JPH01318344A - Outgoing call restriction system - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Summary] Regarding a system for restricting outgoing calls when an exchange is in an abnormal light chain, the present invention enables continued call detection for subscribers while reducing the load on the exchange even in an abnormal light chain of the exchange. The purpose of this system is to provide a call restriction method that can improve serviceability.In electronic exchanges, judgment is made according to the load level of the exchange at predetermined intervals, and the high load level is increased depending on the continuation or elimination of the high load level. a call restriction level determining means for determining call restriction level 2 as shown in FIG. call restriction processing means for performing call restriction processing at predetermined intervals shorter than the predetermined period according to the number of permissible calls read from the call restriction table in accordance with the call restriction level determined by the means; Configure.

[Industrial application field]

The present invention relates to a call restriction method when an exchange is abnormally overloaded, and more particularly to a call restriction method that adjusts the number of calls to be detected in accordance with the degree of load.

During times of abnormal congestion when the load is concentrated on the exchange, the throughput (the number of calls that can be processed within a certain period of time) of the exchange decreases due to delays in dial tone, an increase in invalid processing due to lack of receivers, etc.

When such abnormal congestion occurs, there is a need for a transmission regulation system that improves throughput and improves serviceability as much as possible.

[Conventional technology]

Generally, electronic exchanges monitor the status of subscriber lines periodically (for example, every 100 m5ec) in order to detect calls from subscribers, and when a call is detected, the equipment and memory necessary for receiving dialed digits are automatically activated for the call. After this, a dial tone is sent to notify the subscriber that preparation for dial reception is complete. When the subscriber dials a desired number, the exchange detects this and performs processing to form a bus to connect to the other party.

Since such exchange processing has strict requirements for real-time performance, a limit is usually placed on the number of calls that are subject to call detection processing within one cycle (hereinafter referred to as the allowable number of calls).

However, when a disaster such as an earthquake occurs and a large number of people make calls all at once to check on the safety of their families, the load may temporarily concentrate on the switchboard, resulting in an abnormal light chain condition. .

When such an abnormal light chain occurs, the load on the switching equipment increases, and invalid processing increases due to dial tone delays, lack of equipment such as receivers, etc. [7] The throughput of the switching equipment decreases.

Conventionally, as a countermeasure against the occurrence of such an abnormal light chain, the load on the exchange is reduced by stopping the detection of subscriber calls except for important communications for a certain period of time (for example, 30 seconds), thereby reducing the number of invalid processes. I tried to suppress the increase.

[Problem to be solved by the invention]

Although the method of stopping the detection of subscriber calls when abnormal congestion occurs can greatly reduce the load on the exchange, it does not accept any calls from subscribers for a certain period of time, which reduces the serviceability of subscribers. The decline cannot be avoided.

In addition, such a system tends to be overly regulated, and even though there are many communication requests, it is suppressed so that the ability of 1゛ exchange cannot be fully utilized.

The present invention aims to solve the problems of the prior art as described above, and it is possible to continue detecting calls to subscribers while reducing the load on the exchange even when the exchange is abnormally busy, thereby improving serviceability. The purpose of this study is to provide a transmission regulation method that can improve the quality of communications.

[Means to solve the problem]

The call restriction system of the present invention is provided with call restriction level determining means 1 and call restriction processing means 3 in an electronic exchange, as shown in FIG.

The call restriction level determining means 1 determines the call restriction level by making determinations according to the load level of the exchange at predetermined intervals, and increasing or decreasing the call restriction level as the high load level continues or disappears.

The call restriction processing means 3 includes a call restriction table 2 that defines the permissible number of outgoing calls that changes depending on the level of the call restriction level. According to the number of permissible calls read out from the call restriction table 2, call restriction processing is performed at predetermined intervals shorter than the predetermined period.

[For production]

The call restriction level determination means determines the call restriction level in accordance with the load level of the exchange every predetermined period. For example, the usage rate of the processor in the electronic exchange is used as the load level of the exchange. Predetermined period T1 (for example, 20 sec
), it is assumed that an abnormal light chain state has been detected, and the average usage rate during the predetermined period T1 thereafter exceeds a predetermined value b(a> b)
%, it is assumed that the abnormal light chain state continues and the call restriction level is raised one by one.

However, when the call restriction level rises to level 4, it remains at level 4 even if the light chain state continues.

On the other hand, the average usage rate of the processor during the predetermined period T1 is b
%, control is performed to lower the call restriction level one by one.

The call restriction processing means has a call restriction table in its memory that defines the number of permissible calls that vary depending on the level of the call restriction level, and uses the data to determine the number of calls that can be made by the call restriction level determining means. Based on the permissible number of outgoing calls specified in [7], outgoing calls are restricted in normal times and in abnormal light chain situations. During normal load (level 0), a maximum of 5 calls can be processed every predetermined period T2 (100ms), but during abnormal light chaining, the number of calls that can be processed decreases as the call restriction level increases. At call restriction level 2, only one call can be processed every predetermined cycle T2, and at call restriction level 4, only one call is allowed during 5T2 cycles (500 ms).

As described above, according to the present invention, call detection can be continued even in the case of an abnormal light chain, so that serviceability for subscribers can be improved. In addition, even in the event of an abnormal light chain, there is no excessive regulation, so the capacity of the exchanger can be fully utilized.

〔Example〕

FIG. 2 is a system configuration diagram of an electronic exchange showing an embodiment of the present invention, in which 11 is a subscriber, 12 is a subscriber line, and 13 is a system configuration diagram of an electronic exchange.
is the subscriber circuit (SLC), 14 is the communication path (NW), 1
5 is a processor (CC), and 16 is a memory (MM).

A call from subscriber 11 is transferred off-hook to subscriber line 12.
It is transmitted to CCl3 via the subscriber circuit 13. MM
16 stores programs and data for the CCl3 to execute the exchange process, and the CCl3 uses these to execute the required exchange process. Also, MM16 has CCl
Data indicating the permissible number of calls detected per subscriber line monitoring cycle and the current call restriction level is stored.
Based on this, CCl3 performs call detection processing and call regulation during normal load and abnormal rotation. Call restriction level is 5
It is divided into stages, and is defined corresponding to the normal state (level 0) and the abnormal light chain state (levels 1 to 4).

The allowable number of detected calls is determined to decrease as the call restriction level increases.

Hereinafter, the call restriction method of the present invention will be explained in detail.

The call restriction system of the present invention mainly involves the following two processes.

(1) Call restriction level control processing (2) Restriction processing for each call at each call restriction level (call restriction level control processing) Figure 3 shows call restriction level control processing in each cycle in an embodiment of the present invention. It is a flowchart which shows.

In this embodiment, the predetermined period T I (20 sec
) The abnormal light chain state is detected when the average usage rate of CCl3 exceeds a predetermined aLs. Usage rate is a
When qb is exceeded, it is checked whether the call restriction level at that time is 4, and if it is 4, the call restriction level is increased by one. If the call restriction level has already reached level 4, it will remain at level 4 even if the abnormal congestion state continues thereafter.

When the CC usage rate is below a%, it is checked whether the call restriction level at that time is 0, and if it exceeds level 0, the CC usage rate is further increased to a predetermined b (b<a)%. Check whether it does not reach or not, and if it is more than bts, the CC usage rate is a
Perform the same processing as when exceeding %. On the other hand, when the CC usage rate is below b%, the call restriction level is lowered by one.

When the CC usage rate is a% or less and the call restriction level at that time is 00, the call restriction level is not changed regardless of whether the CC usage rate is b1% or more.

FIG. 4 illustrates call restriction level control according to the present invention, and shows the average CC usage rate and the call restriction level determined based on the average CC usage rate and the flow shown in FIG. In the same figure, TI = ti+, -1i indicate a predetermined period (10 sec) in which control should be performed, and time t1
The mark in is the average C at time (ti-ti-,)
It shows the C usage rate.

(1) When the normal load condition continues, the call restriction level remains at 0. At call restriction level 0, the subscriber line monitoring period T2 (100m5
A maximum of five call detections are possible for each (ec). 10
If there are more than 5 calls within 0 m5ec,
These calls are processed as new calls in the next cycle (after 100 m5ec).

+2) CC is the average CC in the period for each period T1
Calculating usage rate. At the current time t1, the average CC
When the usage rate exceeds a%, the CC increases the call restriction level from 0 to 1. In subsequent control, 100
A maximum of two call detection processes can be performed for each m5ec.

(3) Assuming that the abnormal width edge state continues from then on until time t4, the call restriction level becomes 4 at time t4.

At call restriction level 4, 4T2 cycle period (400m5ec)
does not perform call detection processing, and performs at most one call detection processing in the next fifth cycle.

(4) If the average CC usage rate at time t5 becomes less than b% due to the regulation of outgoing calls at time (+4-15), the CC stops in the next cycle and reduces the call regulation level by 1.
hang down As a result, the call restriction level becomes 3.

(5) After that, such control is repeated, and when the abnormal light chain state is resolved, the call regulation level finally returns to 0.

Note that the call restriction level may be controlled not only by the usage rate of the CC as shown above, but also by the light chain status of various resources for exchange processing (memory block for call processing, call path, signal receiving device, etc.).

(Restriction processing for each call at each restriction level) Figure 5 shows the M used for restriction processing for each call in an embodiment of the present invention.
It shows the data in M16, 21 is a call number counter, 22 is a call restriction level pointer, 23 is a call restriction period pointer, and 24 is a call restriction table.

The number of calls counter 21 counts the number of calls, and is incremented by 1 every time a call is detected.
c) is cleared every time.

The call restriction level pointer 22 displays the current call restriction level i, and is controlled by the above-mentioned call restriction level control process every cycle T1.

The call regulation cycle pointer 23 is 1 of the T2X10 call regulation cycle.
1→2・j every period T2.
It is updated as →...→10→1→.

By referring to the call restriction table 24 using the call restriction level pointer 22 and the call restriction period pointer 23, it is possible to uniquely determine the number of calls allowed to be made in the period j.

The call restriction table 24 shows each call restriction cycle j for each restriction level i.
Data indicating the number of calls allowed to be made is described.

FIG. 6 is a flowchart showing the restriction processing for each call in one embodiment of the present invention. The processing for each call in the present invention will be explained below based on FIG. 6.

(1) Each time the system detects a call, it increments the call number counter by 1.

(2) Next, the system uses the restriction level pointer 22 and the restriction period pointer 25 to read the number of calls allowed to be made in the relevant period from the call restriction table 24.

For example, regulation level pointer tacho 3. Regulatory cycle pointer = 5
If so, only one call is allowed during the period (100m5ec').

(3) If the content of the number of calls counter 21 is equal to or less than the number of permissible calls in the cycle, the call is allowed to be made. However, if the content of the number of calls counter 24 exceeds the permissible number of calls, the call is prohibited from being called in that cycle, and is processed as a new call in the next cycle.

〔Effect of the invention〕

As explained above, according to the outgoing call restriction method of the present invention, the number of calls that can be detected within a certain period of time is adjusted according to the degree of load on the exchange. Call detection can also be continued, thereby improving service to subscribers. Furthermore, since excessive regulation is not performed in the event of abnormal congestion, the capacity of the switching equipment can be fully utilized.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the basic configuration of the present invention, Fig. 2 is a diagram showing the system configuration of an electronic exchange according to an embodiment of the present invention, and Fig. 3 is a diagram showing the call regulation for each cycle in an embodiment of the present invention. Flowchart showing level control processing; FIG. 4 is a diagram illustrating call restriction level control according to the present invention; FIG. 5 is a diagram showing data used for restriction processing for each call in an embodiment of the present invention; The figure is a flowchart showing restriction processing for each call in an embodiment of the present invention. 13...Subscriber circuit 14...Communication path (NW) 15...Processor (CC) 16...Memory (MM) 21...Call number counter 22...Call restriction level pointer 23. ...Call restriction cycle pointer 24...Call restriction table

Claims (1)

[Claims] Call restriction level determination in an electronic exchange, in which a determination is made in accordance with the load level of the exchange at predetermined intervals, and the call restriction level is increased or decreased as the high load level continues or disappears. Means (1
), and a call restriction table (2) that defines a permissible number of calls that changes depending on the level of the call restriction level, and the number of calls determined by the call restriction level determining means (1) is provided. call restriction processing means (3) for performing call restriction processing at predetermined intervals shorter than the predetermined period according to the number of permissible calls read from the call restriction table (2) in accordance with the call restriction level; A transmission regulation method characterized by the provision of.