隨著科技的快速成長，各式新興應用相繼出現，不同網路服務產生了各種不同的需求，卻是由同一實體網路提供，傳統網路不再能負荷各種極端需求的新興應用，因此網路切片的概念誕生了，在一共享的實體網路中，提供邏輯上獨立的客製化網路切片給不同應用，其較靈活部署網路服務的方式，改善了傳統網路的缺點。軟體定義網路和網路功能虛擬化都是實現網路切片關鍵技術，軟體定義網路將網路層從資料層中分離，邏輯上集中的控制器，提供了可編程性，可以更彈性實現各種應用如故障管理。而網路功能虛擬化將網路功能從專用硬體中抽出，使虛擬化後的網路功能可更彈性的在通用型伺服器上動態部署和管理。

本論文基於軟體定義網路的環境中，實作網路切片之縮放功能和退役功能，加入切片等級制度，於系統資源告急時可以容納更多切片需求，中央編排藉由向網域控制器收集資料後進行決策。本論文利用多控制器分化不同控制層之工作來實作故障管理，當網路故障發生時，由負責備援路徑之控制器來進行備援路徑的建立。實驗結果顯示，本論文加入之功能確實能滿足承租戶之調整切片和終止切片之要求，並在資源告急時對優先權較低之切片作出調整，在脫離資源告急狀態時補償被犧牲之切片，以及能在網路故障發生時確實進行路徑遷移以因應該次故障事件發生。

With the rapid growth of network technology, kinds of emerging applications appeared. Different network services have their own requirements but share the same physical infrastructure. Since traditional network architecture could not load emerging applications with extreme demands, the concept of network slicing was born. Network slicing allows to create logically isolated customized slices for different applications on a shared physical network. The enabler technologies of network slicing like Software-Defined Networking(SDN) and Network Function Virtualization(NFV) have a more resilient way to configure and manage network, and improve the shortcomings of traditional networks. SDN separates control plane and data plane to form a logically centralized controller, providing programmability to make more flexible implementation of various applications such as fault management. NFV turns the network functions originally deployed on dedicated hardware to be softwarized, making virtualized network functions have a more flexible way to be dynamically configured and managed on standard servers.

This thesis designed a network slicing lifecycle management in SDN environment including the scaling function and decommissioning phase of slices. Moreover, it introduced a slice level institution to accommodate more slice requirements. Orchestrator collect information from core controllers to make decisions. This work implements a fault management mechanism leveraged with multiple controllers to split different tasks. While network fault occurs, the controller who is responsible for backup path installs the rules of backup path. The result shows that the functions this work implements are able to fulfill the requests to adjust a slice or delete a slice from tenants, sacrifice the resource of low priority slices in resource emergency condition, compensate resource to the sacrificed slices while out of resource emergency condition. And it can indeed migrate traffic when network failure occurs in response to the network fault event.

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