隨著網路技術發展，智慧城市、智慧家庭、工業4.0等越來越多物聯網應用被提出。物聯網屬於low-power and lossy networks (LLNs)，RPL(Routing Protocol for Low-Power and Lossy Networks)[1]是針對LLNs所設計之路由協定，然而RPL缺少了因應災難等緊急狀況時，網路節點短時間內大量毀損的路由機制。此篇論文首先分析了災難事件對RPL的效能影響，包含封包送達率及end-to-end延遲。同時也提出新的災難緊急路由機制Emergency RPL(EMRPL)，預先計算得以避開危險區域的路由，以降低修復機制觸發次數。並且減少不必要的鄰節點通訊及冗餘的區域修復，進而在災害事件中維持整體效能。

With the development of network technology, more and more Internet of Things (IOT) applications, such as smart cities, smart homes, and industrial 4.0 have been proposed. IOT is a low-power and lossy networks (LLNs). The RPL (Routing Protocol for Low-Power and Lossy Networks) is a routing protocol designed for LLNs. However, RPL is not applicable for disasters when there are a large number of nodes crashed in a short period of time. This paper first analyzes the impact of disaster events on RPL, including packet delivery rates and end-to-end delays. At the same time, a new disaster emergency routing mechanism, Emergency RPL (EMRPL), is proposed to pre-calculate routes that avoid dangerous areas to reduce the number of repair mechanism triggers. It also reduces unnecessary neighbor communication and redundant area repairs to maintain overall performance during disaster events.

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