Bitcoin’s ‘last resort’ quantum-safe solution just got 79% cheaper: StarkWare
The computational cost for preparing a quantum-resistant Bitcoin transaction, crucial for Bitcoin’s last resort quantum-safe solution, has significantly decreased by approximately 79%, now falling below $67. This reduction follows a week of focused optimization efforts, down from an initial cost of about $320 for the first such mainnet transaction in August, according to StarkWare.
This development is crucial for Bitcoin‘s ‘last resort' quantum-safe solution, making it more practical. The decrease resulted from the Quantum-Safe Bitcoin Optimization Challenge, which identified methods to reduce the GPU computation required for constructing these transactions.
Quantum-Safe Bitcoin (QSB) Design and Implementation
StarkWare researcher Avihu Levy introduced the Quantum-Safe Bitcoin (QSB) design in April. This design outlines a method to incorporate hash-based protection against quantum attacks without modifying Bitcoin's consensus rules. Levy initially characterized it as a “last resort measure” due to its costs, complexity, and limited applicability.
The first QSB transaction was mined and confirmed on August 26, with engineering contributions from Tomer Giladi and submission via MARA’s Slipstream service. This transaction required approximately 3,100 GPU-hours across about 100 GPUs, incurring a compute cost of roughly $320, excluding Bitcoin network fees.
Optimization Challenge and Future Implications
To reduce these substantial costs, StarkWare, Yukon Research, and Eigen Labs initiated the QSB challenge on September 16. This challenge invited developers, researchers, and AI agents to improve the efficiency of the transaction-building software. StarkWare reported 62 accepted improvements across two computational tasks, leading to the estimated 79% reduction in computing cost based on benchmark tests.
This progress occurs amid increasing concerns that advanced quantum computers could compromise Bitcoin's elliptic-curve digital signatures, potentially enabling attackers to steal funds. While QSB offers a protection, StarkWare maintains that a soft fork—a change to Bitcoin's consensus rules—remains a superior long-term solution for comprehensive quantum protection on Bitcoin.