車聯網（Internet of Vehicles， IoV）與智慧交通系統的發展，使車輛、邊緣節點與雲端平台之間需要進行大量且即時的資料共享。然而，IoV 環境具有節點高度移動、通訊開放、資料量龐大與跨管理域授權等特性，使機密性、細粒度存取控制、密文資料可用性、後量子安全性與車載終端運算負擔成為安全資料共享中的重要挑戰。 為回應上述問題，本研究提出一套基於 Ring-LWE 之多授權機構屬性基密文檢索系統，應用於 IoV 大型資料共享場景。本文以道路影片作為主要資料型態，結合混合式資料保護、密文檢索與邊緣輔助機制，使資料能在加密狀態下完成授權共享與查詢，同時降低大型資料直接由屬性基機制處理所造成的計算與傳輸負擔，並減少車載資料使用者端之解密成本。 本研究從正確性、安全性、理論複雜度、實作效能與 SUMO 車聯網情境模擬等面向評估所提方案。分析結果顯示，本文方案可支援授權資料使用者正確完成密文檢索與解密流程，並能抵抗未授權解密與跨使用者金鑰拼湊攻擊。在 0.5 MB 與 1 MB 道路影片之上傳與下載情境下，本文方案可維持秒級延遲；於車輛數量由 100 增加至 400 的模擬環境中，仍能維持約 86%–87% 的資料接收進度，且下載情境之平均封包遺失率約為 0.2185%。整體而言，本文方案能在後量子安全、授權功能完整性與車載終端輕量化之間取得平衡，並提升 IoV 大型資料共享於移動網路環境中的可部署性。;With the development of the Internet of Vehicles (IoV) and intelligent transportation systems， secure and efficient data sharing among vehicles， edge nodes， and cloud platforms has become increasingly important. However， high node mobility， open communication environments， massive data volumes， and cross-domain authorization requirements make it difficult to simultaneously achieve confidentiality， fine-grained access control， ciphertext usability， post-quantum security， and lightweight terminal computation. To address these challenges， this study proposes a Ring-LWE-based multi-authority attribute-based ciphertext retrieval scheme for secure large-scale data sharing in IoV environments. Focusing on road video sharing， the proposed scheme integrates hybrid data protection， ciphertext retrieval， and edge-assisted processing. Large payloads are encrypted using symmetric encryption， while Ring-LWE-based attribute-based mechanisms are used for access control and key protection， thereby reducing the computation and transmission overhead caused by directly applying attribute-based encryption to large data. The proposed scheme is evaluated through correctness and security analyses， theoretical complexity analysis， implementation experiments， and SUMO-based IoV simulations. The results show that the scheme supports correct ciphertext retrieval and decryption for authorized users， while resisting unauthorized decryption and cross-user key-collusion attacks. For 0.5 MB and 1 MB road video payloads， the scheme achieves second-level latency in both upload and download scenarios. Under vehicle densities ranging from 100 to 400， it maintains approximately 86%–87% data reception progress， with an average packet loss rate of approximately 0.2185% in the download scenario. These results demonstrate that the proposed scheme provides a practical balance among post-quantum security， fine-grained authorization， and lightweight vehicular-terminal computation.
