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-emptive freeze on vulnerable coins, the proposed 'canary' system would only trigger a network-wide restriction if a quantum-capable attacker demonstrates their capability on-chain. This 'wait and react' strategy is designed to minimize disruption to users while still providing a defense against potential quantum attacks. 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. A bounty would be offered to the first entity to demonstrate a quantum attack, providing a financial incentive for them to reveal their capability rather than exploiting it for malicious purposes. However, this approach relies on the assumption that the first entity capable of breaking Bitcoin's security would claim the bounty rather than executing a large-scale theft. This assumption has raised concerns among some members of the Bitcoin community, who argue that it goes against the network's core principle of prioritizing security and decentralization. The proposal is seen as an alternative to BIP-361, a controversial proposal that would impose a fixed five-year timeline for phasing out vulnerable addresses and invalidating old signature schemes. Critics of BIP-361 have argued that it could lead to an 'authoritarian and confiscatory' outcome, undermining the principles of decentralization and user control that underpin the Bitcoin network. The 'canary' system, on the other hand, is designed to provide a more flexible and adaptive approach to addressing the quantum computing threat, while also minimizing the risk of disruption to users. However, its success relies on the willingness of potential attackers to reveal their capability and claim the bounty, rather than exploiting it for malicious purposes.