Talk starts at 2 PM
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Title: Commitment Schemes Based on Module-LIP
Abstract: Commitment schemes are fundamental cryptographic primitives that allow one party to hide a message while remaining bound to it. Recently, Jiang et al. showed that such schemes can be built from group actions, and gave an instantiation based on the Lattice Isomorphism Problem (LIP) and the Lattice Automorphism Problem (LAP). This opened a new way of using LIP beyond its more familiar applications in signatures and encryption.
This talk presents the paper Commitment Schemes Based on Module-LIP, which asks whether the LIP-based commitment framework can be made more efficient by moving from ordinary lattices to module lattices. Module lattices are central in schemes such as HAWK and often provide better asymptotic efficiency, but they also introduce new algebraic constraints. In particular, the direct choices of acting groups either make re-randomization difficult or destroy the determinant information needed for the extractor.
The talk will explain the plain LIP commitment picture first, then discuss the module construction, and the hardness connections to module-LIP and module-LAP.
