雲端服務是近年各企業相當重視的資訊系統應用，現今的網路環境，為了更方便、快速分享佈署資料、應用服務和同時兼顧儲存成本和提升效率，從個人到企業逐漸選擇把資料移往雲端存放，利用雲端服務協助完成工作。現在一般使用者在操作電腦時，大多數會額外安裝防毒軟體和防火牆，原因是使用者已經了解到保護資料對個人隱私的重要，同樣當把資料上傳至雲端後，因資料不再受到使用者的管控，而是由雲端平台服務商全權管理，對安全的顧慮更加提高，系統服務商該如何保護客戶的資料完整、隱私和可用性，是每位雲端服務使用者最重視的部分。
本研究將透過兩種公有雲資料庫保護方式：CryptDB與Fragmentation，探討企業如何在雲端環境保護委外資料的運作，同時能符合機密、完整、可用性的資安三要條件，以及在儲存管理、數據操作、使用流程上的差異比較，給予建置資料庫時的建議與選擇判斷，藉此提供具體貢獻。

During the past few years, cloud service is an information system application that enterprises pay great attention to. In today's network environment, to make it easier and faster to share deployed data, application services, and to balance storage costs and efficiency, individuals and businesses are choosing to move data to the cloud and use cloud services to help you get the job done. Store and use the cloud service to assist with the work. Nowadays, the general public use computers and most of them will install anti-virus software and firewalls. The reason is that users have learned that protecting data is important to personal privacy. Similarly, when data is uploaded to the cloud, data is no longer controlled by users. It is managed by the cloud platform service provider and the security concerns are further enhanced. How the system service provider can protect the customer's data integrity, privacy and availability is the most important part of every cloud service user.
In this study will use two public cloud database protection methods: CryptDB and Fragmentation to explore how companies can operate outsourced data in the cloud while meeting the three essential conditions of confidentiality, integrity, and availability, as well as the comparison of differences in storage management, data operation, and usage processes. Give specific contributions by giving advice and choice to build a database.

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