Ethereum co-founder Vitalik Buterin has sparked a debate over the categorization of various layer 2 scaling solutions, specifically challenging the status of Ethereum’s validiums as authentic rollup solutions.
Buterin’s statement followed a comment by Daniel Wang, the founder of Taiko, an Ethereum rollup solution, suggesting that rollups relying on external data chains, such as Celestia’s modular blockchain, should be classified as validiums.
Buterin agreed, emphasizing the core of a rollup being the unconditional security guarantee, which, in his view, validiums could not uphold if data availability depended on an external system.
Validium is a scaling solution for Ethereum utilizing zero-knowledge proofs for off-chain transactions, still relying on the Ethereum mainnet for security. Unlike ZK-rollups, validiums do not post transaction data to layer 1 but cryptographic proofs, aiming for higher scalability.
Buterin proposed terminology adjustments, suggesting terms like “security-favoring” and “scale-favoring” be replaced with “strong” and “light” for brevity.
While some supported Buterin’s proposals, there were disagreements. Ryan Berckmans argued that validiums should be considered layer 2 networks, broadening the definition to encompass both rollups and validiums.
However, an industry analytics platform, L2Beat, countered this view, stating that validiums are not layer 2 solutions. According to L2Beat, validiums introduce additional trust assumptions by not publishing data on layer 1.
Arbitrum, an Ethereum-based layer 2 network, dominates the market share among layer 2 networks, with a consistent increase in total value locked (TVL) since October. The upcoming Ethereum upgrade, incorporating changes from EIP-4844, is expected to benefit layer 2 solutions like Arbitrum by reducing transaction costs and improving network capacity.