7. 全同態加密之應用
7.3 相等性驗證之應用
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7.3 相等性驗證之應用
相等性驗證所能推廣出來的應用相當廣泛，例如線上拍賣競標，線上商業談判，電 子投票，雲端資料庫計算，線上登入…等，都是可以利用此類技術加以解決，尤其是現 在資料庫系統的普及，使得儲存資料以及對資料進行分析已經是商業上面不可或缺的分 析工具時，我們應該對這些重要資料的安全風險更加謹慎，例如就商業面而言，我們可 以得知該項產品最終的總銷售數量，但卻無法得知該產品各月份的銷售量，這些對企業 來說，或許就是他們想要隱藏的秘密資訊，或是企業併購時，我們只可得知雙方對於此 併購金額上的共識相不相同，但是卻無法得知雙方希望買下或是賣出的金額。而我們在 7.1 以及 7.2 所提出的相等性驗證皆可以運用在以上我們所提供的應用上，並且讓其具 可行性且易於實行。
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8. 結論及未來展望
本研究最大的貢獻，是在於我們改良 Gentry 的全同態加密方案。讓加密所需要的公 鑰並不需要佔據太多的硬體空間或是資源，利用減少公鑰個數來達到降低所需空間，並 再資料隱私的情況下，同樣的進行對資料加密以及同態運算的正確性，並且與 Gentry 的全同態相比，我們降低公鑰所需空間使其易於實作，並且在安全性以及正確性上並不 會造成任何影響使其依舊保有其隱私性、正確性、安全性三項特點。
在未來，我們會針對所選取的集合 S 大小對應公鑰的數量來進行進一步的研究。雖然增 加集合 S 會使降低的公鑰數量更為明顯，但是在正確性以及安全性來說，可能會造成疑 慮。因此如何在兩端之間求出最佳的平衡數量是我們未來所要進一步研究的課題。
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