Bitcoin Developers Propose Alternative to Pre-Scheduled Freeze in Response to Quantum Computing Threat

The Bitcoin community is considering a novel approach to address the potential threat of quantum computing to the network's security. Instead of imposing a pre-scheduled freeze on vulnerable coins, the new proposal involves a 'canary' system that would trigger a network-wide restriction only if a quantum-capable attacker demonstrates their capability. This approach is designed to replace earlier plans to impose a fixed timeline for freezing older bitcoin wallets. At the heart of the proposal is a 'wait and react' strategy, which relies on placing a small number of bitcoin into a special address that can only be unlocked by a quantum-capable attacker. If the attacker spends from that address, it would serve as public proof that the threat has arrived, automatically triggering a network-wide freeze of older wallets. The proposal also includes 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. This approach is seen as an alternative to BIP-361, a controversial proposal that 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 private key control and could lead to the permanent freezing of unmigrated coins. The new proposal aims to address these concerns while minimizing the risk of disrupting users prematurely. However, it relies on the assumption that the first entity capable of breaking Bitcoin would claim the bounty rather than executing a large-scale theft. This assumption has raised concerns, as it goes against the worst-case scenario that Bitcoin's design has always tried to prevent. If the assumption proves incorrect, Bitcoin may face the worst of both worlds: the catastrophe it was trying to prevent, and the realization that a fixed-timeline defense would have stopped it.