無線感測網路如今已經廣泛的被應用在各種領域，然而無線感測節點的運算能力、記憶空間以及能源等都是有限的。此外，由於無線感測節點在資料傳輸所消耗的能源遠大於計算所消耗的部份，因此為了減少能源的消耗，無線感測節點常以計算來取代傳輸，而透過資料的整合則能達到減少傳輸量，但資料整合常帶來一些副作用以及遭受一些攻擊。
首先，資料整合是透過利用較少的資料量去表示大量的資料內容，因此經過整合的資料僅能表現出一些結果，而無法得知原始資料的相關特性，例如無法藉由運算的最終結果來得知原始資料的分布情況。換言之，使用者無法透過已經整合的資料還原原始資料，而進行更進ㄧ步的分析。
無線感測網路中的中間節點能夠在他們進行資料整合之時針對傳輸的資料進行竄改或者丟棄。這些遭受竄改或丟棄的資料可能導致最終結果的偏差，進而導致使用者做出錯誤的決定。因此保護資料避免攻擊者的篡改是一件非常重要的事。然而，大部分的資料整合協定無法同時達成資料篡改以及丟棄等攻擊的偵測或抵擋。
本篇提出一種輕量安全的資料整合協定以解決以上所提到的問題，同時也提出了詳細的安全性分析以驗證本篇架構的安全，最終並依據安全性、記憶空間量、計算量、通訊量以及應用環境將本篇架構與之前其他的方法進行比較。

Wireless sensor networks are widely utilized in many areas nowadays. Sensor nodes have limited computation ability, memory and energy and so on. In addition, the energy consumption of communication is much more than computation for wireless sensor nodes. For the reason, data aggregation is a widely used technique in wireless sensor networks to reduce communication cost. Nevertheless, data aggregation brings some side effects and suffers from some attacks.
Firstly, data aggregation exploits fewer messages to represent a great deal sensing readings. Therefore, the aggregated values just present some results. Nevertheless, the base station is unable to be aware of the distribution of these original sensing values. In other words, the base station can not recover to original messages from aggregated value to perform further analysis.
Secondly, in wireless sensor networks, internal nodes are able to alter messages when it aggregates receiving messages. The altered messages will result in a deviation of final result. Consequently, the false result could cause a wrong decision. Hence, it is significant to protect these messages from an attacker altering them when internal nodes aggregate these data. However, less of them can indeed guarantee data integrity and resist dropping attack and so on. An attacker can simply forge data to affect the decision of base station by compromised nodes.
This thesis, therefore, proposes a lightweight secure data aggregation protocol to solve above side effects and attack models. In the meanwhile, this thesis also provides detailed security analyses to verify the security of our scheme. Finally, we compare our scheme with other precious methods in terms of security, memory cost, communication cost, computation cost, and application environment etc.

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