Ethereum developer Julian (@_julianma) has introduced the Fast Confirmation Rule (FCR), a new mechanism designed to slash bridging times from Ethereum’s Layer 1 to Layer 2 networks and centralized exchanges. The rule promises confirmations in about 13 seconds, compared to the minutes users currently wait when using canonical bridges.
How FCR Changes Bridging
The Fast Confirmation Rule reduces deposit times by 80–98% for most L2s and exchanges. Instead of waiting for multiple blocks, FCR relies on counting attestations to determine fork‑choice weight. Once a block is dominant, nodes run robustness checks to confirm security. Importantly, this rollout requires no hard fork — as soon as a client implements FCR, nodes can run it automatically.
The benefits are broad:
- Exchanges: Deposits from Ethereum to centralized platforms drop to ~13 seconds, improving off‑ramps and user experience.
- L2s: Faster deposits mean less capital locked in bridging, lower costs, and more efficient blob fee markets.
- Bridges & Solvers: Assets move faster with provable security, reducing reliance on heuristics.
- RPCs: Better‑connected RPCs can offer faster confirmations, creating new value propositions.
Security Assumptions and Adoption
FCR assumes synchrony in the network (attestations delivered within ~8 seconds) and that no adversary controls more than 25% of the stake. If these assumptions fail, FCR falls back to slower confirmation or finality, ensuring safety. With Ethereum’s stake valued at over $22 billion, the threshold is considered secure for large transfers.
Consensus client teams are already implementing FCR, and exchanges, L2s, and solvers can adopt it with minimal changes. By repurposing the existing safe block tag in JSON‑RPC, FCR integrates seamlessly into the current infrastructure. If widely adopted, it could become the new industry standard for Ethereum confirmations.
