JPH06261061A - Congestion elimination control system for atm communications network - Google Patents

Abstract

PURPOSE:To obtain the congestion elimination control system for an ATM communications network in which traffic of undesired connection is restricted so as to eliminate congestion by referencing connection information when the congestion takes place in an ATM exchange. CONSTITUTION:When congestion takes place in ATM exchanges 1, 2, 3 in an ATM communications network alpha, a network management equipment 4 receiving the notice of occurrence of the congestion via logic communication-5' circuits 9, 10, 11 references connection attribute information stored in a connection attribute table 5 provided to the network management equipment 4. Then any of connection sets A-D set in a management area beta of the network management equipment 4 is selected corresponding to the referenced connection attribute information and gives a command of abort of part or all of the connection sets A-D selected through logic communications circuits 9, 10, 11 to the ATM exchanges 1, 2, 3 via the selected connection sets A-D. Thus, the traffic of the connection sets A-D is restricted to eliminate the congestion caused in the ATM exchanges 1, 2, 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a congestion elimination control for notifying the occurrence of congestion and restricting the traffic when traffic exceeding the transmission capacity of the network is input in the ATM communication network and congestion occurs in the ATM switch. It is related to the method.

[0002]

2. Description of the Related Art In a conventional ATM communication network, if congestion occurs in an ATM switch due to the input of traffic exceeding the transfer capacity of the network, the communication quality may be deteriorated. Connection admission control method and UPC (UsageParameter C
The control method and the like have been proposed.

In the above UPC system, a CLP (Cell Loss Priorit) in a cell header is used.
y) A reactive control method has also been proposed in which a flag is set in the bit and when congestion occurs in the ATM switch, the congestion caused by discarding the cell violating the user-reported value in the ATM switch is eliminated. .

[0004]

However, the above-mentioned connection admission control system and UPC system cannot completely prevent the occurrence of congestion in the ATM switching system, and the reactive control system does not cause congestion in the ATM switching system. If it occurs, it is possible to quickly resolve congestion, but VIP
In an ATM communication network in which connections with different degrees of importance exist in the same network, such as general-purpose telephones and general-purpose telephones, traffic restrictions are uniformly applied to connections with different degrees of importance, regardless of the degree of importance. Since it is carried out, there is a drawback that highly important connections cannot be excluded from the traffic regulation targets and may be discarded in the ATM exchange.

In view of the above-mentioned problems of the prior art, the present invention refers to connection attribute information such as connection importance and connection route when congestion occurs in the ATM switch, and the connection selected in accordance with the connection attribute information. The traffic of the connection is regulated by discarding part or all of the cell or disconnecting the connection.
It is an object of the present invention to provide a congestion elimination control method in an ATM communication network for eliminating congestion in a TM exchange.

[0006]

The solution to the above-mentioned problems can be achieved by adopting the novel characteristic construction methods enumerated below by the present invention. That is, a first feature of the present invention is that in an ATM communication network in which one or more ATM exchanges are connected by physical communication circuits, a network management device that manages the ATM exchanges through a logical communication circuit and the inside of the ATM exchanges are provided. Means for detecting congestion that has occurred, means for notifying the network management device that congestion has occurred in the ATM switch through the logical communication circuit, and each connection set in the management area of the network management device. Means for holding connection attribute information including connection importance and connection route relating to the network management device, and when congestion occurs in the ATM switch, the network management device that has been notified of the occurrence of congestion is held in the holding means. Is set in the management area corresponding to the referred connection attribute information. Note that by selecting one of the connections and instructing the logical communication circuit to discard some or all of the cells of the selected connection, the traffic of the connection is regulated and generated in the ATM switch. It is a congestion elimination control method in an ATM communication network that eliminates the congestion.

A second feature of the present invention is an ATM communication network in which the network management device in the first feature refers to at least two types of information of connection importance information and connection route among the held connection attribute information. This is a congestion resolution control method.

A third feature of the present invention is that the network management device according to the first or second feature selects only a connection of low importance among the referred connection attribute information and selects a cell of the connection of low importance. Is a congestion elimination control method in an ATM communication network instructing to discard some or all of the above.

A fourth feature of the present invention is that the network management device according to the first, second or third feature forces a selected connection to an ATM switch through which the connection passes through a logical communication circuit. It is a congestion resolution control method in an ATM exchange in which a disconnection instruction is issued.

[0010]

Since the present invention has taken the above-mentioned method,
Even if congestion occurs in the TM switch, the connection management, connection route, etc. can be referred to by the network management device, so the connection importance can be confirmed, and traffic restrictions can be selectively applied to less important connections. The congestion in the ATM exchange can be eliminated.

More specifically, means for holding connection attribute information including connection importance and connection route regarding each connection set in the management area of the network management device is provided in the ATM communication network, and when congestion occurs, notification of congestion occurrence is given. The network management device having received the information controls the connection attribute information held in the holding means at least with reference to the connection importance and the connection route, and regulates the traffic of some of the connections set in the management area.

That is, when the load on the ATM exchange becomes large and congestion occurs, the ATM exchange notifies the network management device that manages the ATM exchange that congestion has occurred. The network management device refers to the connection attribute information and seeks a connection of low importance among the connections passing through the congested ATM exchange,
Restrict traffic on some or all of these connections. This reduces the load on the congested exchange.

[0013]

Embodiments of the present invention will be described in detail with reference to the drawings. Figure 1
Is a block diagram showing an ATM communication network to which the congestion resolution control system of this embodiment is applied, and FIG. 2 is a table showing a configuration example of the connection attribute information holding means in FIG.

In the figure, α is an ATM communication network, β is a management area, 1, 2 and 3 are ATM switches, 4 is a network management device, 5 is a connection attribute table holding connection attribute information, and 5a is a connection identifier storage. Field, 5b
Is a connection path storage field, 5c is a connection importance level storage field, 6, 7 and 8 are physical communication circuits for mutually connecting ATM exchanges 1, 2 and 3, respectively.
9, 10, and 11 are the network management device 4 and the ATM exchanges 1, 2, and
3 is a logical communication circuit for connecting to each.

The execution procedure of the embodiment will be described with reference to the drawings. (Execution 1) First, in FIG. 1, when the load in the ATM switch 1 becomes large and congestion occurs, the network management apparatus 4 is notified of the occurrence of congestion through the logical communication circuit 9, and the connection attribute information is held in advance. Refer to the connection attribute table 5.

The network management device 4 refers to the connection attribute table 5 shown in FIG. 2 and searches the connection route storage field 5b to find the ATM switch 1 in which congestion has occurred.
Select the connection that goes through the connection and select connection A and connection B from the connection identifier storage field 5a.
To get

Next, a connection importance storage field 5
The connection importance storage field 5 is searched by selecting c and selecting the connection having the connection importance of “non-importance” from the connection A and the connection B obtained from the connection identifier storage field 5a in the above.
Get connection A from c.

The network management device 4 which has obtained the connection A forces some or all of the cells of the connection A to the ATM switch 1 and the ATM switch 2 through which the connection A passes through the logical communication circuits 9 and 10. Instruct to discard or disconnect connection A. As a result, the traffic of the connection A that has passed through the ATM switch 1 is restricted, the load in the ATM switch 1 is reduced, and the congestion is eliminated.

(Execution 2) When the load is increased in the ATM exchange 2 and the ATM exchange 3 shown in FIG. 1 and congestion occurs in both the ATM exchanges 2 and 3, first, the logical communication circuits 10 and 11 are executed. The network management device 4 is notified of the occurrence of congestion in the ATM exchanges 2 and 3 through the connection, and the connection attribute table 5 holds the connection attribute information.

The network management device 4 refers to the connection attribute table 5 shown in FIG. 2 and searches the connection route storage field 5b to cause congestion in the ATM switches 2 and 3.
A connection passing through both of these is selected from the connection identifier storage field 5a to obtain the connection C and the connection D.

Next, the connection importance storage field 5
c is searched, and the connection having the connection importance of "non-important" is selected from the connections C and D obtained from the connection identifier storage field 5a in the above, and the connection D is obtained from the connection importance storage field 5c.

The network management device 4 which has obtained the connection D transmits the connection D to both the ATM exchanges 2 and 3 through which the connection D passes through the logical communication circuits 10 and 11.
Instructing to forcibly discard some or all of the cells of the above, or forcibly disconnecting the connection D.

As a result, the traffic of the connection D that has passed through both the ATM exchanges 2 and 3 is restricted,
The load on both the ATM switches 2 and 3 is reduced, and congestion is eliminated. The connection attribute information including the connection importance and the connection route regarding each of the connections A to D set in the management area β of the network management device 4 is appropriately changed according to the change of the setting status of the connections A to D. Will be updated.

In this embodiment, when the network management device 4 refers to the connection attribute information, it uses two types of information, the connection route and the connection importance, but other connection attribute information (for example, the media type of the connection). And user-reported traffic) can be used together, and the connection importance is also displayed in two stages of “important” and “non-important” in the present embodiment, but more stages (eg, importance) It is also possible to display in 10 steps from 1 to 10) and to make the target range of the connection selected to regulate traffic when congestion occurs differ depending on the degree of congestion.

Further, in this embodiment, the connection attribute table 5 is held in the network management device 4, but this is AT
A place in the M communication network α (for example, ATM exchanges 1, 2, 3
Inside), and when controlling traffic, ATM is transmitted from the network management device 4 through the logical communication circuits 9, 10 and 11.
I issued instructions to the exchanges 1, 2 and 3, but ATM
It is also possible to instruct the connection setting function unit (not shown) in the communication network to forcibly disconnect the selected connection and regulate the traffic.

[0026]

As described above, according to the present invention, the connection information can be confirmed even if congestion occurs in the ATM switch, so that the traffic control can be performed only for unnecessary or less important connections. It has excellent practicability such as eliminating congestion without restricting the traffic of important connections quickly, reducing the call loss rate of important connections, and preventing deterioration of communication quality.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an ATM communication network to which a congestion resolution control system according to an embodiment of the present invention is applied.

FIG. 2 is a table showing a configuration of means for holding connection attribute information in the above.

[Explanation of symbols]

 α ... ATM communication network β ... Management area 1, 2, 3 ... ATM switch 4 ... Network management device 5 ... Connection attribute table 5a ... Connection identifier storage field 5b ... Connection route storage field 5c ... Connection importance storage field 6, 7, 8 ... Physical communication circuit 9, 10, 11 ... Logical communication circuit

Claims (4)

[Claims] 1. An ATM communication network in which one or more ATM exchanges are connected to each other through a physical communication circuit, and a network management device for managing the ATM exchanges through a logical communication circuit and a congestion occurring in the ATM exchange are detected. Means, means for notifying the network management device that congestion has occurred in the ATM switch through the logical communication circuit, and connection importance and connection for each connection set in the management area of the network management device. Means for holding connection attribute information including a route,
When congestion occurs in the M switch, the network management device, which has received the notification of the congestion occurrence, refers to the connection attribute information held in the holding means, and manages the management in accordance with the referred connection attribute information. A part or all of cells of the selected connection are selected through the logical communication circuit to the ATM switch through which the selected connection passes by selecting one of the respective connections set in the area. Traffic is controlled by instructing that the AT be discarded.
A congestion elimination control method in an ATM communication network, which is characterized by eliminating congestion occurring in an M switch. 2. The congestion resolution control method in an ATM communication network according to claim 1, wherein the network management device refers to at least two types of information of connection importance and connection route among the held connection attribute information. . 3. The network management device selects only a connection with low importance from the referred connection attribute information and instructs to discard some or all of the cells of the connection with low importance. The congestion resolution control method in an ATM communication network according to claim 1 or 2. 4. The network management device instructs the ATM exchange through which the selected connection is forcibly disconnected through a logical communication circuit, through the logical communication circuit. A congestion resolution control method in the ATM exchange described.