Cryptology ePrint Archive: Report 2020/575

From Rerandomizability to Sequential Aggregation: Efficient Signature Schemes Based on SXDH Assumption

Sanjit Chatterjee and R. Kabaleeshwaran

Abstract: An aggregate signature allows one to generate a short aggregate of signatures from different signers on different messages. A sequential aggregate signature (SeqAS) scheme allows the signers to aggregate their individual signatures in a sequential manner. All existing SeqAS schemes that do not use the random oracle assumption either require a large public key or the security depends upon some non-standard interactive/static assumptions. In this paper, we present an efficient SeqAS scheme with constant-size public key under the SXDH assumption. In the process, we first obtain an optimized (and more efficient) variant of Libert et al's randomizable signature scheme. While both the schemes are more efficient than the currently best ones that rely on some static assumption, they are only slightly costlier than the most efficient ones based on some interactive assumption.

Category / Keywords: cryptographic protocols / Rerandomizable signature, sequential aggregate signature, dual form signature technique, SXDH assumption.

Original Publication (with minor differences): ACISP 2020

Date: received 16 May 2020

Contact author: sanjit at iisc ac in,kabaleeshwar@iisc ac in

Available format(s): PDF | BibTeX Citation

Version: 20200518:070558 (All versions of this report)

Short URL: ia.cr/2020/575


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