JPH05304536A - Congestion discrimination system in asynchronous transfer mode - Google Patents

Abstract

PURPOSE:To detect the congestion state by setting a congestion criterion of an ATM switch and an ATM relay line flexibly in response to a state of a station. CONSTITUTION:An ATM cell abort monitor measurement circuit (DC) 4 is provided with an ATM cell abort reference memory (MEM) 6 to store a cell abort reference number per predetermined unit time and an ATM cell abort counter (CNT) 5 counting number of cells aborted by an ATM cell exchange switch (ATM SW) 8 and an ATM network interface circuit (I/F) 7. When the DC 4 detects it that the cell abort number counted by the CNT 5 exceeds a cell abort reference number stored in the MEM 6, it is informed to a CPU 9 as a congestion state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a storage program control type electronic exchange having an ATM (asynchronous transfer mode) switch and an interface with an ATM network, and more particularly to a congestion judgment method in an ATM switch or an ATM interface circuit.

[0002]

2. Description of the Related Art Conventionally, in a congestion determination method in an asynchronous transfer mode of an exchange having an ATM switch and an interface with an ATM network, when an ATM cell discard monitor / measurement circuit provided in this exchange detects the discard of an ATM cell. By raising this information to the central processing unit of the exchange,
The central processing unit has determined that the ATM switch or ATM network interface is congested.

[0003]

In this conventional congestion determination method in the asynchronous transfer mode, since congestion is detected even when one ATM cell is discarded, all instantaneous congestion is raised to the central processing unit. As a result, there is a problem that the congestion alarm is frequently displayed even though the congestion is subsided.

[0004]

The congestion determination method in the asynchronous transfer mode according to the present invention comprises a converter for converting voice / data information into a cell in the asynchronous transfer mode or a converter for restoring this cell into voice / data information, and the cell. ATM to exchange
In a storage program control type exchange having a switch, an ATM network, an interface circuit for transmitting and receiving the cell, and a measuring circuit for monitoring the discarding of the cell, the measuring circuit is provided with cells per a predetermined unit time. A memory for storing the discard standard number and a counter for counting the number of cells discarded by the ATM switch and the interface circuit per unit time are provided, and the number of cell discards per unit time is predetermined. When the measurement circuit detects that the number of cell discard standards is exceeded,
This is a configuration for notifying the central processing unit of the exchange as a congestion state.

[0005]

The present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing the configuration of a storage program controlled ATM (asynchronous transfer mode) switch for explaining an embodiment of the present invention. In FIG. 1, TE1 is a voice or data terminal, LC2 is a line circuit to which the TE1 is connected, CLAD3 is a voice or data information from the TE1, and an ATM cell for restoring the cellized voice or data information. Conversion / restoration circuit, DC4 is ATM
ATM cell discard monitor / measurement circuit for monitoring and measuring cell discard in a switch or ATM network interface circuit, C
NT5 is an ATM cell discard counter for counting and storing the number of discarded cells, MEM6 is an ATM cell discard reference memory for storing the number of cell discard standards input from the maintenance terminal, and I / F7 is for transmitting / receiving cells to / from the ATM network. Interface circuit to perform, ATM SW8 is an asynchronous transfer mode switch, CPU9 is a central processing unit, MAT10 is a maintenance terminal, C-BUS11 is a command from the central processing unit 9 to the line circuit 2, ATM cell discard monitoring measurement circuit 4, and interface circuit 7. Control bus for sending an event or raising an event from these circuits to the central processing unit 9, AL
INE12 is an ATM trunk line.

The maintenance operator of the switchboard inputs the ATM cell discard standard number per unit time in the ATM SW 8 or I / F 7 from the MAT 10 in advance. The input data is ME in DC4 via CPU9 and C-BUS11.
It is set to M6.

The voice or data information after the TE1 and the terminal outside the station are in the communication state is made into cells by the CLAD3 via the LC2, switched by the ATM SW8 and switched by the I / F.
It is sent to A-LINE 12 via 7.

When the ATM SW8 is congested during the exchange of ATM cells for other call processing, the ATM cells from the TE1 are discarded by the ATM SW8. Similarly, A at the end of I / F7
-AT from TE1 if LINE12 is congested
The M cell is discarded at I / F7. DC4 is ATM S
When ATM cell discard in W8 and I / F7 is monitored and discard occurs, the count of CNT5 is incremented by 1 and the value is compared with the value of MEM6.

If the value of CNT5 is larger than the value of MEM6, the central processing unit 9 is notified via the C-BUS 11 that the number of discarded cells has reached the reference value. When the value of CNT5 is smaller than the value of MEM6, DC4 continues to be ATM
The cell discard of SW8 or I / F7 is monitored. Incidentally, D
C4 clears CNT5 at regular time intervals to count the number of cell discards per unit time, and then starts counting.

[0011]

As described above, according to the present invention, the predetermined number of discarding ATM cells per unit time is set in the memory in the measuring circuit, and the number of discarding ATM cells counted by the counter in the measuring circuit is set. In comparison with the above, since the congestion in the asynchronous transfer mode is notified to the central processing unit when the number of discarded ATMs exceeds the reference number, there is an effect that the congestion determination standard can be flexibly set and the congestion can be detected depending on the local condition.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an ATM switch for explaining an embodiment of the present invention.

[Explanation of symbols]

 1 terminal (TE) 2 line circuit (LC) 3 ATM cell conversion / restoration circuit (CLAD) 4 ATM cell discard monitor and measurement circuit (DC) 5 ATM cell discard counter (CNT) 6 ATM cell discard reference memory (MEM) 7 ATM network interface circuit (I / F) 8 ATM cell exchange switch (ATM SW) 9 Central processing unit (CPU) 10 Maintenance terminal (MAT) 11 Control bus (C-BUS) 12 ATM relay line (A / LINE) )

Claims (1)

[Claims] 1. A converter for converting voice / data information into cells in an asynchronous transfer mode or for restoring the cells into voice / data information, and an ATM switch for exchanging the cells.
In a storage program control type exchange having an ATM network, an interface circuit for transmitting and receiving the cell, and a measuring circuit for monitoring the discard of the cell, the measuring circuit includes:
A memory for storing a predetermined cell discard standard number per unit time and a counter for counting the number of cells discarded by the ATM switch and the interface circuit per unit time are provided, and When the measurement circuit detects that the number of cell discards exceeds a predetermined number of cell discards, the congestion determination method in the asynchronous transfer mode is notified to the central processing unit of the exchange as a congestion state. ..