LoRaWAN被視為低功率廣域網路技術之中較具有潛力的協定，近期基於LoRa的研究與應用逐漸被提出。其中有研究針對LoRa是否真的適合用於大量裝置的物聯網建置提出疑問並探討。針對此新型的通訊技術所能承受的容量與信賴度值得研究。本論文針對LoRa的封包傳送之間的安全性提出受到干擾攻擊的可能性，透過一般市面上可得的LoRa模組實作出反應式阻斷攻擊器，並藉由實驗評估此攻擊器對LoRaWAN的影響程度。在攻擊器部分，本論文分別對於反應與阻斷的方面進行探討，根據實驗將參數的設定做優化設計，並提出利用LoRa調變的非正交特性來進行阻斷攻擊。本論文所提出的反應式阻斷攻擊器，可以套用在任何使用LoRa收發模組的裝置上，針對單一頻道固定傳送速率的封包進行阻斷攻擊，使得閘道器無法接收受到阻斷攻擊的封包。本論文透過實際的實驗模擬受到阻斷攻擊的LoRaWAN，評估攻擊的影響程度。實驗結果證實LoRa無線通訊技術確實會受到非正交訊號的阻斷攻擊，做為未來LoRaWAN建置的安全性參考。

LoRaWAN has be seen as the one of most potential protocol in Low Power Wide Area Network (LPWAN). The researches and applications have been studied in recent published work. Face to the huge requirements of communication in the wide coverage, LoRaWAN is doubted on the capacity and reliability. In this paper we evaluate the potential jamming threat in LoRaWAN. By means of jamming attack aiming to LoRa technology. We pretend an attacker who intend to create a jammer based on LoRa transceiver and degrade the transmission reliability. We figure out the proper setting on jammer by presenting three experiments. We characterize the effect of jamming by implementing reactive jammer in built up LoRa devices. Importantly, the presented results on jamming effect provide new security consideration for ap-plication deployment.

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