數位簽章在數位通訊中確保真實性與完整性方面扮演著關鍵角色。然而，傳統的數位簽章方案依賴於公鑰基礎設施（PKI），而這種基礎設施可能複雜且難以在大規模環境中管理。身份基礎簽章（IBS）方案簡化了金鑰管理，因為它允許以任意識別碼作為公鑰，消除了對數位憑證的需求。儘管如此，IBS 方案仍存在金鑰託管問題，因為私鑰是由中央機構簽發，這帶來了偽造與金鑰洩漏的風險。為了解決這個問題，我們提出了一種新穎的註冊基礎簽章方案，其中用戶可以獨立產生自己的金鑰對，並將公鑰註冊到公共公告板上。我們的設計採用向量承諾，以實現註冊與簽章有效性的高效且非互動式驗證。這種方法消除了金鑰託管風險，同時保留了身份基礎密碼學的簡單性與實用性，使其更適合去中心化及大規模應用。

Digital signatures are essential for ensuring authenticity and integrity in digital communications. However, traditional schemes rely on public key infrastructures, which can be complex and difficult to manage at scale. Identity-based signature (IBS) schemes simplify key management by allowing arbitrary identifiers to serve as public keys, removing the need for digital certificates. Despite this advantage, IBS schemes suffer from the key escrow problem, as private keys are issued by a central authority, introducing risks of forgery and key compromise. To address this issue, we propose a novel registration-based signature scheme in which users independently generate their own key pairs and register their public keys on a public bulletin board. Our design uses vector commitments to allow efficient and non-interactive verification of registration and signature validity. This approach eliminates the key escrow risk while preserving the simplicity and practicality of identity-based cryptography, making it more suitable for decentralized and large-scale applications.

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