軟體定義網路是一個新興且快速發展的網路架構，而Segment Routing則是定義利用封包標頭中的MPLS標籤欄位來表示封包的路由資訊。透過軟體定義網路與Segment Routing的結合應用，使軟體定義網路的路由管理更加有效率與簡單化並且解決在軟體定義網路中所遇到的可擴展性議題。我們提出一個啟發式的演算法使之應用在軟體定義網路與Segment Routing的環境中。演算法的目標為替網路單點傳輸要求提供一條滿足頻寬需求的路由資訊，同時可以平衡網路流量負載與避免因為封包標頭中MPLS標籤的增加所造成網路額外的傳輸成本。我們的演算法考慮了網路鏈接的重要性與其剩餘頻寬來設計網路鏈接的權重，並且限制封包標頭中標籤的個數來節省網路資源。模擬結果顯示我們所提出的演算法之於其他演算法在多個不同大小的網路拓樸下皆可以容納更多的流量需求與達到更好的網路吞吐量。

Software-Defined Networking (SDN) is an emerging architecture and it offers advantages over traditional network architecture. Segment Routing (SR) defines the path information through the network via an ordered list of MPLS labels on the packet header at the ingress device and makes SDN routing management more efficient and simple. It can also solve some scalability issues in SDN. In this thesis, we propose a routing algorithm for SDN with SR to serve the bandwidth requirement of a routing request. Our algorithm considers the balance of traffic load and reduces the extra cost of the packet header size in a network. Simulation results show that the performance of our algorithm is better than previous work in terms of average network throughput and average rejection rate of routing requests.

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