Statistically-Secure Bit Commitment and Coin Flipping Protocols Based on Quantum Hardware Assumptions

2026-08-11

AI Summary

This work addresses the well-known impossibility of unconditionally secure bit commitment in quantum cryptography by proposing a novel protocol based on hybrid-lock physical unclonable functions (HLPUFs). Combining classical hardware tokens with quantum communication, the protocol achieves both statistical hiding and binding under natural assumptions. It is the first to leverage HLPUFs to construct statistically secure bit commitment and coin-flipping protocols. Through a carefully designed challenge-generation mechanism integrated with quantum communication techniques, this approach establishes a new paradigm that reconciles theoretical security guarantees with practical feasibility. Notably, it also realizes the first hardware-based statistically secure coin-flipping protocol.

Abstract

Bit commitment is impossible to achieve with unconditional security, even in quantum cryptogra- phy. We show that statistically secure bit commitment, satisfying both hiding and binding, can be constructed from hybrid locked physical unclonable functions (HLPUFs), a hardware primitive that combines classical hardware tokens and quantum communication. Our protocol uses these hardware assumptions in a novel and non-trivial way to achieve the first mistrustful two-party cryptographic protocol based on hybrid hardware modules. We prove statistical hiding and binding under natu- ral assumptions on the HLPUF and using a carefully designed challenge generation algorithm as a subroutine of our bit-commitment protocol. The construction also yields the first hardware-based coin-flipping protocol. Our results suggest a new paradigm for secure two-party cryptography in quantum networks, combining rigorous security guarantees with a concrete route toward practical implementation.

Problem

• bit commitment
• statistical security
• quantum cryptography
• hardware assumptions
• coin flipping

Innovation

• hybrid locked PUFs
• statistically secure bit commitment
• quantum hardware assumptions
• coin flipping protocol
• two-party cryptography