投票的資訊安全在民主社會裡是一重大議題。投票人不會想要讓其他人(包含計票員和其他投票者)知道他所支持的候選人為何。然而，計票員必須要檢視每一張選票的合法性。因此，同時保有投票者隱私以及選票安全將是一個投票系統所會面臨的問題。
過去，人們將選票放入投票箱，直到所有人投票完成才開啟投票箱並統計選票。隨著資訊時代的來臨以及電子投票的方便性不可避免地改變了我們的投票方式。現代電子投票協定是基於計算上的複雜度，例如:RSA。攻擊者無法使用現代電腦來擊破電子投票系統，因為這些投票系統的設計都是基於計算上的複雜度(例如:質因數分解問題、離散對數問題)。
然而，量子電腦的發展使的這些數學難問題可以被有效的解決。1994年，Shor提出了一個可以用來破解現代密碼學演算法。量子平行運算的能力可以減少計算所花費的時間，使得攻擊者得以侵犯他人的隱私以及投票的公平性。
量子密碼學是基於量子力學的特性(例如:海森堡測不準原理、不可複製性)，因此得以提供一個絕對安全的通訊。最近，越來越的研究學者提出多種不同的量子投票協定，顯示量子投票領域是值得探討的議題。

即使過去研究使用絕對安全的密碼學家晚餐問題(dining cryptographers’ problem)來保護投票人的隱私，但這些協定不但沒有防止多重投票與選票竄改，也無法確保選票被正確的統計。
因此，在本篇論文中，我們將會詳細的解釋一個投票系統該達到什麼樣的目標，以及討論和分析前人在過去研究所面臨到的問題。最後，我們將會提出三種不同的協定來解決過去研究所發生的問題，並這三個協定都滿足(1)投票人的隱私(2)選票的安全(3)選票結果的可驗證性(4)選票的合法性。

Secure voting is a crucial issue for a democratic society. A voter does not want other people (tallymen and other voters) to know for whom he or she votes. However, the tallyman must inspect whether the vote is legal. Therefore, maintaining privacy and security is a crucial task.
People have previously deposited their votes into ballot boxes, which are undisclosed until the ballot boxes are opened; however, the current information age and the convenience of electronic voting inevitably have changed voting procedures. Modern e-voting protocols are based on the security of computational complexity, such as RSA. Attackers cannot use classical computers infiltrate e-voting protocols because they rely on computational complexities such as factoring large numbers and solving discrete logarithms.
However, the development of the quantum computer has facilitated solving difficult mathematical problems. The Shor’s algorithm, proposed in 1994, may be used to attack classical cryptography. Quantum parallelism reduces computation time, allowing an attacker to harm the privacy of message owners.
Quantum cryptography based on fundamental quantum-mechanical laws such as the Heisenberg uncertainty principle and the quantum no-cloning theorem, provides unconditional security for communication. Researchers have recently begun using various kinds quantum voting protocols, showing quantum voting to be a considerable problem.
Although unconditional secure solution of the dining cryptographer’s problem has been used to protect voter’s privacy, these protocols cannot prevent duplicate voting and voting modification or guarantee that votes are accurately recorded.
Therefore, this thesis provides an explanation of voting system targets and an analysis of their problem. The 3 proposed protocols provide solutions to this issue and satisfy the desirable features of privacy, security, verifiability, and eligibility.

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