軟體定義網路(SDN)是一種新型態的網路架構， 將傳統分散式的網路控制架構轉為集中式的控制架構並可藉此提供網路更多創新的靈活性。本文提出基於SDN式的虛擬網路應用及其實現方式， 並和非SDN式虛擬網路進行比較。非SDN式虛擬網路中透過Spanning Tree Protocol建立生產樹後再進行網路傳輸， 導致備援鏈結閒置並造成資源使用率不佳。在SDN式虛擬網路中， 我們在 OpenDaylight控制器中開發兩個模組， 分別負責找出disjoint的鏈結演算法與其鏈結使用策略。最後， 證明在full mesh 的網路架構中該演算法可以找出全部不相交的鏈結。

Software Defined Network (SDN) is a new network arch itecture, which separates the control plane from the data plane and is able to provide new flexibilities in network innovation . In this article, an SDN-enable virtual network application is proposed and compared with the non-SDN virtual network. Based on OpenDaylight controller framework, two plug-ins, compute multi path bundle and policy manager, are designed to find out possible disjoint link and determining the links usage, respectively. Finally, an algorithm is proposed and proved that it can decide all available disjoint links in a full mesh network topology.