StarkWare Achieves Quantum-Resistant Bitcoin Transaction
StarkWare has announced a significant milestone in cryptocurrency security: a researcher named Avihu Levy successfully executed a quantum-resistant Bitcoin transaction on the main network. This groundbreaking transaction, which utilized a 10,000-satoshi output, was recorded in block 964,199, marking a first for this innovative approach without deviating from Bitcoin’s consensus rules.
Interestingly, the transaction was mined by MARA Pool, which utilized its Slipstream service to directly receive the transaction, as it was classified in a nonstandard format that standard nodes were unable to relay through the public mempool.
Details of the Quantum-Safe Bitcoin (QSB) Initiative
Nathan Jeffay, a spokesperson for StarkWare, detailed that the computational costs for this unique transaction ranged between $150 and $200, and the overall process required several hours to complete. This serves as a proof of concept that demonstrates the feasibility of providing additional security for individual outputs under current Bitcoin regulations, albeit at a significant operational cost.
Levy’s scheme, dubbed Quantum-Safe Bitcoin (QSB), was initially proposed in April. It integrates hash-based one-time signatures with computational search techniques that bind authorization to specific transactions, thereby thwarting forgery. This initiative is particularly relevant given recent research by Google, which suggested that a sufficiently powerful quantum computer could derive a Bitcoin private key within a mere nine to twelve minutes of a public key becoming available. Such a capability could potentially allow an attacker to rewrite pending transactions during the confirmation phase.
The cost for creating a QSB transaction was estimated to be between $75 and $150 using GPU resources, while StarkWare’s current execution of the transaction reflected costs of around $150 to $200. Unlike network-wide cryptographic enhancements, QSB is designed for individual transactions, permitting the movement of coins into more secure outputs without necessitating a complete overhaul of the Bitcoin protocol. However, it should be noted that it does not safeguard coins whose public keys have been exposed prior to their transfer.
Challenges and Future Implications
The atypical classification of the transaction presented a practical challenge within Bitcoin Core’s default relay policy, which prevents standard nodes from relaying it prior to being confirmed. Thus, it required direct submission to a compliant miner via services like MARA’s Slipstream, highlighting the need for compatible transaction preparation and direct access to miners.
Eli Ben-Sasson, the CEO of StarkWare, emphasized that QSB aims to provide immediate protection while more advanced protocol-level safeguards are formulated. This experiment illustrates a workaround within existing regulations, rather than attempting to redefine the foundational cryptography governing the network.
In the broader context of Bitcoin development, there are parallel discussions about potential upgrades, including BIP-360, which proposes a soft fork introducing a new output type designed to be more resilient to quantum threats while retiring aspects of Taproot that are vulnerable to quantum attacks. However, QSB operates independently of any proposed protocol changes, demonstrating that Bitcoin’s current consensus rules can adapt to support at least one form of quantum-resistant transactions as the cryptocurrency community continues to explore enhanced protective measures.
