Validiums, L2 solutions on Ethereum or not? Vitalik Buterin clarifies

Vitalik Buterin questions the classification of Validiums on Ethereum: are they true layer 2 (L2) solutions or not? The Ethereum co-founder provides clarification, but his comments spark a lively debate within the crypto community.

Ethereum: Validiums are not L2 solutions

Daniel Wang tweeted that an Ethereum rollup is a validium if it uses another data chain for data availability. Ethereum co-founder Vitalik Buterin has confirmed his point. The core of a rollup is unconditional security assurance. This means that you can withdraw your assets even if everyone else is against you. This is impossible if data availability depends on an external system, he explains.

If an Ethereum rollup uses other data chain for DA, it is an Ethereum validium. https://t.co/bFMfUNYlLf

— danielwang.eth🥁 (@daniel_taikoxyz) January 16, 2024

As a reminder, Validium is an Ethereum scaling solution that utilizes zero-knowledge proofs. It allows off-chain transactions while relying on Ethereum’s main network. Unlike zero-knowledge rollups, validium networks do not post transaction data on an L1.

Networks like Celestia utilize a modular blockchain composed of data availability layers and validation layers. That is why they are not rollups but validiums that enable fast and private transactions.

The classification debate persists

In a post on Warpcast, the Ethereum co-founder suggested adjusting certain terminologies to make them simpler. For example, “favoring security” and “favoring scale” to “heavy” vs “light”. However, some disagree with Buterin’s proposals. Ryan Berckmans, a member of the Ethereum community, stated that validiums are L2 networks.

A layer 2 is a chain that sits on top of Ethereum, he stated. He claims to want to continue to debate with anyone who insists that validiums are not Layer 2. The L2Beat platform joins Buterin’s position by stating that validiums and optimiums are not L2s.