Vitalik Buterin, the co-founder of Ethereum, expressed his optimism about the development of rollups, a layer 2 scaling solution that aims to increase the throughput and lower the fees of the network.
In a Warpcast on December 27, 2023, Buterin said,
“I’m really happy we have one unambiguously stage 1 rollup (and a couple more very-close-to-stage-1 rollups) this year. Real decentralization. Let’s get to ten stage 1 rollups, and some degree of sequencer decentralization, in the next year.”
Stages in The Ethereum Roll-up Plan
Rollups are a technique that bundles or “rolls up” transactions into a single transaction on a sidechain, which periodically submits proofs to the main chain. This reduces the load and the cost on the main chain, while preserving its security and decentralization.
According to the Ethereum roadmap, rollups have three stages of development:
- Stage 0: The rollup has a fully functional proof system, but users need permission to exit and there is no security council.
- Stage 1: The rollup has a fully functional proof system, at least five external participants can submit fraud proofs, users can exit without permission, and the security council is correctly established.
- Stage 2: The rollup has a fully functional proof system, at least 15 external participants can submit fraud proofs, users can exit without permission, the security council is correctly established, and the rollup is interoperable with other rollups.
Buterin’s Vision for Rollups
- Stage 1 rollups: These rollups have a fully functional proof system, allowing them to securely batch and verify transactions off-chain before submitting them to the Ethereum mainnet.
- Sequencer decentralization: Currently, a single entity operates the sequencer in most rollups, which is a potential centralization point. Buterin wants to see this power distributed among multiple independent parties.
Arbitrum One, A Trail Blazer
Buterin said that reaching stage 1 was a significant milestone for rollups, as it meant that they were “fully trustless” and “ready for mainstream adoption”. He added that stage 2 was “nice to have” but not essential.
Arbitrum One, launched in May 2022, is the first and only rollup to achieve stage 1 status so far. It claims to offer 100x scalability and sub-second finality for Ethereum applications. Other rollups that are close to stage 1 include Optimism, zkSync, and StarkNet.