根據先前的研究，在論文「基於區塊鏈的對稱式金鑰直接式數位簽章及其應用」中 [33]，簽名者用對稱式金鑰加密產生簽章，將訊息、簽章和金鑰放入區塊鏈，讓接收者可以在區塊鏈上公開驗證簽章。本論文將其簽章和驗證流程進行改良，讓整體效能及安全性提升。提出一種基於區塊鏈的金鑰雜湊數位簽章協定。類似於非對稱式金鑰數位簽章協定，用對稱的金鑰搭配雜湊函數，也就是金鑰雜湊訊息鑑別碼的概念，來進行簽名，產生出的簽章可以公開給他人驗證，再加上運用區塊鏈技術，攻擊者不能使用已公開的資訊 (如：金鑰或訊息) 進行竄改或偽造簽章。提出的協定滿足數位簽章協定的安全要求 (身分驗證、完整性及不可否認性)，也提供不可偽造性、匿名性、前向安全和抗量子特性。另外，提出的協定不需要可信任的第三方為使用者身分註冊。

In Yeh’s thesis, “Blockchain-based Symmetric-key Direct Digital Signature Scheme and Its Application” [33], the signer generates a signature encrypted by the symmetric-key algorithm and places the message, signature, and key into the blockchain. Receiver verify the signature publicly in the blockchain. This thesis improves on Yeh’s signature phase and verification phase to increase the performance and security.
We propose a keyed-hash digital signature scheme for blockchain which uses the symmetric key and the hash function called the keyed-hash message authentication code to generate the signature which can be verified by others publicly. Additionally, the proposed scheme uses blockchain such that the attacker cannot make use of published information such as keys or messages to manipulate or forge signatures.
The proposed scheme not only satisfies the security requirements of digital signatures, including authentication, integrity and non-repudiation, but also provides unforgeability, anonymity, forward secrecy and quantum resistance. Additionally, the proposed scheme does not need any trusted third party to register user identities.

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