ACISP 2024: Best Paper Award
Pairing-Free ID-Based Signatures as Secure as Discrete Logarithm in AGM
Best Paper Award — Australasian Conference on Information Security and Privacy (ACISP 2024)
Identity-based signatures (IBS) allow a signer’s identity — such as an email address — to serve directly as the public key, removing the need for certificate management. This paper presents a new pairing-free IBS scheme with tight EUF-CMA security under the discrete logarithm (DL) assumption in the Algebraic Group Model (AGM). The key contribution is an OR-proof technique that embeds the DL problem instance into the user’s private key construction, enabling tight security against chosen identity-and-message attacks — a challenge that prior techniques could not resolve. The scheme is lightweight, requiring no expensive pairing operations.
