A note on quantum safe symmetric key growing

TL;DR

This paper discusses a quantum-safe method for growing symmetric keys using pre-shared secrets and randomness beacons, which is not fully information-theoretically secure but offers practical quantum resistance.

Contribution

It introduces a novel approach combining pre-shared secrets and randomness beacons for quantum-safe key growing, expanding the scope of quantum-resistant cryptographic protocols.

Findings

Key growing can be achieved with pre-shared secrets and randomness beacons.

The method is not fully information-theoretically secure but remains quantum safe.

Practical implications for quantum-resistant cryptography are discussed.

Abstract

Quantum key distribution is a cryptographic primitive for the distribution of symmetric encryption keys between two parties that possess a pre-shared secret. Since the pre-shared secret is a requirement, quantum key distribution may be viewed as a key growing protocol. We note that the use of pre-shared secrets coupled with access to randomness beacons may enable key growing which, though not secure from an information-theoretic standpoint, remains quantum safe.