WO2015186332A1 - Transmission data amount control apparatus, control system, control method and control program - Google Patents

Abstract

The objective of the invention is to achieve a network in which the amount of packets to be sent out is appropriately controlled in accordance with a network condition, such as transmission buffer amount, to suppress the halt of sending out the packets, thereby improving the user experience quality. A transmission data amount control apparatus of the invention comprises: a transmission upper-limit data amount calculation means that sets an upper-limit value of a simultaneous transmission data amount on the basis of information based on acknowledgement packets, a data packet amount and a simultaneous transmission data amount history in transmission/reception of data packets using TCP; and a transmission data amount limitation means that outputs, on the basis of the upper-limit value, a control signal to limit the simultaneous transmission data amount.

Description

Transmission data amount control device, control system, control method, and control program

The present invention relates to a network technology, and more particularly to a network technology for transmitting and receiving data packets using TCP (Transmission Control Protocol).

In recent years, along with the increase in the line capacity of the Internet and the development of communication technology that handles a variety of media information, it has become possible to enjoy rich media information delivery anytime and anywhere from mobile terminals. Such lifestyles have become widespread, and mobile communication technologies such as LTE (Long Term Evolution) and LTE-A (LTE Advanced) are spreading as high-speed mobile environments that support the information distribution.

In a high-speed mobile communication environment such as LTE, a large-capacity buffer is provided in an LTE radio base station such as eNodeB in order to absorb the influence of band fluctuation in a radio section. In addition, when a bit error occurs in the radio section, retransmission is performed in the lower layer by ARQ (Automatic Repeat reQuest) technology in the RLC (Radio Link Control) layer and HARQ (Hybrid ARQ) technology in the MAC (Media Access Control) layer. Repair the data. For this reason, packet corruption hardly occurs in layers higher than the network layer.

On the other hand, TCP, which is a transport layer protocol widely used for both wired and wireless data communication, determines that congestion has occurred when packet loss is detected, and reduces the transmission rate. There are many methods for performing congestion control. This method is typified by CUBIC TCP (Non-Patent Document 1) and TCP NewReno (Non-Patent Document 2). As described above, in recent mobile communications, packet corruption due to bit errors is unlikely to occur. Therefore, in TCP using loss-based congestion control, the congestion window size (congestion window size, cwnd) continues to increase until the large-capacity buffer overflows and packet loss occurs. If a packet loss occurs after cwnd becomes enormous, the amount of packets that can be sent continuously after retransmission of the lost packet decreases, and there is a possibility that the sending of the packet may stop. When packet transmission is stopped due to packet loss, TCP throughput decreases, streaming content such as video and audio is interrupted, and the user experience quality is significantly impaired.

Measures for improvement as described in Patent Document 1 have been taken so far. Patent Document 1 is a technique in which a relay device is installed in the middle of a network, and TCP parameters are changed according to network types (wired network, wireless network, etc.) before and after the relay device. The TCP parameters exemplified in Patent Document 1 are the maximum value and minimum value of the retransmission timeout time (Retransmission Time Out, RTO), and the initial window size. It can be analogized that these are applied to other TCP parameters related to the amount of transmitted packets, such as the transmission buffer size. With this technology, by setting TCP parameters related to the amount of transmitted packets according to the network type, the amount of transmitted packets is limited in the LTE network, etc., and packet transmission suspension is reduced, and the quality of experience of the user is improved. Can do. Related techniques are disclosed in Patent Document 2, Patent Document 3, and Patent Document 4.

JP 2013-229834 A International Publication No. 2011/052079 JP 2013/191931 A JP 2008/78966 A

However, Patent Document 1 has a problem that the amount of transmitted packets cannot be flexibly limited because only the same parameter can be set in the same type of network. For example, when different network operators operate even with the same network type, the capacities of the buffers of the radio base station may be different. In addition, there is a possibility that network facilities having different buffer capacities are mixed in a transition period of facility expansion. Also, even if the buffer capacity is the same, the buffer may overflow early due to the influence of cross traffic or the like. Just setting parameters according to the network type as in Patent Document 1 cannot cope with the above-described case, and the packet transmission is still stopped, and the user's quality of experience is impaired.

Further, Patent Document 2 discloses a method for converting a numerical value related to communication speed limitation in a gateway device so that communication speeds between different networks are equalized. However, it cannot cope with restricting the congestion window size in accordance with the network state and appropriately controlling the amount of transmitted packets to suppress packet transmission suspension.

The present invention has been made in view of the above problems, and its purpose is to appropriately control the amount of transmitted packets in accordance with network conditions such as the transmission buffer capacity to suppress packet transmission suspension, It is to realize a network that improves the quality of experience.

The transmission data amount control device according to the present invention sets an upper limit value of the simultaneous transmission data amount based on information based on an acknowledgment packet, a data packet amount, and a simultaneous transmission data amount history in transmission / reception of a data packet using TCP. Transmission upper limit data amount calculating means, and transmission data amount limiting means for outputting a control signal for limiting the simultaneous transmission data amount based on the upper limit value.

The transmission data amount control system according to the present invention sets an upper limit value of the simultaneous transmission data amount based on information based on an acknowledgment packet, a data packet amount, and a simultaneous transmission data amount history in transmission / reception of a data packet using TCP. A transmission upper limit data amount calculating means, and a transmission data amount control means for outputting a control signal for limiting the simultaneous transmission data amount based on the upper limit value, and the control that is input A data transmission device that transmits an amount of the data packet based on a signal and supplies the data packet to the transmission data amount control device.

The transmission data amount control method according to the present invention sets the upper limit value of the simultaneous transmission data amount based on information based on the acknowledgment packet, the data packet amount, and the simultaneous transmission data amount history in transmission / reception of the data packet using TCP. Then, the simultaneous transmission data amount is limited based on the upper limit value.

The transmission data amount control program according to the present invention sets an upper limit value of the simultaneous transmission data amount based on information based on an acknowledgment packet, a data packet amount, and a simultaneous transmission data amount history in transmission / reception of a data packet using TCP. And a process of limiting the amount of simultaneous transmission data based on the upper limit value.

According to the present invention, it is possible to realize a network that improves the quality of user experience by appropriately controlling the amount of packets to be sent in accordance with the network conditions such as the capacity of the transmission buffer and suppressing the stop of packet sending.

It is a block diagram which shows the structure of the transmission data amount control apparatus of the 1st Embodiment of this invention. It is a block diagram which shows the structure of the transmission data amount control system of the 2nd Embodiment of this invention. It is a flowchart which shows operation | movement of the transmission data amount control system of the 2nd Embodiment of this invention. It is a block diagram which shows the structure of the transmission data amount control system of the 3rd Embodiment of this invention. It is a flowchart which shows operation | movement of the transmission data amount control system of the 3rd Embodiment of this invention. It is a block diagram which shows the structure of the transmission data amount control system of the 4th Embodiment of this invention. It is a flowchart which shows operation | movement of the transmission data amount control system of the 4th Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the preferred embodiments described below are technically preferable for carrying out the present invention, but the scope of the invention is not limited to the following.
(First embodiment)
FIG. 1 is a block diagram illustrating a configuration of a transmission data amount control apparatus according to the first embodiment of this invention. The transmission data amount control device 1 of the present embodiment uses the upper limit value of the simultaneous transmission data amount based on information based on an acknowledgment packet, a data packet amount, and a simultaneous transmission data amount history in transmission / reception of a data packet using TCP. The transmission upper limit data amount calculation means 2 is set. Further, the transmission data amount limiting means 3 outputs a control signal for limiting the simultaneous transmission data amount based on the upper limit value.

According to the present embodiment, it is possible to realize a network that appropriately controls the amount of packets to be sent in accordance with the network conditions such as the transmission buffer capacity, suppresses packet sending stop, and improves the quality of user experience. .
(Second Embodiment)
A second embodiment of the present invention will be described with reference to the drawings.
[Description of configuration]
FIG. 2 is a block diagram illustrating a configuration of a transmission data amount control system according to the second embodiment of this invention. The transmission data amount control system 4 of this embodiment includes a data transmission device 10a, a data reception device 20a, and a network 30a.

The data transmission device 10a can be an origin server that holds data requested by the user of the data reception device 20a. In addition, a relay server device such as a cache server, a proxy server, or an edge server that is installed in the network 30a and once terminates data communication between the origin server and the data receiving device 20a may be used. The data transmission device 10a establishes a connection such as TCP to the data reception device 20a, and transmits data requested from the data reception device 20a to the data reception device 20a.

The data receiving device 20a is a device that requests and acquires data from the data transmitting device 10a via the network 30a, such as a PC (Personal Computer) or a portable terminal.

The network 30a connects the data transmission device 10a and the data reception device 20a to perform data communication.

As described above, the data transmission device 10a may be arranged in the middle of the route as a relay server device when the origin server transmits data to the data reception device 20a. In that case, you may have an origin server, another network which connects an origin server, etc. in the back side of the data transmitter 10a seeing from the data receiver 20a.

The data transmission device 10a includes a data transmission / reception unit 11, a transmission rate control unit 12, a transmission upper limit data amount calculation unit 13, and a transmission data amount limitation unit 14. The data receiving device 20a has data transmitting / receiving means 21.

Based on the transmission rate determined by the transmission rate control unit 12, the data transmission / reception unit 11 transmits a data packet and ACK (ACKnowledgement,) to the data transmission / reception unit 21 of the data reception device 20a via the network 30a. (Acknowledgment) packet is received.

The transmission rate control means 12 controls the simultaneous transmission amount of the data packet based on the information of the ACK packet received by the data transmission / reception means 11 and the restriction on the simultaneous transmission data amount controlled by the transmission data amount restriction means 14.

The transmission upper limit data amount calculation means 13 performs simultaneous transmission based on the ACK packet information received by the data transmission / reception means 11, the amount of transmitted data packets, the history of the simultaneous transmission data amount determined by the transmission rate control means 12, and the like. Set the upper limit of data volume.

The transmission data amount limiting unit 14 limits the simultaneous transmission data amount determined by the transmission rate control unit 12 based on the upper limit value of the simultaneous transmission data amount determined by the transmission upper limit data amount calculation unit 13.

The data transmitting / receiving means 21 transmits a data request, receives a data packet, and transmits an ACK packet to the data transmitting device 10a via the network 30a.

When the data transmission / reception unit 11 acquires a data request message from the data transmission / reception unit 21 of the data reception device 20a, the data transmission / reception unit 11 transmits the requested data packet according to the simultaneous transmission data amount set by the transmission rate control unit 12. 21 to send. Here, when the data transmission device 10a is an origin server, the data transmission / reception means 11 can transmit data according to the set simultaneous transmission data amount because it holds all original data by itself.

When the data transmission device 10a is a relay server device, the original data is copied in advance as a cache in its own storage area, or the data stream transmitted from the origin server is temporarily stored as a buffer. Thereby, the data transmission / reception means 11 can transmit data according to the set simultaneous transmission data amount, without depending on the throughput of the network between the origin server and the data transmission device 10a.

Further, when receiving the ACK packet corresponding to the data packet from the data transmitting / receiving unit 21, the data transmitting / receiving unit 11 acquires the next information from the ACK packet. That is, a round trip delay (Round Trip Time, RTT), a reception window size (Receive Window size, RWIN) of communication between the data transmission device 10a and the data reception device 20a, and a duplicate ACK indicating the degree of congestion in communication. The message includes information such as exceeding the retransmission timeout period and an explicit congestion notification (ECN) message. The data transmitting / receiving unit 11 notifies the transmission rate control unit 12 of these pieces of information. The information acquisition and notification method can be the same as the known TCP method.

The transmission rate control means 12 controls the simultaneous transmission amount of data packets to be transmitted to the data receiving device 20a via the network 30a. This control is performed when the data transmission / reception unit 11 receives an ACK packet or at regular intervals, information obtained from the ACK packet received by the data transmission / reception unit 11 and the simultaneous transmission determined by the transmission data amount limiting unit 14 Based on data volume limitations. Here, the information obtained from the ACK packet is, for example, RTT, RWIN, duplicate ACK, excess of retransmission timeout, or ECN message. Further, the information is not limited to the above information, and may be other information that can be used by a known TCP.

Here, the control method of the simultaneous transmission amount of the data packet is obtained by adding the restriction on the simultaneous transmission data amount determined by the transmission data amount restriction means 14 to the known TCP control. The known TCP control includes congestion control for avoiding network congestion and flow control for avoiding memory overflow of the data receiving device 20a.

Congestion control increases or decreases cwnd managed by the data transmission device 10a. The increase / decrease method is, for example, CUBIC TCP (Non-Patent Document 1) or TCP NewReno (Non-Patent Document 2). The increase / decrease method is not limited to the increase / decrease method, and may be the same increase / decrease method as other known TCP congestion control methods. Further, the flow control limits the amount of simultaneous transmission of data packets so as not to exceed the RWIN notified from the data receiving device 20a. For limiting the amount of simultaneous transmission data, a parameter, which will be described later, determined by the transmission data amount limiting means 14 is read, and the simultaneous transmission amount of data packets is limited so as not to exceed this parameter. As a result, the transmission rate control means 12 can transmit an amount of data packets not exceeding any of cwnd, RWIN, and the parameters without waiting for the arrival of the ACK packet.

The transmission upper limit data amount calculation means 13 sets the upper limit value of the simultaneous transmission data amount. This setting is performed when the data transmission / reception unit 11 receives an ACK packet or at regular intervals, information on the ACK packet received by the data transmission / reception unit 11, the amount of transmitted data packets, and the transmission rate control unit 12. Is based on the history of the simultaneous transmission data amount determined by. Here, for setting the upper limit value, for example, cwnd when packet loss has been detected in the past or a statistical value of the history of the unACK data amount in_flight during communication through the network 30a may be set as the upper limit value. it can. The statistical value can be obtained by an exponential moving average of the history, a maximum value in a past fixed time, or a value obtained by removing an outlier by a known method. In order to suppress packet loss, a value obtained by subtracting several packets from the statistical value may be set as the upper limit value.

Further, the following method is not limited to the above setting method. That is, when the RTT measured or calculated by the data transmission / reception means 11 is monitored, and the average value of the RTT or the exponential moving average value increases by a predetermined threshold or more than the minimum value of the RTT, the RTT and the throughput at that time A value obtained by integrating the values may be set as the upper limit value. Further, a value obtained by adding a preset constant α of 0.5 or more and 1.0 or less to the value of RWIN described in the ACK packet received by the data transmitting / receiving unit 11 may be set as the upper limit value. Further, the time when the packet transmission from the data transmission / reception means 11 stops after the packet loss is monitored, and a variable β of 0.5 to 1.0 which becomes smaller as the stop time becomes longer is calculated, instead of the constant α. A value obtained by integrating the variable β with RWIN may be set as the upper limit value. Further, the maximum value or the minimum value among the values calculated by one or more setting methods may be set as the upper limit value.

The transmission data amount limiting unit 14 limits the simultaneous transmission data amount determined by the transmission rate control unit 12 based on the upper limit value when the transmission upper limit data amount calculation unit 13 sets the upper limit value of the simultaneous transmission data amount. give. Here, for example, a method of giving a limit is a method in which a maximum value is newly provided for cwnd that is increased or decreased by TCP congestion control, and an upper limit value is set to this maximum value. The method is not limited to the above method, and for example, an upper limit value may be set as an optional transmission buffer size of a communication socket, or a method of setting an upper limit value as a transmission memory size of a kernel variable of the data transmission device 10a. It may be.

The data receiving device 20a has data transmitting / receiving means 21 for transmitting a data request, receiving a data packet, and transmitting an ACK packet to the data transmitting device 10a via the network 30a. Then, when the data requested from the data transmission device 10a or the origin server is distributed, the data is presented to the user.

The data transmission / reception means 21 transmits a data request to the data transmission device 10a or the origin server via the network 30a when a data acquisition request is made by the user. Further, when a data packet is received from the data transmitting / receiving unit 11 of the data transmitting apparatus 10a, an ACK packet corresponding to the data packet is transmitted to the data transmitting / receiving unit 11. Here, the ACK packet can be the same as the ACK packet transmitted by a known TCP.
[Description of operation]
Next, the operation of the transmission data amount control system of this embodiment will be described in detail with reference to FIGS. FIG. 3 is a flowchart showing the operation of the transmission data amount control system 4 of the present embodiment.

(Step S11) When the data transmission / reception means 11 obtains a data request message from the data transmission / reception means 21, the data transmission / reception means 21 sends the requested data packet according to the simultaneous transmission data amount set by the transmission rate control means 12. Send to.

(Step S12) When the data transmitting / receiving unit 21 receives a data packet from the data transmitting / receiving unit 11, the data transmitting / receiving unit 21 transmits an ACK packet corresponding to the data packet to the data transmitting / receiving unit 11.

(Step S13) When the data transmission / reception means 11 receives the ACK packet from the data transmission / reception means 21, the information such as RTT, RWIN, duplicate ACK, excess of retransmission timeout, ECN message, etc. from the ACK packet Is sent to the transmission rate control means 12.

(Step S14) The transmission upper limit data amount calculation means 13 sets the upper limit value of the simultaneous transmission data amount when the data transmission / reception means 11 receives the ACK packet or at regular intervals. The transmission upper limit data amount calculation means 13 uses this upper limit value in the information of the ACK packet received by the data transmission / reception means 11, the amount of transmitted data packets, the history of the simultaneous transmission data amount determined by the transmission rate control means 12, and the like. Set based on.

(Step S15) The transmission data amount limiting unit 14 determines the simultaneous transmission determined by the transmission rate control unit 12 based on the upper limit value when the transmission upper limit data amount calculation unit 13 determines the upper limit value of the simultaneous transmission data amount. Limit the amount of data.

(Step S16) The transmission rate control means 12 controls the simultaneous transmission amount of data packets to be transmitted to the data receiving device 20a via the network 30a. The transmission rate control means 12 performs this control based on the information obtained from the ACK packet received by the data transmission / reception means 11 and the restriction on the simultaneous transmission data amount determined by the transmission data amount restriction means 14.

The transmission data amount control method of the present embodiment is a control method that performs the operation described in the configuration and operation of the transmission data amount control system 4 described above. Further, the transmission data amount control program of the present embodiment is a control program for executing the processing of the transmission data amount control method of the present embodiment.

As described above, according to the present embodiment, a network that appropriately controls the amount of transmitted packets and suppresses packet transmission suspension according to network conditions such as the transmission buffer capacity, and improves the quality of user experience. Can be realized.
(Third embodiment)
A third embodiment of the present invention will be described with reference to the drawings.
[Description of configuration]
FIG. 4 is a block diagram illustrating a configuration of a transmission data amount control system according to the third embodiment of this invention. The transmission data amount control system 5 of this embodiment includes a data transmission device 10b, a data reception device 20b, and a network 30b. The data transmission device 10 b includes a data transmission / reception unit 11 and a transmission rate control unit 12. The data receiving device 20b includes a data transmitting / receiving unit 21, a transmission upper limit data amount calculating unit 23, and a transmission data amount limiting unit 24.

The difference between this embodiment and the second embodiment is as follows. That is, in the transmission data amount control system 4 of the second embodiment, the data transmission device 10 a includes the transmission upper limit data amount calculation means 13 and the transmission data amount restriction means 14. On the other hand, in the transmission data amount control system 5 of the present embodiment, the data reception device 20b includes a transmission upper limit data amount calculation unit 23 and a transmission data amount limitation unit 24.

The transmission upper limit data amount calculation means 23 communicates in the RTT, cwnd controlled by the transmission rate control means 12, and the network 30b based on the amount of data packets received by the data transmission / reception means 21 and the reception time interval. The amount of unacknowledged data in_flight in the middle is estimated. Further, an upper limit value of the simultaneous transmission data amount is set based on the estimated value.

The transmission data amount restriction unit 24 restricts the simultaneous transmission data amount determined by the transmission rate control unit 12 of the data transmission device 10b based on the upper limit value of the simultaneous transmission data amount determined by the transmission upper limit data amount calculation unit 23. .

The transmission upper limit data amount calculation means 23 estimates the next value from the amount of data packets and the reception time interval when the data transmission / reception means 21 receives a data packet or at regular time intervals. That is, the RTT, cwnd controlled by the transmission rate control means 12, unacknowledged data amount in_flight during communication in the network 30b, and the like are estimated. Further, an upper limit value of the simultaneous transmission data amount is set based on the estimated value.

Here, for setting the upper limit value, for example, the statistical value of the estimated value of cwnd or in_flight when the duplicate ACK is transmitted to the data transmitting / receiving means 11 three times in the past can be set as the upper limit value. The statistical value can be obtained by either an exponential moving average of the estimated value, a maximum value in a past fixed time, or a value obtained by removing an outlier by a known method. In order to suppress packet loss, a value obtained by subtracting several packets from the statistical value may be set as the upper limit value.

Further, not limited to the setting method described above, when the average value of the estimated value of RTT or the exponential moving average value increases by a predetermined threshold or more than the minimum value of the estimated value of RTT, the estimated value of RTT at that time A value obtained by integrating the reception speed of data packets may be used as the upper limit value. Alternatively, a value obtained by integrating a preset constant γ of 1.0 or more to the estimated value of cwnd or in_flight may be used as the upper limit value. In addition, the maximum value or the minimum value among the values calculated by one or more setting methods may be used as the upper limit value.

When the transmission upper limit data amount calculation unit 23 sets the upper limit value of the simultaneous transmission data amount, the transmission data amount limitation unit 24 determines the simultaneous transmission rate control unit 12 of the data transmission device 10b based on the upper limit value. Limit the amount of transmitted data. The method of giving this restriction is, for example, a method in which a maximum value is further provided in RWIN that is increased or decreased by the OS (Operating System) of the data receiving apparatus 20b, and an upper limit value is set to this maximum value. The method is not limited to the above method. For example, an upper limit value may be set as an optional reception buffer size of a communication socket, or a method of setting an upper limit value as a reception memory size of a kernel variable of the data reception device 20b. It may be.

The transmission rate control means 12 acquires RWIN information via the data transmission / reception means 21 and the data transmission / reception means 11 of the data reception device 20b. Based on the information, the amount of simultaneous transmission of data packets is limited by flow control so as not to exceed RWIN, as in known TCP. As a result, the simultaneous transmission amount is limited to the upper limit value determined by the transmission upper limit data amount calculation means 23.
[Description of operation]
Next, the operation of the transmission data amount control system of this embodiment will be described in detail with reference to FIGS. FIG. 5 is a flowchart showing the operation of the transmission data amount control system 5 of the present embodiment.

(Step S21) The transmission upper limit data amount calculation means 23 estimates the next value from the amount of data packets and the reception time interval when the data transmission / reception means 21 receives a data packet or at regular intervals. . That is, RTT, cwnd controlled by the transmission rate control means 12, unacknowledged data amount in_flight during communication in the network 30b, and the like are estimated. Further, an upper limit value of the simultaneous transmission data amount is set based on the estimated value.

(Step S22) When the transmission upper limit data amount calculation unit 23 determines the upper limit value of the simultaneous transmission data amount, the transmission data amount limitation unit 24 determines the transmission rate control unit 12 of the data transmission device 10b based on the upper limit value. Limits the amount of data transmitted simultaneously.

(Step S23) The transmission rate control means 12 acquires RWIN information via the data transmission / reception means 21 and the data transmission / reception means 11 of the data reception device 20b. Based on the information, the amount of simultaneous transmission of data packets is limited by flow control so as not to exceed RWIN, as in known TCP.

The transmission data amount control method of the present embodiment is a control method that performs the operation described in the configuration and operation of the transmission data amount control system 5 described above. Further, the transmission data amount control program of the present embodiment is a control program for executing the processing of the transmission data amount control method of the present embodiment.

As described above, according to the present embodiment, a network that appropriately controls the amount of transmitted packets and suppresses packet transmission suspension according to network conditions such as the transmission buffer capacity, and improves the quality of user experience. Can be realized.
(Fourth embodiment)
A fourth embodiment of the present invention will be described with reference to the drawings.
[Description of configuration]
FIG. 6 is a block diagram illustrating a configuration of a transmission data amount control system according to the fourth embodiment of this invention. The transmission data amount control system 6 of this embodiment includes a data transmission device 10c, a data reception device 20c, and a network 30c. The data transmission device 10 c includes a data transmission / reception unit 11 and a transmission rate control unit 12. The data receiving device 20 c has data transmitting / receiving means 21.

The difference between this embodiment and the second embodiment is as follows. That is, in the transmission data amount control system 4 of the second embodiment, the data transmission device 10 a includes the transmission upper limit data amount calculation means 13 and the transmission data amount restriction means 14. On the other hand, in the transmission data amount control system 6 of the present embodiment, the network device 31 in the network 30c includes a transmission upper limit data amount calculation unit 33 and a transmission data amount limitation unit 34.

The transmission data amount control system 6 includes a network device 31 such as eNodeB, P-GW (Packet Data Network Gateway), S-GW (Serving Gateway), etc. in the network 30c.

The transmission upper limit data amount calculation means 33 communicates the RTT, the cwnd controlled by the transmission rate control means 12, and the network 30c based on the amount of data packets passed through the network device 31 and the passage time interval. The amount of unacknowledged data in_flight etc. is estimated. Further, an upper limit value of the simultaneous transmission data amount is set based on the estimated value.

The transmission data amount restriction unit 34 restricts the simultaneous transmission data amount determined by the transmission rate control unit 12 of the data transmission device 10c based on the upper limit value of the simultaneous transmission data amount determined by the transmission upper limit data amount calculation unit 33. .

The transmission upper limit data amount calculation means 33 estimates the next value from the amount of data packets that have passed and the time interval of passage when the data packets have passed through the network device 31 or at regular intervals. That is, the RTT, cwnd controlled by the transmission rate control unit 12, unacknowledged data amount in_flight during communication in the network 30c, and the like are estimated. Further, an upper limit value of the simultaneous transmission data amount is set based on the estimated value.

Here, in setting the upper limit value, for example, a statistical value of an estimated value of cwnd or in_flight when a packet loss occurs in the network device 31 can be set as the upper limit value. The statistical value is obtained by either an exponential moving average of estimated values, a maximum value in a past fixed time, or a value obtained by removing an outlier by a known method. In order to suppress packet loss, a value obtained by subtracting several packets from the statistical value may be set as the upper limit value.

Further, not limited to the above, when the average value of the estimated value of RTT or the exponential moving average value increases by a predetermined threshold or more than the minimum value of the estimated value of RTT, the estimated value of RTT at that time point, A value obtained by integrating the passing amount of data packets per unit time may be set as the upper limit value. Alternatively, a value obtained by integrating a preset constant α of 0.5 or more and 1.0 or less to the value of RWIN described in the ACK packet passing through the network device 31 may be used as the upper limit value. In addition, the time when the data packet passes through the network device 31 stops after the packet loss is monitored, and a variable β of 0.5 or more and 1.0 or less that decreases as the stop time becomes longer is calculated. Alternatively, a value obtained by integrating the variable β with RWIN may be used as the upper limit value. Further, the maximum value or the minimum value among the values calculated by one or more setting methods may be set as the upper limit value.

When the transmission upper limit data amount calculating unit 33 determines the upper limit value of the simultaneous transmission data amount, the transmission data amount limiting unit 34 is determined by the transmission rate control unit 12 of the data transmission device 10c based on the upper limit value. Limit the amount of transmitted data. The method of giving this restriction is, for example, the following method. That is, when the estimated value of in_flight of each communication session or the entire communication session or the queue amount accumulated in the network device 31 exceeds the upper limit value, a flag is added to the header of the data packet that has passed through the network device 31. . This flag is a CE (Congestion Experienced) flag of the ECN option. In addition to the above method, for example, a method of randomly discarding a data packet that has passed through the network device 31 when the upper limit value is exceeded as described above may be used.

The transmission rate control means 12 acquires ECN messages or duplicate ACK information caused by packet loss via the data transmission / reception means 21 and the data transmission / reception means 11 of the data reception device 20c. Based on the information, cwnd is controlled by congestion control in the same manner as known TCP. As a result, the simultaneous transmission amount of data packets is indirectly limited to the upper limit value determined by the transmission upper limit data amount calculation means 33.
[Description of operation]
Next, the operation of the transmission data amount control system of this embodiment will be described in detail with reference to FIGS. FIG. 7 is a flowchart showing the operation of the transmission data amount control system 6 of this embodiment.

(Step S31) The transmission upper limit data amount calculation means 33 calculates the following value from the amount of data packets that have passed and the time interval of passage when the data packets have passed through the network device 31 or at regular intervals. presume. That is, the RTT, cwnd controlled by the transmission rate control unit 12, unacknowledged data amount in_flight during communication in the network 30c, and the like are estimated. Further, an upper limit value of the simultaneous transmission data amount is set based on the estimated value.

(Step S32) When the transmission upper limit data amount calculation unit 33 determines the upper limit value of the simultaneous transmission data amount, the transmission data amount limitation unit 34 determines the transmission rate control unit 12 of the data transmission device 10c based on the upper limit value. Limits the amount of data transmitted simultaneously.

(Step S33) The transmission rate control means 12 acquires ECN messages or duplicate ACK information caused by packet loss via the data transmission / reception means 21 and the data transmission / reception means 11 of the data reception device 20c. Based on the information, cwnd is controlled by congestion control in the same manner as known TCP.

The transmission data amount control method of the present embodiment is a control method that performs the operation described in the configuration and operation of the transmission data amount control system 6 described above. Further, the transmission data amount control program of the present embodiment is a control program for executing the processing of the transmission data amount control method of the present embodiment.

As described above, according to the present embodiment, a network that appropriately controls the amount of transmitted packets and suppresses packet transmission suspension according to network conditions such as the transmission buffer capacity, and improves the quality of user experience. Can be realized.

The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the invention described in the claims, and these are also included in the scope of the present invention.

In addition, a part or all of the above embodiment can be described as in the following supplementary notes, but is not limited to the following.

Appendix (Appendix 1)
Transmission upper limit data amount calculating means for setting an upper limit value of the simultaneous transmission data amount based on information based on an acknowledgment packet, a data packet amount, and a simultaneous transmission data amount history in transmission / reception of a data packet using TCP,
A transmission data amount control device, comprising: a transmission data amount limiting means for outputting a control signal for limiting the simultaneous transmission data amount based on the upper limit value.
(Appendix 2)
The transmission upper limit data amount calculation means and the transmission data amount restriction means are provided in a data transmission apparatus when performing the transmission / reception,
The transmission upper limit data amount calculating means includes:
Based on the congestion window size when packet loss is detected, or
Based on statistics of unacknowledged data volume, or
When the measured or calculated average value of the delay time or exponential moving average value is increased by a predetermined threshold or more than the minimum value of the delay time, based on the value obtained by integrating the delay time and the throughput at that time Or
Based on the reception window size described in the acknowledgment packet received by the data transmission device and the time when transmission of the data packet from the data transmission device stops after detection of the packet loss,
The transmission data amount control device according to attachment 1, wherein the upper limit value is set.
(Appendix 3)
The transmission data amount limiting means is based on the upper limit value,
By setting a maximum value to the congestion window size and changing the maximum value, or
By changing the transmission buffer size of the socket option or the transmission memory size of the kernel variable of the data transmission device,
The transmission data amount control device according to appendix 2, which limits the amount of simultaneous transmission data.
(Appendix 4)
The transmission upper limit data amount calculation means and the transmission data amount restriction means are provided in a data receiving apparatus when performing the transmission / reception,
The transmission upper limit data amount calculating means includes:
Based on the statistical value of the estimated value of the congestion window size when detecting packet loss or the amount of unacknowledged data, or
When the estimated average value of the delay time or exponential moving average value is increased by a predetermined threshold or more than the minimum value of the delay time, the delay time at that time and the data packet in the data receiving device Based on the sum of the received amount per unit time,
The transmission data amount control device according to attachment 1, wherein the upper limit value is set.
(Appendix 5)
The transmission data amount limiting means is based on the upper limit value,
By setting a maximum value for the reception window size, changing the maximum value, or
By changing the reception buffer size of the socket option or the reception memory size of the kernel variable of the data reception device,
The transmission data amount control device according to appendix 4, which limits the amount of simultaneous transmission data.
(Appendix 6)
The transmission upper limit data amount calculation means and the transmission data amount restriction means are provided in a network device included in the network that performs the transmission and reception,
The transmission upper limit data amount calculating means includes:
Based on the statistical value of the estimated value of the congestion window size when the network device discards the data packet or the amount of unacknowledged data, or
When the estimated average value of the delay time or exponential moving average value is increased by a predetermined threshold or more than the minimum value of the delay time, the delay time at that time and the unit time of the data packet in the network device Based on the integrated value of the passage amount of
Based on the reception window size described in the acknowledgment packet passing through the network device, and the time when the network device stops passing the data packet after the network device discards the data packet,
The transmission data amount control device according to attachment 1, wherein the upper limit value is set.
(Appendix 7)
The transmission data amount limiting means is based on the upper limit value,
By changing the queue amount to which the congestion detection flag of explicit congestion notification is added, or
By randomly discarding data packets that pass through the network device when the upper limit is exceeded,
The transmission data amount control device according to appendix 6, which limits the simultaneous transmission data amount.
(Appendix 8)
The transmission data amount control device according to any one of appendix 1 to appendix 7,
A transmission data amount control system comprising: a data transmission device that transmits the amount of the data packet based on the input control signal and supplies the data packet to the transmission data amount control device.
(Appendix 9)
The transmission upper limit data amount control device is provided in the data transmission device,
The transmission upper limit data amount calculating means includes:
Based on the congestion window size when packet loss is detected, or
Based on statistics of unacknowledged data volume, or
When the measured or calculated average value of the delay time or exponential moving average value is increased by a predetermined threshold or more than the minimum value of the delay time, based on the value obtained by integrating the delay time and the throughput at that time Or
Based on the reception window size described in the acknowledgment packet received by the data transmission device and the time when transmission of the data packet from the data transmission device stops after detection of the packet loss,
The transmission data amount control system according to appendix 8, wherein the upper limit value is set.
(Appendix 10)
The transmission data amount limiting means is based on the upper limit value,
By setting a maximum value to the congestion window size and changing the maximum value, or
By changing the transmission buffer size of the socket option or the transmission memory size of the kernel variable of the data transmission device,
The transmission data amount control system according to appendix 9, wherein the simultaneous transmission data amount is limited.
(Appendix 11)
The transmission upper limit data amount control device is provided in a data receiving device when performing the transmission / reception,
The transmission upper limit data amount calculating means includes:
Based on the statistical value of the estimated value of the congestion window size when detecting packet loss or the amount of unacknowledged data, or
When the estimated average value of the delay time or exponential moving average value is increased by a predetermined threshold or more than the minimum value of the delay time, the delay time at that time and the data packet in the data receiving device Based on the sum of the received amount per unit time,
The transmission data amount control system according to appendix 8, wherein the upper limit value is set.
(Appendix 12)
The transmission data amount limiting means is based on the upper limit value,
By setting a maximum value for the reception window size, changing the maximum value, or
By changing the reception buffer size of the socket option or the reception memory size of the kernel variable of the data reception device,
The transmission data amount control system according to appendix 11, which limits the amount of simultaneous transmission data.
(Appendix 13)
The transmission upper limit data amount control device is provided in a network device having a network that performs the transmission and reception,
The transmission upper limit data amount calculating means includes:
Based on the statistical value of the estimated value of the congestion window size when the network device discards the data packet or the amount of unacknowledged data, or
When the estimated average value of the delay time or exponential moving average value is increased by a predetermined threshold or more than the minimum value of the delay time, the delay time at that time and the unit time of the data packet in the network device Based on the integrated value of the passage amount of
Based on the reception window size described in the acknowledgment packet passing through the network device, and the time when the network device stops passing the data packet after the network device discards the data packet,
The transmission data amount control system according to appendix 8, wherein the upper limit value is set.
(Appendix 14)
The transmission data amount limiting means is based on the upper limit value,
By changing the queue amount to which the congestion detection flag of explicit congestion notification is added, or
By randomly discarding data packets that pass through the network device when the upper limit is exceeded,
14. The transmission data amount control system according to appendix 13, wherein the simultaneous transmission data amount is limited.
(Appendix 15)
In the transmission and reception of data packets using TCP, based on the information based on the acknowledgment packet, the data packet amount and the simultaneous transmission data amount history, the upper limit value of the simultaneous transmission data amount is set,
A transmission data amount control method for limiting the amount of simultaneous transmission data based on the upper limit value.
(Appendix 16)
Based on the congestion window size when packet loss is detected, or
Based on statistics of unacknowledged data volume, or
When the measured or calculated average value of the delay time or exponential moving average value is increased by a predetermined threshold or more than the minimum value of the delay time, based on the value obtained by integrating the delay time and the throughput at that time Or
Based on the reception window size described in the acknowledgment packet received by the data transmission device when performing the transmission and reception, and the time when transmission of the data packet from the data transmission device stops after detection of the packet loss,
The transmission data amount control method according to appendix 15, wherein the upper limit value is set.
(Appendix 17)
Based on the upper limit,
By setting a maximum value to the congestion window size and changing the maximum value, or
By changing the transmission buffer size of the socket option or the transmission memory size of the kernel variable of the data transmission device,
The transmission data amount control method according to appendix 16, wherein the simultaneous transmission data amount is limited.
(Appendix 18)
Based on the statistical value of the estimated value of the congestion window size when detecting packet loss or the amount of unacknowledged data, or
When the estimated average value of the delay time or exponential moving average value is increased by a predetermined threshold or more than the minimum value of the delay time, the delay time at that time and the data reception at the time of transmission / reception Based on the sum of the received amount of data packets per unit time in the device,
The transmission data amount control method according to appendix 15, wherein the upper limit value is set.
(Appendix 19)
Based on the upper limit,
By setting a maximum value for the reception window size, changing the maximum value, or
By changing the reception buffer size of the socket option or the reception memory size of the kernel variable of the data reception device,
The transmission data amount control method according to appendix 18, wherein the simultaneous transmission data amount is limited.
(Appendix 20)
Based on the statistical value of the estimated value of the congestion window size when the network device of the network performing the transmission / reception discards the data packet, or the amount of unacknowledged data, or
When the estimated average value of the delay time or exponential moving average value is increased by a predetermined threshold or more than the minimum value of the delay time, the delay time at that time and the unit time of the data packet in the network device Based on the integrated value of the passage amount of
Based on the reception window size described in the acknowledgment packet passing through the network device, and the time when the network device stops passing the data packet after the network device discards the data packet,
The transmission data amount control method according to appendix 15, wherein the upper limit value is set.
(Appendix 21)
Based on the upper limit,
By changing the queue amount to which the congestion detection flag of explicit congestion notification is added, or
By randomly discarding data packets that pass through the network device when the upper limit is exceeded,
The transmission data amount control method according to appendix 20, wherein the simultaneous transmission data amount is limited.
(Appendix 22)
In the transmission and reception of data packets using TCP, a process of setting the upper limit value of the simultaneous transmission data amount based on information based on an acknowledgment packet, a data packet amount, and a simultaneous transmission data amount history;
A transmission data amount control program that executes processing for limiting the amount of simultaneous transmission data based on the upper limit value.
(Appendix 23)
Based on the congestion window size when packet loss is detected, or
Based on statistics of unacknowledged data volume, or
When the measured or calculated average value of the delay time or exponential moving average value is increased by a predetermined threshold or more than the minimum value of the delay time, based on the value obtained by integrating the delay time and the throughput at that time Or
Based on the reception window size described in the acknowledgment packet received by the data transmission device when performing the transmission and reception, and the time when transmission of the data packet from the data transmission device stops after detection of the packet loss,
The transmission data amount control program according to appendix 22, wherein the program for executing the process of setting the upper limit value is executed.
(Appendix 24)
Based on the upper limit,
By setting a maximum value to the congestion window size and changing the maximum value, or
By changing the transmission buffer size of the socket option or the transmission memory size of the kernel variable of the data transmission device,
24. The transmission data amount control program according to appendix 23, which executes processing for limiting the simultaneous transmission data amount.
(Appendix 25)
Based on the statistical value of the estimated value of the congestion window size when detecting packet loss or the amount of unacknowledged data, or
When the estimated average value of the delay time or exponential moving average value is increased by a predetermined threshold or more than the minimum value of the delay time, the delay time at that time and the data reception at the time of transmission / reception Based on the sum of the received amount of data packets per unit time in the device,
The transmission data amount control program according to appendix 22, wherein the program for executing the process of setting the upper limit value is executed.
(Appendix 26)
Based on the upper limit,
By setting a maximum value for the reception window size, changing the maximum value, or
By changing the reception buffer size of the socket option or the reception memory size of the kernel variable of the data reception device,
26. The transmission data amount control program according to appendix 25, which executes processing for limiting the simultaneous transmission data amount.
(Appendix 27)
Based on the statistical value of the estimated value of the congestion window size when the network device of the network performing the transmission / reception discards the data packet, or the amount of unacknowledged data, or
When the estimated average value of the delay time or exponential moving average value is increased by a predetermined threshold or more than the minimum value of the delay time, the delay time at that time and the unit time of the data packet in the network device Based on the integrated value of the passage amount of
Based on the reception window size described in the acknowledgment packet passing through the network device, and the time when the network device stops passing the data packet after the network device discards the data packet,
24. A transmission data amount control program according to appendix 22, wherein the upper limit value is set.
(Appendix 28)
Based on the upper limit,
By changing the queue amount to which the congestion detection flag of explicit congestion notification is added, or
By randomly discarding data packets that pass through the network device when the upper limit is exceeded,
28. The transmission data amount control program according to appendix 27, which executes processing for limiting the simultaneous transmission data amount.

This application claims priority based on Japanese Patent Application No. 2014-117175 filed on June 6, 2014, the entire disclosure of which is incorporated herein.

The present invention can be used for a communication technique for transmitting and receiving data packets using TCP.

DESCRIPTION OF SYMBOLS 1 Transmission data amount control apparatus 2, 13, 23, 33 Transmission upper limit data amount calculation means 3, 14, 24, 34 Transmission data amount restriction means 4, 5, 6 Transmission data amount control system 10, 10a, 10b, 10c Data transmission Device 20, 20a, 20b, 20c Data receiving device 30, 30a, 30b, 30c Network 11, 21 Data transmission / reception means 12 Transmission rate control means 31 Network equipment

Claims (10)

1. Transmission upper limit data amount calculating means for setting an upper limit value of the simultaneous transmission data amount based on information based on an acknowledgment packet, a data packet amount, and a simultaneous transmission data amount history in transmission / reception of a data packet using TCP,
   A transmission data amount control device, comprising: a transmission data amount limiting means for outputting a control signal for limiting the simultaneous transmission data amount based on the upper limit value.
2. The transmission upper limit data amount calculation means and the transmission data amount restriction means are provided in a data transmission apparatus when performing the transmission / reception,
   The transmission upper limit data amount calculating means includes:
   Based on the congestion window size when packet loss is detected, or
   Based on statistics of unacknowledged data volume, or
   When the measured or calculated average value of the delay time or exponential moving average value is increased by a predetermined threshold or more than the minimum value of the delay time, based on the value obtained by integrating the delay time and the throughput at that time Or
   Based on the reception window size described in the acknowledgment packet received by the data transmission device and the time when transmission of the data packet from the data transmission device stops after detection of the packet loss,
   The transmission data amount control device according to claim 1, wherein the upper limit value is set.
3. The transmission data amount limiting means is based on the upper limit value,
   By setting a maximum value to the congestion window size and changing the maximum value, or
   By changing the transmission buffer size of the socket option or the transmission memory size of the kernel variable of the data transmission device,
   The transmission data amount control device according to claim 2, wherein the simultaneous transmission data amount is limited.
4. The transmission upper limit data amount calculation means and the transmission data amount restriction means are provided in a data receiving apparatus when performing the transmission / reception,
   The transmission upper limit data amount calculating means includes:
   Based on the statistical value of the estimated value of the congestion window size when detecting packet loss or the amount of unacknowledged data, or
   When the estimated average value of the delay time or exponential moving average value is increased by a predetermined threshold or more than the minimum value of the delay time, the delay time at that time and the data packet in the data receiving device Based on the sum of the received amount per unit time,
   The transmission data amount control device according to claim 1, wherein the upper limit value is set.
5. The transmission data amount limiting means is based on the upper limit value,
   By setting a maximum value for the reception window size, changing the maximum value, or
   By changing the reception buffer size of the socket option or the reception memory size of the kernel variable of the data reception device,
   The transmission data amount control device according to claim 4, wherein the simultaneous transmission data amount is limited.
6. The transmission upper limit data amount calculation means and the transmission data amount restriction means are provided in a network device included in the network that performs the transmission and reception,
   The transmission upper limit data amount calculating means includes:
   Based on the statistical value of the estimated value of the congestion window size when the network device discards the data packet or the amount of unacknowledged data, or
   When the estimated average value of the delay time or exponential moving average value is increased by a predetermined threshold or more than the minimum value of the delay time, the delay time at that time and the unit time of the data packet in the network device Based on the integrated value of the passage amount of
   Based on the reception window size described in the acknowledgment packet passing through the network device, and the time when the network device stops passing the data packet after the network device discards the data packet,
   The transmission data amount control device according to claim 1, wherein the upper limit value is set.
7. The transmission data amount limiting means is based on the upper limit value,
   By changing the queue amount to which the congestion detection flag of explicit congestion notification is added, or
   By randomly discarding data packets that pass through the network device when the upper limit is exceeded,
   The transmission data amount control device according to claim 6, wherein the simultaneous transmission data amount is limited.
8. A transmission data amount control device according to any one of claims 1 to 7,
   A transmission data amount control system comprising: a data transmission device that transmits the amount of the data packet based on the input control signal and supplies the data packet to the transmission data amount control device.
9. In the transmission and reception of data packets using TCP, based on the information based on the acknowledgment packet, the data packet amount and the simultaneous transmission data amount history, the upper limit value of the simultaneous transmission data amount is set,
   A transmission data amount control method for limiting the amount of simultaneous transmission data based on the upper limit value.
10. In the transmission and reception of data packets using TCP, a process of setting the upper limit value of the simultaneous transmission data amount based on information based on an acknowledgment packet, a data packet amount, and a simultaneous transmission data amount history;
    A storage medium storing a transmission data amount control program for executing processing for limiting the amount of simultaneous transmission data based on the upper limit value.

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