WO2014141437A1

WO2014141437A1 - Communication node apparatus, band control method, and computer readable storage medium

Info

Publication number: WO2014141437A1
Application number: PCT/JP2013/057231
Authority: WO
Inventors: 瑞紀上原; 大橋　哲也
Original assignee: 株式会社日立製作所
Priority date: 2013-03-14
Filing date: 2013-03-14
Publication date: 2014-09-18

Abstract

A communication node apparatus connected to a first terminal for transferring data, which is transmitted from the first terminal, to a second terminal is characterized by: calculating, on the basis of a connection establishment request transmitted to the second terminal and a received connection establishment response, a first communication status value indicating the communication status of a connection before a start of transmission of user data; determining that a band control is to be implemented for the connection when it has been determined that the calculated first communication status value is greater than a first set value; and determining that no band control is to be implemented for the connection when it has been determined that the calculated first communication status value is equal to or less than the first set value.

Description

Communication node device, bandwidth control method, and computer-readable storage medium

The present invention relates to a communication node device that is connected to a terminal and transfers data transmitted from the terminal, and more particularly to a communication node device that performs bandwidth control of communication between terminals.

TCP (Transmission Control Protocol) is generally used for data communication between terminals in an IP (Internet Protocol) network that connects locations scattered all over the world.

In TCP, when the first terminal that transmits a data packet successfully reaches the second terminal that is the destination of the data packet, a confirmation response is returned from the second terminal to the first terminal. This ensures high communication reliability.

In the first terminal, the amount of data that can be transmitted from the start of data packet transmission until the first acknowledgment is received is limited, and this amount of data is referred to as the window size.

The first terminal determines that the network condition is good when the RTT (Round Trip Time) decreases and the packet discard rate decreases, increases the window size, and indirectly improves the effective bandwidth. However, if the RTT increases and the packet discard rate increases, the first terminal determines that the network condition has deteriorated, decreases the window size, and indirectly lowers the effective bandwidth. As described above, the RTT and the packet discard rate greatly influence the increase / decrease of the window size, and as a result, the effective bandwidth of the network is greatly influenced.

In recent years, relay devices that perform bandwidth control such as preventing an event that the effective bandwidth decreases due to an increase in the RTT or the packet discard rate and maintaining the effective bandwidth have been developed, and such relay devices are becoming popular. .

As a background art in such a technical field, there is JP 2012-124647 A (Patent Document 1). This gazette states that “the packet transmission side measures the retransmission bandwidth and performs packet transmission while performing bandwidth control based on the retransmission bandwidth, and the packet reception side detects the packet discard location and sends it to the transmission side. The function of performing feedback notification of the packet discard location, the function of performing packet retransmission based on the feedback notification at the packet transmission side, and the time of reaching a certain time defined as an interval at the packet reception side, The communication node device is characterized in that the available communication band on the packet transmission side is divided. ”

JP 2012-124647 A

The communication node device of Patent Document 1 determines whether or not to implement bandwidth control based on static information such as a destination IP address, a MAC address, and a port number. For this reason, since it is necessary for the administrator to set static information used for determining whether or not to perform bandwidth control in the communication node device, it is necessary to determine in advance a communication path for performing bandwidth control. For this purpose, the administrator needs to measure the network status and examine which communication path needs bandwidth control based on the network status.

Therefore, an object of the present invention is to provide a communication node device that can automatically determine a communication path for performing bandwidth control.

In order to solve the above problems, in the present invention, a communication node device is connected to a first terminal and transfers data transmitted from the first terminal to a second terminal, wherein the first terminal includes user data Before transmitting the user data, a connection establishment request, which is a request for establishing a connection used for transmission of the user data to the second terminal, is transmitted to the second terminal via the communication node device, and the second terminal When the connection establishment request is received, a connection establishment response that is a response to the connection establishment request is transmitted to the first terminal via the communication node device, and the first terminal sends the connection establishment response. After receiving, the user data is transmitted to the second terminal via the communication node device using the established connection, and the communication And a first communication device that calculates a first communication status value indicating a communication status of the connection before the start of transmission of the user data, based on the connection establishment request transmitted to the second terminal and the received connection establishment response. Then, it is determined whether or not the calculated first communication status value is greater than a first set value, and if it is determined that the calculated first communication status value is greater than the first set value, a bandwidth is applied to the connection. When it is determined that control is to be performed and it is determined that the calculated first communication status value is equal to or less than the first set value, it is determined that bandwidth control is not performed for the connection, and it is determined that the bandwidth control is to be performed. The bandwidth allocated to the connection is set larger than the bandwidth allocated to the connection determined not to perform the bandwidth control.

According to the present invention, it is possible to provide a communication node device that can automatically determine a communication path for performing bandwidth control.

Issues, configurations, and effects other than those described above will be clarified by the following description of the embodiments.

It is a block diagram which shows the structure of the relay system of Example 1 of this invention. It is a sequence diagram of the flow of the data between the 1st terminal of Example 1 of this invention, and a 2nd terminal. It is explanatory drawing of the connection management information of Example 1 of this invention. It is a flowchart of the RTT determination process of Example 1 of this invention. It is a flowchart of the discard rate registration process of Example 1 of this invention. It is a flowchart of the effective band registration process of Example 1 of this invention. It is a flowchart of the band control continuation determination process of Example 1 of the present invention. It is a flowchart of the setting value change process of Example 1 of this invention. It is explanatory drawing of the connection management information of Example 2 of this invention.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. For clarity of explanation, the following description and drawings are omitted and simplified as appropriate. Moreover, in each drawing, the same code | symbol is attached | subjected to the same element and the duplication description is abbreviate | omitted as needed for clarification of description.

Hereinafter, Example 1 will be described with reference to FIGS.

FIG. 1 is a block diagram showing the configuration of the relay system according to the first embodiment of the present invention.

The relay system includes a first terminal 101A, a second terminal 101B, and

communication node devices

100A and 100B.

Communication node devices

100A and 100B are collectively referred to as communication node device 100, and first terminal 101A and second terminal 101B are collectively referred to as terminal 101.

The first terminal 101A is a terminal that transmits a packet, and the second terminal 101B is a terminal that is a destination of the packet transmitted from the first terminal 101A, and receives the packet transmitted from the first terminal 101A.

The first terminal 101A is connected to the communication node device 100A via, for example, a LAN (Local Area Network). The communication node device 100A is connected to the communication node device 100B via a WAN (Wide Area Network). The communication node device 100B is connected to the second terminal 101B via a LAN, for example.

The communication node device 100 includes a TX unit (transmission unit) 102, an RX unit (reception unit) 103, connection management information 104, and a bandwidth control determination unit 105.

The TX unit 102 receives the packet transmitted from the first terminal 101A, and transmits the received packet to another communication node device 100 of the same type. The TX unit 102 receives a packet transmitted from another communication node device 100 of the same type, and transmits the received packet to the first terminal 101A.

In the connection management information 104, information related to a connection for which bandwidth control is performed among the connections established between the communication node devices 100 is registered. The connection management information 104 will be described in detail with reference to FIG. The bandwidth control determination unit 105 refers to the connection management information 104 and determines whether to perform bandwidth control on the connection. A connection in which bandwidth control is performed is assigned a larger bandwidth than a connection in which bandwidth control is not performed.

The TX unit 102 includes a transmission packet input processing unit 106, a transmission bandwidth control unit 107, and a transmission packet output processing unit 108.

The transmission packet input processing unit 106 receives the packet transmitted from the first terminal 101A, performs predetermined input processing on the received packet, and outputs the packet to the transmission bandwidth control unit 107.

Based on the determination result of the bandwidth control determination unit 105, the transmission bandwidth control unit 107 controls the bandwidth of the connection that transmits the packet input from the transmission packet input processing unit 106, and sends the packet to the transmission packet output processing unit 108. Output. Further, the transmission bandwidth control unit 107 adds a new entry to the connection management information 104 or deletes an entry registered in the connection management information based on the packet to be transmitted.

The transmission packet output processing unit 108 performs a predetermined output process on the packet input from the transmission band control unit 107 and transmits the packet to the WAN. The transmission packet output processing unit 108 registers information in the connection management information 104 based on the packet to be transmitted.

The RX unit 103 includes a received packet input processing unit 109 and a received packet output processing unit 110.

The received packet input processing unit 109 receives the ACK packet transmitted from the second terminal 101B, performs predetermined input processing on the received packet, and outputs the packet to the received packet output processing unit 110.

The received packet output processing unit 110 performs a predetermined output process on the packet input from the received packet input processing unit 109, and outputs the packet to the first terminal 101A.

Next, communication processing between the first terminal 101A and the second terminal 101B will be described with reference to FIG. FIG. 2 is a sequence diagram of communication processing between the first terminal 101A and the second terminal 101B according to the first embodiment of this invention.

First, before transmitting a data packet, the first terminal 101A transmits a SYN packet (connection establishment request), which is a connection establishment request, to the communication node device 100A in order to establish a connection used for transmitting the data packet. (301).

When the communication node device 100A receives the SYN packet transmitted from the first terminal 101A, the communication node device 100A transmits the received SYN packet to the communication node device 100B (302).

When the communication node device 100B receives the SYN packet transmitted from the communication node device 100B, the communication node device 100B transmits the received SYN packet to the second terminal 101B (303).

When the second terminal 101B receives the SYN packet transmitted from the communication node device 100B, the second terminal 101B transmits a SYN-ACK packet (connection establishment response) that is an ACK to the received SYN packet to the communication node device 100B (304).

When the communication node device 100B receives the SYN-ACK packet transmitted from the second terminal 101B, the communication node device 100B transmits the received SYN-ACK packet to the communication node device 100A (305).

If the communication node device 100A receives the SYN-ACK packet transmitted from the communication node device 100B, the communication node device 100A transmits the received SYN-ACK packet to the first terminal 101A (306). Also, the communication node device 100A calculates an RTT (Round Trip Time) based on the transmission time of the SYN packet and the reception time of the SYN-ACK packet, and based on the calculated RTT, the bandwidth for the connection used for transmitting the data packet RTT determination processing for determining whether or not to execute control is executed, and the determination result is set in the connection (307). The RTT determination process will be described in detail with reference to FIG.

When the first terminal 101A receives the SYN-ACK packet transmitted from the communication node device 100A, the first terminal 101A transmits an ACK packet, which is an ACK to the received SYN-ACK packet, to the communication node device 100A (308).

When receiving the ACK packet transmitted from the first terminal 101A, the communication node device 100A includes the determination result of the RTT determination process in the received ACK packet and transmits the ACK packet to the communication node device 100B (309). Thereby, the communication node device 100A can notify the determination result of the RTT determination processing to the communication node device 100B.

When the communication node device 100B receives the ACK packet transmitted from the communication node device 100A, the communication node device 100B transmits the received ACK packet to the second terminal 101B (310).

By the above 301 to 310, a connection is established between the first terminal 101A and the second terminal 101B, and the communication node device 100A determines the communication status at the time of connection establishment before data packet (user data) transmission. It can be determined whether or not to perform bandwidth control on the connection.

The first terminal 101A transmits an ACK packet of the SYN-ACK packet, and then transmits a data packet to the communication node device 100A (311).

When the communication node device 100A receives the data packet transmitted from the first terminal 101A, the communication node device 100A transmits the received data packet to the communication node device 100B (312). In addition, when bandwidth control is performed on the connection used for data packet transmission, the communication node device 100A sets the discard rate based on the number of data packet transmissions in the connection and the number of data packet retransmissions in the connection. A discard rate registration process for calculating and registering the calculated discard rate in the connection management information 104 is executed (314). The discard rate registration process will be described in detail with reference to FIG. In the present embodiment, (data packet retransmission number) / (data packet transmission number) is used as the discard rate, but it is not particularly limited to this definition.

When the communication node device 100B receives the data packet transmitted from the communication node device 100A, the communication node device 100B transmits the received data packet to the second terminal 101B (313).

When the second terminal 101B receives the data packet transmitted from the communication node device 100B, the second terminal 101B transmits an ACK packet (user data response) that is an ACK to the received data packet to the communication node device 100B (315).

When the communication node device 100B receives the ACK packet transmitted from the second terminal 101B, the communication node device 100B transmits the received ACK packet to the communication node device 100A (316).

When receiving the ACK packet transmitted from the communication node device 100B, the communication node device 100A transmits the received ACK packet to the first terminal 101A (317). When the bandwidth control is performed on the connection used for transmitting the data packet, the communication node device 100A calculates the effective bandwidth of the connection and registers the calculated effective bandwidth in the connection management information 104. The process is executed (318). The effective bandwidth registration process will be described in detail with reference to FIG.

The communication node device 100A executes a bandwidth control continuation determination process for determining whether to continue or stop the bandwidth control of the connection based on the discard rate and effective bandwidth of the connection for which the bandwidth control is performed (319). . The bandwidth control continuation determination process is a process executed by the communication node device 100A at a predetermined cycle, and will be described in detail with reference to FIG.

The first terminal 101A transmits a data packet to the communication node device 100A (320).

When the communication node device 100A receives the data packet transmitted from the first terminal 101A, the communication node device 100A transmits the received data packet to the communication node device 100B (321). If the communication node device 100A determines in the bandwidth control determination process executed immediately before that the bandwidth control of the connection used for transmission of the data packet is to be stopped, the communication node device 100A adds the bandwidth control of the connection to the received data packet. The data packet is transmitted to the communication node device 100B including the fact that the execution is stopped. Thereby, the communication node device 100A can notify the communication node device 100B that the band control is to be stopped.

Since the subsequent processing is the same as the above-described processing 313 to 319, the same reference numerals are given and description thereof is omitted.

As shown in FIG. 2, the communication node device 100A performs bandwidth control on the connection based on the value (first communication status value) indicating the communication status of the connection at the time of establishing the connection before the data packet is transmitted. Therefore, it is possible to automatically determine whether or not to perform bandwidth control without bothering the administrator.

Here, the communication node device of Patent Document 1 cannot stop the bandwidth control during the communication, and cannot release the resources of the device and the network until the communication is completed. For this reason, even if communication with a worse network condition than communication for which bandwidth control is performed is started, bandwidth control may not be performed due to resource depletion in the communication, and resources cannot be optimally distributed. . Therefore, the communication node device 100A according to the present embodiment calculates the discard rate of the connection when the data packet received from the first terminal 101A is transmitted to the communication node device 100B, and the connection when the ACK packet for the data packet is received. The effective bandwidth is calculated, and based on these discard rates and effective bandwidths, it is determined in a predetermined cycle whether to continue or stop the bandwidth control. As a result, it is possible to stop the bandwidth control of the connection in which the communication state is good, release the network resources, and optimally distribute the network resources. The discard rate and the effective bandwidth are values (second communication status values) indicating the communication status of the connection during transmission of user data.

FIG. 3 is an explanatory diagram of the connection management information 104 according to the first embodiment of this invention.

The connection management information 104 is for managing connections determined to be subjected to bandwidth control. The connection ID 201, the SYN packet transmission time 202, the SYN-ACK packet reception time 203, the RTT 204, the transmission number 205, and the retransmission number 206. , Discard rate 207, and effective bandwidth 208.

In the connection ID 201, a unique identifier of the connection is registered. In the SYN packet transmission time 202, the time when the communication node device 100 transmits the SYN packet is registered. In the SYN-ACK packet reception time 203, the time at which the communication node device 100 received the SYN-ACK packet is registered. Registered in the RTT 204 is a time obtained by subtracting the time registered at the SYN packet transmission time 202 from the time registered at the SYN-ACK packet reception time 203.

In the transmission number 205, the number of data packets transmitted using the connection identified by the identifier registered in the connection ID 201 is registered. In the number of retransmissions 206, the number of data packets that need to be retransmitted in the connection identified by the identifier registered in the connection ID 201 is registered. In the discard rate 207, the ratio of the number of discarded data packets to the number registered in the transmission number 205 is registered. Specifically, a value obtained by dividing the number registered in the number of retransmissions 206 by the number registered in the number of transmissions 205 is registered in the discard rate 207.

In the effective band 208, the effective band of the WAN connecting the communication node device 100A and the communication node device 100B is registered.

FIG. 4 is a flowchart of the RTT determination process according to the first embodiment of the present invention.

In the RTT determination process, when the communication node device 100A receives the SYN packet transmitted from the first terminal 101A, a program for the RTT determination process is read from a storage area (not shown) and executed by a processor (not shown).

When the transmission packet input processing unit 106 receives the SYN packet transmitted from the first terminal 101A, the received SYN packet is input to the transmission bandwidth control unit 107, and the transmission bandwidth control unit 107 transmits the input SYN packet. Transmission is performed toward the second terminal 101B via the packet output processing unit 108 (401).

In addition, when a SYN packet is input from the transmission packet input processing unit 106, the transmission bandwidth control unit 107 adds a new entry to the connection management information 104, and transmits the SYN packet at the SYN packet transmission time 202 of the added entry. The registered time is registered (402).

Next, when the received packet input processing unit 109 receives the SYN-ACK packet transmitted from the second terminal 101B via the communication node device 100B, the received SYN-ACK packet is input to the received packet output processing unit 110. The received packet output processing unit 110 transmits the input SYN-ACK packet to the first terminal 101A (403).

When receiving the SYN-ACK packet, the received packet input processing unit 109 receives the SYN-ACK packet at the SYN-ACK packet reception time 203 of the entry corresponding to the received SYN-ACK packet in the connection management information 104. The registered time is registered (404).

When the reception time of the SYN-ACK packet is registered in the SYN-ACK packet reception time 203 of the connection management information 104, the bandwidth control determination unit 105 refers to the connection management information 104 and corresponds to the received SYN-ACK packet. The RTT is calculated by subtracting the time registered at the SYN packet transmission time 202 from the time registered at the SYN-ACK packet reception time 203 of the entry, and the calculated RTT is registered in the RTT 204 of the entry (405). . Then, the bandwidth control determination unit 105 determines whether or not the RTT calculated in the process of step 405 is larger than the set value (406).

If it is determined that the calculated RTT is greater than the set value, the bandwidth control determination unit 105 determines that bandwidth control is to be performed on the connection established by the SYN packet, maintains the entry (407), and performs the processing in step 409. The process is transferred to.

On the other hand, when it is determined that the calculated RTT is equal to or less than the set value, the bandwidth control determination unit 105 determines that bandwidth control is not performed on the connection established by the SYN packet, and deletes the entry (408). The process proceeds to the process of step 409.

After execution of the processing in step 407 or 408, the bandwidth control determination unit 105 changes the setting value used in the RTT determination processing and the setting value used in the bandwidth control execution continuation determination processing based on the number of connections for which bandwidth control is performed. The set value changing process is executed (409), and the process is terminated. The set value changing process will be described in detail with reference to FIG.

As described above, it is determined whether or not to perform bandwidth control on the connection based on the communication status of the connection at the time of establishing the connection before transmitting the data packet. Accordingly, it is not necessary for the administrator to determine in advance whether or not to perform bandwidth control, and communication for bandwidth control can be determined without bothering the administrator.

FIG. 5 is a flowchart of the discard rate registration process according to the first embodiment of the present invention.

When the communication node device 100A receives the data packet transmitted from the first terminal 101A, the discard rate registration process is executed by a processor (not shown) by reading a program for the discard rate registration process from a storage area (not shown). The

When the transmission packet input processing unit 106 receives a data packet transmitted from the first terminal 101A, the received data packet is input to the transmission band control unit 107, and the transmission band control unit 107 transmits the input data packet. Transmission is performed toward the second terminal 101B via the packet output processing unit 108 (501). If it is determined that the connection used for data packet transmission stops the bandwidth control in the bandwidth control continuation determination process executed immediately before, the communication node device 100A performs the bandwidth control of the connection. A message to stop is included in the data packet and transmitted.

Next, the bandwidth control determination unit 105 determines whether or not an entry corresponding to the connection used for transmitting the data packet is registered in the connection management information 104, so that the bandwidth control is performed on the connection. It is determined whether or not (502). In the process of step 502, when it is determined that an entry corresponding to the connection used for transmitting the data packet is registered, it is determined that bandwidth control is performed for the connection, and the transmission of the data packet is performed. If it is determined that the entry corresponding to the used connection is not registered, it is determined that bandwidth control is not performed for the connection.

If it is determined in step 502 that the entry corresponding to the connection used for data packet transmission is not registered in the connection management information 104, the bandwidth control determination unit 105 ends the discard rate registration process.

On the other hand, if it is determined in step 502 that the entry corresponding to the connection used for data packet transmission is registered in the connection management information 104, the transmission packet output processing unit 108 The entry transmission number 205 used to transmit the data packet is updated to the number of transmitted data packets, and the retransmission number 206 of the entry is updated to the number of data packets that require retransmission (503).

When the number of data packets is registered in the number of transmissions 205 and the number of retransmissions 206 of the connection management information 104, the bandwidth control determination unit 105 refers to the connection management information 104 and enters an entry corresponding to the connection used to transmit the data packet. The data packet discard rate is calculated by dividing the number of data packets registered in the retransmission number 206 by the number of data packets registered in the transmission number 205, and the discard rate calculated as the discard rate 207 of the entry. Is registered (504), and the process is terminated.

FIG. 6 is a flowchart of the effective bandwidth registration process according to the first embodiment of the present invention.

In the effective bandwidth registration process, when the communication node device 100A receives an ACK packet as a response to the data packet from the communication node device 100B, the effective bandwidth registration processing program is read from a storage area (not shown) and is not shown. Executed by the processor.

When receiving the ACK packet transmitted from the second terminal 101B via the communication node device 100B, the received packet input processing unit 109 inputs the received ACK packet to the received packet output processing unit 110, and receives the received packet output processing unit 110. Transmits the input ACK packet to the first terminal 101A (601).

The bandwidth control determination unit 105 determines whether or not bandwidth control is performed for the connection by determining whether or not an entry corresponding to the received ACK packet is registered in the connection management information 104 (602). ). The entry corresponding to the received ACK packet is an entry corresponding to the connection used for transmitting the data packet corresponding to the received ACK packet.

In step 602, if it is determined that an entry corresponding to the received ACK packet is registered in the connection management information 104, it is determined that bandwidth control is performed for the connection, and the received ACK packet If it is determined that the corresponding entry is not registered in the connection management information 104, it is determined that bandwidth control is not performed for the connection.

If it is determined in step 602 that the entry corresponding to the received ACK packet is not registered in the connection management information 104, the bandwidth control determination unit 105 ends the effective bandwidth registration processing.

On the other hand, if it is determined in step 602 that the entry corresponding to the received ACK packet is registered in the connection management information 104, the received packet input processing unit 109 receives the received packet based on the received ACK packet. The effective bandwidth of the connection used for transmission of the data packet corresponding to the ACK packet is calculated (603), and the calculated effective bandwidth is registered in the effective bandwidth 208 of the entry corresponding to the connection management information 104 (604).

Specifically, the reception packet input processing unit 109 calculates the delay time of the data packet by subtracting the transmission time of the data packet corresponding to the ACK packet from the reception time of the ACK packet. Then, the received packet input processing unit 109 calculates the effective bandwidth of the connection used for transmitting the data packet by dividing the capacity of the data packet by the calculated delay time. In this embodiment, the effective bandwidth is calculated by the above-described method, but the present invention is not particularly limited to this method.

FIG. 7 is a flowchart of the bandwidth control continuation determination process executed in a predetermined cycle according to the first embodiment of the present invention. In the bandwidth control continuation determination process, a program for bandwidth control continuation determination processing is read from a storage area (not shown) at a predetermined cycle, and is executed by a processor (not shown).

First, the bandwidth control determination unit 105 selects an entry to be processed from the connection management information 104 (701).

Next, the bandwidth control determination unit 105 acquires the values of the discard rate 207 and the effective bandwidth 208 of the entry to be processed in the connection management information 104 (702).

Then, the bandwidth control determination unit 105 determines whether or not the discard rate acquired in step 702 is greater than a set value (703).

If it is determined in step 703 that the discard rate acquired in step 702 is equal to or less than the set value, the bandwidth control determination unit 105 determines to stop performing bandwidth control for the connection of the entry to be processed, The entry to be processed is deleted from the connection management information 104 (706), and the process proceeds to step 707.

On the other hand, if it is determined that the discard rate acquired in step 702 is greater than the set value, the bandwidth control determination unit 105 determines whether the effective bandwidth acquired in step 702 is greater than the set value ( 704).

When it is determined in step 704 that the effective bandwidth acquired in step 702 is equal to or less than the set value, the bandwidth control determination unit 105 shifts the processing to step 706 and starts processing from the connection management information 104. Is deleted, and the process proceeds to step 707.

On the other hand, if it is determined in step 704 that the effective bandwidth acquired in step 702 is larger than the set value, the bandwidth control determination unit 105 determines to continue the bandwidth control of the connection of the entry to be processed. Then, the processing target entry of the connection management information 104 is maintained (705), and the processing shifts to the processing of step 707.

After execution of the processing in

step

705 or 706, the bandwidth control determination unit 105 determines whether all entries of the connection management information 104 have been selected as processing target entries (707).

If it is determined in step 707 that all entries of the connection management information 104 have been acquired as processing target entries, the bandwidth control determination unit 105 executes setting value change processing (708) and ends the processing. . The set value change process is the same as the process in step 409 of the RTT determination process shown in FIG.

On the other hand, if it is determined in step 707 that all the entries in the connection management information 104 have been acquired as processing target entries, the bandwidth control determination unit 105 proceeds to the process in step 701, An entry that has not yet been selected as a processing target entry is selected as a new processing target entry.

Based on the above, based on the communication status during data packet transmission of the connection used for data packet transmission, it is determined whether to continue or stop the bandwidth control for the connection. As a result, even if the connection is determined to be subjected to bandwidth control in the RTT determination processing, if the communication status is good thereafter, the bandwidth control is stopped, so network resources are released, Network resources can be optimally distributed.

In the bandwidth control determination process shown in FIG. 7, the communication node device 100A performs the bandwidth control of the connection when the discard rate of the connection is equal to or lower than the set value or when the effective bandwidth of the connection is equal to or lower than the set value. When the connection discard rate is greater than the set value and the effective bandwidth of the connection is greater than the set value, it is determined that the connection bandwidth control is to be continued. However, the determination whether to continue or stop the bandwidth control of the connection is not limited to this. For example, the communication node device 100A determines that the connection bandwidth control is to be stopped when the connection discard rate is less than or equal to the set value and the effective bandwidth of the connection is less than or equal to the set value. If it is greater than the set value, or if the effective bandwidth of the connection is greater than the set value, it may be determined that the connection bandwidth control is to be continued. Also, the communication node device 100A may determine whether to continue or stop the bandwidth control of the connection using only either the discard rate or the effective bandwidth.

FIG. 8 is a flowchart of the setting value changing process according to the first embodiment of the present invention.

The set value change process is executed in the RTT determination process and the band control continuation determination process.

First, the bandwidth control determination unit 105 refers to the connection management information 104 and totals the number of entries registered in the connection management information 104, thereby acquiring the number of connections for which bandwidth control is performed (801). ).

Next, the bandwidth control determination unit 105 determines whether or not the number of connections for which bandwidth control acquired in the process of Step 801 is performed is greater than a predetermined value (802).

If the number of connections for which bandwidth control acquired in step 801 is being executed is greater than a predetermined value, the bandwidth control determination unit 105 determines the setting value used in the RTT determination processing, Then, the set value of the discard rate and the set value of the effective band used in the band control continuation determination process are set to predetermined first values (803), and the process ends.

On the other hand, when it is determined in the process of step 802 that the number of connections for which the bandwidth control acquired in the process of step 801 is implemented is equal to or less than a predetermined value, the band control determination unit 105 sets the settings used in the RTT determination process The value, the set value of the discard rate used in the band control continuation determination process, and the set value of the effective band are set to a second value smaller than the first value (804), and the process ends.

When the number of connections for which bandwidth control is performed increases, bandwidth control may not be performed for all connections in the WAN bandwidth between the

communication node devices

100A and 100B. Therefore, in the setting value changing process of the present embodiment, when the number of connections for which bandwidth control is performed is greater than a predetermined number, the setting value used for the RTT determination process and the bandwidth control continuation determination process is the connection value for which the bandwidth control is performed. The number is set to a larger value than when the number is a predetermined number or less. Accordingly, it is difficult to determine that the band control is newly performed in the RTT determination process, and it is easy to determine that the band control is to be stopped in the band control continuation determination rule. Therefore, bandwidth control can be reliably performed on the connection in the WAN bandwidth.

Hereinafter, Example 2 of the present invention will be described with reference to FIG.

In the bandwidth control continuation determination process according to the first embodiment, it is determined whether to continue or stop the bandwidth control for the connection for which the bandwidth control is performed. Whether or not to perform bandwidth control is determined not only for connections in which bandwidth control is performed but also for connections for which bandwidth control is not performed.

FIG. 9 is an explanatory diagram of the connection management information 111 according to the second embodiment of this invention. The same configuration as the connection management information 104 shown in FIG. 3 of the first embodiment in the connection management information 111 shown in FIG.

The connection management information 104 according to the first embodiment manages information related to connections for which bandwidth control is performed, while the connection management information 111 according to the second embodiment also manages information regarding connections for which bandwidth control is not performed.

The connection management information 111 includes a connection ID 201, a SYN packet transmission time 202, a SYN-ACK packet reception time 203, an RTT 204, a transmission number 205, a retransmission number 206, a discard rate 207, an effective bandwidth 208, and a bandwidth control 209.

In the bandwidth control 209, information indicating whether bandwidth control is performed on the connection used for transmitting the data packet is registered.

Next, the RTT determination process of the present embodiment will be described with reference to FIG.

The processes of steps 407 and 408 of the RTT determination process of the present embodiment are different from the RTT determination process of the first embodiment, and other processes are the same as the RTT determination process of the first embodiment.

In the process of step 407, the bandwidth control determination unit 407 is established by the SYN packet among the entries of the connection management information 111 when it is determined in the process of step 406 that the RTT calculated in the process of step 405 is larger than the set value. The validity is registered in the bandwidth control 209 of the entry corresponding to the connected connection, and the processing shifts to the processing in step 409.

In the process of step 408, the bandwidth control determination unit 407 determines that the RTT calculated in the process of step 405 is equal to or less than the set value by the process of step 406 by using the SYN packet among the entries of the connection management information 111. Invalidity is registered in the bandwidth control 209 of the entry corresponding to the established connection, and the process proceeds to the process of step 409.

Next, the discard rate registration process of this embodiment will be described with reference to FIG.

The discard rate registration process of the present embodiment is different from the discard rate registration process of the first embodiment in that the process of step 502 is not executed, and the other processes are the same as the discard rate registration process of the first embodiment.

In the discard rate registration process according to the present embodiment, since the process of step 502 is not executed, the number of transmissions 205 of the connection management information 111, regardless of whether bandwidth control is performed on the connection used for transmitting the data packet, The number of retransmissions 206 and the discard rate 207 are updated.

Next, the effective bandwidth registration process of the present embodiment will be described with reference to FIG.

The effective bandwidth registration process of the present embodiment is different from the effective bandwidth registration process of the first embodiment in that the process of step 602 is not executed, and the other processes are the same as the effective bandwidth registration process of the first embodiment.

In the effective bandwidth registration processing of this embodiment, since the processing of step 602 is not executed, connection management is performed regardless of whether bandwidth control is performed on the connection used for transmitting the data packet corresponding to the received ACK packet. The effective bandwidth 208 of the information 111 is updated.

Next, the bandwidth control continuation determination process of this embodiment will be described with reference to FIG.

In the bandwidth control continuation determination process according to the present embodiment, whether the communication node device 100A performs bandwidth control based on the communication status of the connection during data packet communication regardless of whether bandwidth control is performed. Determine whether or not.

The processing of

steps

705 and 706 of the bandwidth control continuation determination process of the present embodiment is different from the bandwidth control continuation determination processing of the first embodiment, and the other processing is the same as the bandwidth control continuation determination processing of the first embodiment.

If it is determined in step 704 that the effective bandwidth acquired in step 702 is greater than the set value, the bandwidth control determination unit 105 determines that bandwidth control is to be performed on the connection of the entry to be processed, and connection management information The validity is registered in the bandwidth control 209 of the processing target entry 111, and the process proceeds to the process in step 707.

If it is determined in step 703 that the discard rate acquired in step 702 is less than or equal to the set value, or if the effective bandwidth acquired in step 702 is less than or equal to the set value in step 704 If so, the bandwidth control determination unit 105 determines that the bandwidth control is not performed for the connection of the processing target entry, registers invalidity in the bandwidth control 209 of the processing target entry of the connection management information 111, and performs the processing of step 707 The process is transferred to.

When the communication node device 100A receives the data packet transmitted using the connection corresponding to the entry of the connection management information 111 in which the bandwidth control 209 is changed from valid to invalid in the bandwidth control continuation determination process, The fact that continuation is to be stopped is included in the data packet and transmitted to communication node device 100B. When the communication node device 100A receives a data packet transmitted using a connection corresponding to the entry of the connection management information 111 in which the bandwidth control 209 is changed from invalid to valid in the bandwidth control continuation determination process, the communication node device 100A performs bandwidth control. The start is included in the data packet and transmitted to the communication node device 100B.

Next, the setting value changing process of this embodiment will be described with reference to FIG.

The processing of step 801 in the setting value changing process of the present embodiment is different from the setting value changing process of the first embodiment, and the other processes are the same as the setting value changing process of the first embodiment.

In the processing of step 801, the bandwidth control determination unit 105 refers to the connection management information 111, and performs bandwidth control by summing the number of entries registered as valid in the bandwidth control 209 of the connection management information 111. Get the number of open connections.

As described above, even if it is determined that the bandwidth control is not performed once, it is determined that the bandwidth control is performed according to the network status of the connection. For this reason, it is possible to perform bandwidth control for a connection whose communication status is worse than that at the start of communication, and to suppress the delay time until the data packet transmitted by the first terminal 101A arrives at the second terminal 101B. it can.

Similarly to the first embodiment, even if it is determined that the bandwidth control is once performed, it is determined that the bandwidth control is stopped according to the network status of the connection. For this reason, network resources are released, and network resources can be optimally distributed.

In addition, this invention is not limited to the above-mentioned Example, Various modifications are included. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of a certain embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of a certain embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

In addition, each of the above-described configurations, functions, processing units, processing means, and the like may be realized by hardware by designing a part or all of them with, for example, an integrated circuit. Each of the above-described configurations, functions, and the like may be realized by software by interpreting and executing a program that realizes each function by the processor. Information such as programs, tables, and files that realize each function can be stored in a recording device such as a memory, a hard disk, and an SSD (Solid State Drive), or a recording medium such as a CI card, an SD card, and a DVD.

Claims

A communication node device connected to a first terminal and transferring data transmitted from the first terminal to a second terminal,
Before transmitting user data, the first terminal sends a connection establishment request, which is a request for establishing a connection used for transmitting the user data to the second terminal, via the communication node device. To
When the second terminal receives the connection establishment request, the second terminal transmits a connection establishment response, which is a response to the connection establishment request, to the first terminal via the communication node device,
The first terminal, after receiving the connection establishment response, transmits the user data to the second terminal via the communication node device using the established connection,
The communication node device is:
Based on the connection establishment request transmitted to the second terminal and the received connection establishment response, a first communication status value indicating a communication status of the connection before starting transmission of the user data is calculated,
Determining whether the calculated first communication status value is greater than a first set value;
When it is determined that the calculated first communication status value is greater than the first setting value, it is determined that bandwidth control is performed on the connection,
A communication node device characterized in that a bandwidth allocated to a connection determined to implement the bandwidth control is made larger than a bandwidth allocated to a connection determined not to implement the bandwidth control.
The communication node device according to claim 1,
When the second terminal receives the user data, the second terminal transmits a user data response, which is a response to the user data, to the first terminal via the communication node device,
The communication node device is:
A second communication status value indicating a communication status during transmission of the user data of a connection used for transmission of the user data based on at least one of the user data transmitted to the second terminal and the received user data response To calculate
Determining whether the calculated second communication status value is greater than a second set value;
When it is determined that the calculated second communication status value is greater than the second setting value, it is determined that bandwidth control is performed on the connection,
When it is determined that the calculated second communication status value is equal to or less than the second set value, it is determined that bandwidth control is not performed for the connection.
The communication node device according to claim 2,
Calculating the second communication status value of the connection determined to implement the bandwidth control;
When it is determined that the calculated second communication status value is greater than the second setting value, it is determined that the bandwidth control is to be continued for the connection;
When it is determined that the calculated second communication status value is equal to or less than the second set value, it is determined that the bandwidth control for the connection is to be stopped.
The communication node device according to claim 2,
The first setting value and the second setting value when the number of connections determined to implement the bandwidth control is greater than a predetermined value, and the number of connections determined to implement the bandwidth control is equal to or less than the predetermined value. A communication node device that is set to a value larger than the first setting value and the second setting value in a case.
The communication node device according to claim 2,
When the user data transmitted from the first terminal is transmitted to the second terminal, the total number of user data transmitted in the connection used for transmitting the received user data and the user data required to be retransmitted The communication node device calculates a discard rate of user data of the connection as the second communication status value based on the total number of the communication nodes.
The communication node device according to claim 2,
When the user data response is received from the second terminal, a transmission time of user data corresponding to the received user data response is subtracted from a reception time of the user data response, and a delay time of the user data is calculated,
Calculating the effective bandwidth of the connection used for transmitting the user data as the second communication status value based on the capacity of the user data transmitted to the second terminal and the calculated delay time of the user data. A characteristic communication node device.
The communication node device according to claim 1,
When the connection establishment response is received, a value obtained by subtracting the connection establishment request transmission time corresponding to the connection establishment response from the reception time of the connection establishment response is calculated as the first communication status value. Communication node device.
A bandwidth control determination method for determining whether or not to implement bandwidth control in a communication node device connected to a first terminal and transferring data transmitted from the first terminal to a second terminal,
Before transmitting user data, the first terminal sends a connection establishment request, which is a request for establishing a connection used for transmitting the user data to the second terminal, via the communication node device. To
When the second terminal receives the connection establishment request, the second terminal transmits a connection establishment response, which is a response to the connection establishment request, to the first terminal via the communication node device,
The first terminal, after receiving the connection establishment response, transmits the user data to the second terminal via the communication node device using the established connection,
The method
The communication node device, based on the connection establishment request transmitted to the second terminal and the received connection establishment response, has a first communication status value indicating a communication status of the connection before the start of transmission of the user data. Calculate
The communication node device determines whether the calculated first communication status value is greater than a first set value;
The communication node device determines to perform bandwidth control on the connection when the calculated first communication status value is determined to be larger than the first set value;
The communication node device makes a bandwidth allocated to a connection determined to implement the bandwidth control larger than a bandwidth allocated to a connection determined not to implement the bandwidth control.
The bandwidth control determination method according to claim 8, wherein
When the second terminal receives the user data, the second terminal transmits a user data response, which is a response to the user data, to the first terminal via the communication node device,
The method
The communication node device indicates a communication status during transmission of the user data of a connection used for transmission of the user data based on at least one of user data transmitted to the second terminal and a received user data response. 2 Calculate the communication status value,
The communication node device determines whether the calculated second communication status value is greater than a second set value;
The communication node device, when it is determined that the calculated second communication status value is larger than the second setting value, determines to perform bandwidth control on the connection,
The communication node device, when it is determined that the calculated second communication status value is equal to or less than the second set value, determines that bandwidth control is not performed for the connection.
The bandwidth control determination method according to claim 9,
The communication node device calculates the second communication status value of the connection determined to implement the bandwidth control;
The communication node device, when it is determined that the calculated second communication status value is larger than the second setting value, determines to continue the bandwidth control for the connection,
The communication node device, when it is determined that the calculated second communication status value is equal to or less than the second set value, determines to stop performing bandwidth control on the connection. .
The bandwidth control determination method according to claim 9,
The communication node device uses the first setting value and the second setting value when the number of connections determined to implement the bandwidth control is greater than a predetermined value, and the number of connections determined to implement the bandwidth control. A bandwidth control determination method characterized by setting a value larger than the first set value and the second set value when the value is equal to or less than the predetermined value.
The bandwidth control determination method according to claim 9,
When the communication node device transmits the user data transmitted from the first terminal to the second terminal, the total number of user data transmitted in the connection used for transmission of the received user data and retransmission are necessary. A bandwidth control determination method, comprising: calculating a discard rate of user data of the connection as the second communication status value based on the total number of user data that has become.
The bandwidth control determination method according to claim 9,
When the communication node device receives the user data response from the second terminal, the communication node device subtracts a transmission time of user data corresponding to the received user data response from a reception time of the user data response, and Calculate the delay time,
The communication node device determines the effective bandwidth of the connection used for transmitting the user data based on the capacity of the user data transmitted to the second terminal and the calculated delay time of the user data. A bandwidth control determination method characterized by calculating as a value.
The bandwidth control determination method according to claim 8, wherein
When the communication node apparatus receives the connection establishment response, the communication node apparatus subtracts a value obtained by subtracting the connection establishment request transmission time corresponding to the connection establishment response from the connection establishment response reception time. A bandwidth control determination method characterized by calculating as follows.
A process connected to the first terminal, transferring the data transmitted from the first terminal to the second terminal, executed in a communication node device having a processor and a storage area, and determining whether or not to implement bandwidth control A computer-readable storage medium for storing a program to be executed by the processor,
Before transmitting user data, the first terminal sends a connection establishment request, which is a request for establishing a connection used for transmitting the user data to the second terminal, via the communication node device. To
When the second terminal receives the connection establishment request, the second terminal transmits a connection establishment response, which is a response to the connection establishment request, to the first terminal via the communication node device,
The first terminal, after receiving the connection establishment response, transmits the user data to the second terminal via the communication node device using the established connection,
The process is
Based on the connection establishment request transmitted to the second terminal and the received connection establishment response, a first communication status value indicating a communication status of the connection before starting transmission of the user data is calculated,
Determining whether the calculated first communication status value is greater than a first set value;
When it is determined that the calculated first communication status value is greater than the first setting value, it is determined that bandwidth control is performed on the connection,
When it is determined that the calculated first communication status value is equal to or less than the first set value, it is determined that bandwidth control is not performed on the connection,
A computer-readable storage medium, wherein a bandwidth allocated to a connection determined to implement the bandwidth control is made larger than a bandwidth allocated to a connection determined not to implement the bandwidth control.