JPH05207138A - System for controlling subscriber in subscriber controller - Google Patents

Abstract

PURPOSE:To shorten time from fault occurrence in an active system till a processing by means of a stand-by system which is changed-over into the active system is restarted. CONSTITUTION:In a subscriber controller E where a subscriber control system is multiplexed, a check-sum concerning subscriber control data in a subscriber control file which is received from a host device is prepared so that subscriber control data and the check-sum corresponding to it are stored in the respective control memories Em1 and Em2 of the multiplexed subscriber control systems E1 and E2. The subscriber control system, E2 for example, which will execute subscriber control is constituted in such a way that it reads the subscriber control data from its control memory Em2, prepares the check-sum concerning to the control data, compares the prepared check-sum with the check-sum which is stored in the control memory Em2 and executes subscriber control when the check-sums coincide.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a subscriber control system in a multiplexed subscriber control device applied to ISDN, packet switching technology and the like.

[0002]

2. Description of the Related Art FIG. 2 is a block diagram showing an example of communication equipment provided with a subscriber control device 10 to which a subscriber control system of the present invention is applied. Within the scope of this drawing, the conventional example is also the same. It has a unique configuration.

The subscriber control unit E is connected between the subscriber line T and, for example, the switching network X to selectively connect the subscriber line and the line to the next station. In order to carry out this, dual control subscriber control systems E _{1 and} E ₂ are provided, and these subscriber control systems E _{1 and} E ₂ are transferred from the host device H and the control memories Em provided therein are respectively provided. _The subscriber control data stored in _{1 and} Em ₂ controls each subscriber line T and performs switching connection.

In the conventional control method of the multiplexed subscriber control device E, when a failure occurs in the working system, for example, the # 1 subscriber control system E ₁ , the # 2 subscriber control system E ₂ is used. The standby system requests the host device H to transfer a subscriber control file, which is a set of subscriber control data, and after this file is stored in the control memory Em ₂ of the standby system E ₂ , processing such as circuit switching is performed. It was configured to resume.

Therefore, there is a problem that it takes a long time from the occurrence of a failure in the active system to the restart of the processing by the standby system switched to the active system to enable communication.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to shorten the time required for the standby system switched to the active system to resume processing when a failure occurs in the active system.

[0007]

[Means for Solving the Problems] The subscriber control system is multiplexed.
In the subscriber control device E, the principle sequence of FIG.
As shown in the diagram, the subscriber system received from the host device H
Check for subscriber control data in your file-
Create a sum and multiplex subscriber control system E _1,E₂of
Each control memory Em_1,Em₂Subscriber control data to
And the checksum corresponding to this are stored and added.
A subscriber control system, such as E, which attempts to perform admission control₂Is
Its control memory Em₂Read the above subscriber control data from
In addition, a checksum for this control data
Created, this created checksum and control memory Em
₂Checksum stored in
Check-sum and perform subscriber control when the sums match.
Configured to go.

[0008]

Even if a failure occurs in one of the multiplexed subscriber control systems, it is unlikely that an abnormality will occur in the control data stored in the memory of another subscriber control system. If the control data is abnormal, the communication network will be confused. Therefore, it is necessary to give sufficient consideration to restarting the process when the active system is switched.

In order to prevent such a situation, in the present invention, a check-sum used for facilitating the detection of a data error is created for the subscriber control data, and this is added to this subscriber control data. Correspondingly stored in the control memory.

Then, when the subscriber control data is read from the control memory, if the check-sum created from the read subscriber control data and the check-sum read from the control memory match, this control data is written. Since it can be considered that there is no abnormality, this standby system can be immediately switched to the active system, and this switched active system can restart processing using this control data. The time is significantly reduced.

At this time, if the check-sum created by the subscriber control data read from the control memory of the standby system and the check-sum read from the control memory do not match, they are stored in the control memory of the standby system. Since the subscriber control data being used will also be destroyed,
As in the conventional case, the host control device transfers the subscriber control file to the subscriber control device, rewrites the contents of the control memory of the standby system, and then switches the standby system to the active system to restart the processing.

It should be noted that an appropriate block can be selected as a unit of data to be the target of the checksum to be created, but it can be set to, for example, [I would appreciate any addition of an appropriate example]. ..

Further, in FIG. 1, the subscriber control device main body shows a checksum of the subscriber control data from the host device and stores it in the control memory of each subscriber control system. As shown in the example, the check-sum may be created by the subscriber control system that has received the subscriber control data from the host device.

[0014]

FIG. 3 is a sequence diagram showing the operation of the embodiment of the present invention. Although time elapses from top to bottom, the length of time is not accurate for convenience of illustration.

In this embodiment, the checksum for the subscriber control data is created not by the subscriber control device itself but by the subscriber control system which has received the subscriber control data from the host device. Other subscriber control systems are shown as copying the subscriber control data and checksums sent from the subscriber control system that created this checksum to control memory.

In FIG. 3 (a), when the # 1 subscriber control system receives the subscriber control file from the host device, this control system checks each subscriber control data forming the subscriber control file. A sum is created and this check-sum is saved in its own control memory along with the subscriber control data, which causes this subscriber control system to begin processing as the active system.

The # 1 subscriber control system transfers the subscriber control data and the check-sum saved in its own control memory to the # 2 subscriber control system and controls the # 2 subscriber control system. Copy to memory. As a result, the # 2 subscriber control system becomes a standby state as a standby system.

When a failure occurs in the # 1 subscriber control system which is executing the process as the active system, the # 2 subscriber control system, which is the standby system, reads the subscriber control data from the control memory and outputs the check-sum. Create and compare this check-sum with the check-sum read from this control memory.

If the results of this comparison match, the control data saved in the control memory of the # 2 subscriber control system is normal, so this # 2 subscriber control system which was the standby system. To the active system and resume processing.

FIG. 3 (b) shows a checksum created from the subscriber control data read from the control memory by the # 2 subscriber control system due to a failure in the active system # 1 subscriber control system and this control. It shows the processing when the checksum read from the memory does not match.

That is, when the check-sum mismatch is detected, the # 2 subscriber control system requests the host device to transfer the subscriber control file, and the host device transfers the subscriber control file. When it comes in, it creates a check-sum for the subscriber control data that makes up this file and saves it in control memory along with the subscriber control data.

As a result, the # 2 subscriber control system resumes processing as the active system, but compared to the above case, a transfer request for the subscriber control file to the upper device and the transmission of the subscriber control file from the higher device are made. Apart from the time to check and the check-sum, there will be a total time delay before this subscriber control file is saved in control memory.

[0023]

According to the present invention, when it is confirmed by the check-sum inspection that the subscriber control data stored in the control memory of the standby system is normal, the active system and the standby system are immediately switched. As a result, not only can the period during which processing is interrupted due to a failure in the active system be significantly shortened, but a special effect that the control data of the standby system is not confused in the entire communication system is achieved. To be done.

[Brief description of drawings]

FIG. 1 is a sequence diagram showing the principle of the present invention.

FIG. 2 is a block diagram showing an example of a system to which the present invention is applied.

FIG. 3 is a sequence diagram showing an operation of the exemplary embodiment of the present invention.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Nao Koga 3-9-18 Shin-Yokohama, Kohoku-ku, Yokohama-shi, Kanagawa Prefecture Fujitsu Communication Systems Ltd. (72) Inventor Tsutomu Shioman Shin-Yokohama, Kohoku-ku, Yokohama-shi, Kanagawa Prefecture 3-9-18 Fujitsu Communication Systems Limited (72) Inventor Sumie Morita 1015 Kamiodanaka, Nakahara-ku, Kawasaki-shi, Kanagawa Fujitsu Limited

Claims (1)

[Claims] 1. A subscriber control device in which a subscriber control system is multiplexed, creates a checksum for subscriber control data received from a higher-level device, and creates a checksum for each of the multiplexed subscriber control systems. Subscriber control data and a checksum corresponding thereto are stored in a control memory, and a subscriber control system which intends to perform subscriber control reads out the subscriber control data from the control memory and executes this control. Create a checksum for the data, compare the created checksum with the checksum stored in control memory, and perform subscriber control when the checksums match. A subscriber control system in a subscriber control device characterized by the above.