JPS6349871A - Controlling system for switching system - Google Patents

Abstract

PURPOSE:To prevent an ineffective holding call due to loss of the important control information caused by a system switching action, a high-load state caused in a processing restart mode, by processing and storing the specific important control information received from a terminal in a system switch mode through a terminal interface part. CONSTITUTION:If the 1st central control part 11 has abnormality, the fault information (f) on the part 11 is sent to a system switching part 15. The part 15 switches the part 11 to a waiting mode from a working mode and the 2nd central control part 12 to a working mode from a waiting mode by the system selection signals (d) and (e) respectively. A terminal interface part 13 detects these system switching actions by both signals (d) and (e) and is put under a special action mode to process and store the specific information out of the control information received from a terminal 14. The part 12 delivers the information to the part 13 to release a specific state when preparation is through for a normal action. Then the part 13 sends the stored information to the part 12.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention provides a control system that achieves high reliability through a redundant configuration, in which switching is performed from an operating device to a waiting device. This invention relates to a system switching control method for restarting processing when a system failure occurs.

(Prior art) Like a computer system or switching system that accommodates a large number of terminals, it consists of a relatively small-scale terminal interface unit, a central control unit that can control a large number of these units, and a communication path that connects the two. In the Zadaru system, the central control unit has a redundant configuration and is replaced in the event of a failure to achieve high reliability. However, in such a system with a redundant configuration, information may be lost between the central control unit and the terminal interface unit when the central control unit is switched, and the user of the terminal during communication may experience high It is conceivable that frequency control information is provided to the system. In this case, there is a risk that an invalid held call will occur due to loss of important information at the stage of restart processing, or that restart processing will become impossible due to a high load of control information.

(Problems to be Solved by the Invention) As described above, in the conventional redundant configuration control system, there is a problem in that the system may malfunction during a short period of time between system switching and reprocessing.

The object of the present invention is to provide a system switching system that solves these problems.

[Structure of the Invention] (Means for Solving the Problems) The present invention monitors the operation/status of a redundant central control unit at a terminal interface unit and, after detecting system switching, The present invention is characterized in that predetermined information among the control information is selectively processed and stored in the terminal interface section, and is sent to the central control section after the restart processing is completed.

(Function) According to the present invention, by processing and storing specific M-required sterilization information from the terminal at the time of system switching in the terminal interface section, it is possible to prevent loss of this important sterilization information. It is possible to eliminate the occurrence of invalid held calls after restarting. It is also possible to prevent the occurrence of a high load state during restart processing.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a control system configuration diagram of an example of an actual exchange system. 11 and 12 are first and second central control units, respectively, 13 is a terminal interface unit, 14 is a terminal, and 15
is the system switching section. Although only one terminal 14 is shown, a plurality of terminals are actually connected to one terminal interface section. Between the terminal 14 and the interface section 13, and between the interface section 13 and the first. The second central control units 11 and 12 are connected by a bidirectional communication path.

1st. The second central control units 11 and 12 respectively have a terminal interface unit 13 and control information (a).

(b) and internal failure information (f).

(a) is sent to the system switching unit 15. The system switching unit 15 outputs operating/low state designation signals (d) and (e) to the terminal interface unit 13 according to the combination of failure information (f), (Q) and other factor information (h). do. signal (d),
(e) at least the first and second central control units 11.1;
2 will not be in the operating state at the same time. For example, when the first control section 11 is in the operating state, the second control section 11
Control! 1181112 is in a standby state, and the terminal 14 is exchanging control information only with the first control unit 11 via the interface unit 13.

Here, system switching control when an abnormality occurs in the first central control unit 11 is performed as follows. First central control unit 1
When the failure information (f) is transmitted from 1 to the system switching unit 15, the system switching unit 5 uses the system selection signals @ (d) and (e) to
The second central control section 11 is switched from operating to special low mode, and the second central control section 12 is switched from standby mode to operating mode. The terminal interface unit 13 receives this system selection signal (d) (e)
This system switching can be detected by monitoring. After this, the terminal interface unit 13 enters a special operating state. In the special state, the terminal interface 13 itself processes and stores specific information among the control information from the terminal 14. For example, when there is a disconnection request from the terminal 14, the terminal interface unit 13 responds to the terminal 14 that it is inactive or requesting disconnection, and temporarily stores the request. do. This is because if the disconnection request information is lost, even if the central control unit subsequently starts operating, connection requests from other terminals to this terminal 14 will be rejected, resulting in serious inconvenience. For other service requests such as connection requests,
The terminal interface unit 13 responds to the terminal 14 with a notification that it is inactive, unable to connect, or unable to provide service. and the second
After the central control unit 12 of the central control unit 12 is switched from standby to active and ready for normal operation, it sends information to cancel the special state to the terminal interface unit 13, and the terminal interface unit 13 receives this information. to cancel the special state and send only the accumulated disconnection requests to the second central control unit 1.
Send to 2. This prevents the loss of disconnection request information from the terminal 14 at the time of system switching.

FIG. 2 shows a specific internal configuration of the terminal interface section 13 for controlling the special state as described above. As shown in the figure, the terminal interface unit 13 includes rise detection circuits 21 and 22 that detect the rise of the system selection signals (d) and (e) from the system switching unit 15, and a logic sum of these outputs. There are a gate 23, a flip-flop 24 controlled by the output of the gate 23, and an interface control circuit 25.

FIG. 3 is an operation time chart of the circuit shown in FIG. 2. When the rising edge of the selection signal (d) or (e) from the system switching unit 15 is detected, the Q output of the flip-flop 24 becomes HI+ level, and this is given to the control circuit 25 as information indicating the standby state. During this time, specific information among the information from the terminal 14 is accumulated in the interface section 13 as described above.Then, when the switching operation is completed, the second central control section 12 receives information indicating that normal operation preparation is complete. When the signal is sent, the control circuit 25 detects this, resets the flip-flop 24 to release the special state, and sends the held control information to the second central control section 12.

In this way, according to this embodiment, loss of important υ control information at the time of system switching in a redundant switched line system can be prevented,
System reliability can be improved.

The present invention is not limited to the above embodiments, and can be implemented with various modifications without departing from the spirit thereof.

[Effects of the Invention] As described above, according to the present invention, in a control system with a redundant configuration, the terminal interface unit autonomously detects system switching, selectively accumulates and holds important control information, and performs system switching. It is possible to prevent the occurrence of invalid held calls due to the loss of important control information accompanying this, and it is also possible to prevent the occurrence of a high load state when processing is restarted.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an exchange system according to an embodiment of the present invention;
FIG. 2 is a diagram showing an example of the configuration of the special state processing circuit section of the terminal interface section, and FIG. 3 is a diagram showing its operation time chart. 11.12... Central control detail, 13... Terminal interface section, 14... Terminal, 15... System switching section, 2
1゜22... Rise detection circuit, 23... OR gate, 24... Flip-flop, 25... Interface section control circuit. Applicant's agent Patent attorney Takehiko Suzue Figure 1 Figure 2

Claims (1)

[Claims] one terminal interface section, and first and second terminals connected to this interface section through bidirectional communication paths, respectively;
a central control unit, a plurality of terminals connected to the terminal interface unit, and a control that allows only one of the first and second central control units to communicate with the terminal interface unit and puts the other in a standby state. In the control system, the terminal interface section has means for monitoring the operation/standby state of the first and second central control sections, and the terminal interface section has means for monitoring the operation/standby state of the first and second central control sections. After detecting switching, a part of the control information from the terminal is selectively processed and stored in the terminal interface section, and after the restart processing is completed, this is sent to the first and second central control sections. System switching control method.