近年來，隨著網路與智慧型裝置的普及，人們對跨裝置的雲端硬碟服務需
求增加，其甚至取代了傳統電腦，成了個人資料儲存的重要存在。雲端硬碟服
務使得人們可以隨時隨地透過網路存取檔案，雲端硬碟帶來的方便性深深地改
變人們的行為。然而，在眾多的雲端硬碟服務中，不同廠商的服務都有其特別
的限制，例如限制上傳檔案大小、有限的免費空間、檔案需要公開或用戶端必
須透過提供商的應用程式管理檔案等等，多種限制造成了使用者的不便。而最
令人詬病的缺點為提供商可能在雲端中心備份了多份你的檔案，即使透過刪除
功能也無法確信其在雲端已完全抹除檔案，檔案的隱密性受到懷疑。
為了解決這些問題，我們提出一整合多個雲端空間的架構讓使用者可以透
過單一窗口管理多個雲端硬碟。在此架構中，檔案儲存在本地端的檔案系統中，
而雲端上的檔案儲存在多個雲端空間中，彷彿每個雲端空間串聯在一起，使用
者可以隨著自己的需求增加或刪除儲存空間。最後使用者可以無縫加密雲端上
的檔案，即使檔案遭到備份也無法閱讀加密後的內容。此架構需要伺服端管理
用戶檔案與實現同步功能，此篇論文中將詳細描述如何實現此架構的伺服器端，
包括與用戶端的傳輸協議、應用程式介面[1] 設計、資料庫設計、程式核心等，
此伺服端將兼具服務導向特性，能夠在錯雜的環境中提供良好的溝通介面，並
且在未來環境變化時也能快速反應。

In recent years, smart phones and wireless networks became more widespread
and the demand for cloud storage services is strong. Cloud storage services gradually
replace the hard drives in traditional personal computers and become a new
storage media of user’s data. With cloud storage services, people can access their
data at any place and at any time as long as network access is available. This
convenience has fundamentally changed our daily lives. However, the existing
commercial cloud storage services do impose inconveniences and limitations. For
instances, service providers may put a limit on the uploading file sizes, or a limit
on the storage space. As another example, nearly all services require users to manage
their data using software released by the providers. Invariably, these software
limit the users to only one cloud storage account, which severely limits the storage
space. Another great concern of using commercial cloud storage services is that
service providers always keep backups for the sake of reliability. Even after users
have deleted their data, there is no guarantee that all corresponding backups are
deleted by the service providers. This causes a great concern in data security.
We propose an architecture for integration of multiple cloud storage services to solve
the problems above. In this architecture, files are stored in file trees locally. Remotely,
files are stored in multiple cloud storage services such that all storage limits are
not violated. Users can add more cloud storage if more space is desired. In
addition, user’s data are encrypted before they are stored in the cloud. This
architecture requires a server to manage user’s accounts and to handle file synchronization.
In this thesis, we address the design issues and the implementation
of a service-oriented server .

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