JP2693799B2 - Data transmission method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Outline] The present invention relates to a data transmission method capable of completing forward and backward transmissions in one round-trip communication frame transmitted from a node that has acquired a transmission right. Speeding up round-trip communication between nodes,
For the purpose of improving efficiency, when one of a plurality of nodes acquires a transmission right via a transmission path and transmits / receives data to / from another node (hereinafter referred to as a receiving node) , The frame received from the node that has acquired the transmission right (hereinafter referred to as the sending node) to the receiving node with the replica data transmission request information inserted and transmitted, and the receiving node receiving the frame in response to the replica data transmission request information. The data is inserted into and the frame is transmitted to the transmitting node.

[Industrial applications]

TECHNICAL FIELD The present invention relates to a data transmission method capable of completing forward and backward communications in one round of a round-trip communication frame transmitted from a node that has acquired a transmission right.

In recent years, local area networks (LANs) that connect distributed computers are rapidly spreading, and their importance is increasing. There are various data transmission methods between two network nodes in the LAN. In order to use the physical level of the LAN and the media access control (MAC) level efficiently to achieve high-speed data transmission, the speed of the LAN transmission line (higher physical level) and the study of media access control are considered. (Higher performance at the MAC level) is being implemented.

[Conventional technology]

A token ring network is one of conventional systems for transmitting data between network nodes. In the data transmission method in this token ring network, after the control advances to the MAC level, which is the level at which data can be transmitted and received in the token ring network, the token that the network node that has the transmission request goes around the token ring. , The transmission right is acquired, and the transmission node becomes a transmission node, and the transmission node transmits the outgoing communication frame onto the token ring (5th
(See figure). Each node on the token ring located on the downstream side of the transmitting node transmits the frame received from the upstream to the downstream.

The receiving node (return path transmitting node in FIG. 5) in that node, while relaying the outgoing message frame, fetches a copy of the outgoing message frame into the buffer in its own node and receives the outgoing message frame (FIG. 5). See).

In this way, the outgoing frame that has reached the transmitting node after making a round of the token ring is removed from the token ring (see FIG. 5). Then, the token is transmitted from the transmitting node to the token ring and the transmission right acquired by the transmitting node is released.

[Problems to be solved by the invention]

According to this conventional method, as shown in FIG. 5, when data is transmitted from one network node to another network node between two network nodes, the outgoing message frame sent from the outgoing node is set to the outgoing node (reception node). ) Is taken in by the return node when it is relayed. Then, when it returns to the forward transmission node, it is removed from the token ring.

This relationship is exactly the same for the return frame (see, and in FIG. 5).

Therefore, when transmitting / receiving data between any two nodes on the token ring, it is necessary to acquire the transmission right for each node. In addition to this, the token ring of the frame is used for transmitting data from the outgoing path sending node to the outgoing path sending (receiving node) and for sending the data from the outgoing path sending node to the outgoing path sending node (receiving node). It takes a round trip through the reverse path transmission node to waste the outgoing frame transmission time from the outgoing path transmission node to the outgoing path transmission node and the outgoing path transmission node to the incoming path transmission node from the outgoing path transmission node. Communication time is long and network traffic is becoming complicated. Therefore, the speed and efficiency of the round trip communication are hindered.

The present invention was created in view of the above problems, and an object of the present invention is to provide a data transmission method capable of increasing the speed and efficiency of round-trip communication between any two nodes in a transmission path. To do.

[Means for solving the problem]

 FIG. 1 shows a principle block diagram of the present invention.

As shown in this figure, the present invention relates to a transmitting node that has acquired a transmission right among a plurality of nodes interposed in a transmission line 10.
From 12, other nodes that want to send data (reception node)
A transmitting means 8 for inserting data to be transmitted to the frame 14 and transmitting the frame, and a receiving node for transmitting the frame via the transmission path 10.
In the data transmission system including the releasing means 7 for releasing the transmission right when the transmitting node returns from 14, when the transmitting node 12 wants to receive the data from the receiving node 14, it is transmitted to the receiving node by the transmitting means 8 of the transmitting node. While the transmitting node 12 is provided with inserting means 9 for inserting the reconstructed data transmission request information into the received frame, the receiving node 14 responding to the response information of the response information section 11 in the received frame, When it is detected that the return data transmission request information is inserted in the return data transmission request information section 13), for example, the required data of the request target of the memory 19 is inserted into the data accommodating section 16 of the frame and the relevant frame is transferred. The receiving node 14 is provided with transmitting means 17 for transmitting to the transmitting node 12.

(Operation)

When it is detected that the receiving node 14 responding to the response information of the frame transmitted from the transmitting node 12 sharing the transmission path 10 has the reconstructed data transmission request information in the frame,
In the data accommodating section 16 of the frame, the transmitting means 17 is connected to the memory 19
The required data in the request target is inserted and transmitted to the transmitting node 12.

Therefore, when data is transmitted and received between the transmitting node and the receiving node, the process of acquiring the transmission right separately for the transmitting node and the receiving node becomes unnecessary, and the data between the transmitting node and the receiving node is not required. The communication time required for sending and receiving is reduced in half and traffic is greatly reduced. As a result, speeding up and efficiency of communication can be obtained.

FIG. 2 shows an embodiment of the present invention. This embodiment relates to data transmission between a primary storage device and a secondary storage device of a computer system. In FIG. 2, reference numeral 20 is a primary storage device. The primary storage device 20 is connected to a network controller 24 via a data bus 22 and also connected to a central processing unit (CPU) not shown. A transmission request line 26 extends from the primary storage device 20 to the network controller 24. Network controller 24, primary storage device
Reference numeral 30 constitutes a primary storage side network node 30 in the token ring network 28. The token ring network 28 includes a primary storage side network node 30 having a network controller 24 provided in the token ring 32 and a secondary storage side network node 34.
There is. Reference numerals 30 and 34 correspond to the network nodes 12 and 14 in FIG.

The network node 34 is configured as follows.
Network controller 36 (corresponding to 17 in FIG. 1) interposed in the token ring 32 for temporarily storing received data
It has a FIFO 38, a buffer memory (hereinafter referred to as a secondary storage device) 40, an address bus 42, data buses 44 and 45, and a buffer memory arbiter 46 as its constituent elements. The data bus 44 is used for data transfer between the network controller 36 and the reception data temporary storage FIFO 38, and the data bus 45 is used for the reception data temporary storage FIFO 38 and the secondary storage device.
It is used for data transfer to and from the secondary storage device 40 and the network controller 36.
The address bus 42 transfers the page address to the secondary storage device 40. The buffer memory arbiter 46 controls data transfer of the network controller 36, the reception data temporary storage FIFO 38, and the secondary storage device 40.

As shown in FIG. 3, the network controller 36 has a receiving circuit 50, an outgoing page number register 52, a returning page number register 54 and a transmission control circuit 56. The receiving circuit 50 receives the outgoing page number register 52 via a bus 58. , Is connected to the recovery page number register 54 and the transmission control circuit 56,
For temporary storage of received data via bus 58 (data bus 44)
Connected to FIFO38. The duplicate page number register 54, the address bus 42, the data bus 45, the secondary storage device 40, and the buffer memory arbiter 46 correspond to the data insertion unit 18 in FIG.

For data transfer between the primary storage device 20 and the secondary storage device 40 in this system configuration, a fixed-length memory page unit is inserted into the round-trip communication data accommodating section D of the round-trip communication frame (see FIG. 4). This is performed by transferring the round-trip communication frame via the token ring 32. In FIG. 4, SA is the communication data name display section (communication page number) (corresponding to the response information in FIG. 1), DA is the recovery data name display section (recovery page number) (recovery data in FIG. 1). It corresponds to the transmission request information). The shaded area is the MAC
It is an area for control.

In the processing in the central processing unit of the computer system, when there is a request to transfer a part or all of the storage contents stored in the primary storage device 20 to the secondary storage device 40, the request is sent through the transmission request line 26. Via the network controller 24.

In FIG. 2, the token ring 32 corresponds to the transmission line 10 in FIG. The primary storage side network node 30 is
The secondary storage side network 34 corresponds to the transmitting node 12 in FIG. 1, and the secondary storage side network 34 corresponds to the receiving node 14 in FIG. Secondary storage device 40 of primary storage side network node 30, address bus
42, data buses 44 and 45, outgoing page number register 52, transmission control circuit 56, and buffer memory arbiter 46
Corresponds to the transmitting means 8 in FIG. The receiving circuit 50 of the primary storage side network node 30, the outgoing page number register 52, and the buffer memory arbiter 46 correspond to the releasing means 7 of FIG. Primary storage side network node
30 duplicate page number register 54, and transmission control circuit 56,
Further, the buffer memory arbiter 46 corresponds to the inserting means 9 of FIG. 1, and includes the receiving circuit 50 of the secondary storage side network node 34, the duplicate page number register 54, the address bus 42, the secondary storage device 40, the data bus 45, The transmission control circuit 56 and the bus memory arbiter 46 correspond to the transmission means 17 in FIG.

Its network controller 24 is a token ring 32
Take in the above token and acquire the transmission right. Then, the following pieces of information supplied from the primary storage device 20: (1) Page number of data to be transferred from the secondary storage device 40 to the primary storage device 20; (2) Secondary storage from the primary storage device 20. The page number of the data to be transferred to the device 40, (3) The data to be transferred from the primary storage device 20 to the secondary storage device 40 are sequentially transmitted to the token ring 32, and the round-trip communication frame (see FIG. 4). ) Is inserted and transmitted to the corresponding information insertion unit.

Thus, the frame transmitted through the token ring 32 is received by the network node 34. The reception is performed by the receiving circuit 50 in the network controller 36, and the information (1) and (2) at the time of the reception are set in the duplicate page number register 54 and the outgoing page number register 52, respectively. Then, the contents of the restored page number register 52 are
Is transmitted to the secondary storage device 40 via the, and the signal is also transmitted to the buffer memory arbiter 46. In the secondary storage device 40, the information (1) is analyzed and the data (recovery data) corresponding to the page number is read out under the control of the buffer memory arbiter 46 and secondary storage is performed via the data bus 45. Transfer to the network controller 36 on the side.

Information (3) received after the above information (1) and (2) is written to the received data temporary storage FIFO 38 under the control of the buffer memory arbiter 46 during the processing of the restored data.

In addition, the frame received by the receiving circuit 50 is the data bus 44
Is directly sent to the transmission control circuit 56 via the network and is transmitted to the downstream side of the token ring 32 with respect to the secondary storage side network controller 36. At that time,
The data read from the secondary storage device 40 as described above and transferred to the transmission control circuit 56 via the data bus 45 contains the round trip data in the frame transmitted to the downstream side of the token ring 32. It is inserted into the section D and transmitted to the temporary storage side network controller 30 via the token ring 32.

The data read from the secondary storage device 40 is inserted,
When the reciprocating communication frame that has made a round through the token ring 32 is received by the primary storage side network controller 30, the token is sent to release the acquired transmission right, and the received reciprocating communication frame is restored. The data is transferred to the primary storage device 20 and written there. In this way, the forward communication and the reverse communication can be completed in one round of the round-trip communication frame.

When the data requested from the primary storage side has been transferred to the secondary storage side network controller 36, a termination signal is sent to the buffer memory arbiter 46 and, under the control, read from the reception data temporary storage FIFO 38. The data is written via the data bus 45 to the storage area in the secondary storage device 40 designated by the information (2) in the outgoing page number register 45.

The token ring network 28 may be configured as the token ring network 28 in which three or more network nodes are provided in the token ring 32. Further, the data transfer from the reception data temporary storage FIFO 38 to the secondary storage device 40 may be performed in another transfer mode. or,
It goes without saying that the outgoing and incoming data need not always be transmitted and received in pairs.

〔The invention's effect〕

As described above, according to the present invention, the round trip communication frame can be completed between the network nodes to be communicated with each other, so that the forward and reverse communications between the two network nodes can be completed. The required communication time can be shortened and the traffic can be reduced accordingly, which can contribute to the construction of a fast and efficient round trip communication system.

[Brief description of the drawings]

FIG. 1 is a block diagram of the principle of the present invention, FIG. 2 is a diagram showing an embodiment of the present invention, FIG. 3 is a detailed configuration diagram of a network controller of the embodiment of the present invention, and FIG. 4 is an embodiment of the present invention. FIG. 5 is a diagram showing a round-trip communication frame used, and FIG. 5 is a diagram showing a sequence of a conventional system. In FIGS. 1 and 2, 10 is a ring transmission line, 11 is a response information section (outgoing data name display section SA), 12,14,30,34 are network nodes, and 13 is a return data transmission request information section (recovery data). Data name display area D
A), 16 is a data accommodating section (round trip data accommodating section), 17, 24, 36 are network controllers, 18 is a data inserting section, and 19 is a memory.

Claims (1)

(57) [Claims] 1. A transmission means for inserting, in a frame, data to be transmitted from a transmitting node, which has acquired a transmission right, of a plurality of nodes provided on a transmission line, to another node to which the data is to be transmitted. In a data transmission system including a releasing unit for releasing the transmission right of the transmitting node when the frame returns from the receiving node via the transmission path, when the transmitting node wants to receive data from the receiving node,
While the transmitting node is provided with inserting means for inserting the reconstructed data transmission request information into the frame transmitted to the receiving node by the transmitting means of the transmitting node, the receiving node responding to the response information of the response information section in the received frame, When it is detected that the replica data transmission request information is inserted in the received frame, the receiving node is provided with transmitting means for inserting the required data into the data accommodating portion of the frame and transmitting the frame to the transmitting node. A data transmission system characterized by being provided.