Canonical Liftings for Group Actions

Abstract

Canonical liftings were introduced in a recent pre-print as a means to compress group-action-based sigma protocols. They generalise existing techniques, such as the canonical forms used in LESS, and thus are inherently a compression argument; however, under some hypotheses, they preserve the hardness of the underlying group-action.

We show how they can be used to produce a (linkable) ring signature, instantiated on linear code equivalence as CE(Le)ReS. Can they construct other primitives, such as blind signatures? What happens if we instantiate them on, e.g., the group actions underlying lattices and isogenies?

Notes

This talk was first held at ALPEC summer school, Trento.

Material

• slides for ALPEC
• article