Remove the Rollup auxiliary wheels, how can L2 start the road to decentralization?

Economic decentralization and community joint governance may be the passcode for L2’s decentralization path.

Written by: NingNing

Recently, the MIP-4 proposal of the Metis community was passed. This is the first among all L2 companies to start decentralized sequencer testing, which also means that Metis has begun the special action of removing the Rollup training wheels.

The concept of Rollup training wheels comes from Vitalik. In November 2022, Vitalik posted on the Ethereum community forum to discuss milestones in the development of Rollup L2. He proposed to set 3 milestones, which are:

Stage 0: Full training wheel stage

Rollup L2 in stage 0 allows the use of a centralized sequencer to package and submit all state data of L2 to L1 (Ethereum main network), and at the same time deploy a set of verification smart contracts on L1 (such as Optimism deployed on the Optimism Gateway of the Ethereum main network) ) to ensure data availability and ensure that users can freely transfer assets without permission.

Phase 1: Limited training wheel phase

For Rollup L2 in phase 1, OP-Rollup needs to deploy a fraud certificate in L1, and ZK-Rollup needs to deploy a validity certificate in L1.

A multi-signature “security committee” with the authority to override the error output of fraud proofs and validity proofs is required.

An upgrade mechanism is allowed, but the time lock has a delay of at least 7 days.

Phase 2: No auxiliary wheel phase

There must be two independent fraud proof contracts or validity proof contracts that back up each other. When a conflict of state data occurs, the “Security Committee” will adjust according to the situation.

An upgrade mechanism is allowed, but the time lock has a delay of at least 30 days.

After publishing this post, Vitalik was very Bullish Rollup of these 3 milestones. He was optimistic that L2 would reach at least the Phase 1 milestone after the Cancun upgrade.

However, since the Cancun upgrade was split from the Shanghai upgrade into an independent major upgrade, and the deployment time has been repeatedly delayed, all Rollup L2s are still in stage 0.

There are two reasons for this phenomenon:

1. The smart contract that implements the fraud proof mechanism has a complex structure, requires a large amount of on-chain computing and verification resources, and has very high operating costs. The probability of events requiring fraud challenges is very low. At least so far, there has not been a single state conflict event in many OP-Rollup L2s.

It is uneconomical to invest high costs for small-probability events. Even if economic factors are not considered but only to enhance security, the L2 development team hopes to deploy it after the Cancun upgrade significantly reduces L2 operating costs.

2. Some L2s are vested interests in stage 0. Relying on the L2 hair-raising craze and the centralized sequencer, it can generate operating income of more than 10 million US dollars per month from users. They lack the motivation to move into Phase 1 or Phase 2.

Faced with the status quo of L2, which is still and addicted to stage 0, the patience of the market and users has gradually exhausted.

There have been more and more criticisms of L2 recently, focusing on the delay in launching fraud proof testnet verification, serializer centralization, endless task MEV user gas fees, etc.

In the face of these criticisms, some L2s use the ideology of Ethereum Maxi as a shield, believing that the decentralized sequencer’s establishment of independent/semi-independent consensus is decoupling from Ethereum.

Some L2 believe that there is a fractal relationship between L2 and Ethereum. The decentralized sequencer is, to a certain extent, the fractal of the Ethereum PoS consensus mechanism at the L2 level.

L2s that hold this attitude include Starknet and Metis. Among them, Starknet chooses 1/3 of the Gas fee protocol token STRK to pay for balance, which can be said to be 1/3 of the sovereign rollup. Metis, as “Vitalik fucking L2”, is more determined in choosing the path of sovereign Rollup and decisively started the decentralized sequencer test this month.

Centralized sequencer or decentralized sequencer, this is a huge question for every L2.

Let’s put aside the political correctness of Ethereum’s legitimacy and only analyze the methodology of L2 construction.

The current L2 construction methodology is vaguely divided into two factions. One group insists on the supremacy of the legitimacy of Ethereum and the supremacy of developers, and uses fraud proof/validity proof technical solutions to achieve minimal trust and decentralization of L2. The other group agrees that the community is the largest and users are king, and uses the architecture of decentralized sequencer + sovereign rollup to achieve L2 decentralization.

We have no intention of getting involved in this dispute, but just want to state a basic fact: the web3 protocol is not a web2 product. The process of building the web3 protocol is more similar to building a biosphere ecosystem, rather than building an industrial product like web2 products.

This is why the Metis community emphasizes the principles of diversity, tolerance, and sharing, and this is why Metis still promotes the decentralization of the sequencer despite some doubts from Ethereum Maxi.

Economic decentralization and community co-governance may be the passcode for L2’s decentralization path.

Finally, as the Bitcoin ecosystem, the rise of modular public chains, and the Ethereum ecosystem compete for the right to define the future Web3 paradigm, the Ethereum ecosystem needs to restrain its e/acc impulse and listen to the voices of the community more than before.