Vitalik Buterin says Ethereum can handle temporary loss of finality

Ethereum co-founder Vitalik Buterin asserted that the network can afford to lose finality occasionally, even after a recent client bug nearly disrupted its confirmation mechanism. He clarified that while finality means the network is "really sure" a block won't revert, a temporary delay of hours due to a major bug is acceptable, emphasizing that the critical issue to avoid is "finalizing the wrong thing."

Protocol expert Fabrizio Romano Genovese agreed, noting that when finality is lost, Ethereum temporarily operates more like Bitcoin, whose finality is probabilistic. Ethereum's deterministic finality is achieved when a block receives over 66% validator votes to become "justified," and then passes two epochs (64 blocks) without further issue. Incidents causing finality loss do not compromise security but revert guarantees to probabilistic.

However, Genovese pointed out that infrastructure relying on finality, such as some Layer-2 (L2) bridges, would be affected. Polygon confirmed that while deposits to its sidechain might be delayed waiting for finality, users would not experience rollbacks or message invalidation; the practical impact is just longer deposit times. Genovese concluded that delays are ultimately the choice of bridge developers who choose not to implement fallback mechanisms.

(Source：Cointelegraph)