JP2785147B2 - Restriction method for each route - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Overview] In a packet communication network composed of a plurality of terminals and a packet switching node accommodating them and a transmission line coupling between the packet switching nodes, congestion of nodes and transmission lines Concerning the packet transfer regulation method that alleviates the state, the purpose is to enable only a communication path passing through a transmission path causing congestion to be controlled by simple control processing, and to enable quick recovery from a congestion state In each packet switching node, for each transmission path in the packet communication network, each communication path from any terminal accommodation unit of any packet switching node to any terminal accommodation unit of any other packet switching node Communication path storage means for storing which communication path is included in the communication path and transmission paths accommodated in the own packet switching node Congestion state detection means for detecting a state, congestion state notification means for notifying another packet switching node of the congestion state of the transmission path detected by the congestion state detection means as congestion state notification, The congestion state notification is received, and a communication path included in the transmission path corresponding to the congestion state notification is searched from the communication path storage unit, and the searched communication path is included in the transmission path accommodated by the own packet switching node. Communication path discriminating means for discriminating a communication path in use, and communication path control means for controlling transmission of packet data transferred on the communication path discriminated by the communication path discriminating means based on a congestion state notification. To be configured.

[Industrial applications]

The present invention relates to a packet transfer for reducing a congestion state of a node and a transmission line in a packet communication network including a plurality of terminals and a transmission line connecting the packet switching nodes accommodating them and between the packet switching nodes. Regarding the regulation system.

[Conventional technology]

The packet communication network is configured by a transmission path connecting between terminals and packet switching nodes accommodating them and between packet switching nodes. The terminal is a source of various types of information such as data, images, and sounds. The packet switching node extracts superiority information included in the packet from the terminal and creates a packet format by adding a new destination address to the head of the superiority information, or determines the destination route. And so on.

In a packet communication network, a packet switching node extracts necessary information stochastically generated from a terminal and communicates it as packet data. As a result, in the network, highly efficient resource management due to a large grouping effect is realized. ing. In this case, each packet is temporarily buffered in a transfer waiting buffer in the node, and is controlled so that the bandwidth of the transmission path becomes constant.

However, when attempting to perform synchronous communication or the like that requires real-time performance using packets, the information generated from the terminal is irregular, so if each information is multiplexed on the line, a low probability It can happen that packets concentrate on the switching node. As a result, the packet transfer processing in the node cannot be performed, and the transmission delay of the communication packet in the node increases. If the number of packets remaining in the transfer waiting buffer exceeds the permissible limit, a problem arises in which congestion occurs, packets are discarded, and communication quality is degraded.

In order to solve the congestion problem in the packet communication network as described above, an input restriction method for notifying from a node in which congestion has occurred (hereinafter, referred to as a congestion node) so as to temporarily stop a transfer source of a transfer packet. Is generally adopted.

As a first conventional example of the input control method, a congestion node simultaneously notifies all other stations, and in response to this, each station determines whether or not it currently has a communication path passing through the congestion node. If it is determined that the communication path is held, there is a method of restricting the transfer of the packet to the congested node.

As a second conventional example of the input restriction method, there is a method in which a congestion node selects a restriction notification for a communication path passing through the congestion node and stops only the communication source of the path.

[Problems to be solved by the invention]

However, in the case of the above-mentioned first conventional example, since a regulation notification is issued to all stations, there is a high possibility that the packet congestion state will spread to other stations, and there is a problem that the effect of reducing the congestion is small. doing.

Further, in the case of the above-mentioned second conventional example, it is necessary to manage a reverse path of the communication path, and furthermore, it is necessary to perform the management for each type of communication data. There is a problem that the transfer of the notification is delayed and the buffer amount until the effect of the regulation control becomes enormous.

SUMMARY OF THE INVENTION It is an object of the present invention to enable only a communication path passing through a transmission path causing congestion to be restricted by a simple control process, and to enable quick recovery from a congestion state.

[Means for solving the problem]

FIG. 1 is a block diagram of the present invention. The present invention is premised on a packet communication network composed of a plurality of terminals and packet transmission nodes accommodating them, and a transmission line connecting between the packet switching nodes. Each of the packet switching nodes has the following configuration.

First, for each transmission path 106 in the packet communication network, which communication path among the communication paths from an arbitrary terminal accommodation section of an arbitrary packet switching node to an arbitrary terminal accommodation section of another arbitrary packet switching node is It has a communication path storage means 101 for storing whether or not it is included.

Next, the transmission path 106 accommodated in the own packet switching node
And a congestion state detecting means 102 for detecting the congestion state.
The means detects, for example, either occurrence of a congestion state of the transmission path 106 accommodated in the own packet switching node or elimination of the congestion state. In addition, you may comprise so that an intermediate congestion state can be detected.

Next, the transmission line 10 detected by the congestion state detecting means
There is a congestion state notifying means 103 for notifying another congestion state to another packet switching node as a congestion state notification 107. In this case, the congestion state notification 107 occurs, for example, in the congestion state occurrence notification indicating that a congestion state has occurred in the transmission line 106 accommodated in the own packet switching node and in the transmission line 106 accommodated in the own packet switching node. This is one of the congestion state elimination notifications indicating that the congested state has been resolved. In addition, you may comprise so that an intermediate | middle congestion state can be notified.

Further, a congestion state notification 10 from another packet switching node
7, the communication path included in the transmission path corresponding to the congestion state notification is searched from the communication path storage unit 101, and the communication path included in the transmission path 106 accommodated by the own packet switching node among the searched communication paths. Communication path determining means 104 for determining the communication path being used.

The communication path control unit 105 controls transmission of the packet data 108 transferred on the communication path determined by the communication path determination unit based on the congestion state notification 107. This means, for example, when a congestion state occurrence notification is received from another packet switching node,
4 restricts the transmission of the packet data 108 transferred on the communication path determined by the communication path, and when a congestion state elimination notification is received from another packet switching node, the restriction on the communication path determined by the communication path Cancel. It should be noted that the transmission amount of the packet data may be controlled stepwise based on the notification indicating the intermediate congestion state.

In the above configuration, for each transmission path accommodated in the own packet switching node, transmission waiting buffer means for holding packet data to be transmitted to the own transmission path, and packet data to be restricted from being transmitted to the own transmission path. And a restriction waiting buffer means for holding And
In this case, the above-mentioned congestion state detecting means 102 is provided for each transmission line 106 accommodated in the above-mentioned own packet switching node, and monitors the amount of accumulated packet data in the transmission waiting buffer means, thereby achieving the above-mentioned congestion. It can be configured to detect either occurrence of a state or resolution of a congested state. Further, the above-mentioned communication path control means 105 is provided for each transmission path 106 accommodated in the above-mentioned own packet switching node, and can be constituted by the following means. That is, first, information indicating whether or not packet data transmission is currently restricted for each communication path included in the own transmission path is stored, and when a congestion state occurrence notification is received from another packet switching node, Communication path determination means 104
Information indicating that regulation is being performed on the communication path determined by the communication path determination unit 104, and when a congestion state elimination notification is received from another packet switching node, Set information indicating that the regulation on has been released. It has a regulated route setting storage means. Also, packet data 108 to be transmitted
Communication path extracting means for extracting the communication path of (1). Further, it is detected from the regulated route setting storage means whether or not the communication route extracted by the communication route extracting device is regulated. If the regulation is performed, the packet data 108 to be transmitted is Is held in the buffer waiting for regulation, and when the regulation is not performed, there is selector means for holding the packet data 108 to be transmitted in the buffer waiting for transmission. Then, upon receiving a congestion state elimination notification from another packet switching node, the packet data held in the restriction waiting buffer means is transmitted to its own transmission path,
In other cases, there is provided a gate unit for transmitting the packet data held in the transmission waiting buffer unit to its own transmission path.

[Action]

For example, when congestion occurs in a certain packet switching node or a transmission line accommodated by the node, the information is notified to another packet switching node as a congestion state notification 107. In this case, the notification is made in the form of a transmission path number and the like and a flag indicating the occurrence of a congestion state.

In the other packet switching nodes that have received the notification, the communication path included in the transmission path corresponding to the congestion state notification 107 is searched from the communication path storage unit 101, and the own packet switching node among the searched communication paths is The communication path included in the transmission path 106 to be accommodated is determined, and transmission of the packet data 108 transferred through the determined communication path is controlled based on the congestion state notification 107.

As a result, packet data on a communication path toward a transmission path in which congestion or the like has occurred can be quickly regulated for each packet switching node, and congestion such as congestion can be quickly eliminated.

In this case, in each packet switching node, the transmission path
At 106, only the packet data of the communication path toward the transmission path where the congestion or the like has occurred is restricted, and the packet data of the other communication paths are not regulated and are transferred as usual. Therefore, it is possible to minimize the spread of a congestion state such as congestion to another.

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

FIG. 2 is an overall configuration diagram of the packet communication network. In the example of FIG.
Is a packet switching node (hereinafter simply referred to as a node) 20
2 _A , 202 _B , 202 _C and 202 _D are transmission lines 203 _AB , 203 _AD , 203
It has a configuration in which they are interconnected by _BC , 203 _BD , 203 _{DC and the} like. Then, in the example node 202 _A, a plurality of terminals 204 _A1 to 204 _An etc. of various kinds are housed. Similarly node 20
_2B to the terminal 204 _B1 , and the node 202 _C to the terminal 204 _C1 .
In addition to 204 _Cm, a private branch exchange PBX 206 _C that accommodates extension terminals 207 _{C1 to} 207 _{Ck and the} like are accommodated. Furthermore, the node 202 _D is, for example terminal 20 _D1, the host computer 205 _D and the like are accommodated. The network configuration shown in FIG. 2 is an example, and a larger-scale network can be actually constructed.

Next, FIG. 3 is a block diagram showing a configuration of a third diagram of a node 202 _A, 202 _B, 202 _C and 202 _D. In the following description, the node 202 _{A and the} like are simply called the node 202, and the transmission path 203 _AB
Etc. are simply referred to as transmission path 203, and terminal 204 _A1 etc.
Call.

As shown in the figure, the terminal 204 is accommodated in a packet assembling / disassembling unit 302, and the transmission path 203 is accommodated in a transmission path accommodation unit 301. Packet assembling / disassembling unit 302 or transmission path accommodation unit 301
Is converted into packet data of a common protocol that does not depend on the type of communication medium, and then input to the transfer destination determining unit 303. The determination unit determines the destination information added to the packet header, adds new destination information to the packet data, and
306. The disassembly unit 304 is used for the packet highway 30
The communication data on 6 is selected and transmitted by the transmission path accommodation unit 301.

The control processor 305 performs control such as call control and network monitoring while controlling the transfer destination determination unit 303 and the like. Further, a path line of a regulation notification described later is determined with reference to the path information table TBL1 stored in the path information table storage unit 306. Then, various types of control data are exchanged between the transmission path accommodating unit 301 and the packet assembling / disassembling unit 302 via the control bus 308. Further, control data is transmitted and received between the other nodes 202 from the common line signal unit 307 via the common line 309.

Next, FIG. 4 is a diagram showing the configuration of an embodiment of the transmission accommodating unit 301 of FIG. 3 according to the present invention.

For the packet data input from the packet highway 306 of FIG. 3 to the input / output unit 401 via the distribution unit 304, first, the path number extraction unit 402 extracts the path number 411 of the communication path through which the packet data is transmitted. After
The transmission path encoding unit 403 converts the data into a protocol suitable for the type of the communication medium.

The regulated route table storage unit 404 stores a regulated route table TBL2 to be described later.
It is set via the control bus 308 by the control processor 305 in the figure. The same table is stored in the path number extraction unit 402
Is accessed using the path number 411 extracted in the above as an address. As a result, the regulated route flag 413 is output from the regulated route table storage unit 404 to the selector 405. selector
405 is a transmission path encoding unit based on the regulation path flag 412.
The packet data converted in 403 is passed to the passage route queue of the passage route waiting buffer 407 or the regulation route waiting buffer 406.
Selectively connect to the restricted route queue.

The gate control unit 409 normally selects the output of the passage route waiting buffer 407 by controlling the gate 410, and the packet data connected to the passage route queue of the buffer is
The data is sequentially transmitted to the transmission path 203 via the gate 410.

Further, the gate control unit 409 is provided for the control processor 3 shown in FIG.
When the congestion resolution notification is received from the control bus 305 via the control bus 308, the gate is controlled to select the output of the regulation path waiting buffer 406, and the packet data connected to the regulation path queue of the buffer is output to the transmission path 203. I do. Thereafter, the gate 410 is controlled again to select the output of the passage route waiting buffer 407.

The accumulation amount monitoring unit 408 monitors the number of packet data accumulated in the passage route waiting buffer 407, and detects a congestion state by detecting that the number of packet data exceeds a predetermined value. When the congestion state is detected, the control processor 305 of FIG. 3 is notified via the control bus 308.

On the other hand, the packet data from the transmission path 203 is input to the transmission path decoding unit 411, where it is decoded and converted into packet data of a common protocol independent of the type of communication medium. Then, it is connected to the reception queue of the reception buffer 412, from which it is sent to the transfer destination determination unit 303 of FIG. 3 via the input / output unit 401.

Next, FIG. 5 shows the route information table storage unit 30 of FIG.
6 is a diagram showing a data configuration of a path information table TBL1 stored in 6. FIG. In this embodiment, in the packet communication network 201 shown in FIG. 2, an arbitrary terminal accommodating unit (an assembling / disassembling unit 302 in FIG. 3 or a P in FIG.
Termination which is not shown in FIG. 3 in FIG. 3 for accommodating the BX206 _C,
(Hereinafter the same) to all the communication paths from the arbitrary node to the arbitrary terminal accommodating unit, and a unique path number is assigned to each of them. If it collapses, the communication path of “accommodating unit of terminal 203 _A1 of node 202 _A → node 202 _B → accommodating unit of terminal 204 _D1 of node 202 _D ” is route 1, “accommodating unit of terminal 203 _A1 of node 202 _A →
Node 202 _B → communication of node accommodating portion 202 _C of the terminal 204 _C1 "route path 2, is as that. In this case, for example, a communication path that of FIG. 2, "accommodating portion of the node 202 receiving unit of the terminal 203 _A1 of _A → node 202 _B → node 202 _D terminal 204 _D1", the "node 202 _A of the terminal 203 _A1 Containment department → Node 202
It is assumed that a different path number is assigned to a communication path “ _B → node 202 _C → accommodating unit of terminal 204 _D1 of node 202 _D ”. Then, for each of the transmission paths 203 _AB , 203 _AD , 203 _BC , 203 _BD , 203 _DC, etc. constituting the packet communication network of FIG. 2, which path number communication path is included in the transmission path Is extracted. The information extracted for the entire packet communication network 201 in FIG. 2 is stored as a route information table TBL1 in each node in FIG.
202 _A , 202 _B , 202 _C, 202 _D, etc. route information table storage unit
306 (FIG. 3) is stored as a common table.
This storing operation is performed when starting up a line or setting each communication path.

Next, FIG. 6 shows the data configuration of the restricted route table TBL2 stored in the restricted route table storage unit 404 of FIG. 4 in each transmission path accommodation unit 301 of FIG. 3 in each node 202 of FIG. FIG. In the same table, each transmission path accommodation unit 30
In FIG. 1 (see FIG. 3), for each path number in the communication path included in the transmission path 203 accommodated in the accommodation unit, the output of packet data transmitted through that path is restricted or not restricted. Is specified by the flag “1” or “0”. This specification is, as described above,
It is set via the control bus 308 by the control processor 305 in FIG. For example FIG. 6 (a) is an example showing the contents of the regulation route table TBL2 stored in the regulation route table memory unit 404 in the transmission path storing portion 301 for accommodating the transmission line 203 _AB node 202 _A, the current The route 1 and the route 2 indicate that “pass” is specified, and the route 3 indicates that the “regulation” is specified. Also, FIG. 6 (b), the transmission path 20 of the node 202 _B
In the example shown the contents of the regulation route table TBL2 stored in the regulation route table memory unit 404 in the transmission path storing portion 301 for accommodating the 3 _BC, currently, the path 2 is "pass" is instructed, the route 3
And route 4 indicate that "regulation" is instructed.

The operation of the embodiment of the present invention having the above configuration will be described below with reference to the operation explanatory diagram of FIG.

In the example of FIG. 7, the packet communication network of FIG.
In 201, one terminal accommodating portion of the "node 202 _A → node 2
The communication path “02 _B → a certain terminal accommodating unit of another node” is route 1 and “a certain terminal accommodating unit of the node 202 _A → node 202 _B →
A communication path of “node 202 _C → a certain terminal accommodating unit of another node” is route 2, “a certain terminal accommodating unit of the node 202 _A → node”.
A communication path of “202 _B → node 202 _C → a certain terminal accommodation unit of the node 202 _D ” is route 3, “a certain terminal accommodation unit of the node 202 _B →
A communication route of “node 202 _B → node 202 _C → a certain terminal accommodating unit of node 202 _D ” is set as route 4.

Then, FIG. 7 shows an example in which congestion occurs in the packet transmission unit of the transmission line accommodating unit 301 for accommodating the transmission line 203 _DC node 202 _C.

First, the storage amount monitoring unit 408 (see FIG. 4) of the transmission path accommodation unit 301 that accommodates the transmission path 203 _DC is
The congestion state (overload, hereinafter the same) is detected by detecting that the number of packet data stored in 07 becomes a predetermined value or more.

When congestion is detected, notifies congestion detection is performed via the control bus 308 node 202 _C of the control processor 305 (see FIG. 3). The control processor 305 sends a regulation notification indicating that congestion has occurred on the transmission line 203 _DC from the common line signal unit 307 to the common line 309. As a result, all other nodes 202 _A , 202 of the packet communication network 201 shown in FIG.
The restriction notification is made of _B and 202 _D.

Control processor 305 of each node receiving the notification
(FIG. 3) refers to the table corresponding to the transmission path 203 _DC among the path information tables TBL1 stored in the path information table storage unit 306 in FIG. 3 based on the above-described regulation notification. Thereby, as shown in FIG. 5, information indicating the route 3 and the route 4 is extracted. And the control processor 30
In step 5, it is determined whether or not the communication path having the path number is included in the transmission path accommodated by the own node, for example, by referring to a call control table (not shown). If there is a communication path included in the transmission path accommodated by the own node, the control processor 305 transmits, via the control bus 308, a restriction in the transmission path accommodation unit 301 accommodating the transmission path 203 including the communication path. Route table storage unit 404 (fourth
(Refer to the figure.)
Is set to a flag "1".

In the example of FIG. 7, the control processor 30 of the node 202 _B which has received the restriction notification of transmission line 203 _DC from node 202 _C
5 extracts the route 3 and the route 4 from the route information table TBL1 as shown in FIG. Then, after it is determined that it is included in its own node both paths, both of the restriction path table TBL2 of the restriction path table storing unit 404 in the transmission path storing portion 301 for accommodating the transmission line 203 _BC that contains both routes As shown in FIG. 6B, a flag “1” indicating “restriction” is set at an address corresponding to the route. The control processor 305 of the node 202 _A which has received the same restriction notification and the extracts route 3 and route 4 from the route information table TBL1 as above. Then, after determining that the path 3 is included in the own node, the path of the restriction path table TBL2 of the restriction path table storage unit 404 in the transmission path accommodating unit 301 that accommodates the transmission path 203 _AB including the path 3 is determined. A flag "1" indicating "restriction" is set at the address corresponding to "3" as shown in FIG. 6 (a).

Using the above-described restriction route table TBL2, a restriction operation as described below is performed in each transmission path accommodation unit 301 in FIG. That is, in the transmission path storing portion 301 for accommodating the transmission line 203 _BC nodes 202 _B, packets highway 3
When packet data is input from 06 through the distribution unit 304 (see FIG. 3) to the input / output unit 401 in FIG. 4, the path number extraction unit 402 determines the path number 411 of the communication path through which the packet data is transmitted. Is extracted. If the route number 411 indicates, for example, the route 2, a regulated route flag 412 of “0” indicating “pass” is output to the select 405 (see FIG. 6B). Thereby, the selector 405
Connects the packet data to the passing path queue of the passing path waiting buffer 407. On the other hand, the gate control unit 409
Normally selects the output of the passage path waiting buffer 407 by controlling the gate 410 as described above. This allows
Packet data indicating a route 2 is transferred as usual on the transmission path 203 _BC. On the other hand, if the path number 411 indicates, for example, the path 3 or the path 4, a restriction path flag 412 of “1” indicating “restriction” is output to the selector 405 (see FIG. 6B). ). Thus, the selector 405
The packet data is connected to the restriction route queue of the restriction route waiting buffer 406. In this case, as described above, since the output of the passage route waiting buffer 407 is normally selected by controlling the gate 410, the packet data indicating the route 3 or the route 4 connected to the regulated route queue is the seventh data. as shown in the shaded portion of the node 202 _B of FIG, output regulated not sent to the transmission line 203 _BC.

Similar to the node 202 _B described above, the transmission line 203 of node 202 _A
Input / output unit 401 in transmission path housing unit 301 that houses _AB (Fig. 4)
If the path data 411 extracted by the path number extraction unit 402 indicates, for example, the path 1 or the path 2, the restricted path flag 41 of “0” indicating “pass” is input.
2 is output to the selector 405 (see FIG. 6A). As a result, the selector 405 connects the packet data to the passing path waiting example of the passing path waiting buffer 407, and the packet data indicating the path 1 and the path 2 is transmitted to the transmission path 203 _AB
Forwarded as usual. In contrast, route number 411
However, if it indicates, for example, the path 3, a restriction path flag 412 of "1" indicating "restriction" is output to the selector 405 (see FIG. 6A). Thus, the selector 405
Connect the packet data to the regulation route queue of the regulation route queue buffer 406, the packet data indicating route 3, as shown in the shaded portion of Figure 7 node 202 _A, not sent to the transmission line 203 _AB Output is regulated.

By the above operation, in the example of FIG.
The packet data of the route 3 and the route 4 toward the _DC can be quickly regulated, and the regulated route waiting buffer shown in FIG.
406 overflows it without the transmission line 203 at node 202 _C
The congestion state at the exit to _DC can be quickly eliminated. In this case, the transmission paths 203 _AB and 203 _BC
Only the packet data of the communication route of the route 3 and the route 4 passing through the 203 _DC is regulated, and the packet data of the other communication route of the route 1 and the route 2 are not regulated and are transferred as usual. Therefore, it is possible to minimize the spread of the congestion state in the transmission path 203 _DC to other parts.

The above regulation operation, passage path queue buffer 407 of the transmission line accommodating unit 301 transmission path 203 _DC node 202 _C is housed
When the congestion state in, the storage amount monitoring unit 413 of the storage unit notifies the control processor 305 (see FIG. 3) via the control bus 308 of the elimination of the congestion state of the transmission path 203 _DC . Subsequently, the control processor 305 sends a sibling notification from the common line signal unit 307 to the common line 309 indicating that the congestion state on the transmission line 203 _DC has been resolved. Thus, all other nodes 202 _A and 202 _B of the packet communication network 201 shown in FIG.
And the notification is performed in 202 _D. The control processor 305 of each node that has received this notification, as in the case of the regulation operation, transmits the transmission path 203 out of the path information table TBL1 stored in the path information table storage unit 306 in FIG.
Refer to the table corresponding to _DC . Thereby, as shown in FIG. 5, information indicating the route 3 and the route 4 is extracted. Then, the control processor 305 determines whether or not the communication path having the path number is included in the own node. If the communication path included in the own node exists, the control processor 305 congests the control unit 305 via the control bus 308 in the gate control unit 409 in the transmission path accommodation unit 301 that accommodates the transmission path 203 including the communication path. Notify the cancellation. Accordingly, the control unit controls the gate to select the output of the restriction route waiting buffer 406, and outputs the packet data connected to the restriction route queue of the buffer to the transmission line 203. Thereafter, the gate control unit 409 controls the gate 410 again to select the output of the passage route waiting buffer 407. Along with this operation, the flag “1” indicating “regulation” of the address corresponding to the communication path in the restriction path table storage unit 404 (see FIG. 4) in the transmission path accommodation unit 301 is released, and “pass” is performed. Flag “0” is set. By the above operation, the output restriction of the hatched portion of the node 202 _B and node 202 _A of FIG. 7 is released.

FIG. 8 compares the above embodiment of the present invention with the conventional example. As can be seen from FIG. 8 (a), in the conventional example,
When a congestion state occurs in the transmission path 203 'accommodated in one node 202', all the transmission paths related to the communication paths included therein are regulated as shown by hatched portions in FIG. For this reason, the congestion state may spread to other nodes or transmission paths. On the other hand, as can be seen from FIG. 8B, in the embodiment of the present invention, when a congestion state occurs in the transmission line 203 'accommodated in one node 202', the other transmission line 203 Since only the communication paths included in the transmission path 203 'in which congestion has occurred are regulated, very efficient path regulation can be performed.

〔The invention's effect〕

According to the present invention, at each packet switching node:
Only the packet data of the communication path toward the transmission path where congestion or the like has occurred in the transmission path is restricted, and the packet data of the other communication paths are not regulated and are transferred as usual.
Therefore, it is possible to minimize the spread of a congestion state such as congestion to another.

Further, notification to other packet switching nodes such as occurrence of congestion need only be made by notifying only the number of the transmission path and the like, and the control procedure can be simplified as compared with the conventional case. As a result, control by hardware becomes easy, the notification operation can be performed quickly, and packet data of a communication path toward a transmission path where congestion or the like has occurred can be quickly regulated for each packet switching node. Congestion such as congestion can be quickly eliminated.

As a result, burst traffic can be suppressed to a certain value or less, and the occurrence of a congestion state in the network can be effectively suppressed.

Furthermore, when a regulation queuing buffer is used for regulating packet data, the regulation is effectively performed at each packet switching node, so that the buffered packet data does not overflow in the buffer, and the packet processing by the regulation process is performed. It is possible to prevent the occurrence of disposal.

[Brief description of the drawings]

Fig. 1 is a block diagram of the present invention, Fig. 2 is an overall configuration diagram of a packet communication network, Fig. 3 is a block diagram of a packet switching node, and Fig. 4 is a configuration of a transmission path accommodating unit according to the present invention. FIG. 5, FIG. 5 is a configuration diagram of a route information table TBL1, FIGS. 6A and 6B are configuration diagrams of a regulation route table TBL2, FIG. 7 is an explanatory diagram of a route regulation operation, FIG. (A), (b) is the figure which compared the Example of this invention with the conventional example. 101 communication path storage means 102 congestion state detection means 103 congestion state notification means 104 communication path discriminating means 105 communication path control means 106 transmission path 107 congestion Status notification 107, 108... Packet data.

 ────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-270439 (JP, A) JP-A-2-260735 (JP, A) JP-A-1-240048 (JP, A) JP-A-60-1985 177760 (JP, A) JP-A-2-237251 (JP, A) IEEE International Conference on Communications, June 1987, Vol. 2, P. 974-979

Claims (3)

(57) [Claims] 1. A packet communication network comprising a plurality of terminals and a transmission line connecting between packet switching nodes accommodating them and between packet switching nodes. For each transmission path (106) in the network, which of the communication paths from any terminal accommodation unit of any packet switching node to any terminal accommodation unit of any other packet switching node Communication path storage means (101) for storing whether or not it is included; congestion state detection means (102) for detecting the congestion state of the transmission path (106) accommodated in its own packet switching node; detection by the congestion state detection means Transmission line (10
Congestion status notification means (103) for notifying another packet switching node of the congestion status of (6) as congestion status notification (107); and congestion status notification (10) from another packet switching node.
7), a communication path included in the transmission path corresponding to the congestion state notification is searched from the communication path storage means (101), and the transmission path accommodated by the own packet switching node among the searched communication paths. Communication path determination means (104) for determining a communication path included in (106); and sending of packet data (108) transferred on the communication path determined by the communication path determination means to the congestion state notification (104). Communication path control means (105) for controlling based on (107)
And a route-based regulation method characterized by having: 2. The congestion state detecting means detects either the occurrence of a congestion state of a transmission line accommodated in the own packet switching node or the elimination of the congestion state, and the congestion state notification is based on the own packet switching node. A congestion state occurrence notification indicating that a congestion state has occurred in a transmission path accommodated in the node and a congestion state resolution notification indicating that the congestion state occurring in the transmission path accommodated in the own packet switching node has been resolved; The communication path control unit, when receiving the congestion state occurrence notification from the another packet switching node, sends out the packet data transferred on the communication path determined by the communication path determination unit. Is regulated, and when the congestion state elimination notification is received from the other packet switching node, it is determined by the communication path determining unit. Releasing the restriction in Shin route, the route-based regulation system of claim wherein the. 3. A transmission waiting buffer means for holding packet data to be transmitted to the own transmission line for each transmission line accommodated in the own packet switching node, and restricting transmission to the own transmission line. A restriction buffer unit for holding packet data, wherein the congestion state detection unit is provided for each transmission line accommodated in the own packet switching node, and the amount of packet data stored in the transmission queue buffer unit To detect either the occurrence of the congestion state or the elimination of the congestion state, the communication path control means is provided for each transmission path accommodated in the own packet switching node, and the communication path The control means stores information indicating whether or not transmission of packet data is currently restricted for each of the communication paths included in the own transmission path, and stores the other packet. When the congestion state occurrence notification is received from the packet switching node, information indicating that the restriction is being performed on the communication path determined by the communication path determining means is set, and the other packet switching is performed. A restriction route setting storage unit for setting information indicating that the restriction on the communication path determined by the communication path determination unit has been released when receiving the congestion state elimination notification from the node; Communication path extraction means for extracting a communication path of packet data; detecting, from the restriction path setting storage means, whether or not the communication path extracted by the communication path extraction means is restricted; When the restriction is not performed, the packet data to be transmitted is held in the restriction waiting buffer unit, and when the restriction is not performed, the transmission is performed. Selector means for holding packet data to be performed in the transmission waiting buffer means, and when receiving the congestion state elimination notification from the other packet switching node, the packet data held in the regulation waiting buffer means 3. A path unit according to claim 2, further comprising: gate means for transmitting the packet data held in said transmission waiting buffer means to said own transmission path, and transmitting the packet data held in said transmission waiting buffer means to said own transmission path. Regulation system.