Quantum-Enabled Discrete Distribution Sampling for Post-Quantum
Lattice-Based Cryptography
Abstract
Lattice-based cryptography is considered the most promising candidate
for post-quantum public key cryptography such as key encapsulation and
digital signature schemes. Accurate and efficient sampling of matrix /
vector elements and polynomial coefficients from specified discrete
probability distributions is crucial to the security and efficiency of
lattice-based cryptography protocols. In this work, a design methodology
is proposed to implement these sampling operations using currently
available quantum computing hardware. Quantum circuits for sampling from
uniform, trinary, binomial and discrete Gaussian distributions are
presented. Implementation results obtained from simulation as well as
measured from real cloud-based quantum hardware are also presented and
analyzed. Although the proposed circuits require only few qubits, they
implement practical distribution parameters used by various
lattice-based protocols. This clearly demonstrates the immediate
relevance of such quantum circuits in the context of currently available
small-scale quantum computers, and they have the potential to enhance
post-quantum cryptography implementations on quantum-enabled cloud
environments.