PANews reported on August 7th that Vitalik Buterin, in a post on the X platform, expressed surprise at the fact that so many mainstream Layer-2 platforms are at the first stage of security standards. The next goal should be to achieve fast withdrawal times (less than an hour) through a ZK (also known as zero-knowledge proof) system. This is more important than the second stage. If native withdrawal times can be reduced to under an hour in the short term and to 12 seconds in the medium term, Ethereum Layer-1 will further solidify its position as the default platform for issuing assets and the economic center of the Ethereum ecosystem. To achieve this, OP proof systems must be abandoned, as they inherently require a multi-day wait for withdrawals.

Historically, zero-knowledge proof technology has been immature and expensive, making OP proofs a sensible and secure option. However, this situation is rapidly changing. Earlier this year, Vitalik proposed a "2-of-3" ZK + OP + TEE proof system strategy that strikes a balance between security, speed, and maturity.

• 2-of-3 systems (ZK, OP) are trustless, so no single actor (including the TEE manufacturer or a side-channel attacker) can break the proof system by violating the trust assumption.
• The 2-of-3 system (ZK, TEE) is instant, so withdrawals are fast under normal circumstances.
• 2-of-3 systems (TEE, OP) have been in production for many years in various environments.

This is just one approach; perhaps people will choose a ZK + ZK + OP tiebreaker, or a ZK + ZK + security committee tiebreaker. I don't have a strong opinion on either; I care about the fundamental goals: speed (under normal circumstances) and security. With such a proof system, the only bottleneck for fast settlement becomes the gas cost of submitting proofs on-chain.