Statistically-Secure Bit Commitment and Coin Flipping Protocols Based on Quantum Hardware Assumptions
2026-08-11 • Cryptography and Security
Cryptography and Security
AI summaryⓘ
The authors show that a perfectly secure way to commit to a secret bit is impossible, even with quantum technology. However, they create a new method using hybrid devices called HLPUFs, which mix classical hardware with quantum communication, to achieve a statistically secure bit commitment. Their approach ensures both that the bit stays hidden and that it can't be changed after committing. They also use this idea to build a hardware-based coin-flipping protocol. This work opens a potential path for secure two-party cryptography in quantum networks using special hardware.
bit commitmentquantum cryptographyhybrid locked physical unclonable functionshardware tokensquantum communicationstatistical hidingbinding propertycoin-flipping protocoltwo-party cryptographyquantum networks
Authors
Roo Dunnill, Mina Doosti
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.