small, the transmission / reception control unit 31 transmits a packet using UDP / IP in a half-duplex system which is a normal data transmission system. To end.

In step S4, it is determined whether the data content of the dimming control data included in the previously transmitted packet is the same as the data content of the dimming control data included in the packet currently being transmitted. The transmission / reception control unit 31 determines whether or not it is not. If the transmission / reception control unit 31 determines that the data contents are the same, step S6
Then, the processing is terminated without transmitting the packet to be currently transmitted. On the other hand, if the transmission / reception control unit 31 determines that the data contents are not the same, the process proceeds to step S5 to convert the data into a packet of the selected data transmission method, transmit the packet, and terminate the process.

As described above, the process of selecting a data transmission method based on the network state information and transmitting the packet, or transmitting the packet only when the data content of the dimming control data that is temporally different is different. All the above-described processing procedures including the processing to be performed may be stored in a recording medium as a computer-readable program.
At this time, the transmitting side network connecting device and the receiving side network connecting device read out the program stored in the recording medium, start and execute the same processing as described above, whereby the same effect can be exhibited.

[Data Reception Processing of Reception-Side Network Connection Device] FIG. 5 shows a processing procedure when the reception-side network connection device receives a packet including dimming control data from the transmission-side network connection device.

The receiving-side network connection device starts the process of step S11 in response to the transmission of the packet including the dimming control data from the transmitting-side network connection device.

In step S11, it is determined whether the LAN communication unit 23 has received a packet from the transmission-side network connection device. When it is determined that the packet has been received by the LAN communication unit 23, step S1 is executed.
The process proceeds to step S2, and if it is determined that no packet has been received by the LAN communication unit 23, the process proceeds to step S13.

In step S12, step S1
1 is converted to DMX512 standard dimming control data by
The X device 6 is reset as transmission data. Before receiving the packet in step S11, the dimming control data included in the previously received packet is set as data to be transmitted.

In step S13, the DMX
From the time when the dimming control data is transmitted to the device 6, the DMX 51
The DMX communication unit 21 determines whether 24 msec, which is the communication interval defined by the two standards, has elapsed.

When it is determined that 24 msec has elapsed, the process proceeds to step S14, and the dimming control data received in step S11 or the dimming control data set before step S11 is transmitted to the DMX device 6 and the processing is performed. To end.

[Effects of Embodiment] As described above in detail, according to the transmission-side network connection device to which the present invention is applied, the traffic detection unit 32 acquires the traffic parameters, and the transmission / reception control unit 31 transmits the traffic parameters. Since the data transmission method can be selected according to the amount, an increase in the amount of traffic in the LAN network 5 can be suppressed.

Further, according to the transmitting-side network connection device, the traffic detection unit 32 can acquire the counter value from the collision counter in the traffic detection unit 32 as a traffic parameter and select a data transmission method. LA to reduce the number of collisions
An increase in traffic of the N network 5 can be suppressed.

Further, according to the transmission-side network connection device, the traffic detection unit 32 can acquire the counter value from the traffic counter of the reception-side network connection device as a traffic parameter and select the data transmission method. The traffic amount to the network connection device can be suppressed, and the traffic amount of the LAN network 5 can be suppressed.

Further, according to the transmitting-side network connection device, a packet can be transmitted only when the dimming control data which is temporally different is different, so that only the necessary dimming control data is transmitted to the receiving-side network connection device. It can be transmitted to the device, and an increase in the traffic volume of the LAN network 5 can be suppressed.

Further, according to the transmission-side network connection device, when the traffic volume is large, the packet is transmitted only when the dimming control data which is temporally different is different,
When the traffic volume is small, all the dimming control data is transmitted, so that an increase in the traffic volume of the LAN network 5 can be suppressed.

Furthermore, according to the transmission-side network connection device, when the traffic volume of the LAN network 5 is large, the packet can be reliably transmitted to the reception-side network connection device by changing from UDP to TCP.

Further, according to the transmission-side network connection device, when a collision between a transmission packet and a reception packet occurs when using TCP, the half-duplex system is switched to the full-duplex system. And reduce the number of times of performing retransmission control by suppressing the occurrence of packet collision.
An increase in the traffic volume of the network 5 can be suppressed.

The above embodiment is an example of the present invention. For this reason, the present invention is not limited to the above-described embodiment, and other than the present embodiment, various modifications may be made according to the design and the like within a range not departing from the technical idea according to the present invention. Can be changed.

[0077]

According to the first aspect of the present invention, a data transmission method for transmitting a packet converted by the data conversion means on the network is selected based on the traffic state, and the packet is transmitted to the network. Therefore, the data transmission processing can be changed according to the traffic volume in the network, and the increase in the network traffic volume can be suppressed.

According to the network connection device of the second aspect, the counter value obtained by the collision counter is obtained as a traffic state, and the data transmission method is selected based on the increment of the counter value by the collision counter. It is possible to suppress an increase in network traffic so as to suppress the number of packet collisions.

According to the network connection device of the third aspect, the counter value from the traffic counter is acquired as the traffic state, and the data transmission method is selected based on the increment of the counter value by the traffic counter. The traffic volume to the network connection device can be suppressed, and the traffic volume of the network can be suppressed.

According to the network connection device of the fourth aspect, the data content of the control data received by the transmission / reception means at the first time differs from the data content of the control data received by the transmission / reception means after the first time. Control data is sent to the network only when it is determined by the data content determining means, that only necessary control data can be sent to the network, and an increase in network traffic can be suppressed.

According to the fifth aspect of the present invention, a connection is established with a network connection destination of a packet transmission destination in accordance with a communication protocol for performing retransmission control of a packet. Can be sent to the device.

According to the network connection apparatus of the sixth aspect, since the transmitting and receiving means performs packet transmission and reception in a full-duplex system, collision between transmitted and received packets is suppressed to reduce the number of retransmissions. An increase in network traffic can be suppressed.

According to the network connection device of the present invention, when the traffic volume is small, all the control data received and converted by the data conversion means are transmitted to the network, so that the network traffic volume when the traffic volume is large. Increase can be suppressed.

According to the network connection method of the present invention, a data transmission system for transmitting the converted packet through the network is selected based on the traffic condition, and the converted packet is transmitted to the network according to the selected data transmission system. , The data transmission processing can be changed according to the traffic volume in the network, and an increase in the network traffic volume can be suppressed.

According to the network connection method of claim 9, when it is determined that the data content of the previously received control data is different from the data content of the control data received this time, the data content is included in the converted packet, Since the control data received this time is transmitted to the network, only necessary control data can be transmitted to the network, and an increase in the traffic volume of the network can be suppressed.

[0086] According to the data transmission program of the present invention, a data transmission system for transmitting a converted packet through a network is selected based on a traffic state, and the converted packet is transmitted to the network according to the selected data transmission system. The data transmission process can be changed according to the traffic volume in the network, and the increase in the traffic volume of the network can be suppressed.

According to the data transmission program of the present invention, when it is determined that the data content of the control data received previously and the data content of the control data received this time are different, it is included in the converted packet, Since the computer transmits the control data received this time to the network, only the necessary control data can be transmitted to the network, and an increase in the traffic volume of the network can be suppressed.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a dimming system.

FIG. 2 is a functional block diagram illustrating a configuration of a transmission-side network connection device to which the present invention has been applied.

FIG. 3 is a functional block diagram showing another configuration of the transmission-side network connection device to which the present invention is applied.

FIG. 4 is a flowchart showing a processing procedure when a packet including dimming control data is transmitted to a receiving network connection device by a transmitting network connection device to which the present invention is applied.

FIG. 5 is a flowchart illustrating a processing procedure when a packet including dimming control data is received by the receiving network connection device.

FIG. 6 is a block diagram illustrating a configuration of a conventional light control system.

FIG. 7 is a block diagram illustrating another configuration of a conventional light control system.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 DMX device operation device 2 Network connection device 3 Switching device 4 LAN device 5 LAN network 6 DMX device 11 DMX signal line 12 DMX signal line 21 DMX communication unit 22 Transmission-side protocol conversion unit 23 LAN communication unit 31 Transmission / reception control unit 32 Traffic detection Section 41 Data Content Discrimination Section

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Osamu Iijima 1048 Kazuma Kadoma, Osaka Pref.Matsushita Electric Works, Ltd. Reference) 5K033 BA08 CA08 CB02 CB03 CC01 5K034 HH01 HH11 HH63 HH64 5K048 BA07 DC07 EA14 EB02 HA01 HA02 HA03

Claims (11)

[Claims] 1. A network connection device connected to a control device for controlling a plurality of load devices and transmitting control data from the control device to a network, wherein the data is transmitted from the control device in a data format according to a control protocol. Transmission / reception means for receiving control data; data conversion means for converting the control data received by the transmission / reception means into packets according to a data transmission protocol transmitted on the network; and traffic state acquisition means for acquiring a traffic state of the network. A transmission method control means for selecting a data transmission method for transmitting a packet converted by the data conversion means on the network based on the traffic state acquired by the traffic state acquisition means; and the transmission method control means. According to the data transmission method selected in Network connection device, characterized in that it comprises a transmission control means for controlling said transmitting and receiving means to the converted packet by the data converting means transmitted to the network Te. 2. A packet relay comprising: a relay unit connected to a plurality of network connection devices for relaying packets from the plurality of network connection devices; and a collision detection unit for detecting packet collision. A collision counter connected to the apparatus via the network, receiving a collision detection signal from the collision detection unit with the transmission / reception unit, and counting the collision detection signal received by the transmission / reception unit; 2. The transmission method control means for acquiring a counter value as a traffic state, wherein the transmission method control means selects a data transmission method based on the increment of the counter value by the collision counter acquired by the traffic state acquisition means. Network connection described Location. 3. The traffic status acquisition means is a destination of a packet transmitted from the transmission / reception means,
It is connected via the network to another network connection device having a traffic counter that counts the amount of data received, and receives a counter value from the traffic counter every predetermined period by the transmission / reception unit,
2. The network according to claim 1, wherein the data is acquired as a traffic state, and the transmission method control means selects a data transmission method based on an increment of a counter value by the traffic counter acquired by the traffic state acquisition means. Connection device. 4. A network connection device connected to a control device for controlling a plurality of load devices and transmitting control data from the control device to a network, wherein the data is transmitted from the control device in a data format according to a control protocol. Transmission / reception means for receiving control data, data conversion means for converting the control data received by the transmission / reception means into a packet according to a data transmission protocol transmitted on the network, and data content of the control data received by the transmission / reception means A data content judging means for judging the data content of the control data received by the transmitting / receiving means at a first time and a data content of the control data received by the transmitting / receiving means after the first time; When determined by the determination means, is included in the packet converted by the data conversion means, Serial network connection device, characterized in that it comprises a transmission control means for controlling data received by the next above transmitting and receiving means of the first time to control the transceiver means to deliver to the network. 5. The network connection device according to claim 4, wherein said transmission / reception means establishes a connection with a network connection device of a packet transmission destination in accordance with a communication protocol for performing packet retransmission control. 6. The network connection device according to claim 4, wherein said transmission / reception means transmits / receives packets by a full-duplex method. 7. A traffic condition acquiring means for acquiring a traffic state of the network, wherein the transmission control means receives the data by the transmitting / receiving means when the traffic amount acquired by the traffic state acquiring means is small. 5. The network connection device according to claim 4, wherein said transmission / reception means is controlled so as to send all control data converted by said conversion means to said network. 8. A data transmission method for transmitting control data from a control device controlling a plurality of load devices to a network, comprising: receiving control data transmitted from the control device in a data format according to a control protocol; When transmitting the control data to the destination network connection device, the traffic status of the network is obtained, and the received control data is converted into a packet according to a data transmission protocol transmitted on the network, and the obtained control data is obtained. A data transmission method, comprising: selecting a data transmission method for transmitting a converted packet through the network based on the traffic state, and transmitting the packet converted according to the selected data transmission method to the network. 9. A data transmission method for transmitting control data from a control device for controlling a plurality of load devices to a network, comprising: receiving control data transmitted from the control device in a data format according to a control protocol; When transmitting the control data to the destination network connection device, the data content of the received control data is determined, and the received control data is converted into a packet according to a data transmission protocol transmitted on the network. Transmitting the control data included in the converted packet to the network when the data content of the previously received control data is different from the data content of the control data received this time. Data transmission method. 10. A data transmission program for executing a data transmission method for transmitting control data from a control device for controlling a plurality of load devices to a network, the control data being transmitted from the control device in a data format according to a control protocol. Receiving the control data and transmitting the control data to the destination network connection device, in accordance with a data transmission protocol for acquiring the traffic state of the network and transmitting the received control data over the network. A process of converting a packet into a packet, selecting a data transmission method for transmitting the converted packet on the network based on the obtained traffic state, and transmitting the packet converted according to the selected data transmission method to the network. To make a computer run Data transmission program and butterflies. 11. A data transmission program for executing a data transmission method for transmitting control data from a control device for controlling a plurality of load devices to a network, the control data being transmitted from the control device in a data format according to a control protocol. A data transmission protocol for receiving the control data received, transmitting the control data to a destination network connection device, determining the data content of the received control data, and transmitting the received control data over the network. And if the data content of the previously received control data is different from the data content of the control data received this time, the control packet included in the converted packet and the control data received this time A computer characterized by causing a computer to execute the processing for transmitting to the network. Data transmission program.