JP2713271B2 - Transport communication control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transport communication control method for controlling communication between computer systems (communication control at a transport layer level), and more particularly to a transport communication control method for monitoring a communication failure by monitoring a timer. About the method.

[0002]

2. Description of the Related Art The following patent publications describe prior art relating to the present invention. JP-A-4-156644 ("Communication control device")
JP-A-62-193438 (JP-A-62-193438) (JP-A-62-193438) (JP-A-61-248637) (JP-A-61-248637)

Conventionally, monitoring of communication failures (monitoring of communication failures by timer monitoring) in this type of transport communication control method has been performed by one of the following methods.

A response monitoring timer is provided on the data transmitting side, and if there is no acknowledgment from the data receiving side until a predetermined time has elapsed after data transmission, it is determined that a communication failure has occurred. The technology described in the above-mentioned patent publications corresponds to this.

[0005] An information reception monitoring timer is provided on the data receiving side, and if information cannot be received within a predetermined time, it is determined that a communication failure has occurred. The technology described in the above-mentioned patent publication corresponds to this.

[0006]

The above-mentioned prior art has the following two problems.

The first problem is that in the conventional technology (the above-described technology), it is acknowledged that there is an acknowledgment from the receiving system (computer system on the data receiving side) and that the data arrives at the receiving system. Even if the data is confirmed by the local system (computer system on the data transmitting side), it cannot be confirmed until the data actually reaches the receiving application program (application program in the receiving system).

[0008] The reason is that when data reaches the receiving-side transport provider (transport provider in the receiving-side system), it is checked from the receiving-side system regardless of whether the data reaches the receiving-side application program. This is because a response is sent.

The second problem is that the conventional techniques (the techniques described above and above) cannot distinguish a failure in a communication path, a failure in a transport provider, and a failure in an application program.

[0010] The reason is that a communication failure is detected due to "the acknowledgment is not received by the transmitting system" or "the information is not received by the receiving system". Because it cannot be specified until.

According to the present invention, in view of the above points, it is possible to confirm that data has actually arrived at a receiving-side application program, and to distinguish a failure of a receiving-side application program from other failures among communication failures. Contribute to the identification of the cause of a communication failure by enabling notification to the sending application program (application program in the sending system) via the sending transport provider (the transport provider in the sending system). And a transport communication control method capable of improving maintainability.

[0012]

According to a transport communication control method of the present invention, a transmission application program for transmitting transmission data to a transmission transport provider is provided. A transmitting means of a transmitting transport provider for transmitting transmission data from the transmitting side application program as transport data to a receiving side transport provider via a lower communication path, and a transmitting means of the transmitting side transport provider. The receiving means of the receiving side transport provider for sending the timer start instruction to the timer upon storing the transport data in the receiving queue, the receiving side application program for sending the receiving request to the receiving side transport provider, If there is transport data in the receiving queue of the receiving-side transport provider when receiving a receiving request from the receiving-side application program, the transport data is delivered to the receiving-side application program as received data, and a timer stop instruction is given at the time of the delivery. Receiving notification means of the receiving side transport provider for sending the notification to the timer, and, when a certain period of time has elapsed from the reception of the timer start instruction, error notification data is transmitted to the transmitting side of the transmitting side via the transmitting means of the receiving side transport provider and the communication path. An error is sent to the sending application program based on the timer of the receiving transport provider to be sent to the receiving notifying means of the port provider and the error notification data from the timer of the receiving transport provider. Having said reception notification means receiving transport provider to send the knowledge.

[0013]

Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the transport communication control system according to the present invention.

The transport communication control system of the present embodiment includes a transmitting system 10, a receiving system 20, and a communication path 30.

The transmitting side system 10 includes a transmitting side application program 11 and a transmitting side transport provider 12.

The transmitting side transport provider 12
It is responsible for data transmission, transmitting means 13, receiving means 14,
And a reception notifying means 15.

The receiving-side system 20 includes a receiving-side application program 21 and a receiving-side transport provider 22.

The receiving-side transport provider 22
A transmission unit 23, a reception unit 24,
It is configured to include a reception notifying unit 25, a reception queue 26, and a timer 27.

Data transmission between the transport provider 12 on the transmitting side and the transport provider 22 on the receiving side is performed via the communication path 3 (a communication path lower than the transport layer level).

In general, both computer systems that perform communication are both a transmitting system and a receiving system. That is, the transport provider applied to the transport communication control method of the present embodiment and the present invention is the transmission transport provider 12.
, And also has a function as the receiving-side transport provider 22.

Next, the operation of the thus configured transport communication control system of the embodiment will be described. Here, an operation when data is transmitted from the transmission side application program 11 to the reception side application program 21 will be described.

First, in the transmission-side system 10, the transmission-side application program 11 transmits transmission data (data to be transmitted) to the transmission-side transport provider 1.
2 to the transmission means 13.

The transmission means 13 uses the transmission data as transport data via the lower-level communication path 30,
It is sent to the receiving means 24 of the receiving side transport provider 22.

The receiving means 24 stores the transport data in the reception queue 26. Also, at the time of this storage,
A timer start instruction is sent to the timer 27. Triggered by the timer start instruction, the timer 27 starts timer counting.

On the other hand, in the receiving system 20, the receiving application program 21 sends a receiving request to the receiving notifying means 25 of the receiving transport provider 22.

If there is TP data in the reception queue 26 of the transport provider 22 on the receiving side, the reception notifying means 25 transfers the transport data to the receiving side application program 21 as received data. Also,
At the time of the delivery, a timer stop instruction is sent to the timer 27.
In response to the timer stop instruction, the timer 27 stops the timer timing.

The timer 27 of the receiving-side transport provider 22 outputs an error notification indicating that a predetermined time has elapsed from the reception of the timer start instruction while the receiving-side application program 21 does not send a reception request to the reception notifying means 26. Transfer data to the receiving side transport provider 22
Via the transmission means 23 and the communication path 30 to the reception notifying means 15 of the transport provider 12 on the transmission side.

The reception notifying means 15 sends the application program 11 based on the error notification data.
Send an error notification to. As a result, the transmission-side application program 11 detects the abnormality of the reception-side application program 21 (existence of communication failure based on the abnormality,
And that the communication failure is caused by the failure of the receiving-side application program 21).

As described above, when the receiving side application program 21 does not make a receiving request for a certain period of time, the timer 27 of the receiving side transport provider 22
"No reception request for a certain period of time"
Is sent to the transmitting-side application program 11 as an error notification. Therefore, unless you receive an error notification,
The transmission side application program 11 can confirm that the data has reached the reception side application program 21 (conversely, if an error notification is received,
The transmitting side application program 11 can detect a failure of the receiving side application program 21).

The "constant time" measured by the timer 27 is determined based on an instruction from a system administrator or the like according to the characteristics of the transmitting system 10 (various performances, loads, etc.) and the characteristics of the receiving system 20. , Can be variable (see the invention of claim 2).

Next, the processing procedure of the transport provider applied to the transport communication control system of this embodiment will be described. As described above, in general, a transport provider that can be the transmitting transport provider 12 and the receiving transport provider 22 is applied to the transport communication control method of the present embodiment and thus the present invention. Here, a processing procedure regarding a transport provider applied to both of the transmitting side and the receiving side will be described.

FIG. 2 is a flowchart showing the processing procedure of such a transport provider. This procedure is
An event waiting step 201, an event type determination step 202, a data transmission step 203, an error notification data transmission step 204, a data reception queue storage step 205, a timer counting start step 206,
It comprises a receiving queue data transfer step 207 and a timer counting stop step 208.

This transport provider performs the following processing (see FIG. 2).

An event is always waiting (step 201).

When an event occurs in step 201, the type of the event is determined (step 20).
2).

Depending on the result of the determination in step 202, one of the following processes is performed.

If the event is “transmission request (reception of transmission data)”, the corresponding data (transport data) is transmitted (step 203), and step 2
It returns to the event waiting state of 01.

When the event is “time out (timer 2
If the time counted by 7 exceeds the above-mentioned "certain time", the error notification data is transmitted (step 204), and the process returns to the event waiting state of step 201.

If the event is “data reception (transport data reception)”, the data (transport data) is stored in the reception queue 26 (step 205), and timer counting is started (step 20).
6), returning to the event waiting state in step 201;

If the event is a “reception request (reception of reception request)”, the transport data in the reception queue 26 is delivered to the application program (reception-side application program 21) as reception data (step 207), and the timer The timing is stopped (step 208), and the process returns to the event waiting state of step 201.

[0042]

As described above, the present invention provides the following 2
Has two effects.

The first effect is that when the receiving application program does not receive data due to the failure, the fact can be recognized by the transmitting application program.

The reason is that the receiving-side transport provider performs timer monitoring of the pull-up (reception) of data (data to be transmitted) by the receiving-side application program, and issues a predetermined error notification when the data is not pulled up. It is.

The second effect is that it is possible to distinguish between a failure in a layer below the transport provider (a failure in the transport provider on the receiving side, a failure in the communication path, etc.) and a failure in the application program on the receiving side.

The reason is that if data cannot be pulled up due to a failure in the receiving application program, there is an error notification from the receiving transport provider. This is because it can be determined that the failure is in the layer below the transport provider.

The transport communication control method of the present invention
With the above two effects, it is possible to contribute to the identification of the cause of the communication failure, and it is possible to improve maintainability.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a transport communication control system according to an embodiment of the present invention.

FIG. 2 illustrates a processing procedure of a transport provider (a transport provider that can be both a transmitting-side transport provider and a receiving-side transport provider) applied to the transport communication control method of the present embodiment illustrated in FIG. It is a flowchart shown.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Sending system 11 Sending application program 12 Sending transport provider 13, 23 Sending means 14, 24 Receiving means 15, 25 Receiving notification means 20 Receiving system 21 Receiving application program 22 Receiving transport provider 26 Receiving queue 27 Timer 30 Communication path 201 Event waiting step 202 Event type determination step 203 Data transmission step 204 Error notification data transmission step 205 Data reception queue storage step 206 Timer clock start step 207 Receive queue data transfer step 208 Timer timer stop step

Claims (3)

(57) [Claims] 1. A transport communication control method for monitoring a communication failure by monitoring a timer, comprising: a transmitting application program for transmitting transmission data to a transmitting transport provider; and transmitting data from the transmitting application program to transport data. The transmitting means of the transmitting transport provider for transmitting to the receiving transport provider via the lower communication path, and the transport data from the transmitting means of the transmitting transport provider are stored in a reception queue. A receiving means of a receiving-side transport provider that sends a timer start instruction to a timer, a receiving-side application program that sends a receiving request to the receiving-side transport provider, and a receiving request from the receiving-side application program. If there is transport data in the receiving queue of the receiving-side transport provider when the transmission is performed, the receiving-side transport provider sends the transport data to the receiving-side application program as receiving data, and sends a timer stop instruction to the timer at the time of the transfer. Receiving notification means for receiving a timer start instruction, and sending error notification data to the transmitting means of the receiving transport provider and the receiving notifying means of the transmitting transport provider via the communication path when a predetermined time is counted from the reception of the timer start instruction. The timer of the receiving transport provider, and the receiving of the receiving transport provider that sends an error notification to the transmitting application program based on the error notification data from the timer of the receiving transport provider. A transport communication control method, comprising: a notifying unit. 2. A system according to claim 1, further comprising a timer provided by a receiving-side transport provider capable of changing a “fixed time” measured from a timer start instruction in accordance with characteristics of the transmitting-side system and characteristics of the receiving-side system. The transport communication control method according to claim 1, wherein 3. A transport provider, which can be both a transmitting transport provider and a receiving transport provider, includes an event waiting step, an event type determining step, a data transmitting step, an error notification data transmitting step, 3. The transport communication control method according to claim 1 or 2, wherein the processing is performed by a procedure including a receiving queue storing step, a timer counting start step, a receiving queue data delivery step, and a timer counting stop step. .