JPH0126217B2 - - Google Patents

Description

[Detailed Description of the Invention] (1) Technical Field of the Invention The present invention provides a non-communication time monitoring control that monitors the non-communication time of a line and performs a line disconnection process if communication is not resumed within a predetermined time. Regarding the method,
In particular, the present invention relates to a line non-communication time monitoring control system having a non-communication time monitoring means for avoiding excessive line disconnection.

(2) Background of the technology Conventionally, in data processing systems, some type of communication network failure, such as line disconnection,
If the terminal enters a no-communication state due to a terminal failure (terminal wire disconnection, abnormal termination of terminal software, etc.), no response from the terminal operator, etc., the host computer and the terminal with a time monitoring function will monitor the no-communication time. If communication is not resumed within a certain period of time (hereinafter referred to as no-communication monitoring time or simply monitoring time), it is determined that a failure condition has occurred, the line is disconnected, and recovery measures are taken for a long time or separately. The current practice is to prevent the line from being held until the end.

In such cases, such as inquiry work,
In cases where the terminal operator proceeds with the process in a conversational manner, the non-communication monitoring time is set relatively long, for example around 10 minutes, to allow for time for the terminal operator to think, and moreover, the terminal operator uses a public telephone line. If the line is disconnected due to a failure on the terminal side, an operational error, etc., the line will be kept in a busy state until the no-communication monitoring time on the host side has elapsed, even if the failure is resolved immediately. During the no-communication monitoring time, the line cannot be used again. As a result, a situation often occurred in which the line could not be used effectively.

(3) Prior art and problems Figure 1 is a block diagram of a data processing system using the conventional no-communication time monitoring and control method.
The figure schematically shows part of the control procedure.

In FIG. 1, 1 is a terminal system, 2 is a host system, 3 is a terminal-side application, and 4 is a terminal system.
is a line control unit, 5 is a time monitoring function placed in the line control unit, 6 and 7 are line control units NCU, and 8 is a line control program NCP/virtual communication access method.
VTAM, 9 indicates a time monitoring function placed in the NCP/VTAM, and 10 indicates a host-side application.

Line disconnection detection control in the conventional system shown in FIG. 1 is performed as follows. First, when disconnecting the line from the terminal side during normal operation, the control procedure shown in FIG. 2 is taken. In the terminal system, when the application instructs to close the line due to the end of the job, the line control unit 4 closes the line on the host side.
Send a line disconnection command to NCP/VTAM, mutually confirm, and perform line disconnection processing. On the other hand, line disconnection during business processing, which is an abnormal case, occurs when the time monitoring function of the line control unit monitors the time of no communication, such as when the operator does not respond, and data is not sent or received for a certain period of time. , is recognized as an abnormal state and activated. In addition, in the case of line abnormality, line disconnection processing is performed immediately, but while the state or cause of line disconnection is unknown, at least until a certain no-communication monitoring time has elapsed.
The system (particularly the host) holds the NCU in use, making it impossible to reuse it within a period of time.

The disadvantage of the conventional method described above is that when an operator performs conversational business processing, if the operator does not return a response, the line is subject to no-communications time monitoring, and the line is disconnected after a certain monitoring period has elapsed. This occurs because the monitoring time is usually set to be sufficiently long, taking into account the operator's thinking time, input operation time, etc., so that line disconnections do not occur too often. Furthermore, as mentioned above, if the line is disconnected due to an operational error or line failure, the public line busy state will be maintained until a certain monitoring time has elapsed, so during that time, for example, 10
There is a problem that the NCU is occupied for ~15 minutes.

(4) Purpose of the Invention In order to improve the problems of the conventional method described above, the present invention makes monitoring of idle time as short as possible, and makes it practical to pay attention to the time when the line cannot be used due to busy conditions. The object of the present invention is to provide a method that can shorten the process to the extent that it does not occur.

(5) Structure of the Invention In order to achieve the above-mentioned object, the present invention provides a method in which, for example, when the host no-communication monitoring time is T and the terminal no-communication monitoring time is t, T>t and both are as small as possible. (for example, T; 30 seconds,
t; 20 seconds), and when the no-communication time exceeds the monitoring time t on the terminal side, a dummy message is automatically sent from the terminal to the host without immediately disconnecting the line as in the conventional method. A state in which communication appears to be occurring is created, thereby initializing the no-communication monitoring state. On the host side, the received dummy message is ignored and the time monitoring function of the line control unit is simply restarted. The line disconnection process can only be activated after this operation has been repeated a predetermined number of times. Further, the number of repetitions described above can be selected depending on the type of business.

In the configuration for that purpose, the present invention provides a first device and a second device each having a non-communication time monitoring function.
In a data processing system where messages are transmitted between devices, the system's non-communication monitoring time T
is set as the no-communication monitoring time in the second device, the no-communication monitoring time in the first device is set to t, which is smaller than T, and the no-communication time between the first device and the second device is set as the no-communication monitoring time in the first device. Every time the non-communication monitoring time t exceeds, a dummy message that is treated as invalid information is transmitted from the first device to the second device, thereby initializing the non-communication time monitoring function of the first device and the second device, and the above-mentioned non-communication time monitoring function is initialized. When a dummy message is transmitted every time the communication time exceeds t and the number of times the no communication time monitoring function is initialized exceeds a certain value, or when a line abnormality occurs, the line is disconnected. It is a feature.

(6) Examples of the invention The present invention will be described in detail below using examples.

FIG. 3 is a configuration diagram of a system according to an embodiment of the present invention. In the figure, 1 is a terminal system, 2 is a host system, 8 is a line control section in the terminal system, 9 is a time monitoring section, 10 is a dummy message transmission section,
11 is a retry count monitoring unit, 12 is a line disconnection processing unit on the terminal system side, 13 is an NCP/VTAM in the host system, 14 is a dummy message receiving unit, 1
Reference numeral 5 indicates a time monitoring unit, and reference numeral 16 indicates a line disconnection processing unit on the host system side.

The time monitoring unit 9 in the terminal system has a clock (clock counter) that measures the non-communication time and a monitoring time t which is the time limit of the non-communication time. The monitoring time t is desirably as short as possible, and is selected to be, for example, 10 to 20 seconds, giving some margin to the operator's standard response time in conversational business processing. The dummy message transmitting section 10 is activated by a signal from the time monitoring section 9 when the non-communication time exceeds the monitoring time t, and transmits a dummy message to the host system, and also clocks the clock of the time monitoring section 9. Reset. The clock is always reset if the message transmission/reception is performed correctly, regardless of whether the message is a dummy message.

The retry count monitoring unit 11 compares the number of times a dummy message is sent when the non-communication time exceeds t with a predetermined number of retries N, and when it exceeds N, instructs the line disconnection processing 12 to disconnect the line. Let it process. The number of retries N can be changed depending on the type of business processing. For example, 0 times for non-conversational business processing such as file transmission, and 20 times for conversational business processing.
times, etc.

The time monitoring unit 15 in the host system, like the time monitoring unit 9 in the terminal system, has a clock (clock counter) that measures the non-communication time and a monitoring time T.
It has The monitoring time T is a value larger than at least the monitoring time t of the terminal system, for example
It is set at about 30 seconds. The clock in the time monitoring unit 15 is reset when the message is correctly transmitted and received. Therefore, the clock is reset each time the dummy message receiving section 14 receives a dummy message from the terminal system, and the clock of no communication time based on the monitoring time T is restarted each time.

FIG. 4 is a flow diagram showing the control procedure of the embodiment system shown in FIG. 3. Hereinafter, the operation of the embodiment system will be explained according to the flowchart.

First, on the terminal side, in order to perform a certain business process, a communication connection line with the host side is secured by an application line open process. At this time, in the initial value setting process of the line control section, a dummy message for use in non-communication time monitoring control is set.

Next, transmission and reception of messages by READ/WRITE processing between the terminal and the host application is started. At this time, the number of retries N when the no-communication monitoring time has exceeded is set in the line control unit based on information from the application. As described above, the number of retries N can be changed depending on the content of the work performed by the application, the presence or absence of a conversation format, etc.

The line control unit checks the completion of transmission and reception of the message, and if an abnormality is detected, initiates line disconnection processing. On the other hand, if normal completion is detected, the application is requested to send and receive the next message, and at the same time,
Start monitoring idle time.

If the no-communication time exceeds the monitoring time t, check whether the next number of retries will be greater than N,
If it becomes larger than N, line disconnection processing is activated. On the other hand, if it is smaller than or equal to N, dummy message transmission processing is activated. Here, the dummy message that was initially set in the line control unit is sent to the host. On the host side, if the received message is a dummy message, it is ignored as invalid, and if it is a legitimate message, it is processed.

(7) Effects of the Invention As described above, according to the method of the present invention, the dummy message works as a means for automatically extending the monitoring time T in small increments, and by setting the number of retries to an appropriate value, T Even if the value of is small, it is possible to have substantially the same effect as having a sufficiently long monitoring time. In addition, since the difference between t and T can be kept relatively small, even if the public line becomes busy due to a line abnormality, the monitoring time T can be reached immediately. Unavailable time can be significantly reduced compared to conventional methods, and line utilization can be improved.

[Brief explanation of drawings]

Fig. 1 is a system configuration diagram for explaining a conventional no-communication time monitoring control method, Fig. 2 is an explanatory diagram of its control procedure, Fig. 3 is a configuration diagram of an embodiment of the present invention, and Fig. 4
The figure is a flowchart of the control procedure. In the figure, 1 is the terminal system, 2 is the host
System, 8 is line control section, 9 is time monitoring section, 1
0 is a dummy message transmitting unit, 11 is a retry count monitoring unit, 12 is a line disconnection processing unit, and 13 is an NCP/
VTAM, 14 is a dummy message receiving section, 15 is a time monitoring section, and 16 is a line disconnection processing section.

Claims (1)

[Claims] 1. In a data processing system in which a message is transmitted between a first device and a second device, each of which has a non-communication time monitoring function, the non-communication monitoring time T of the system is calculated by the second device. The non-communication monitoring time in the first device is set to t which is smaller than T, and the non-communication monitoring time between the first device and the second device is set as the non-communication monitoring time t in the first device. Each time t exceeds t, a dummy message that is treated as invalid information is transmitted from the first device to the second device, thereby initializing the non-communication time monitoring function of the first device and the second device, and the above-mentioned non-communication time exceeds t. The line wireless communication system is characterized in that the line is disconnected when the number of times the dummy message is transmitted and the no-communication time monitoring function is initialized each time it exceeds a certain value or when a line abnormality occurs. Communication time monitoring control method. 2. In the above item 1, the number of times the dummy message is transmitted and the idle time monitoring function is initialized each time the idle time exceeds t is changed according to the type of business process. Line idle time monitoring and control method.