現今大部分的密碼系統之安全性皆植基於一些數學計算難題上，使得無法在多項式時間複雜度內破解問題，例如因數分解問題與離散對數問題，然而，一般相信利用量子電腦可以有效率地破解這些難題，因此，如何結合量子的物理特性與傳統密碼技術來發展量子協定以達到無條件安全為重要議題。

一般資料在網路間傳遞時，必須保護資料的安全與秘密，而使用者雙方必須先協商出共享金鑰，利用金鑰對傳輸資料加密，預防機密洩漏。因此，已有許多文獻提出各式各樣的量子金鑰分配協定，利用量子傳送金鑰，並結合傳統密碼技術以確認金鑰完整性。

目前量子金鑰分配系統中尚未提出一套正規化的安全證明，有鑑於此，本論文試圖提出一套適用於量子金鑰分配協定之證明模組，並以現有數個金鑰分配協定為例，如BB84、B92、EPR等，證明其金鑰之安全性。

此外，本論文應用傳統密碼技術中雜湊鏈之特性，提出一100%量子利用率、減少傳統通道的輸出量以及降低生產量子成本之金鑰分配協定，並以上述之證明模組討論其金鑰安全性。

Most classical cryptosystems base their security on mathematical computational problems which cannot be solved in polynomial time complexity, e.g., large number factorization and discrete logarithm problems. However, it is believed that these mathematical problems can be solved efficiently by quantum computers. Therefore, how to use the properties of quantum physics to develop quantum protocols that achieve unconditional security is a very important security issue.

In general, when data is transmitted via internet, its security should be guaranteed. Commonly the sender and the receiver have to negotiate a session key with each other to encrypt transmitted data. Many variants of quantum key distribution protocols had been proposed in the literature. They use the quantum bits to transmit keys and sometimes combine classical cryptography to confirm the integrity of keys.
However, how to formally prove the security of a proposed quantum key distribution (QKD) is still remained open. Therefore, this thesis first tries to propose a security proof model based on sequences of games to prove the security of a QKD, such as BB84, B92, EPR and etc.

In addition, a new quantum key distribution protocol which combines the classical cryptography technique, a hash chain, with quantum bit distribution has also been proposed. The newly protocol can achieve 100% quantum key efficiency and reduce communication cost of classical channels as well as the cost of quantum bits generating.

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