JPS63268328A - Communication system - Google Patents

Abstract

PURPOSE:To facilitate very efficient data transmission processing as a whole by giving a transmission request to a 1st communication controller, giving the transmission request to a 2nd communication controller when a busy notice is returned from the 1st communication controller and sending a data through the 2nd communication controller. CONSTITUTION:In detecting a transmission request, a communication controller 4 sends a transmission request to a gateway 3-1 (GW1). In receiving the busy report from the GW1, the transmission request is transferred next to a GW 2. Whether or not the transmission request is received by the GW2 is discriminated, and when the request is accepted, the actual data transmission is started, the data transmission with other communication line 2 is applied via the GW2 while whether or not the data transmission is finished is being monitored. Thus, the data transmission route is revised dynamically by connecting plural sets of gateways to the LAN even without so much large scale of the gateways provided and the relief of load of each gateway and the decentralization of the load are easily realized.

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a communication system, particularly a communication system (hereinafter referred to as a local area network) in which a plurality of information processing devices are connected to the same transmission path and can mutually transmit data. or LAN), and a communication control device (hereinafter referred to as gateway or LAN) having a protocol conversion function on this LAN
This relates to a communication system that enables data transmission to other communication lines via this gateway by connecting a gateway (denoted as W).

[Prior Art] Conventionally, in this type of communication system, when data is transmitted to other communication lines via a gateway, the transmission speed on the LAN is generally much faster than the communication speed of other communication lines. Therefore, when data transmission is concentrated on the gateway at one time, data transmission may be hindered. As a countermeasure to this problem, one gateway itself has an interface with multiple other communication lines, and the use of multiple other communication lines is fully controlled based on flow control within the gateway. ing.

However, in the case of such a gateway, the functions of the gateway itself are large, so the scale of the gateway itself becomes large and expensive. Also, since functions are concentrated in one gateway, if an abnormality occurs in the gateway itself, data transmission with other communication lines becomes immediately impossible.

[Objective] The present invention eliminates the drawbacks of the conventional example described above, and at the same time dynamically changes the data transmission route based on flow control in the gateway, thereby reducing the load on the gateway. The purpose of the present invention is to provide a communication system that enables more uniform load sharing to gateways and that can easily perform extremely efficient data transmission processing as a whole.

[Example] An embodiment of the present invention will be described below with reference to one drawing.

FIG. 1 is an overall configuration diagram of a communication control processing system showing an embodiment of the present invention. In the figure, l denotes a LAN transmission path, 2-1.
2-2.2-3 is public line, other communication line such as private line, 3-1゜3-2.3-3 is LAN and other communication line 2-
Gateways controlling the interface with 1.2-2.2-3, 4-1..., 4-11..., 4-21...
・The first prize is a communication control device 5-1 that controls the interface between the LAN and the information processing device.

5-11..., 5-21..., etc. are various information processing devices.

Next, a block diagram of the gateway is shown in FIG.

In FIG. 2, 30 is a LAN interface unit that controls the interface between the LAN transmission line l and the gateway, 31 is an MPV that controls the entire gateway, and 3
2 is a storage unit for storing and editing various control information and data information actually passing through the gateway between the gateway and the communication line and LAN, and 33 is a communication line interface unit that controls the interface between the gateway and the communication line. It is.

Next, a block diagram of the communication control device is shown in FIG.

In FIG. 3, 40 is a LAN interface unit that controls the interface between the LAN and the communication control device; 41
42 is a storage unit for storing and editing various control information between the communication control device, the information processing device, and the LAN, and data information actually passing through the communication control device. , 43 is a terminal interface section that controls the interface between the communication control device and the information processing device.

Hereinafter, a communication control procedure according to an embodiment of the present invention will be explained in detail with reference to the flowcharts of FIGS. 1, 4, and 5.

First, the data transmission procedure in the communication control device 4 will be explained with reference to the flowchart shown in FIG.

The communication control device 4 waits until a transmission request is made from the information processing device 5 at Sl. If a transmission request is detected, the process proceeds to S2, and the transmission request is transferred to the gateway 3-1 (hereinafter referred to as GWI). If a busy report is notified from the GWI in S3, then in 84 the transmission request is transferred to the GW2. In S5, it is determined whether the GW2 has accepted the transmission request, and if it has been accepted, the process proceeds to S6 to start actual data transmission, and in S7, it is monitored whether the transmission request has been completed or not. Performs data transmission with. If the end is detected in S7, the process returns to Sl.

If it is confirmed in S3 that the GWI has accepted the transmission, proceed to S8 and monitor whether the actual data transmission ends in 39 before starting data transmission with other communication line 2 via the GWI. Let's do it.

If the end is detected in S9, the process returns to SL.

Further, if a busy report is made from the GW 2 in S5, the process proceeds to SIO, notifies the information processing device 5 of the transmission load, and returns to S1.

Next, the data transmission procedure in the gateway 3 will be explained with reference to the flowchart shown in FIG. 755.

The gateway 3 waits for a transmission request to be transferred from the communication control device 4 in S20. If the transmission request has been transferred, the process advances to S21 and it is determined whether the number of channels currently being transmitted through the gateway 3 is at the n end of the Max value.

The number of channels currently transmitting is the number of channels that have received a transmission request from the gateway 3 or the communication control device 4, and are currently transmitting data after accepting the request. This is the number of channels that can be operated simultaneously. Although the number of channels currently being transmitted is used here to simplify the explanation, in reality, it is considered together with the number of channels currently receiving based on the reception request from the communication line 2 side.

If it is less than the Max value n in S21, proceed to S22,
A virtual channel is assigned to clarify the destination of transmission and reception as seen from the gateway 3, and the number of channels is increased by 1.

Next, in S23, actual data transmission is started, and the data from the communication control device 4 is transferred to the communication line 2, and the data from the communication line 2 is transferred to the communication control device 4 while converting the protocol, and in S24, the data is transmitted. Execute while monitoring whether it completes. When the end of data transmission is detected, the corresponding channel is released, the number of channels is decremented by 1 in S25, and S20
Return to

In S21, when the number of channels reaches the maximum value n,
Proceeding to S26, the communication control device 4 that has transferred the transmission request
A busy report is sent to the host, and the process returns to S20.

In this embodiment, the communication control device 4 first transmits the GWI
We have described a method in which the communication control devices 4-1 to 4-10 transmit the communication to GW1-+GW2 in the order of The control devices 4-11 to 4-20 can also perform the above-described transmission procedure in the order of GW2→GWI. In addition, three or more GWs are grouped in the same way, and GWl-+G
Those executed in the order of W2 → GW3, GW2 → GW3 → G
If applied to something that is executed in WI order, a more efficient load-balanced communication control processing system will become possible. In addition, the order of GWI → GW2, etc. is also changed after GWI becomes busy.
GW2→ until notification of busy release from WI
It is also possible to apply a method of dynamically changing the order of GWI to enable more dynamic response.

[Effect] As explained above, according to the present invention, even if the gateway is not very large-scale, by connecting multiple gateways to the LAN, data can be transmitted dynamically based on flow control at each gateway. It is possible to provide a communication system in which routes can be changed, load reduction and load distribution on each gateway can be easily realized, and overall data transmission processing efficiency can be improved.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of a communication control processing system according to an embodiment of the present invention, and FIG. 2 is a block diagram of a gateway. FIG. 3 is a block diagram of the communication control device, FIG. 4 is a flowchart of the communication control procedure in the communication control device showing one embodiment of the present invention, and FIG. 5 is a flowchart of the communication control procedure in the gateway. be. Transmission path 2...other communication line 3...gateway 4...communication control device 5...information processing device 30...LAN interface unit 31...-M P V 32...Storage unit 33...Communication line interface unit 40...LA
N interface unit 41...MPU 42...storage unit 43...terminal interface unit. 20th

Claims (1)

[Claims] When a plurality of information processing devices and a plurality of communication control devices that perform data transmission with other communication lines are connected to the same transmission path, and data is transmitted from the information processing device, first, the first communication control device If a busy notification is returned from the first communication control device, a transmission request is made to the second communication control device, and the data is sent via the second communication control device. A communication system characterized by transmission.