JP2002217966A - Method and device for dynamically controlling bandwidth in ip network - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology for controlling the bandwidth which reduces fluctuation in UDP data transmission, for assured effective band. SOLUTION: The technology for controlling bandwidth is provided for a communication system environment, in which a device for transmitting data with TCP and UDP is connected via an IP network 101. The device monitors a UDP data transmission amount, while changes the window size of TCP as the UDP data transmission amount increases, so that a bandwidth used for TCP data transmission is controlled, to reduce fluctuations in UDP data transmission.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a dynamic bandwidth control technique for controlling TCP / IP traffic according to a communication system environment connected to an IP network.
A dynamic bandwidth control method on an IP network capable of reducing fluctuations in UDP data transmission when data transmission by TCP and UDP is performed in parallel between devices connected on the IP network, and using the method. The present invention relates to a dynamic bandwidth control device.

[0002]

2. Description of the Related Art IP (Internet Protocol)
ol) network, the transport layer protocol of the OSI reference model is TCP (Transfer Content).
rolProtocol) and UDP (User Dat)
(Agr. Protocol) is used. TCP
Is a so-called connection-type communication connection that requires mutual confirmation of TCP connections before data exchange. It has functions such as packet order control, flow control, error detection and recovery, retransmission, and congestion control. And provide reliable communication services.

[0003] The reliable communication services provided by TCP can be contrasted with the unreliable datagram protocol UDP which is also provided on IP networks.

[0004] UDP is a connectionless protocol, and is used for communication that requires real-time performance because it does not have a function like TCP. For example, in order to realize a voice call, it is not important to retransmit even if some data is lost, and the current voice data generated must be transmitted one after another. UDP is used for such communication as voice that requires real-time properties. U
DP is used when a transmission error occurs, when network hardware fails, or when the network is overloaded and cannot handle the assigned load.
Packet loss or destruction may occur. on the other hand,
TCP specifies an acknowledgment that two computers will alternately achieve a reliable transfer, as well as a procedure to ensure that data arrives correctly.

[0005] In the communication on the IP network, if data that occurs discretely is transmitted during transmission of data that continuously occurs, such as voice, continuous data transmission that requires real-time performance is required. Fluctuations (missing data)
If no control is performed, the quality of data transmission that requires real-time performance will be significantly reduced.
Therefore, T between devices connected on the IP network.
When data transmission by CP and UDP is performed in parallel, it is desirable to perform bandwidth control to improve the bandwidth utilization efficiency of the network in order to guarantee the quality of communication services requiring real-time between devices. .

In general, a path control device such as a router (hereinafter referred to as a “router device”) is used to realize communication between networks. This router device is widely used particularly in information data communication via the Internet, and plays an important role in configuring the Internet. The role of the router device is to select a valid route for an input communication packet, perform routing processing (determination of a destination), and output the result, and do not have a control function for securing a bandwidth between networks. . However, in a special router device,
By assigning a value indicating whether the priority is high or low for each packet, and prioritizing and processing data that requires high-priority real-time performance, priority is given to the bandwidth used in data transmission requiring real-time performance. Enables bandwidth control to be secured. Therefore, by using the above-described router device, effective priority control and band control can be achieved for a wide range of data from high real-time data to bulk data regardless of real-time performance.

[0007]

In the conventional bandwidth control method, a special router device having a priority control function based on bandwidth reservation must be incorporated in the communication network configuration. Not suitable for In addition, since the processing load of priority control based on bandwidth reservation is large in the router device, there is a problem that network resources may be reduced.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned disadvantages of the prior art, and to use a special router when executing data transmission by TCP and UDP in parallel between devices connected on an IP network. Instead, it is an object of the present invention to provide a bandwidth control method on an IP network that realizes effective bandwidth securing by reducing fluctuations caused by data transmission by UDP by software implementation.

[0009]

According to a first aspect of the present invention, there is provided a dynamic bandwidth control method comprising:
Monitoring the UDP data transmission amount between devices capable of executing data transmission by TCP and UDP in parallel on the network;
Changing the TCP window size to control the bandwidth used for the TCP data transmission.

In a second aspect, the dynamic bandwidth control method comprises:
TCP and UD between devices connected on the IP network
UDP if data transmission by P is performed in parallel
Monitoring the data transmission amount, and controlling the network bandwidth by dynamically changing the TCP window size as the UDP data transmission amount increases or decreases. Fluctuations that occur in data transmission by UDP are reduced, and effective band securing is realized. In the second invention, the step of monitoring the UDP data transmission amount includes measuring a UDP data reception amount within a certain period of time, and determining whether the measured value is equal to or greater than a predetermined threshold value or less than a threshold value. Decrease or increase the amount of UDP data transmission. Also, the step of dynamically changing the TCP window size includes, beforehand, retaining each window size setting value corresponding to the increase / decrease of the UDP data transmission amount, and determining the increase / decrease of the UDP data transmission amount. Accordingly, the window size setting value corresponding to the increase or decrease of the UDP data transmission amount is selected, and the current window size of the TCP is changed to the selected window size setting value.

In a third aspect, the dynamic bandwidth control device comprises:
A monitoring unit that monitors the amount of UDP data transmission between devices that can execute TCP and UDP data transmission in parallel on an IP network, and changes the window size of the TCP as the amount of UDP data transmission changes Then the TCP
A bandwidth control unit that controls a bandwidth used for data transmission.

In the fourth invention, the dynamic bandwidth control is performed based on the IP
When data transmission by TCP and UDP is performed in parallel between devices connected on the network, a monitoring unit that monitors the amount of UDP data transmission, and a change in the amount of UDP data, A bandwidth control unit that controls a network bandwidth by dynamically changing a window size to reduce fluctuations generated in data transmission by the UDP between the devices and realize effective bandwidth securing. .
In the fourth invention, the monitoring unit that monitors the amount of UDP data transmission measures the amount of received UDP data within a certain period of time, and determines whether the measured value is equal to or greater than a predetermined threshold or less than the threshold. The increase / decrease of the UDP data transmission amount is determined. Further, the bandwidth control unit that dynamically changes the window size of the TCP previously holds the respective window size setting values corresponding to the increase / decrease of the UDP data transmission amount, and controls the UDP data transmission amount. As the increase or decrease is determined, a window size setting value corresponding to the increase or decrease of the UDP data transmission amount is selected, and the current window size of the TCP is set.
Change the size to the selected window size setting.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a dynamic bandwidth control method in an IP network according to the present invention will be described with reference to the drawings by using some embodiments. FIG. 1 is a diagram showing a configuration example of a communication system to which a bandwidth control method according to the present invention is applied. The communication system shown in the figure is a LAN (Local A)
C connected by a network (rear network) 104
TI (Computer TelephonyInte
(gration) server 103 and operator terminal 10
2 and the Web server 105 are connected via IP (Inter
This is an example of a communication system that connects to a customer computer 100 via a network (net protocol) network 101.

In this communication system, a customer computer 100 and an operator terminal 102 are connected via an IP network 101 and perform voice communication by UDP. At the same time, the Web server 105 is connected to the customer computer 100 and the operator terminal 102, and the customer computer 100 and the operator terminal 102
B page can be browsed. As described above, the voice communication between the customer computer 100 and the operator terminal 102 is performed, and at the same time, the customer computer 100 and the operator terminal 102 can browse the same Web page.

FIG. 2 is a diagram showing an embodiment of the software configuration of the customer computer shown in FIG. In the customer computer 100 shown in the figure, the UDP data transmission amount monitoring unit 201
Operator terminal 102 connected via network 101
The transmission amount of the UDP packet received from the communication device is measured within a certain period of time, and the start / end of voice communication is recognized based on the increase / decrease of the UDP data transmission amount. This measurement of the amount of UDP data transmission is performed continuously, and when the measured value is equal to or greater than a preset threshold value, and conversely, when the measured value is less than the threshold value, the state of voice communication is determined. Make a decision. For example,
If the measured value is equal to or greater than a preset threshold value, it is determined that the voice transmission has been started, and if the measured value is less than the threshold value, it is determined that the voice transmission has decreased or has ended. judge. Further, when the voice communication state is determined, a function of transmitting a request signal for bandwidth control of TPC to the communication bandwidth control unit 202 of the customer computer 100 is provided.

The bandwidth control method according to the present invention gives priority to securing the bandwidth of data requiring real-time performance by UDP,
In order to reduce the fluctuation that occurs in UDP data transmission,
TCP during UDP data transmission causing fluctuation
This is TCP bandwidth control by limiting the amount of data transmission. That is, the fluctuation of the UDP data transmission is reduced by limiting the bandwidth used for the TCP data transmission by a fixed value at the time of the UDP data transmission, instead of performing the optimal bandwidth control for the TCP data transmission. Things.

FIG. 3 is a diagram showing a configuration of a TCP header used in data transmission by TCP. Bandwidth control in TCP data transmission generally uses TC
A bandwidth control mechanism based on the window size in the WINDOW field of the P header has been defined.

Next, the operation of the bandwidth control processing in the communication system according to the present embodiment will be described in detail with reference to FIGS. FIG. 4 is a sequence diagram showing one embodiment of the band control process in the customer computer. In the communication system according to the present embodiment, when voice communication by UDP is started from the operator terminal 102 to the customer computer 100, in step 401, the customer computer 1
00 is the UDP data transmission amount monitoring unit 201
Recognize the start of voice communication as the data transmission volume increases. In step 402, a "bandwidth control start request" is notified to the communication bandwidth control unit 202 of the customer computer 100.

Next, in step 403, the communication bandwidth control unit 202 selects a window size setting value to be changed upon receiving the “bandwidth control start request” in step S402. The window size setting value is a value corresponding to the maximum length of a TCP1 packet adapted at the start of voice communication, and a value corresponding to a TCPN packet length adapted at the end of voice communication (N> 1, where N is arbitrary ) Are provided in advance. In step 404, a TCP connection from the Web server 105 for a TCP connection to be established thereafter is requested. In this request,
For example, SYNwin 8192 <miss1460
Send> Here, SYN indicates the start of the TCP connection, win indicates the window size, and <mi
ss1460> indicates the size of one unit of data. Step 406 determines whether the window size transmitted in step 404 is larger or smaller than the window size set in step 403. Web server 1
If the window size sent from the server 05 is small, the window size is used and the Web server 10
If the window size sent from the client computer 100 is large, then at step 406 the T
The window size in the CP header is determined in step 403.
Change to the window size setting value selected in
b. Reply to server 105. In the system according to the present embodiment, the time period 408 during the UDP data transmission is set by using the window size selected according to the UDP data transmission amount for the TCP connection request 407 discretely generated after the step 403. The fluctuation of the UDP data transmission is reduced by suppressing the TCP data transmission amount and securing the band in the UDP data transmission.

FIG. 5 is a sequence diagram showing another embodiment of the band control processing in the customer computer. Further, in the present system, when the voice communication is terminated at the operator terminal 102, at step 501, the customer computer 10
In step 50, the UDP data transmission amount monitoring unit 201 recognizes the end of the voice call as the UDP data transmission amount decreases.
In step 2, the “bandwidth control stop request” is sent to the customer computer 1
00 to the communication bandwidth control unit 202.

Next, upon receiving the “bandwidth control stop request” at step 502, the communication bandwidth control unit 202 determines at step 503 that the window / window to be changed
Select the size setting value. In step 504,
If the Web server 105 issues a TCP connection request to the client computer 100 to establish the connection thereafter, in step 505, the Web server 10
Window with window size set from 5
It is determined whether the size is larger than the size, and in step 506, the window size in the TCP header of the customer computer 100 is changed to the window size setting value selected in step S503. Therefore, step 50
As shown in a time zone 507, for a TCP connection that discretely occurs after the third time, when the UDP data is not transmitted, the restriction on the TCP data transmission use band is released, and the optimum bandwidth in the TCP data transmission is released. Can be secured. As described above, in the present embodiment, by using the window size selected according to the transmission amount, the TCP data transmission amount suppression for securing the band in the UDP data transmission is eliminated, and the effective use band in the TCP data transmission is eliminated. Width can be provided.

As described above, in the bandwidth control method according to the present embodiment, when data transmission by TCP and UDP is performed in parallel between devices connected on the IP network,
It monitors the increase and decrease of the data transmission amount, and changes the TCP window size according to the increase and decrease of the UDP data transmission amount.
By controlling the bandwidth used by the CP data transmission, fluctuations in the UDP data transmission can be reduced, and an effective bandwidth used in the data transmission by the TCP and the UDP can be provided.

The above-described band control method and apparatus according to the present invention have the following features. The first feature is
The device that performs data transmission using TCP and UDP is IP
A communication system environment connected via a network,
The apparatus comprises means for monitoring the amount of transmitted and received UDP data, and means for changing the TCP window size according to the increase or decrease in the amount of transmitted UDP data. The second feature is that the means for monitoring the UDP data transmission amount repeats the process of measuring the UDP data transmission amount received within a certain period of time, and increases or decreases the data transmission amount based on a preset threshold value. Is determined. A third feature is that the means for changing the TCP window size in accordance with the increase in the amount of UDP data transmission holds in advance each window size setting value corresponding to the increase or decrease in the amount of UDP data transmission. After selecting the window size setting value corresponding to the increase or decrease of the UDP data transmission amount, the current window size of TCP is changed to the selected window size setting value.

As described above, according to the present invention, since it can be provided by software implementation, bandwidth control can be realized without using a special router device having a priority control function based on bandwidth reservation. . Therefore, application to a general-purpose communication network configuration is easily possible. Further, it is possible to eliminate a cause of a decrease in bandwidth utilization efficiency, such as a decrease in network resources due to an increase in a processing load of priority control based on bandwidth reservation in the router device.

Further, according to the present invention, when data transmission by TCP and UDP is performed in parallel between devices connected on the IP network, the increase or decrease of the UDP data transmission amount is determined by monitoring the UDP data transmission amount. In addition, in order to control the bandwidth used in the TCP data transmission according to the increase or decrease of the UDP data transmission amount, when the UDP data transmission amount is increased, the TCP data is transmitted between the devices during the continuous data transmission by the UDP. U generated when transmission interrupts
It is possible to reduce the fluctuation of DP data transmission,
It is possible to realize the quality assurance of communication services that require real-time properties, and when the amount of UDP data transmission is reduced, perform control to eliminate the limitation on the bandwidth used for data transmission by TCP, thereby realizing network Of the band can be improved.

[0026]

As described above, according to the present invention, T
When data transmission by CP and UDP is performed in parallel, fluctuations in UDP data transmission caused by interruption of TCP data transmission during continuous data transmission by UDP can be reduced, so real-time performance is required. The quality of the communication service to be performed can be improved. In addition, when the amount of UDP data transmission decreases, the control of eliminating the restriction on the bandwidth used in the data transmission by TCP can improve the bandwidth utilization efficiency of the network.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration example of a communication system to which a bandwidth control method according to the present invention is applied.

FIG. 2 is a diagram showing an embodiment of a software configuration provided in the customer computer shown in FIG.

FIG. 3 is a diagram showing a TCP header configuration used in data transmission by TCP.

FIG. 4 is a sequence diagram showing one embodiment of a band control process in the customer computer.

FIG. 5 is a sequence diagram showing another embodiment of the band control process in the customer computer.

[Description of Signs] 100: Computer for customer, 101: IP (Inte
rnet Protocol (network) 102, operator terminal 103, CTI (Computer Telep)
honey Integration) server, 104 ...
LAN (Local Area Network), 1
05: eb server, 200: main control unit, 201: UDP
Data transmission amount monitoring unit, 202 ... communication bandwidth control unit, 20
3 ... voice communication control interface, 204 ... WW browser interface.

Claims (8)

[Claims] 1. A step of monitoring a UDP data transmission amount between devices capable of executing data transmission by TCP and UDP in parallel on an IP network, and a window of the TCP being transmitted along with a change in the UDP data transmission amount. Changing the size to control the bandwidth used for the TCP data transmission. 2. A communication system between devices connected on an IP network.
Monitoring the amount of UDP data transmission when the data transmission by CP and UDP is performed in parallel;
Controlling the network bandwidth by dynamically changing the window size of the TCP as the amount of DP data transmission increases or decreases.
A bandwidth control method characterized by reducing fluctuations caused by data transmission by means of (1) and realizing an effective bandwidth. 3. The bandwidth control method according to claim 2, wherein
The step of monitoring the amount of transmitted UDP data includes measuring the amount of received UDP data within a certain period of time, and increasing or decreasing the amount of transmitted UDP data depending on whether the measured value is equal to or greater than a preset threshold value or less than the threshold value. A bandwidth control method comprising: 4. The bandwidth control method according to claim 2, wherein
The step of dynamically changing the window size of the TCP includes holding in advance each window size setting value corresponding to the increase / decrease of the UDP data transmission amount,
Along with the determination of the increase or decrease of the DP data transmission amount, a window size setting value corresponding to the increase or decrease of the UDP data transmission amount is selected, and the current window size of the TCP is set to the selected window size setting value. A bandwidth control method characterized by changing. 5. A monitoring unit for monitoring a UDP data transmission amount between devices capable of executing data transmission by TCP and UDP in parallel on an IP network, and a monitoring unit for the TCP data transmission according to a change in the UDP data transmission amount. A bandwidth control unit for controlling a bandwidth used for the TCP data transmission by changing a window size. 6. When data transmission by TCP and UDP is performed in parallel between devices connected on an IP network,
A monitoring unit that monitors a UDP data transmission amount, and a bandwidth control unit that controls a network bandwidth by dynamically changing a window size of the TCP according to the increase or decrease of the UDP data transmission amount; A bandwidth control device, which reduces fluctuations generated by data transmission between said devices by said UDP and realizes effective band securing. 7. The bandwidth control device according to claim 6, wherein:
The monitoring unit that monitors the amount of transmitted UDP data measures the amount of received UDP data within a certain period of time, and determines whether the amount of received UDP data is equal to or greater than a preset threshold value or less than a predetermined threshold value. A bandwidth control device for determining increase or decrease. 8. The bandwidth control device according to claim 6, wherein
The bandwidth control unit that dynamically changes the window size of the TCP has a window size setting value corresponding to an increase / decrease of the UDP data transmission amount in advance,
With the determination of the increase or decrease of the UDP data transmission amount,
A bandwidth control device for selecting a window size setting value corresponding to an increase or a decrease in a data transmission amount, and changing a current window size of the TCP to the selected window size setting value.