植基於流量訊息之網路負載平衡系統

A Network Load Balance System Based on Flow Information

高宇帆(Yu-Fan Kao)

指導教授 ： 包蒼龍

大同大學/電機資訊學院/資訊工程學系所/碩士(2004年)

摘要

網路的各種應用快速成長，對於網路頻寬的需求也日益增加，現在已經從單純的傳輸文字及影像進展到即時的影音娛樂，而線上遊戲的發展更是如日中天，隨之而來的是必須面臨頻寬不足的問題。由於現在的寬頻網路十分便宜，除了向ISP要求提升自身的上網頻寬，還可以在本來的對外線路外，再向ISP增加幾條對外線路以增加頻寬。
另外，由於TCP/IP通訊協定的特性，如果網路中有某個使用者在傳輸檔案或進行其他的行為佔用掉大部分的頻寬，則其他的使用者就只能分享剩餘的頻寬。這對於打算進行VoIP或是其他影音服務的使用者而言，會造成不舒服的延遲，或是封包漏失等現象，這種不公平的情況也必須加以控制。
增加對外線路除了可以擴展對外頻寬，當某個ISP發生問題時，使用者仍然可以透過另一個ISP繼續上網，不必苦等ISP修復。不過目前支援多線負載平衡的網路設備仍十分昂貴，本篇論文提出一個利用Linux穩定及便宜的特性，架設具備負載平衡的系統，負責將流量分散到可用的對外線路上，並提供流量管理，藉由管理控制內部電腦對於對外頻寬的利用度，建立一個公平的網路環境。

關鍵字

流量 ； 負載平衡

並列摘要

Because of the rapid growth of applications in internet, the demand of network bandwidth has increased drastically. Transmitting data over network have moved from traditional text to multimedia, and the bandwidth is consumed very fast. To solve the bandwidth problem, we can install higher bandwidth outbound line or add more outbound lines to the ISP.
Besides, TCP/IP protocol provides services at “best-effort” level. If someone transfers big files or other process that occupy a lot of bandwidth, other users can only share the remaining bandwidth. This will cause delay or packet loss to users who want to use VoIP or other multimedia services. This unfair situation must be controlled, too.
Add another outbound line is an inexpensive solution. And if one ISP has problem, we can still access the internet via the remaining line. However, the equipment support multi-line outbound interfaces are quite expensive. This thesis utilizes the Linux operating system to build a router which support load balance and bandwidth management. The internal hosts access the internet via this router. The traffic of them will be split evenly to into all the outbound lines. We also provide bandwidth management to accomplish fair network utilization.

並列關鍵字

load balance ； netflow

參考文獻

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[2]Yong Tang, Chengjie Mao, Hai-Xiang Ou, Xue-Liang Yang nad Xianji Li, “Research on adaptive IP QoS management framework”, Computer Supported Cooperative Work in Design, The Sixth International Conference on, 2001 , 12-14 July 2001.