JPS63309047A - Congestion control system by network control system - Google Patents

Abstract

PURPOSE:To shorten the time of recovery from a congestion state and to improve the processing efficiency of an exchange facing an exchange in a congestion state by determining an out-side route by referring to congestion information set in a memory corresponding to an exchange when receiving a call and determining the outside route. CONSTITUTION:If certain exchange EX enters a congestion state, a network control system MMS informs other exchanges EX of that and the respective exchanges EX update congestion information in their memories MM. At the time of determining an out-side route by receiving a call, each exchange EX refers to a memory MM in which is set congestion information showing whether or not its opposite exchange EX is in an congestion state, to determine its out-side route, and consequently a call is never sent out to the exchange in the congestion state. Consequently, the processing time of the exchange in the congestion state is shortened and the time of recovery from the congestion state can be shortened; and incomplete calls are reduced on the exchange side facing the congestion exchange and an unnecessary connection processing time is shortened, so the processing efficiency is improved.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a congestion control method that takes into consideration the entire switching network, and in particular, a method for controlling switching equipment connected to the switching network and forming the switching network.
Congestion control linked to a smart network management system
Regarding the n method.

[Conventional technology]

Conventionally, in a switching network that includes multiple exchanges, each exchange does not know whether the opposite exchange is congested or not. Sometimes calls are made to Therefore, in the conventional congestion control method for relieving congestion in a congested exchange, the congested exchange itself in the exchange network restricts incoming calls, and disconnects calls made by the opposite exchange. A method is adopted in which the own exchange reduces its own load and relieves congestion by returning the signal.

[Problem that the invention seeks to solve]

However, in the conventional system described above, even if a congested exchange restricts incoming calls, calls from the opposite exchange are added to the congested exchange, as described above.
A congested exchange must perform a process of returning a disconnection signal to a call added by the other exchange, and therefore there is a problem in that it takes time to relieve the congestion. Also,
Since the originating exchange also receives a disconnection signal from the congested exchange, there is a problem in that the number of incomplete calls increases and wasteful connection processing increases.

The present invention eliminates the above-mentioned problems, and its purpose is to shorten the recovery time from a congested state and to improve the processing efficiency of an exchange facing a congested exchange.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention provides a switching network equipped with a plurality of exchanges and a network management system that controls and monitors each of the exchanges. A memory is provided in which congestion information indicating whether or not an exchange facing the exchange is congested is set, and the network management system receives the ↑n from the exchange.
If it is determined that the exchange that is the source of the information is congested based on the information, information indicating that the exchange that is the source of the information is congested is sent to exchanges other than the exchange that is the source of the information. When each exchange receives information from the network management system indicating that one of the exchanges facing the own exchange is congested, the information is set in the memory corresponding to the own exchange. If the congestion information corresponding to the exchange Va that is notified of being congested in the congestion information is displayed as being congested, and the call is received and the outgoing route is determined, the congestion information is set in the memory corresponding to the own exchange. The outgoing route is determined by referring to the congestion information available.

[For production]

When an exchange becomes congested, the network management system notifies the other exchanges of this fact, and each exchange updates the congestion information in its memory.

Each sentence *a, when receiving a call and determining the outgoing route, refers to the memory in which congestion information indicating whether or not the opposing exchange is congested is set to determine the outgoing route. Therefore, calls are not sent to a congested switch.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the present invention, in which a packet switch I! constitutes a switching network. XI to EX4 are connected to each packet exchanger Ex1 to EX4, and each packet exchange i
A network management system XMS that controls and monitors EX1-EX4 and a subscriber terminal 5UBI.

5UB2. Packet switch EXI and packet switch ml! It is connected to X2 by communication route LN12, and packet exchanger EXI and packet exchanger EX3
are connected by communication route LN13, and packet exchange EX2 and packet exchange EX3 are connected by communication route 1, N
23 and packet exchanged al! X2 and the packet switch EX4 are connected by a communication route LN24, and the packet switch EX3 and the packet switch 811BX
4 is a communication route) It is connected by LN34. Also, each packet exchange 1a [! X 1 ~ [! Congestion information I!x4 indicates whether the opposing packet exchange tX machine is congested or not. It is provided with memory questions 1 to MM4 in which a value (in this embodiment, "1" indicates congestion and "0" indicates normality) is set.

In addition, FIGS. 2 and 3 show packet exchanges Ex1 to [X4
1 is a flowchart showing an example of processing, and the operation of this embodiment will be described below with reference to each figure.

Each of the packet exchanges EXI to EX4 in the switching network periodically performs the process shown in the flowchart of FIG. 2, that is, collects traffic information (for example, the usage rate of the internal CPU) (step 521), and collects the collected traffic. Send information to network management system NMS (step 522)
) processing.

The network management system NMS is for each bucket and exchanger E.
If the packet switch that sent the traffic information is determined to be in a congested state based on the traffic information sent from χ1 to EX4, the congestion detection information ( If it is determined that the congestion state has returned to normal, it sends congestion release information (including information indicating that congestion has occurred and the exchange name of the packet switch where congestion occurred) to other packet switches (including information indicating that congestion has occurred). (including information indicating that the packet switch has been released and the switch name of the packet switch).

Note that the determination of whether or not a congestion state has occurred is not made by the network management system NMS, but by each packet exchanger EX1-F!
It may be done with χ4, or each bucket/throat exchanger EX
If I to EX4 are configured to determine whether or not a state of congestion has occurred, instead of sending traffic information periodically, the packet switch will send a notification to that effect at the time it determines that it has become congested. network management system
The MS may be notified.

Each packet switch [! When congestion detection information is added from the network management system ltMs, XI to BX4 first determine whether the same exchange rename included in the added congestion detection information is set in the memories MMI to MM4. , if it is determined that it has been set, the congestion information corresponding to the exchange rename included in the congestion detection information is set to “1”.
". Also, when congestion release information is added, each packet exchange EX1 to EX4 determines whether the exchange rename included in the added congestion release information is set in memory questions 1 to -1114. However, if it is determined that it has been set, the corresponding congestion information is set to "0".

For example, if the packet exchange EX2 becomes congested, then the packet exchange EX1. EX3. [! X4
The network management system NMS was exchanged and renamed EX
2 is added to each packet exchanger E.
X1. [! X3. ! ! When the above-mentioned congestion detection information is added to X4, the exchange name change EX2 included in the above-mentioned congestion pass side exit information
is memory MMI, MM3. In this embodiment, the memory MAIL,
MM3. A bucket equipped with MM4!・Exchange machine EX
1. EX3. EX4 is a congested bag/I□Exchange E
X2, and the exchange name of the opposite packet switch is set in the memory, so each bucket exchange IaEXI, EX3. EX4 sets the congestion information corresponding to the exchange name change EX2 to "1", indicating that the packet exchange EX2 is congested.

Next, the state described above, ie, memory M? 11. The operation when the subscriber terminal 5tlB1 makes a call to the subscriber terminal 5UB2 in a state where the packet exchanger EX2 is displaying congestion on the MM 3/4 will be explained.

Bucket switch E housing subscriber terminal 5UBI
When XI detects a call from subscriber terminal 5IIBI,
The processing shown in the flowchart in the figure is performed. First, the packet switch EXI sets the outgoing route to communication route LN12 or communication route 1-LN13 based on the communication partner number included in the call from subscriber terminal 5UBI and a predetermined priority +11I. In step 531, flag F is set to "1" (step 532).
12, packet switch E
XI is exit route +1. Bucket intersection 14 corresponding to N12
Ql[! X2 is determined (step 533), and then it is determined whether the packet exchange EX2 is busy or not based on the contents of the last MMI (step 534).

In this case, since the memory 11 displays that the packet exchange EX2 is congested, the determination result in step S34 is Yl! S, and the packet exchanger IEXI performs the process of step S35.

In step S35, the packet switch l! XI checks whether a detour exists or not, and if it determines that there is no detour, it sends a busy message to the subscriber terminal 5IIBI (step 541). Further, if it is determined that there is a detour route, the packet switch εχ1 sets the communication route with the next highest priority as the outgoing route (Step 336), then sets the flag F to "0" (Step 537), and then proceeds to Step S33. Return to processing.

In this embodiment, the communication route LNI is used as a detour route.
3 exists, the determination result in step S35 is YES.
So, bucket exchanger 1! Xi is communication route) LN13
is set as the exit route (step 336), and then the process returns to step S33.

In step S36, the output route is set as the communication route LN1.
3, the packet switch EXI finds a packet switch Ex3 corresponding to the communication route LN13 (
Step 533) Check whether the packet switch EX3 is congested or not in the memory M? Judgment will be made based on the contents of 11 (
Step 534). In this case, bucket exchange JIaEX
3 is not congested, the determination result in step S34 is NO, and the packet exchange tBiEX l has flag F set to "
Step 838)
. In this case, since the flag F is set to "0" in step S37, the packet switch EX1 sends the call to the communication route LN13, which is set as the egress route in step S36 (step 540), and then performs other control steps. If the determination result in step 38 is YES, the packet switch F! , x1 is for sending a call to the communication route set as the outgoing route in step S31 (step 539).

Bucket exchange 1EX3. Bucket exchange also in EX4
AiI! The same process as in X1 is performed, and the bucket exchanger EXI-communication route LN13-packet exchanger 1'!
X3 - On communication route N34 - Subscriber terminal 5UBI and subscriber terminal 5UB2 are connected via packet exchange EX4.

That is, the congested bucket exchange iEX 2 is bypassed,
The route is determined without any connection failure on the way, and the subscriber terminal 5UBI and the subscriber terminal 5UBI enter a communication state.

In the above-described embodiment, the network management system NMS sends congestion detection information to all packet exchanges other than the bucket exchange that has become congested. It is also possible to send the information only to the packet switch facing the switch.

〔Effect of the invention〕

As explained above, the present invention provides a memory in which congestion information indicating whether or not the opposite exchange is congested is set for each exchange in a switching network, and each exchange receives and outputs a call. When determining the outgoing route, the outgoing route is determined by referring to memory, so calls are no longer sent to a congested exchange, which reduces the processing time of the congested exchange. This has the effect of shortening the recovery time from a congestion state compared to the conventional example, and also reduces incomplete calls on the side of the exchange facing the congested exchange, reducing wasted connection processing time. It becomes possible to process other normal calls accordingly, which has the effect of improving processing efficiency.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIGS. 2 and 3 are flowcharts showing processing examples of a packet switch. In the figure, NMS...network management system,
EXI~EX4...Packet switch, question 1~question 4...
・Memory, LN12. LN13. LN23. LN
24. LN34...Communication route, 5UBI, 5U
B2...Subscriber terminal.

Claims (1)

[Scope of Claims] In a switching network including a plurality of exchanges and a network management system that controls and monitors each exchange, each of the exchanges is provided with information on whether the exchange opposite to the own exchange is congested or not. a memory is provided in which congestion information is set indicating whether the network management system is congested; Notifying exchanges other than the exchange of information indicating that the exchange that is the source of the information is congested, and each of the exchanges receives information from the network management system indicating that one of the exchanges facing the own exchange is congested. If information indicating that the call is congested is notified, the congestion information set in the memory corresponding to the own exchange and corresponding to the exchange notified of being congested is displayed as congested, and the call is not received. A congestion control method using a network management system, characterized in that when an outgoing route is determined based on congestion information set in the memory corresponding to the own exchange.