JP2003198613A - Edge type packet transfer system, packet transfer network and transfer regulating method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize impartiality concerning network resources usage between applications. <P>SOLUTION: This packet transfer network is provided with a plurality of packet transfer systems (2A, 2B) accommodating a plurality of terminals (1A-1F), and a core router (3) accommodating at least one packet transfer system. The packet transfer system (2B) which has detected generation of confusion transmits a confusion informing packet by making a transmission origin address of a packet which is a cause of confusion be a destination address. The packet transfer system (2A) which has received the confusion informing packet specifies the transmission origin address and the destination address of the packet which is the cause of confusion, and performs transmission regulation concerning packet transfer of the specified destination and transmission origin address. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique to be applied when controlling fairness of network resource utilization between user terminals in a packet transfer network.

[0002]

2. Description of the Related Art In a conventional packet transfer network,
The packet transfer device that has detected the congestion, with respect to the user terminal that has transmitted the packet causing the congestion, for example, IE
Congestion was notified using the ICMP Source Quench packet specified by RFC792 of TF. Further, the user terminal that has received the congestion notification has stopped transmitting the packet having the corresponding destination address.

[0003]

In the conventional packet transfer network, it is the user terminal that determines whether packet transmission is continued or stopped. For this reason, when the packet transfer device notifies congestion to a plurality of user terminals, if the specific user terminal does not intentionally stop the packet transmission, only that user terminal can advantageously perform the packet transfer. In other words, fairness regarding the use of network resources cannot always be realized between user terminals. Therefore,
The present invention realizes fairness regarding the use of network resources among user terminals regardless of the behavior of the user terminals.

Further, in the conventional packet transfer network, since the transmission is stopped based on the packet address, a specific application flow (for example, the same TCP connection is transferred between the same user terminals). It was difficult to suppress the transmission of only IP packet groups). Therefore, when a large amount of data is transferred by FTP or the like, there arises a problem that it interferes with voice communication such as VoIP performed between the same user terminals.

When TCP packets having a transmission rate control function and UDP packets having no transmission rate control function coexist, only UDP packets are not suppressed in transmission and network resources are preferentially consumed. There was a problem. Therefore, fairness could not be realized between the application using TCP and the application using UDP.

Further, in the conventional packet transfer network, even if the priority for transfer is defined in the packet, only the priority is reflected in the transfer conflict, and the control in which the priority is reflected can be performed when the transmission is restricted. There wasn't.

Further, in the conventional packet transfer network, when the traffic from one terminal to another terminal is heavy, the packet transfer from another terminal suffers from traffic interference and the network throughput decreases. It was pointed out.

Therefore, it is an object of the present invention to enable continuation / stop of transmission for each application flow even between the same user terminals, and to realize fairness in utilization of network resources among applications.

[0009] Another object of the present invention is to suppress interference of a specific terminal whose received traffic is heavy with the received traffic to another terminal which is light, thereby further improving the throughput of the entire network.

Further, another object of the present invention is to realize fairness between the same packet priority classes while realizing quality differentiation between different packet priority classes.

[0011]

In order to solve the above-mentioned problems, a packet transfer network according to the present invention comprises a plurality of edge type packet transfer devices accommodating terminals and one or more edge type packet transfer devices. In a packet transfer network comprising a core type packet transfer device accommodating a packet, the edge type packet transfer device, when congestion occurs, an identifier indicating congestion, and a destination address and a source address of a packet that causes congestion Congestion notification packet generating means to generate a congestion notification packet including, the congestion notification packet, means for transmitting the source address of the packet that is the cause of congestion as the destination address, if the congestion notification packet is received, Source address of the packet causing the congestion included in the received congestion notification packet The edge-type packet transfer device that detects congestion and that is the destination address of the packet that causes congestion Send congestion notification packet as address,
The edge-type packet transfer device that receives the congestion notification packet specifies the source address and the destination address of the packet causing the congestion, and restricts the transmission of the packet transfer of the specified destination address and the source address. Characterize.

In the present invention, instead of the user terminal on the transmission side, the packet transfer apparatus accommodating the user terminal on the transmission side receives the congestion notification and regulates the transmission based on the destination address and the source address. As a result, it is possible to achieve fairness regarding the use of network resources between user terminals regardless of the behavior of the user terminals.

The edge type packet transfer apparatus according to the present invention, when congestion occurs, generates a congestion notification packet including an identifier indicating congestion, a destination address of a packet causing congestion and an address of a terminal of a transmission source. Notification packet generating means, the congestion notification packet, means for transmitting as a destination address the source address of the packet causing the congestion, the congestion notification packet addressed to the terminal accommodated by the edge type packet transfer device When received, a transmission restriction means for specifying the source address and the destination address of the packet causing the congestion included in the received congestion notification packet and restricting the transmission of the packet of the specified destination and the source address It is characterized by including and.

Further, in the transfer regulation method in the packet transfer network according to the present invention, when the edge type packet transfer device accommodating the terminating terminal causes congestion, an identifier indicating the congestion and a destination address of the packet causing the congestion And a congestion notification packet including a source address, and transmits the congestion notification packet as the destination address of the source address of the packet causing the congestion, which is accommodated by the edge-type packet transfer device that accommodates the originating terminal. When the congestion notification packet destined to the source terminal is received, the source address and the destination address of the packet causing the congestion included in the received congestion notification packet is specified, and the packet corresponding to these specified information is specified. It is characterized by restricting transmission for forwarding.

In a preferred embodiment of a transfer restriction method for a packet transfer network according to the present invention, a congestion notification packet includes header information of a packet causing congestion in a payload and an identifier indicating congestion in a header or payload, The edge-type packet transfer device accommodating the calling terminal refers to the payload of the received congestion notification packet to identify the source address and the destination address of the packet causing the congestion.

According to another preferred embodiment of the transfer restriction method for a packet transfer network according to the present invention, the congestion notification packet includes header information of a packet which caused congestion, header information of a higher level protocol, and a header to be referred to. It is characterized in that an identifier indicating the range of information is included in the payload, and the edge-type packet transfer device accommodating the transmission terminal regulates the transmission by using the header information of the upper protocol in addition to the header information of the packet. By including not only packet header information (destination address and source address, etc.) but also higher-layer protocol header information in the congestion notification and transmission regulation information, it becomes possible to make the transmission regulation unit more detailed and It is possible to achieve fairness regarding the use of network resources among applications regardless of the seed condyle and the behavior.

Further, in a preferred embodiment of the transfer restriction method for a packet transfer network according to the present invention, an edge type packet transfer device accommodating a source terminal extracts a plurality of types of packets that cause congestion, and extracts these packets from these packets. hand,
It is characterized in that the priority of the congestion notification is determined by referring to the header information and the header information of the upper protocol, and the congestion notification packet is transmitted only to the source of the packet with the high priority of the congestion notification. When there are a plurality of congestion notification targets, the congestion notification is preferentially notified from the packet having the lower transfer priority, whereby the differentiation of the network resource utilization between the transfer priority classes can be realized.

Further, in a preferred embodiment of the transfer restriction method for a packet transfer network according to the present invention, when the edge-type packet transfer device accommodating the originating terminal restricts transmission, the transfer given to the packet to be transferred is transferred. A feature is that those with a high priority are excluded from the targets of transmission restriction, and only those with a low transfer priority given to a packet to be transferred are included in the targets of transmission restriction. When there are multiple congestion notification targets, congestion notification is performed for all packets, and transmission restriction is applied only to packets with low transfer priority to differentiate network resource usage between transfer priority classes. Can be realized.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described below. FIG. 1 shows an example of the configuration of a network for explaining the present invention. For the sake of clarity, the network consists of six terminals, terminal 1 (1A), terminal 2 (1
B), terminal 3 (1C), terminal 4 (1D), terminal 5 (1
E) and the terminal 6 (1F). The terminal 1 (1A), the terminal 2 (1B) and the terminal 3 (1C) are respectively linked to the link 1,
It is accommodated in the edge router 2A which functions as an edge type packet transfer device via the link 2 and the link 3. In addition, the terminal 4 (1D), the terminal 5 (1E), and the terminal 6 (1
F) is accommodated in the edge router 2B via the link 4, the link 5, and the link 6, respectively. Further, the edge router 2A and the edge router 2B are accommodated in the core router 3 which is a core type packet transfer device via the link 7 and the link 8, respectively.

Here, the link band is 5 Gb / s for link 1, link 2, link 3, link 4, link 5 and link 6, and 10 Gb / s for link 7 and link 8.
And Further, as the IP address, IP # 1 is assigned to the terminal 1 (1A), IP # 2 is assigned to the terminal 2 (1B), and terminal 3 is assigned.
IP # 3 is assigned to (1C) and IP # 4 is assigned to terminal 4 (1D).
However, it is assumed that the terminal 5 (1E) is assigned IP # 5 and the terminal 6 (1F) is assigned IP # 6.

FIG. 2 shows the edge router 2A shown in FIG.
3 is a diagram showing an example of the configuration of an edge router for explaining the operation of the edge router 2B. FIG. Since the edge router 2A and the edge router 2B have the same configuration, the configuration of the edge router 2A will be described. These edge routers have a port 1, a port 2 and a port 3 for accommodating terminals, and a port 4 for accommodating them in a core router. Port 1, port 2 and port 3 are connected to the packet forwarder unit 10 that controls packet transfer. The output sides of the ports 1 to 3 pass through the first to third output queues 11 to 13 respectively, and the packet forwarder unit 1
0, and the input side is directly connected to the packet forwarder unit 10. In addition, the port 4 also uses the packet forwarder unit 1.
0, the output side of the port 4 is connected to the packet forwarder unit 10 via the fourth output queue 14 and the filter unit 15, and the input side is connected to the packet forwarder unit via the packet extracting unit 16. Connect to 10.

The edge router further includes a transmission suppressing unit 17 and a packet generating unit 18. The transmission suppressing unit 17 outputs filter information for controlling the transmission rate to the filter unit 15 according to the packet input from the packet extracting unit 16. The filter unit 15 filters the transmission packet based on the input filter information.
It should be noted that the filter information supplied from the transmission suppressing unit 17 to the filter unit 15 is invalidated and deleted after a certain period of time. The packet generator 18 uses the first to third output queues 1
The packets discarded in 1 to 13 are collected to detect the occurrence of congestion, a packet for congestion notification is generated by using this as an input, and this is output to the packet forwarder unit 10. That is, the packet generation unit functions as congestion occurrence detection means and congestion notification packet generation means.

FIG. 3 shows the packet generator 1 shown in FIG.
8 shows an exemplary configuration of a packet generation unit for explaining the operation of FIG. In this packet generation unit, the discard packet extraction unit 21 receives the discard packets output from the first to third output queues 11 to 13 of FIG. 2 via the packet finder unit 10. The packet received by the discard packet extraction unit 21 is sent to the header analysis unit 22, where the header contents such as the destination address and the source address of the packet that caused the congestion are analyzed. The analyzed content is sent to the packet generator 23.

The packet generator 23 generates a congestion notification packet based on the analysis contents of the header. The congestion notification packet includes, in addition to the header information of the packet that has caused the congestion, header information of a higher-level protocol and an identifier indicating the range of header information to be referred to, if necessary.

At this time, the congestion notification packet is provided with a congestion notification priority in the reverse order of the transfer priority assigned to the discarded packet. If it becomes necessary to generate multiple congestion notification packets with the same content in a short period of time, instead of generating multiple congestion notification packets, keep the number of congestion notification packets at one. Set the priority of the congestion notification to be given to the congestion notification packet to a high priority.

The congestion is identified by, for example, the IC specified by IETF RFC792 as the format of the packet payload.
It is realized by diverting the MP Source Quench format. This is identified by the ICMP TYPE value = 4. Furthermore, CODE
By expanding the value and describing the payload length to be referenced here, the CODE value can be used as an identifier indicating the range of header information to be referenced. The generated congestion notification packet is sent to the priority control unit 24. In the priority control unit 24,
The packets generated by the packet generation unit 23 are arranged in the order of priority of congestion notification, and the congestion notification with the highest priority is
Select some. The selected packet is sent to the packet sending unit 25. The packet transmission unit 25 transfers the transmitted packet to the outside.

FIG. 4 shows an example of the configuration of the filtering table to be mounted on the filter section 15 shown in FIG. In this table, the search keys are the destination IP address (4A), the source IP address (4B), the priority class (TOS) (4C), and the protocol (TCP / UDP).
(4D), destination port (4E), source port (4F)
It consists of. Flows entered in this table are
Transmission is restricted.

In such a configuration, for example, the terminal 1
5G from (1A) and terminal 2 (1B) to terminal 4 (1D)
The packet is transmitted at b / s, and the terminal 3 (1C) transmits to the terminal 5
Packet transmission shall be performed to (1E) at 5 Gb / s. At the beginning of packet transmission, the edge router 2A tries to pack a total of 15 G / s of traffic in the link 7 (1P) of 10 Gb / s, so packet discard occurs. The packet discard from each terminal at this time is stochastically proportional to the input band, and is therefore substantially equal. Therefore, packets pass through the edge router 2A from each terminal at a rate of about 3.3 Gb / s. In this situation,
Further, in the edge router 2B, for the link 4 (1M) addressed to the terminal 4 (1D), from the terminal 1 (1A) to 3. 3Gb /
At 3.3 Gb / s from s and the terminal 2 (1B), packet discard occurs because it tries to pack a total of about 6.6 Gb / s of traffic into the 5 Gb / s link. On this occasion,
Probabilistically, the packet discard from each terminal is proportional to the input band, and is therefore almost equal. Therefore, terminal 1 (1
About 2.5 Gb from A) and Terminal 2 (1B)
Packets pass through the edge router 2B at a rate of / s.

Therefore, the terminal 1 (1A) and the terminal 2
(1B) to terminal 4 (1D), terminal 3 (1C) to terminal 5 (1E)
If a packet is transmitted at 5 Gb / s to each terminal, the actual throughput will be 2.5 Gb / s from terminal 1 (1A) to terminal 4 (1D) and 2.5 Gb from terminal 2 (1B) to terminal 4 (1D). / S From terminal 3 (1C) to terminal 5 (1E), it becomes 3.3 Gb / s. This total value is 8.3 Gb / s.

Here, the following matters. (1) The bandwidth of link 7 (1P) and link 8 (1Q) is 1
0 Gb / s, but the total throughput is 8.3 G
It has decreased to b / s. (Backbone transfers invalid traffic) (2) Transfer from terminal 3 (1C) to terminal 5 (1E) is 5G for both transmission side link 3 (1L) and reception side link 5 (1E)
Although it is b / s, the throughput is 5 Gb / s or less. (Fairness has not been realized between the user who sends a packet to terminal 4 (1D) and the user who sends a packet to terminal 5 (1E).) (3) Terminal 1 (1A) to terminal 4 ( Packets are not prioritized even though traffic to 1D) is more important than traffic from terminal 2 (1B) to terminal 4 (1D).

In order to comprehensively solve the above-mentioned problems,
In the first embodiment of the packet transfer system according to the present invention,
The edge router 2B notifies the edge router 2A of congestion. Here, in order to explain the operation of the edge router 2B, in FIG.
Assume that port 2 is assigned to terminal 4 (1D), terminal 5 is assigned to terminal 5 (1E), port 3 is assigned to terminal 6 (1F), and port 4 is assigned to core router 3.

At the second edge router 2B, the terminal 4
The traffic destined for (1D) has an input of 6.6 Gb / s and an output of 5 Gb / s, so packet discard occurs in the first output queue. The packets discarded here are collected in the packet generation unit 18 by the function of the discarded packet extraction unit 21 of the packet generation unit 18. In the packet generation unit 18, the header analysis unit 22 analyzes the discarded packet. Here, by referring to the transmission / reception IP address of the discarded packet, terminal 1 (1A) to terminal 4
It is analyzed that the packet to (1D) and the packet from terminal 2 (1B) to terminal 4 (1D) are discarded.

Therefore, a congestion notification packet with the destination address IP # 1 and a congestion notification packet with the destination address IP # 2 are generated. The payload of these congestion notification packets is loaded with data in the format defined by the ICMP Source Quench (Type = 4). This includes the source address and destination address of the discarded packet that triggered the generation of the congestion notification packet. The same congestion notification priority is given to the two congestion notification packets generated here. These congestion notification packets are scheduled by the priority control unit 24 in the same priority order, and are packet-transmitted through the packet transmission unit 25. These congestion notification packets are sent to the core router 3
To reach the edge router 2A.

Here, in order to explain the operation of the edge router 2A, in the edge router 2A, port 1 is terminal 1 (1A), port 2 is terminal 2 (1B), port 3 is terminal 3 and so on.
Port 4 is assigned to core router 3 in (1C).

When the packet extraction unit 16 refers to the protocol field of the packet of the packet input through the port 4 in the edge router 2A regardless of the destination address of the packet, and identifies that this is ICMP. In addition, refer to the ICMP header,
If you identify this as a Source Quench,
This packet is extracted as a congestion notification packet and transferred to the transmission suppressing unit 17. The transmission suppressing unit and the filter unit form the transmission restricting means of the present invention. The transmission suppressing unit 17 analyzes the payload of the transferred congestion notification packet,
The destination IP address and the source IP address are specified, filter information for controlling the filter unit 15 is created based on these information, and the filter information is supplied to the filter unit 15.

The filter unit 15 of the edge router has a band control function. For example, the transmission suppressing unit 17 makes a setting such that the transmission rate of the filter unit 15 is reduced by 0.1 Gb / s each time it receives one congestion notification packet within a predetermined time period. Alternatively, the transmission rate can be lowered according to the number of congestion notification packets received during a predetermined time period. When the congestion notification packet is not received within the predetermined time period, the transmission rate can be increased by 0.1 Gb / s. Alternatively, if the congestion notification packet is not received within the predetermined time period, the transmission rate can be controlled to return to the initially set transmission rate. With this configuration, the transfer band of 5 Gb / s is initially used for both the transfer from the terminal 1 (1A) to the terminal 4 (1D) and the transfer from the terminal 2 (1B) to the terminal 4 (1D). Even if it is allocated, the transfer band is gradually narrowed down, and finally both converge to about 2.5 Gb / s.

As a result, the edge router 2A becomes the terminal 1
From (1A) to terminal 4 (1D) 2. At 5Gb / s, terminal 2 (1
From B) to terminal 4 (1D) 2. Terminal 3 (1C) at 5Gb / s
From the terminal 5 (1E) to the terminal 5 (1E), a total of 10 Gb / s of traffic will be packed in the link 7 (1P) of 10 Gb / s.

In this situation, further, in the edge router 2B, from the terminal 1 (1A) to the 5 Gb / s link 4 (1M) addressed to the terminal 4 (1D), 2. 5Gb / s traffic and 2 from terminal 2 (1B). 5G also tries to reduce the traffic of / s, and packet discard does not occur. In addition, 5Gb / s link 5 (1
N) will try to pack 5 Gb / s of traffic from the end 3 (1C), and packet discard will not occur.

As a result, the terminal 1 (1A) and the terminal 2
(1B) to terminal 4 (1D), terminal 3 (1C) to terminal 5 (1E)
When attempting to perform packet transmission at 5 Gb / s respectively, the actual throughput when implementing the present invention is
Transfer from terminal 1 (1A) to terminal 4 (1D) at 2.5 Gb / s, then transfer from terminal 2 (1B) to terminal 4 (1D) 2. 5 Gb / s
5Gb / from terminal 3 (1C) to terminal 5 (1E)
will be transferred in s. This total value is 10 Gb / s, and the total throughput value is significantly increased as compared with the case where the present invention is not applied.

When the traffic addressed to the terminal 4 (1D) and the traffic addressed to the terminal 5 (1E) are compared, if the present invention is not applied, the traffic addressed to the terminal 5 (1E) is Throughput is 3 even if the bandwidth is 5 Gb / s. 3G
Although it was reduced to b / s, the throughput is improved to 5 GB / s by applying the present invention. That is, the traffic from the terminal 3 (1C) to the terminal 5 (1E) is
In the case where the present invention is not applied, the throughput is reduced due to the interference of the traffic addressed to the other terminal from another terminal. However, by applying the present invention, it is possible to suppress the reduction in the throughput. Become. This means that the fairness among users is improved from the viewpoint that interference from heavy users and the like can be prevented.

Even if the terminal 1 (1A) transmits a TCP packet and the terminal 2 (1B) transmits a UDP packet, there is no change in that these are treated fairly. On the other hand, when the present invention is not applied in such a mixed situation of TCP packets and UDP packets, only the TCP packets are suppressed from being transmitted by the user terminal, and the actual throughput is less than 1 (1).
A) to terminal 4 (1D) 0 Gb / s, terminal 2 (1B) to terminal 4 (1D) 5 Gb / s, terminal 3 (1C) to terminal 5
5Gb / s to (1E), terminal 1 (1A) and terminal 2 (1
In some cases, fairness may not be maintained with B). On the other hand, by applying the present invention, the above-mentioned unfairness between terminals can be removed and fairness between terminals can be maintained.

Next, as a second embodiment, the terminal 1 (1A)
A method for intentionally differentiating the quality between the terminal 2 and the terminal 2 (1B) regardless of the upper layer protocol such as TCP / UDP is shown. In the above-described first embodiment, the transmission suppressing unit 17 analyzes the payload of the transferred congestion notification packet, identifies the destination IP address and the source IP address, and sets this in the filter unit 15. At this time, the transmission restriction target is limited in advance to packets with low priority. The packet priority is identified by referring to the TOS field, for example. The regulation of the transmission restriction target can be performed by providing the table of the filter unit 15 with the TOS field (4C) as shown in FIG.

The transmission restriction in the filter unit 15 of the edge router can be performed by discarding the packet instead of suppressing the band.

Here, the packet from the terminal 1 (1A) to the terminal 4 (1D) is given a high priority, and the packet from the terminal 2 (1B) to the terminal 4 (1D) is given a low priority. If so, since the transmission restriction is applied only to the packets to which the low priority is given, the actual throughput is determined by the terminal 1 (1
A) to terminal 4 (1D) 5 Gb / s, terminal 2 (1B) to terminal 4 (1D) 0 Gb / s, terminal 3 (1C) to terminal 5
5Gb / s to (1E), terminal 1 (1A) and terminal 2 (1
It is possible to differentiate quality from B). Further, since this quality differentiation does not affect the packet addressed to the terminal 5 (1E), the fairness is maintained between the packet addressed to the terminal 4 (1D) and the packet addressed to the terminal 5 (1E). It remains. These phenomena do not depend on upper protocols such as TCP / UDP.

Next, as a third embodiment, the terminal 1 (1A)
Another method different from the second embodiment for intentionally differentiating the quality between the terminal 2 and the terminal 2 (1B) regardless of the type of higher-layer protocol such as TCP / UDP will be described. In the above-described first embodiment, in the packet generation unit 18, the header analysis unit 22 analyzes the discarded packet to generate the congestion notification packet.
Refer to the TOS field and end 4 from terminal 1 (1A)
It is assumed that the packet transfer priority to (1D) is identified to be higher than the packet transfer priority from the terminal 2 (1B) to the terminal 4 (1D). In this case, the packet generation unit 23 generates a congestion notification packet for applying back pressure, but the congestion notification packet is given a priority order opposite to the priority order given to the discarded packet. give. The ICMP Source Quench is loaded in the payload of the congestion notification packet. However, the CODE value
By describing a specific value that differs from the specifications, it is suggested to refer to the destination IP address, source IP address, and TOS field value.

For example, if the reference range is CODE value = 1 and the destination IP
Address, source IP address, CODE value = 2, destination
IP address, source IP address and TOS, CODE value = 3
, Destination IP address, source IP address and protocol, CODE value = 4, destination IP address, source IP address, TOS and protocol, CODE value = 5, destination IP address, source IP address, TOS, protocol , And destination port number and source port number are specified, 2 is described in the CODE value.

These congestion notification packets are scheduled by the priority control section 24 based on the priority order. That is, first, the terminal 4 for the terminal 2 (1B)
The congestion notification packet for (1D) is given a transmission opportunity, and the packet is transmitted through the packet transmission unit 25.
Here, the congestion notification packet addressed to the terminal 1 (1A) and addressed to the terminal 4 (1D) is not transmitted. When the congestion notification packet addressed to the terminal 4 (1D) is transmitted to the terminal 2 (1B), the priority control unit is reset and all the congestion notification packets that have not been transmitted and are accumulated are discarded.

The congestion notification packet addressed to the terminal 4 (1D) for the terminal 2 (1B) has the destination IP address of the terminal 2 (1D).
The IP address (IP # 2) of (1B) is described and reaches the edge router 2A via the core router 3. The edge router 2A analyzes the payload of the transferred congestion notification packet in the transmission suppressing unit 17, and
If the CODE value of ource Quench is 2, specify the destination IP address, source IP address, priority class (TOS),
This is set in the filter unit 15.

As a result, for example, an entry having the contents of the filter section table structure shown in FIG. 4 is generated. Transmission regulation in the filter section (2H) is not band suppression,
The packet is discarded. That is, after the entry is set, a packet addressed to the terminal 4 (1D) from the terminal 2 (1B) and matching the entry is discarded by the filter unit 15.

As a result, the actual throughput is
5Gb / s from (1A) to terminal 4 (1D), 0Gb / s from terminal 2 (1B) to terminal 4 (1D), terminal 3 (1C) to terminal 5
It becomes 5Gb to (1E), and it becomes possible to differentiate the quality between the terminal 1 (1A) and the terminal 2 (1B).

Since the quality differentiation does not affect the packet addressed to the terminal 5 (1E), the terminal 4 (1E)
The fairness remains maintained for the packet addressed to D) and the packet addressed to terminal 5 (1E).

These phenomena do not depend on a higher level protocol such as TCP / UDP. It is also possible to use TCP / UDP or TCP / UDP port numbers instead of TOS as flow information for transmission suppression. In this case, transmission control can be performed for each TCP / UDP type and each TCP / UDP port number, and quality can be differentiated between these flows.

[0053]

As described above, according to the present invention, regardless of the behavior of the user terminal, fairness regarding the use of the network resource between the user terminals is realized, and regardless of the seed condyle and the behavior of the application, At the same time, fairness regarding network resource utilization between applications is also realized. Further, the use efficiency itself of the network resource is improved in order to prevent unnecessary discarding.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an example of a packet transfer system according to the present invention.

FIG. 2 is a diagram showing a configuration of an example of a packet transfer device, that is, an edge router.

FIG. 3 is a diagram showing a configuration of a packet generation unit.

FIG. 4 is a diagram showing a table configuration of a filter unit.

[Explanation of symbols]

1A terminal 1 1B terminal 2 1C terminal 3 1D terminal 4 1E terminal 5 1F terminal 6 1J Link 1 1K link 2 1L link 3 1M link 4 1N link 5 1O link 6 1P link 7 1Q link 8 2A, 2B edge router 3 core router 10 Packet forwarder section 16 Packet extractor 17 Transmission suppression unit 18 Packet generator

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hiroyuki Hara             2-3-1, Otemachi, Chiyoda-ku, Tokyo             Inside Telegraph and Telephone Corporation (72) Inventor Yoshiyuki Hamaoka             2-3-1, Otemachi, Chiyoda-ku, Tokyo             Inside Telegraph and Telephone Corporation F term (reference) 5K030 GA13 HA08 JA11 JT02 LC11                       LC14

Claims (12)

[Claims] 1. An edge-type packet transfer device used in a packet transfer network, comprising: an edge-type packet transfer device accommodating a terminal; and a core-type packet transfer device accommodating an edge-type packet transfer device. When it occurs, a congestion notification packet generating unit that generates a congestion notification packet including an identifier indicating congestion and a destination address and a source address of the packet that is the cause of the congestion, and the congestion notification packet that caused the congestion. When a congestion notification packet addressed to the means for sending the source address of the packet as the destination address and the terminal accommodated by the edge type packet transfer device is received, it causes the congestion included in the received congestion notification packet. Specify the source address and destination address of the packet and specify the specified source and destination addresses. An edge-type packet transfer device comprising: a transmission restriction unit that restricts transmission of a packet packet. 2. A packet transfer network comprising a plurality of edge type packet transfer devices accommodating terminals, and a core type packet transfer device accommodating edge type packet transfer devices, wherein the edge type packet transfer devices are When it occurs, a congestion notification packet generating unit that generates a congestion notification packet including an identifier indicating congestion and a destination address and a source address of the packet that is the cause of the congestion, and the congestion notification packet that caused the congestion. A means for transmitting a source address of a packet as a destination address, and when the congestion notification packet is received, the source address and the destination address of the packet causing the congestion included in the received congestion notification packet are specified, Sending that regulates sending for packet forwarding of specified source and destination addresses The edge-type packet transfer device that includes the regulation means transmits the congestion notification packet with the source address of the packet causing the congestion as the destination address and receives the congestion notification packet. Is a packet transfer network, which identifies a source address and a destination address of a packet that causes congestion and regulates transmission of packet transfer of the identified source and destination addresses. 3. The transfer restriction method for a packet transfer network according to claim 2, wherein the edge-type packet transfer device accommodating the terminating terminal causes an identifier indicating congestion and a cause of congestion when congestion occurs. A congestion notification packet containing the destination address and source address of the packet is generated, the congestion notification packet is sent as the source address of the packet that caused the congestion, and the edge-type packet transfer that accommodates the originating terminal When the device receives a congestion notification packet destined to the accommodating source terminal, the device identifies the source address and the destination address of the packet causing the congestion included in the received congestion notification packet, and these identified A transfer restriction method characterized in that transmission restrictions are applied to packet transfers corresponding to information. 4. The transfer restriction method according to claim 3, wherein the edge-type packet transfer device accommodating the called terminal includes a destination and a source address of a packet causing congestion in the congestion notification packet. As a means, there is a means for including a part or all of the header information of the packet causing the congestion in the header or the payload of the congestion notification packet, and the edge-type packet transfer device accommodating the originating terminal receives the congestion notification. A transfer regulation method comprising means for referring to a payload of a received congestion notification packet as means for specifying a packet source address and a destination address included in a packet that cause congestion. 5. The transfer restriction method according to claim 3, wherein the edge-type packet transfer device accommodating the terminating terminal has a higher-level protocol in addition to the header information of the packet causing the congestion in the congestion notification packet. The header type and the identifier indicating the range of the header information to be referred to are included in the payload, and the edge-type packet transfer device that accommodates the sending terminal determines the source address of the packet that caused the congestion included in the received congestion notification packet. And, as means for specifying the destination address, there is also means for specifying the header information of the higher-layer protocol based on the range of the header information to be referenced indicated in the congestion notification packet, and transfer of the packet corresponding to this specified information. The transfer restriction method, which is characterized by performing transfer restrictions. 6. An edge-type packet transfer device accommodating a receiving terminal in the transfer restriction method according to claim 3, when the congestion is detected, a plurality of packets causing the congestion are detected. The type of packet is extracted, and the priority of the congestion notification is determined by referring to the header information and the header information of the upper protocol for these packets, and the congestion notification packet is sent only to the source of the packet with the high priority of the congestion notification. A method of restricting transfer characterized by transmitting. 7. The transfer restriction method according to claim 3, wherein the edge-type packet transfer device accommodating the originating terminal restricts transmission based on the instruction content of the congestion notification packet. In addition, exclude those with a high transfer priority assigned to the packet to be transferred from the target of transmission restriction, and include only those with a low transfer priority assigned to the packet to be transferred as a target of transmission restriction. A transfer restriction method characterized by. 8. The transfer restriction method according to any one of claims 3 to 7, further comprising a packet discard means as a transfer restriction means performed by the edge-type packet transfer device accommodating the originating terminal. How to control transfer. 9. The transfer restriction method according to claim 3, wherein the edge-type packet transfer device accommodating the originating terminal reduces the packet transfer rate as a transfer restriction means. A transfer restriction method comprising: 10. The transfer restriction method according to any one of claims 3 to 7, wherein the edge-type packet transfer device accommodating the originating terminal is a means for restricting transfer.
A transfer regulation method comprising means for increasing or decreasing a transfer band according to the number of congestion notification packets received within a predetermined time. 11. The transfer restriction method according to claim 3, wherein the edge-type packet transfer device accommodating the calling terminal is a transfer restriction means.
It is characterized by having means for decreasing a transfer band by a fixed amount when a congestion notification packet is received within a predetermined time, and for increasing the transfer band by a fixed amount when a congestion notification packet is not received within a predetermined time period. Transfer restriction method. 12. The transfer restriction method according to claim 3, wherein the edge-type packet transfer device accommodating the originating terminal does not receive a congestion notification packet within a predetermined time. A transfer restriction method comprising means for canceling the transfer restriction.