Bitcoin Developers Propose 'Wait and React' Strategy to Counter Quantum Computing Threats

The Bitcoin community is considering a novel approach to addressing the potential threat of quantum computing to the network's security. Instead of imposing a pre-scheduled freeze on vulnerable coins, the proposed 'canary' system would only trigger a network-wide restriction if a quantum-capable attacker demonstrates their capabilities on-chain. This approach is based on the assumption that the first entity to demonstrate a quantum attack would claim a bounty rather than attempting to steal vulnerable coins. The system works by placing a small amount of bitcoin in a special address that can only be unlocked by a quantum-capable attacker, with any spend from that address serving as public proof that the threat has arrived and triggering a network-wide freeze. The proposal is designed as an alternative to BIP-361, which would impose restrictions on a fixed five-year timeline regardless of whether quantum computers are actually capable of attacking Bitcoin's blockchain. Critics of BIP-361 have argued that it undermines Bitcoin's core principle of control resting solely with private key holders. The 'canary' system introduces a financial incentive, allowing users to contribute bitcoin to the address and create a bounty that rewards the first entity to demonstrate a quantum attack publicly. The proposal also includes a 'safety window' designed to make stealth attacks harder, during which vulnerable coins could still move but the recipient would be unable to spend them for an extended period. However, the success of this approach relies on the assumption that the first entity capable of breaking Bitcoin would claim the bounty rather than attempting to steal millions of bitcoin, which is a bet that cuts against the network's design principles and historical risk management strategies.