收集和分析所有者的資料成為許多雲服務的關鍵業務，因此和同意授權的資料所有者進行適當的資料共享成為必然的趨勢。然而，傳統的通過中心化資料託管伺服器的資料共享方法可能會犧牲所有者的資料隱私且資料安全性較弱。主要是託管中心實際將所有資料存在自己的伺服器上，而原始資料的所有者只剩下虛擬的資料所有權，失去了對資料確實訪問控制權。因此，基於伺服器「誠實但好奇」的不可信假設，我們提出了一種基於3層 SSE-ABE-AES (3LSAA) 密碼學的隱私保護資料共享協議。即使託管中心不可信，3LSAA協議讓所有者實現了對託管中心資料自動訪問控制管理和方便的文件搜索。除了實現資料自主權外，我們的方法還提高了系統可用性，消除了傳統SSE和ABE方法的缺陷，並為用戶的可用性提供了本地AES密鑰恢復方法。

As data collection and analysis become critical functions for many cloud applications, proper data sharing with approved parties is required. However, the traditional data sharing scheme through centralized data escrow servers may sacrifice owners' privacy and is weak in security. Mainly, the servers physically own all data while the original data owners have only virtual ownership and lose actual access control. Therefore, we propose a 3-layer SSE-ABE-AES (3LSAA) cryptography-based privacy-protected data-sharing protocol based on the assumption that servers are honest-but-curious. The 3LSAA protocol realizes automatic access control management and convenient file search even if the server is not trustable. Besides achieving data self-sovereignty, our approach also improves system usability, eliminates the defects in the traditional SSE and ABE approaches, and provides a local AES key recovery method for user’s availability.

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