Elena Bakos Lang

In August 2023, Meta engaged NCC Group’s Cryptography Services practice to perform an implementation review of their Auditable Key Directory (AKD) library, which provides an append-only directory of public keys mapped to user accounts and a framework for efficient cryptographic validation of this directory by an auditor. The library is…

Introduction This two-part blog series aims to build some intuition for the main techniques that are used to construct lattice-based signatures, focusing in particular on the techniques underlying Falcon and Dilithium, the two lattice-based signature schemes selected for standardization by the National Institute of Standards and Technology (NIST). In part…

Introduction Since the first lattice-based cryptography results in [Ajtai96], lattices have become a central building block in quantum-resistant cryptosystems. Based on solving systems of linear equations, lattice-based cryptography adds size constraints or error terms to linear systems of equations, turning them into quantum-computer resistant one-way or trapdoor functions. Since the…