JPH04282933A - Data transmission system - Google Patents

Abstract

PURPOSE:To expand a transmission system inexpensively in a short time by providing an address to identify a communication system and an identifier to identify a transmission direction of a data into a data packet when link communication systems are interconnected. CONSTITUTION:An address to identify a communication system and an identifier to identify a transmission direction of a data are provided to a data packet. Then a transmission exclusive station and a reception exclusive station are inserted to the link communication system in which the data frame is added and linked and the stations are interconnected. The reception exclusive station discriminates whether or not the data frame is aborted by using an address in the data frame to be received and decides the transmission direction to a ring by using the identifier. Thus, a node station on data transmission systems X, Y, Z makes data exchange through a link data line. Then the transmission exclusive station and the reception exclusive station are interconnected between node stations with a shortest distance to decrease the extension period of the data line and to reduce the cost.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to data communication control means for expanding ring-type communication systems by interconnecting them through data transmission lines.

0002

2. Description of the Related Art FIG. 4 shows a case where a modified ring type transmission system is newly installed by connecting existing ring type transmission systems. One ring type data transmission system When installing a new deformed ring system W,
Between AX and EX, between CX and DX, AY and BY
Construction work to remove cables in both clockwise and counterclockwise directions between AZ and BZ, and AX
This required work to add cables in both directions between AY and AY, between EX and BY, between CX and BZ, and between DX and AZ.

0003

[Problems to be Solved by the Invention] In the conventional example, in order to connect ring-type data transmission systems to create an expanded ring-type data transmission system, the conventional cables were removed and the overall configuration was significantly changed. It needed to be changed. Generally, each node station in a ring type data transmission system is installed at a geographically distant location, so changing the ring type configuration poses problems in terms of cost, construction methods, and the period required to install the equipment.

SUMMARY OF THE INVENTION The present invention aims to eliminate such drawbacks and provides a data transmission system having means for simplifying the interconnection of link communication systems.

[0005]

[Means for Solving the Problems] The present invention includes a plurality of link communication systems including a plurality of node stations connected in a ring shape by a clockwise first line and a counterclockwise second line, Each of these node stations includes a first receiving means for receiving a data frame from an adjacent station in the communication system to which the node station belongs, and an additional means for adding a data frame sent from the own station to the data frame received by the first receiving means. and a first transmitting means for selecting either the first line or the second line based on the direction identifier added to the data frame passing through the adding means and transmitting the selected line to an adjacent station in the communication system to which the own station belongs. In a data transmission system in which one of the link communication systems and another link communication system are connected by a third line, each of the first transmission means of the node station transmits a data frame transmitted from the own station. One of the node stations connected to the third line is equipped with means for adding an address indicating the destination link communication system within the data frame, and one of the node stations connected to the third line adds an address in a clockwise or counterclockwise direction to the data frame passing through the adding means. and a data frame transmitting means that is a second transmitting means for transmitting a data frame passing through the identifier adding means via the third line, The other connected node station has second receiving means that receives the data frame via the third line, and the own station determines the address added in the data frame received by the second receiving means. A data frame deletion means deletes the data frame when it is determined that the data frame has been sent by the communication system to which it belongs, and a direction identifier added to the data frame that has passed through this data frame deletion means is stored in the above-mentioned The present invention is characterized by comprising an identifier deletion means for instructing one transmission means and providing the first transmission means with a data frame from which the direction identifier has been deleted.

[0006]

[Operation] An address that identifies each link communication system and an identifier that identifies the data transmission direction are added to the data frame in the data packet, and a transmission-only station and a reception-only station are inserted in each of the link communication systems to be combined. and connect these stations. The receive-only station determines whether to discard the received data frame based on the address in the data frame, and
The identifier also determines the transmission direction to the link.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a data transmission system based on this method, and shows the basic configuration of a data transmission system in which a variable ring transmission system W is newly installed to which existing ring transmission systems X, Y, and Z are connected. Also AX ~ EX, AY ~ EY, AZ
~EZ are node stations of the ring type transmission system. And 1X, 1Y, 1Z are clockwise data lines, 2X
, 2Y, 2Z are counterclockwise data lines, and the direction of data transmission is indicated by an arrow. 3 is a data line connecting node stations EX and BY, 4 is a data line connecting node stations CY and AZ, and 5 is a data line connecting node stations BZ and DX. FIG. 2 is a block diagram showing the configuration of a node station.

That is, in this embodiment, FIGS. 1 and 2
As shown in the figure, data line 1, which is the first line in the clockwise direction,
Node stations AX, BX, CX, DX, EX connected in a ring with X, 1Y, 1Z and counterclockwise second data lines 2X, 2Y, 2Z.
, AY , BY , CY , DY , EY , AZ
, BZ , CZ , DZ , EZ , and the node stations AX , BX , CX
, DX , EX , AY , BY , CY , DY
, EY, AZ, BZ, CZ, DZ, and EZ are data frame receiving means 11, which is a first receiving means for receiving data frames from adjacent stations in the communication system to which the own station belongs, and data received by this receiving means. The own station data frame adding means 12, which is an adding means for adding a data frame sent from the own station to the frame, and the direction identifier added to the data frame passing through this adding means, the first line or the second line. It is equipped with a data frame transmitting means 13 which is a first transmitting means for selecting one of them and transmitting it to an adjacent station of the communication system to which the own station belongs, and one of the link communication systems X, Y and Z and the other link communication system. The nodes are connected by data lines 3, 4, and 5, which are third lines, and the node stations AX, BX, CX, DX, EX, AY
, BY , CY , DY , EY , AZ , BZ ,
Each of the first transmission means of CZ, DZ, and EZ is
The node stations EX, CY, and BZ connected to the third line are equipped with means for adding an address indicating the destination link communication system to the data frame sent from the own station, and the node stations EX, CY, and BZ connected to the third line pass through the adding means. an identifier adding means 14 for adding a direction identifier for identifying a clockwise direction or a counterclockwise direction to a data frame; and a second transmitting means for transmitting the data frame passing through the identifier adding means 14 via the third line. The other node stations BY, AZ, and DX, which are equipped with a data frame transmitting means 15 and connected to the third line, are second receiving means that receive data frames via the third line. The receiving means 16 judges the address added in the data frame received by this second receiving means and deletes this data frame when it is judged that the data frame is sent by the communication system to which the own station belongs. The data frame deletion means 17 and the direction identifier added to the data frame that has passed through the data frame deletion means 17 are instructed to the first transmission means of the local station, and the data frame from which this direction identifier has been deleted is transmitted to the first transmission means. It is provided with an identifier deletion means 18 for giving an identifier.

Next, the operation of this embodiment will be explained. In the data transmission system according to the present invention, the node station EX on the existing ring data transmission system
Z-system and X-system data packets are transferred to node BY via data line 3. The EX station performs through transfer of data packets received by the E station to the ring data transmission system Y. The BY station finds a data packet of its own system, the Y system, among the data packets received from the EX station, and discards the data. Also, the BY station is only for receiving from other stations. Then, after the data packets of the Z system and the X system, a data packet of the local station is attached and transmitted to the AY station via the clockwise data line and to the CY station via the counterclockwise data line. Similarly, the existing ring data transmission system Y
The upper node station CY sends the data packets of the Z system,
Transfer to. The CY station performs through transfer of data packets received by the CY station to the ring data transmission system Z. The AZ station finds a data packet of its own station, the Z system, among the data packets received from the CY station, and discards the data. Also, AZ stations are only for receiving from other stations. Then, after the X-system and Y-system data packets, the local station data packet is attached and sent to the EZ station via the clockwise data line, and to the B station via the counterclockwise data line.
Transmit to station Z. Similarly, the node station BZ on the existing ring data transmission system Z transfers the X-system, Y-system, and Z-system data packets received thereto to the node station D via the data line 5. The BZ station performs through transfer of data packets received by the BZ station to the ring data transmission system X. The DX station finds a data packet of its own system, the X system, among the data packets received by the BZ station, and discards the data. Also, the DX station is only for receiving from other stations. Then, after the data packets for the X and Y systems, a data packet for the local station is attached and transmitted to the CX station via the clockwise data line and to the EX station via the counterclockwise data line.

[0010] In this way, there is a dedicated station that unconditionally transmits data packets from its own system and other station systems received at its own station to node stations of other data transmission systems, and a dedicated station that transmits data packets from these other station systems to node stations of other data transmission systems. A dedicated station will be set up for reception. The data packets between these dedicated stations are received by each node station with an identifier added to identify from which direction the data packet was received from the lines 1X, 2Y or 1Z, 2Z of the ring data transmission system. The data is transferred to the dedicated station, and the node station that receives it recognizes this identifier and sends it out in either direction of its own data transmission system. Also, at this time, the identifier is removed and transmitted. Then, in order to determine the data transmission system, the data packet has an address for identifying each system, and the node station determines which system should be transferred. In order to determine the data transmission system, the data packet has an address to identify each system, and the receive-only station selects its own address from among the received data packets in order to add the latest data packet. Discard the data packet. By connecting these reception and transmission dedicated stations to the node stations with the shortest distance in each data transmission system, it is possible to save the time and cost of adding data lines. As a result, each node station on data transmission systems X, Y, and Z exchanges data through both ring data lines, and the entire data transmission system operates as one ring-type data transmission system.

[0011]

Effects of the Invention As explained above, the present invention enables cables to be connected between a transmission-only station and a reception-only station when connecting a ring-type data transmission system to another existing ring-type data transmission system. Since it is only necessary to add more units, the ring type data transmission system can be expanded at low cost and in a short period of time.

[Brief explanation of the drawing]

FIG. 1 is a block configuration diagram showing the overall configuration of an embodiment of the present invention.

FIG. 2 is a block configuration diagram showing a partial configuration of an embodiment of the present invention.

FIG. 3 is a block configuration diagram showing a partial configuration of an embodiment of the present invention.

FIG. 4 is a block configuration diagram showing the overall configuration of a conventional example.

[Explanation of symbols]

1X, 1Y, 1Z, 2X, 2Y, 2Z, 3,
4 and 5 Data line 11 Data frame receiving means 12
Local station data frame addition means 13 Data frame transmission means 14 Identifier addition means 15 Data frame transmission means 16
Data frame receiving means 17 Data frame deleting means 18 Identifier deleting means AX, BX, CX, DX, EX, AY, B
Y, CY, DY, EY, AZ, BZ, CZ, DZ and EZ Node stations X, Y
and Z link communication system

Claims (1)

[Claims] Claim 1: A plurality of link communication systems including a plurality of node stations connected in a ring shape by a clockwise first line and a counterclockwise second line, each of the node stations being connected to its own station. a first receiving means for receiving a data frame from an adjacent station in a communication system to which the first receiving means belongs; an adding means for adding a data frame sent from the local station to the data frame received by the first receiving means; and data passing through the adding means. a first transmitting means for selecting either the first line or the second line based on a direction identifier added to the frame and transmitting the selected line to an adjacent station of the communication system to which the own station belongs; In a data transmission system in which one link communication system and another link communication system are connected by a third line, each of the first transmission means of the node station transmits the link communication of the destination in the data frame sent from the own station. One of the node stations connected to the third line, which is equipped with means for adding an address indicating the system, adds a direction identifier for identifying a clockwise direction or a counterclockwise direction to the data frame passing through the addition means. The other node station connected to the third line comprises an identifier adding means and a data frame transmitting means which is a second transmitting means for transmitting the data frame via the identifier adding means via the third line. , a second receiving means for receiving a data frame via the third line; a data frame sent by the communication system to which the own station belongs after determining the address added in the data frame received by the second receiving means; When it is determined that the data frame is a A data transmission system characterized by comprising an identifier deletion means for providing a data frame from which a direction identifier has been deleted to the first transmission means.