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 proposal involves waiting for an attacker to demonstrate their capabilities and then reacting accordingly. This 'wait and react' strategy relies on a 'canary' system, which would trigger a network-wide restriction on older bitcoin wallets only if a quantum-capable attacker successfully unlocks a specially designated address. The address would contain a small amount of bitcoin, and any spend from it would serve as public proof of the quantum threat, automatically triggering the network-wide freeze. The proposal also includes a bounty system, where users can contribute bitcoin to the address, rewarding the first entity to demonstrate a quantum attack publicly. This approach is designed to provide an alternative to the controversial BIP-361 proposal, which would impose a fixed five-year timeline for phasing out vulnerable addresses, regardless of whether quantum computers are capable of attacking the blockchain. Critics of BIP-361 argue that it undermines Bitcoin's core principle of private key holder control, and could result in the permanent freezing of unmigrated coins. The 'wait and react' strategy, on the other hand, aims to minimize disruption to users while still providing a robust defense against quantum threats. 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, which may not be a reliable bet.