JPH03187545A - Transmission control system - Google Patents

Abstract

PURPOSE:To improve efficiency for utilizing a transmission line by transmitting a signal only to the transmission line in the direction of a destination as much as possible and preventing the signal from being transmitted to the transmission line in the opposite direction when the signal is transmitted from a communication equipment onto the transmission line. CONSTITUTION:A communication equipment Z is a bidirectional transceiver, which can execute transmission and reception, connected in the state of being inserted to the transmission line and a change-over switch, D switches the transmission of the signal between transmission lines A and B and an equipment J connected to the communication equipment Z. Then, a control circuit 1 changes over the switch D by storing the address and direction of the transmitting destination while making them correspondent. When the signal is transmitted from the communication equipment Z onto the transmission line, the constitution is adopted so that the signal can be transmitted only to the transmission line in the direction of the destination as much as possible and can not be transmitted to the transmission line in the opposite direction. Thus, the efficiency can be improved for utilizing the transmission line.

Description

[Detailed Description of the Invention] [Summary] Regarding a transmission control method for a communication device connected in a manner that it is inserted into a bidirectional transmission path, when transmitting a signal from the communication device onto the transmission path, only the transmission path in the destination direction is used. The communication device Z is connected in such a way that it is inserted into a bidirectional transmission path, with the aim of improving the utilization efficiency of the transmission path by transmitting signals as much as possible and not transmitting signals to the transmission path in the opposite direction. Then, within this communication device Z, a switch that switches the transmission of signals between transmission path A, transmission path B, and device J connected to the communication device Z is associated with the address and direction of the transmission destination. The communication device Z is equipped with a wI control circuit that memorizes and switches this switch.
When transmitting a signal from device J connected to , the control circuit I transmits the signal only to transmission path A or transmission path B in the stored direction when it corresponds to the destination address stored. On the other hand, when this is not applicable, the switch is switched so that the signal is transmitted in both directions of transmission path A and transmission path B, and furthermore, the direction when a response signal is received is changed. The switching device is configured to switch so that the signal is transmitted only to transmission path A or transmission path aB.

[Industrial application field]

The present invention relates to a transmission control method for a communication device connected in a vA manner and inserted into a bidirectional transmission path. Computer systems are becoming increasingly networked year by year. Along with this, the amount of traffic on the network (transmission path) is also increasing, so it is desired to improve the efficiency of the network in order to perform good communication.

[Prior Art] Conventionally, there is a type of network system in which a communication device (for example, a transceiver) is connected by a type B inserted into a transmission path. In this network system, when a signal (for example, a frame) is transmitted from a node side (device side) to a transmission path via a communication device, the signal is equally transmitted to the transmission path on both sides when viewed from the communication device. Then, the communication device of the corresponding destination receives this signal from the transmission path, while the communication device of the other destination transmits this signal to the transmission path in the opposite direction.

[Problem to be solved by the invention]

Therefore, even if it is known in which direction the node with the target address (destination) is located as seen from the communication device, the signal is transmitted equally to both transmission paths and the target address is transmitted. There is a problem in that the transmission path that is not in the direction of the node being owned becomes unusable, which reduces the efficiency of using the transmission path.

The present invention utilizes the transmission path by transmitting the signal only to the transmission path in the destination direction as much as possible when transmitting the signal from the communication device onto the transmission path, and not transmitting the signal to the transmission path in the opposite direction. The purpose is to improve efficiency.

(Means to solve !IN) FIG. 1 shows a block diagram of the principle of the present invention.

In FIG. 1, a communication device 2 is a bidirectional transceiver that is inserted into a transmission path and connected in an S-like manner and capable of transmitting and receiving.

The switching device is for transmission line A5, transmission line B, and communication VT location Z.
This is a switch that switches the transmission of signals between the device J and the device J connected to the device J.

The control circuit 1 stores and switches the transmission destination address (DA) and direction in association with each other! This is a circuit that switches the ID.

[Effect]

As shown in FIG. 1, the present invention connects a communication device NZ by inserting it into a bidirectional transmission path, and within this communication device Z, connects it to a transmission path A, a transmission path B, and the communication device 2. The communication device 2 is equipped with a switching device for switching the transmission of a signal between the device
When transmitting a signal from device J connected to control circuit l
When the address of the transmission destination corresponds to the stored destination address, the switch is switched so that the signal is transmitted only to the stored direction of transmission path A or transmission path B. On the other hand, when it does not correspond to the transmission path A and switch the switch so that the signal is transmitted in both directions of transmission path B, and further switch the switch so that the signal is transmitted only to transmission path A or transmission path B in the direction when the response signal is received. I'm trying to switch it up.

Therefore, when transmitting a signal from a communication device onto a transmission path, the efficiency of using the transmission path can be improved by transmitting the signal only to the transmission path in the destination direction and not transmitting the signal to the transmission path in the opposite direction. It becomes possible to improve the performance.

(Embodiment) Next, the configuration and operation of an embodiment of the present invention will be sequentially explained in detail using FIGS. 1 to 3.

In FIG. 1, a communication device Z is a bidirectional transceiver that is capable of transmitting and receiving data and is connected to bidirectional transmission paths A and B that constitute a network (for example, a LAN transmission path).

The signal line C is connected to a transmission line A, a transmission line B via a switching device,
This is a signal line that connects to the signal conversion circuit H.

The switching station has the function of switching the transmission of signals between the transmission path A, the transmission path B, and the device J connected to the communication device 2, and also has the function of switching the transmission of signals between the transmission path A and the transmission path B. It has a function of determining the transmission direction of the signal and notifying the control circuit (2) of the direction via the control line F.

Signal IIB is a signal line that interconnects device J, signal conversion circuit H, and control circuit (2).

Control'rIJwAF is used to switch and control the switching device,
These stripes are used to determine the direction of signal transmission from the switch.

The signal conversion circuit H is for transmission! Converts the standard of the signals flowing on A and B and the standard of the signal required by device J (
This is a circuit that performs voltage level conversion, serial-parallel conversion, etc.

The control circuit τ determines the address (DA) of the signal (packet 7, frame) passing through the signal line E, and controls the switching of the connection state of the switch.

A device J is a device connected to transmission path A and transmission path B via communication device Z.

Next, the configuration and operation will be explained in detail using FIG. 2, which is a structural diagram of one embodiment of the present invention.

Figure 2 (a) shows an example of a network, which is
An example of a network in which transceivers 21 to Z4, which are communication devices Z, are inserted between end A1 and end @B of N transmission path as shown in the figure, and devices J, K, L, and M are connected to these, respectively. shows.

FIG. 2 (b) shows an example of the configuration of one communication device z (transceiver), where transmission path A, transmission path B, signal & I
C1 switch, signal line E, control line F, signal conversion circuit 11
, control circuit 1% equipment J correspond to each of those shown in FIG. In addition, the switching device is connected to the transmission line B, to the transmission line B,
It is comprised of a switch that switches the connection between signal lines C, a direction determination section that determines the transmission direction of the signal notified from transmission path A and transmission path B, and the like. The control circuit I receives the address (D
A storage unit that associates A) with its direction and stores it in a manner of learning, and from signal gE to transmission path A and transmission path B.
It is composed of a determination section that determines the direction of the address (DA) of the signal to be transmitted by referring to information stored in the storage section.

Next, the operation of the configuration shown in FIG. 2(b) will be explained using the flowchart of FIG.

In Figure 3, ■ is the address issued by device J (DA
) and the address (DA) held by the control circuit l. This means that, as shown in the upper right corner, in FIG. Address of frame (signal) sent to E (DA, destination node address)
It is determined whether or not the address (DA) stored in the storage section of the control circuit 1 in a learning manner matches or not. If YES, the address (DA) of transmission path A and transmission path B is set to 0.
The signal is transmitted only in the direction of DA). In case of NO,
Do [phase].

Since it is determined that O matches with ■, the switch is switched according to the direction of the control circuit I, and the signal is transmitted. In this case, the address (DA) of the transmission destination to which the signal was transmitted in the past and the transmission direction are stored in the storage unit of the control circuit I as a pair, and the address (DA) from the device j. If the address (DA) of the signal (bakeft) to be transmitted via the signal wAE matches, the direction in which it should be transmitted is known, so the signal is transmitted only in this known direction and not in the opposite direction. Transmit the signal by switching the switch. As a result, transmission path A in the direction in which no signal is transmitted or transmission path is
fZ can be used, and the transmission path can be used effectively.

0 determines whether it is the end of signal transmission. If YES, both transmission lines (transmission aA
,transmission! B) remains connected.

If No, repeat ◎ until the transmission is completed.

[Phase] is determined not to match in ■, so the switching device maintains both transmission lines in the connected state as usual. As a result, the signal from device J is transmitted to both transmission path A and transmission path B via the switching device, as in normal operation. Then, when transmitting the signal after receiving the response from the destination communication device Z, the switching device is switched so that the signal is transmitted only in the direction in which it was received,
transmit signals.

Next, switching of the transmission line A, transmission jlaB, and signal line C will be specifically explained. Here, in the switching device,
It is assumed that transmission path A, transmission path B1, and signal line C (equipment J) are all connected.

(1) When a signal addressed to the node address of device J flows from transmission path A to communication device Z, this signal is transferred to transmission path A-
The switching device transmits the signal MC to the signal conversion circuit H to the signal line E to the equipment J and the control circuit (2). Control circuit! determines that this signal is addressed to the address of device J, and connects transmission line A and signal line C to the switch via control line F while this signal is flowing, and connects transmission line A and signal line C to transmission line B. is controlled so that it is disconnected from this connection, and the signal from transmission line A is controlled so as not to flow to transmission line B. Then, when the signal destined for device J ends, transmission path A, which is in the original connection state,
All three of the transmission line B, signal & IC are controlled to be connected. As a result, when the signal flows to device J via transmission path A, it becomes possible to cut off transmission path B and use the transmission path B for other transmissions.

(Illusion) Also, if a signal addressed to the node address of device J flows from transmission path B to communication device Z, it is possible to similarly disconnect the transmission path and use the transmission path A for other transmissions. becomes.

(3) When transmitting a signal from device J to a transmission path, the direction in which it was previously sent to device J with that node address (either the direction of transmission path A or transmission path B) is 1M1!1 circuit. If it is stored in the storage section of i, the control circuit I controls the switching device to connect only the transmission path A or transmission 'IRB in the direction in which it is stored, transmit the signal, and switch the other transmission path. Cutting off route B or transmission route A,
This makes it possible to use the separated transmission line B or transmission line A for other transmissions. In addition, if the storage unit does not store the transmission direction, the signal is transmitted toward both transmission path A and transmission path B, and the response signal from the node that received the signal is sent to either transmission path ( It is determined whether the signal is received from transmission path A1 or transmission path B), and only this direction is connected, and the other direction is disconnected. In this way, when transmitting a signal from equipment J to a certain destination, if the transmission path in the direction of the destination is known, the signal is transmitted only to the transmission path in the determined direction; on the other hand, if it is not known, By first transmitting a signal to the transmission path in both directions, and then transmitting the signal only to the transmission path in the direction in which the response signal was received, it is possible to stop transmitting the signal to the transmission path in an unnecessary direction, and transmit the signal. This makes it possible to use roads efficiently.

(4) Next, a specific example will be explained using FIG. 2(a). Here, four communication devices 21 to 24 are connected to the LAN transmission path, and terminal i resistances of terminal A5 and terminal B are connected to the terminal ends of each of them. In this state, according to the present embodiment, for example, communication between the device J and the device 2 and communication between the device 2 and the device M can be performed simultaneously. This separates the communication device Z2 and the communication device z3, and allows the device J to communicate with the device via the path from device J to communication device installation 1 to transmission path to communication device z2 to the device, and at the same time allows the device to communicate with the device. The devices can be coupled by communicating with each other through the path of one communication device z3-transmission path-communication device 24-device M.

〔Effect of the invention〕

As explained above, according to the present invention, when transmitting a signal from a sending device onto a transmission path, the signal is transmitted as much as possible only to the transmission path in the direction of the destination, and the signal is transmitted to the transmission path in the opposite direction. Since a configuration is adopted in which no data is transmitted, it is possible to improve the utilization efficiency of the transmission path. In particular, this makes it possible to reduce signal collisions that conventionally occur on transmission paths and improve network performance.

[Brief explanation of drawings]

FIG. 1 shows the basic configuration of the present invention, FIG. 2 shows the configuration of one embodiment of the present invention, and FIG. 3 shows a flowchart explaining the operation of the present invention. In the figure, A and B are transmission lines, C and E are signal lines, D is a switch,
F represents a control line, H represents a signal conversion circuit, and ■ represents a control circuit. Flowchart explaining the operation of the present invention

Claims (1)

[Claims] In a transmission control method for a communication device connected in a manner inserted into a bidirectional transmission path, a communication device Z is connected in a manner inserted in a bidirectional transmission path, and transmission within this communication device Z is performed. A switch D switches the transmission of signals between path A, transmission path B, and device J connected to the communication device Z, and the address and direction of the transmission destination are stored in association with each other and the switch D is switched. and a control circuit I, when transmitting a signal from equipment J connected to the communication device Z, transmitting in the direction stored when the address of the transmission destination stored in the control circuit I corresponds to the transmission destination address. The above switch D is switched so that the signal is transmitted only to path A or transmission path B. On the other hand, when the signal is not applicable, transmission path A and transmission path B are switched.
The switch D is switched so that the signal is transmitted in both directions, and the switch D is switched so that the signal is transmitted only to the transmission path A or B in the direction when the response signal is received. A transmission control method characterized by being configured as follows.