隨著開放式架構的發展，ORAN架構被提出作為5G以及未來6G網路的基礎:傳統的無線電存取網路(Radio Access Network, RAN)將天線以及信號處理單元整合成硬體的基地台，所以掌控權完全在電信設備提供商手中，且不同供應商生產的RAN設備沒辦法相互溝通，無形中限制了4G網路的發展。
ORAN是一個建構於以往3GPP協定的開放式無線電存取網路架構。ORAN因其開放式的架構，斬斷了以往由特定廠商壟斷行動通訊元件市場，降低總體網路建置的成本; RAN功能軟體化後搭配ORAN元件AI及機器學習更可根據情況提供更好的網路資源配置以達到更好的效能。
ORAN架構中，xAPP被部署在近及時控制器，提供數據監控以及無限資源管理(RRM)。由於ORAN開源化，架構也較以往傳統RAN更為複雜，各個介面跟資料傳輸管道都有可能面臨資安風險。本研究將著重xAPP的E2介面，針對E2節點與RIC元件的封包傳輸進行監控，並利用單類別SVM模型進行異常偵測，而實驗結果也呈現了本研究架構的可行性。

With the development of open architecture, the ORAN framework has been proposed as the foundation for 5G and future 6G communication networks. The traditional radio access network (RAN) integrates antennas and signal processing units into hardware base stations, resulting in complete control by telecommunications equipment providers. In addition, lack of interoperability among RAN equipment from different vendors has inadvertently limited the advancement of 4G networks.
ORAN stands for Open Radio Access Network, an architecture built upon previous 3GPP protocols. It breaks the monopoly of specific vendors in the mobile communication component market, thereby reducing overall network deployment costs. With RAN function virtualization coupling with AI and machine learning within ORAN components, better network resource allocation and improved performance can be achieved.
Within the ORAN architecture, xAPP is deployed in the near real-time controller, providing data monitoring and Radio Resource Management (RRM). Due to the open nature of ORAN, the architecture is more complex compared to traditional RAN, and various interfaces and data transmission channels may face cybersecurity risks. This research focuses on the E2 interface of xAPP, monitors packet transmission between E2 nodes and RIC components, and utilizes One-Class SVM models for anomaly detection. The experimental results also demonstrate the feasibility of the research framework proposed in this study.

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