Committing to quantum resistance: a slow defence for Bitcoin against a fast quantum computing attack

Area of Science:

• Cryptography
• Quantum Computing
• Blockchain Technology

Background:

• Quantum computers pose a significant threat to current public key cryptography.
• Bitcoin's security relies on the Elliptic Curve Digital Signature Algorithm (ECDSA), vulnerable to quantum attacks.
• Existing Bitcoin protocols lack inherent quantum resistance.

Purpose of the Study:

• To assess the specific threats quantum computers present to Bitcoin transactions.
• To propose a protocol for migrating Bitcoin funds to quantum-resistant signatures.
• To ensure Bitcoin's security against future quantum-capable adversaries.

Main Methods:

• Analyzing the impact of quantum algorithms on ECDSA.
• Designing a commit-delay-reveal protocol for secure fund migration.
• Evaluating the protocol's functionality even if ECDSA is compromised.
• Proposing a soft fork implementation for Bitcoin protocol modification.

Main Results:

• Identified specific vulnerabilities of ECDSA to quantum attacks within the Bitcoin network.
• Developed a functional commit-delay-reveal protocol for transitioning to quantum-resistant digital signatures.
• Demonstrated the protocol's resilience, operating effectively even with a compromised ECDSA.
• Outlined a feasible soft fork mechanism for integrating the proposed security enhancements into Bitcoin.

Conclusions:

• Quantum computing necessitates a transition to quantum-resistant cryptography in Bitcoin.
• The proposed commit-delay-reveal protocol offers a viable solution for secure fund migration.
• Soft fork implementation allows for gradual adoption of quantum-resistant measures without disrupting the network.
• Proactive security measures are crucial for maintaining the integrity of cryptocurrencies in the quantum era.