由於近期使用者雲端服務應用的需求急遽上升，雲端服務企業紛紛建造大型的資料中心，在資料中心裡降低封包延遲時間和平衡資料中心線路的流量是兩個重要的議題。隨著軟體定義網路的蓬勃發展，軟體定義網路已成為研究者們解決網路問題重要的一部分。因此，本論文採用軟體定義網路集中式的架構，並設計有效率的繞徑演算法來解決上述兩個問題。在本論文我們提出四個演算法，第一個為最短路徑優先演算法，在此演算法中，我們會在網路中找一條剩餘頻寬最大的最短路徑來傳送資料。第二個演算法為頻寬感知繞徑演算法，此演算法目的在於找出一條剩餘頻寬最大的路徑，如果有多條剩餘頻寬最大的路徑存在，則選擇當中最短的路徑。第三與第四個演算法分別為第一與第二個演算法的延伸，在第三個演算法中，我們會找出前k條最短路徑，然後在選擇其中剩餘頻寬最大的路徑。第四個演算法則是找出前k條實驗表明剩餘頻寬最大的路徑，然後在選擇其中的最短路徑。實驗結果，相對於傳統的有線網路傳輸協定，本論文的方法可大幅提昇網路的利用率和降低使用者需求無法滿足的比率。

Abstract iv
List of Contents v
Chapter 1 Introduction 1
Chapter 2 Preliminary 4
Chapter 3 Routing Algorithms 9
3.1 Shortest Path First (SPF) Algorithm 9
3.2 Bandwidth Aware Routing (BAR) Algorithm 11
3.3 k-SPF algorithm 14
Chapter 4 Performance Evaluation 20
4.1 Traffic Pattern & Measurement 20
4.2 Simulation Results 21
Chapter 5 Conclusion 28

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