隨著網際網路的快速發展，如何有效分配與管理無線網路頻寬，以達到較高服務品質，是當前急需解決之課題。現今的網路架構中，需要在大量的網路設備上，手動設定頻寬固有規則；設定上的複雜度、需要設定的網路設備數量、以及網路管理員專業知識不足，很容易出現因人為錯誤而導致服務中斷，或是僅能提供粗糙服務品質的保證。且市售之網路設備，其軟硬體架構多為封閉式，研究人員無法修改底層架構，僅能於上層做應用服務的設計與開發。

因此，本研究利用嵌入式系統與開放式OpenWrt平台，加上OpenFlow之網路架構，建構一開放式無線網路環境，並於此環境驗證本研究所提出之動態頻寬管理策略機制。首先，本研究於各網路節點上，對頻寬使用率、以及各節點下使用者之應用程式種類數量，進行監控與分析；接著，依據上述的評估，對各節點配予得分分數；最後，經由比例計算，變更網路頻寬之分配情形。根據研究結果顯示，本研究所提出的SDN-DBM動態頻寬分配機制，與未使用本機制之嵌入式設備互相比較下，能有效提升網路頻寬使用率12.4%。

With rapid development of the internet, it’s an imperious task to arrange and manage wireless bandwidth effectively. In today’s network architecture, it is needed to set bandwidth control rules manually on lots of network equipment. Human error can be easily caused by the complicated setting method, the large amount of equipment, and the lack of professional knowledge of network manager. Moreover, closed systems of most network devices allows researchers to merely develop applications on the top layer rather than modify the architecture on the bottom layer.

This work provides a mechanism of dynamic bandwidth management and verify it on an open wireless environment by using OpenWrt platform with OpenFlow network architecture. First, this work monitors and analyses bandwidth situation of each network node. The number and types of currently executing applications of users on each network node are also monitored. Second, according to the evaluation as mentioned above, this work assigns a number as index weight to each device. Finally, according to the weight ratio, this work reallocate bandwidth distribution. Based on the results obtained, this work improves bandwidth utilization by 12.4%.

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