KR20100132776A - Method for controlling bandwidth based on flow at network device - Google Patents

Abstract

PURPOSE: A method is provided to improve the quality of a subscriber by guaranteeing the equal use of a bandwidth for a subscriber. CONSTITUTION: A flow information is extracted about a packet passing a network device(210). A flow is classified based on the source or destination IP of the extracted flow information(220). A bandwidth, which is allocated according to the source or the destination IP, is calculated based on the available bandwidth of the physical interface of the network device(230). The bandwidth, which is assigned to each flow, is calculated based on the classified result and the calculated bandwidth(240). A bandwidth is allocated to each flow according to the calculated bandwidth(250).

Description

Method for controlling bandwidth based on flow at network device}

The present invention relates to traffic control in a network, and more particularly, to a method of controlling bandwidth on a flow basis in a network device.

In general, service providers use rate-limit based on IP in controlling subscriber bandwidth. This type of speed control limits the amount of bandwidth not exceeded based on the total amount. However, this type of rate limiting has no effect on the subscribers who have not exceeded the contracted bandwidth even if congestion occurs due to the traffic explosion, and ultimately cannot solve the bandwidth imbalance used by the subscribers.

Congestion in the network is usually due to the small number of subscribers generating large amounts of traffic. However, most network devices use random early detection (RED) to control bandwidth by dropping packets. When discarding a packet by RED, all packets are discarded with the same probability, so that a packet of a user who uses a relatively low bandwidth can be discarded. As a result, the bandwidth used by all users is reduced overall, and a small number of subscribers still occupy a relatively large amount of bandwidth. The problem of traffic control is that the service such as the large download of a small number of subscribers that are not sensitive to delay can cause delays and loss sensitive packets such as the web, VoIP, and IP-TV, thereby degrading subscribers' quality of Internet service. will be.

By taking advantage of these characteristics of Internet traffic, peer-to-peer applications generate a lot of flows, occupying a relatively large amount of bandwidth, increasing performance and reliability. As a result, users who do not use peer-to-peer applications are forced to use relatively little bandwidth.

An object of the present invention is to provide a flow-based bandwidth control method for ensuring a fair bandwidth for each subscriber in an environment in which flow information is maintained.

According to an aspect of the present invention, there is provided a method of controlling a bandwidth based on a flow in a network device, the method including: (a) extracting flow information on a packet passing through the network device; (b) classifying flows based on the source or destination IP of the extracted flow information; (c) calculating a bandwidth to be allocated for each source or destination IP based on the available bandwidth of the physical interface of the network device; (d) calculating a bandwidth to be allocated to each flow based on the bandwidth calculated in step (c) and the result classified in step (b); And (e) allocating bandwidth to each flow according to the bandwidth calculated in step (d).

Here, the steps (a) to (e) is preferably performed repeatedly according to a predetermined period.

And step (c), it is preferable to calculate so that the available bandwidth is evenly distributed to the source or destination IP.

Further, in calculating the bandwidth to be allocated for each flow having any source or destination IP in step (d), the bandwidth calculated in step (c) is equally distributed to the flow having the source or destination IP. It is desirable to calculate as much as possible.

According to an aspect of the present invention, there is provided a method for controlling bandwidth based on a flow in a network device, the method comprising: (a) extracting flow information on a packet passing through the network device; (b) classifying flows based on the source or destination IP of the extracted flow information; (c) grouping flows by subscriber receivers using the destination or source IP of the extracted flow information; (d) calculating a bandwidth to be allocated for each source or destination IP connected with the subscriber accommodation device based on the available bandwidth of the physical interface between the aggregation network device and the subscriber accommodation device; (e) calculating a bandwidth to be allocated to each flow based on the bandwidth calculated in step (d) and the result classified in step (b); And (f) allocating bandwidth to each flow according to the bandwidth calculated in step (e).

According to the present invention described above, it is ensured that an equal bandwidth can be used for each subscriber in an environment in which flow information is maintained. Therefore, subscribers can use the bandwidth fairly and can improve the quality of subscribers' experience as a whole.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description and the accompanying drawings, substantially the same components are denoted by the same reference numerals, and redundant description will be omitted. In addition, in the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

According to the present invention, a network apparatus for performing the flow-based bandwidth control method proposed in the present invention is provided in a path through which traffic is distributed on a network. Hereinafter, a network device that performs the flow-based bandwidth control method according to the present invention will be referred to as a "flow-based network device" for convenience.

1 is a reference diagram illustrating a form in which a flow-based network device according to an embodiment of the present invention is provided on a network.

In one embodiment, the flow-based network device 101 may be provided between the operator network side and the network device 102 to which the subscriber 104 is connected, as shown. Network device 102 may be, for example, a router or a switch.

In another embodiment, the flow-based network device 102 may be provided between the network device 102 on the operator network side and the aggregation network device 107 having several subscriber receivers 108 as shown. The aggregation network device 107 can be, for example, an L2 switch or an L3 switch.

The flow-based network apparatuses 101 and 102 extract flow information from packets passing through the apparatus and allocate bandwidth to each flow based on the flow information. In the present embodiment, a flow refers to a source IP address, a destination IP address, a source port, and a destination port for packets constituting Internet traffic. In other words, it refers to a unit of end-to-end traffic specified by using five attributes of a protocol as an identifier. The flow information refers to the above-described source IP address, destination IP address, source port, destination port, and protocol. The flow-based network devices 101 and 102 may provide the above functions through interworking with a separate external interworking system 103 according to a network configuration or traffic management purpose. The external interworking system 103 may be, for example, a network management system (NMS).

The flow-based network device 101 extracts flow information from packets passing through the device and allocates bandwidth to each flow based on the same in order to ensure that the bandwidth is equally used for each subscriber. To this end, the flow-based network device 101 extracts flow information by referring to header information of packets flowing out (or flowing) from the device 101 at an arbitrary time point, and extracts the extracted flow information into a table form, for example. Has the ability to manage and maintain This flow information table maintains flow information of all flows found at that time. Extraction of such flow information may be repeatedly performed at any period, and the flow information table may be updated each time.

2 is a flowchart illustrating an embodiment of a method of controlling bandwidth on a flow basis in the flow based network apparatus 101. This embodiment will be described on the assumption that bandwidth is controlled based on download traffic.

In step 210, the flow information is extracted with reference to the header information of the packet with respect to the packets passing through the flow-based network device 101. In this step, the flow information may be extracted by monitoring the packet flowing out through the link of the device 101 and analyzing the header of the monitored packet. The flow information table is updated according to the extracted flow information.

Next, in step 220, the flow is classified based on the destination IP of the extracted flow information. That is, flows having the same destination IP are classified among all flows held in the flow information table. Since the destination IP serves as a criterion for identifying the subscriber, the subscriber corresponding to the destination of all traffic passing through the device 101 is defined at the time when the flow information is extracted through this step, and several flows toward each destination IP are defined. Is defined.

Next, in step 230, the bandwidth to be allocated to the destination IP generated as a result of the flow classification in step 220 is calculated based on the available bandwidth of the physical interface through which the traffic is distributed, connected to the network device 101. Here, the available bandwidth is calculated to be equally distributed for each destination IP. For example, if the available bandwidth of the physical interface between the flow-based network device 101 and the network device 102 is 1 Gbps, and 20 destination IPs are generated as a result of flow classification in step 220, the calculated bandwidth is 1 Gbps / 20. = 50 Mbps.

Next, in step 240, the bandwidth to be allocated to each flow is calculated based on the bandwidth for each destination IP calculated in step 230 and the result classified in step 220, that is, how many flows exist for each destination IP. Here, in calculating the bandwidth to be allocated to each flow having an arbitrary destination IP, the bandwidth is equally distributed to each flow with the bandwidth for the destination IP calculated in step 230. That is, the bandwidth calculated in step 230 is divided by the number of flows having the corresponding destination IP. For example, if the bandwidth calculated for the destination IP is 50 Mbps and the number of flows having a certain destination IP is 10, then the bandwidth to be allocated to each calculated flow is 50 Mbps / 10 = 5 Mbps.

Next, in step 250, bandwidth is allocated to each flow according to the bandwidth calculated in step 240. As a result, each subscriber occupies the same bandwidth, and flows toward the same subscriber also occupy the same bandwidth.

Next, the process proceeds to step 260, when a predetermined time elapses, the process returns to step 210 again and repeats the steps 210 to 250. In the Internet environment, flows are created and destroyed at any time, so that the bandwidth allocated for each flow in the past time does not effectively reflect the traffic state at the present time. Therefore, in the present embodiment, the above-described process is repeatedly performed at regular intervals so that bandwidth can be used evenly for each subscriber in real time. The execution cycle may be set in advance, for example, several seconds. The shorter the set time, the more accurately the bandwidth control can be performed according to the traffic conditions changing in real time. However, an appropriate value may be set in consideration of the performance of the flow-based network device 101 or the characteristics of the traffic.

The above-described embodiment has been described on the assumption that bandwidth is controlled based on download traffic. Of course, the bandwidth can be controlled based on the upload traffic. In this case, the flow is classified in step 220 based on the source IP, and in step 230, the bandwidth to be allocated for each source IP is calculated.

3 is a flow diagram illustrating one embodiment of a method for controlling bandwidth on a flow basis in a flow based network device 106. This embodiment will also be described on the assumption that bandwidth is controlled based on download traffic.

Unlike the network device 102, the flow-based network device 106 is provided between the network device 102 on the operator network side and the aggregation network device 107 having several subscriber receivers 108 as shown. When the flow-based network device 106 controls bandwidth on a flow-by-flow basis above the aggregation network as in this embodiment, since the physical interface between the aggregation network device 107 and the subscriber accommodating device 108 cannot be recognized directly, Additional procedures are required to ensure fair use of bandwidth as compared to the embodiment described in FIG.

In step 310, flow information is extracted for packets passing through the flow-based network device 106, and in step 320, flows are classified based on a destination IP of the extracted flow information. Steps 310 and 320 are the same as steps 210 and 220 described above, so a detailed description thereof will be omitted.

In step 330, flows are grouped by subscriber receiving apparatus using the destination IP of the extracted flow information. Here, the IPs of subscribers connected to each subscriber receiver 108 are predefined, and the flow-based network device 106 may have information about it in advance or may be transmitted from another network device. The information may be, for example, an IP list of subscribers connected to each subscriber receptacle 108. The flow-based network device 106 may refer to this information to group flows by subscriber receiving device 108 using the destination IP of the flow information.

In operation 340, the bandwidth to be allocated for each destination IP connected to each subscriber receiver 108 is calculated based on the available bandwidth of the physical interface between the aggregation network device 107 and each subscriber receiver 108. Information about the available bandwidth of the physical interface between the aggregation network device 107 and each subscriber receptacle 108 may have in advance the flow-based network device 106 or may be communicated from another network device. Here, the available bandwidth is calculated to be equally distributed to the destination IP for each subscriber receiving device 108.

For example, the available bandwidth of the physical interface between the aggregation network device 107 and the first subscriber receptacle 108 is 2 Gbps, and the available bandwidth of the physical interface between the aggregation network device 107 and the second subscriber receptacle 108 is 1 Gbps. If 50 and 20 destination IPs are generated as a result of the grouping in step 330, the bandwidth calculated for each destination IP for the first subscriber receiver 108 is 2Gbps / 50 = 40Mbps, and the second subscriber is accommodated. For device 108, the bandwidth calculated for each destination IP is 1Gbps / 20 = 50Mbps.

In operation 350, the bandwidth to be allocated to each flow is calculated based on the bandwidth for each destination IP calculated in operation 340 and the result classified in operation 320, that is, how many flows exist for each destination IP. Here, in calculating the bandwidth to be allocated to each flow having an arbitrary destination IP, the bandwidth is equally distributed to each flow with the bandwidth for the destination IP calculated in step 340. That is, the bandwidth calculated in step 340 is divided by the number of flows having the corresponding destination IP.

Next, in step 360, bandwidth is allocated to each flow according to the bandwidth calculated in step 350. As a result, each subscriber connected to the same subscriber receiving apparatus 108 occupies the same bandwidth, and flows destined for the same subscriber also occupy the same bandwidth.

Like the embodiment described with reference to FIG. 2, the process proceeds to step 370, and when a predetermined time elapses, the process returns to step 310 again and repeats steps 310 to 360.

The above-described embodiment has been described on the premise that the bandwidth is controlled based on the download traffic, as in the embodiment described with reference to FIG. 2. In addition, the bandwidth may be controlled based on the upload traffic. In this case, in step 320, the flow may be classified based on the source IP, and in step 340, the bandwidth to be allocated for each source IP may be calculated.

Meanwhile, the above-described embodiments of the present invention can be written as a program that can be executed in a computer, and can be implemented in a general-purpose digital computer that operates the program using a computer-readable recording medium. The computer-readable recording medium may include a magnetic storage medium (eg, ROM, floppy disk, hard disk, etc.), an optical reading medium (eg, CD-ROM, DVD, etc.) and a carrier wave (eg, internet Storage medium).

So far I looked at the center of the preferred embodiment for the present invention. Those skilled in the art will appreciate that the present invention can be implemented in a modified form without departing from the essential features of the present invention. Therefore, the disclosed embodiments should be considered in an illustrative rather than a restrictive sense. The scope of the present invention is shown in the claims rather than the foregoing description, and all differences within the scope will be construed as being included in the present invention.

1 is a reference diagram illustrating a form in which a flow-based network device according to an embodiment of the present invention is provided on a network.

2 is a flowchart illustrating an embodiment of a method of controlling bandwidth on a flow basis in the flow based network apparatus 101.

3 is a flow diagram illustrating one embodiment of a method for controlling bandwidth on a flow basis in a flow based network device 106.

Claims (8)

A method of controlling bandwidth on a flow basis in a network device, (a) extracting flow information on the packet passing through the network device; (b) classifying flows based on the source or destination IP of the extracted flow information; (c) calculating a bandwidth to be allocated for each source or destination IP based on the available bandwidth of the physical interface of the network device; (d) calculating a bandwidth to be allocated to each flow based on the bandwidth calculated in step (c) and the result classified in step (b); And (e) allocating bandwidth to each flow according to the bandwidth calculated in step (d). The method of claim 1, The steps of (a) to (e) are performed repeatedly according to a predetermined cycle flow-based bandwidth control method. The method of claim 1, In step (c), the bandwidth is calculated so that the available bandwidth is evenly distributed to the source or destination IP. The method of claim 1, In calculating the bandwidth to be allocated for each flow having any source or destination IP in step (d), the bandwidth calculated in step (c) is calculated to be equally distributed to the flow having the source or destination IP. Flow-based dynamic bandwidth allocation method characterized in that the. A method of controlling bandwidth on a flow basis in a network device, (a) extracting flow information on the packet passing through the network device; (b) classifying flows based on the source or destination IP of the extracted flow information; (c) grouping flows by subscriber receivers using the destination or source IP of the extracted flow information; (d) calculating a bandwidth to be allocated for each source or destination IP connected with the subscriber accommodation device based on the available bandwidth of the physical interface between the aggregation network device and the subscriber accommodation device; (e) calculating a bandwidth to be allocated to each flow based on the bandwidth calculated in step (d) and the result classified in step (b); And (f) assigning bandwidth to each flow according to the bandwidth calculated in step (e). The method of claim 5, The steps (a) to (f) are repeatedly performed according to a predetermined cycle. The method of claim 5, In step (d), the bandwidth is calculated so that the available bandwidth is evenly distributed to the source or destination IP. The method of claim 5, In calculating the bandwidth to be allocated for each flow having any source or destination IP in step (e), the bandwidth calculated in step (d) is calculated to be equally distributed to the flow having the source or destination IP. Flow-based dynamic bandwidth allocation method characterized in that the.

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