Cryptology ePrint Archive: Report 2021/1575

Shorter Lattice-Based Group Signatures via Almost Free'' Encryption and Other Optimizations

Vadim Lyubashevsky and Ngoc Khanh Nguyen and Maxime Plancon and Gregor Seiler

Abstract: We present an improved lattice-based group signature scheme whose parameter sizes and running times are independent of the group size. The signature length in our scheme is around $200$KB, which is approximately a $3$X reduction over the previously most compact such scheme, based on any quantum-safe assumption, of del Pino et al. (ACM CCS 2018). The improvement comes via several optimizations of some basic cryptographic components that make up group signature schemes, and we think that they will find other applications in privacy-based lattice cryptography.

Category / Keywords: public-key cryptography / group signatures, lattices

Original Publication (with major differences): IACR-ASIACRYPT-2021
DOI:
10.1007/978-3-030-92068-5_8