Key takeaways

  • Ethereum rollups must move away from centralized sequencers, allowing multiple, independent actors to order transactions, reducing censorship risk.
  • Rollups must use trustless bridges to interact with Ethereum, removing reliance on centralized intermediaries for moving assets or data.
  • Proof generation (like ZK-proofs) must become decentralized, allowing anyone to participate and enhancing security and trustlessness.
  • Participating in running rollups (validating, sequencing, or proving) should be permissionless from centralized entities.

When Vitalik Buterin spoke about “the training wheels coming off” for rollups, he was referring to the current phase, where many rollups still rely on centralized components or safeguards to ensure security and functionality. 

These “training wheels” are temporary, helping rollups scale and operate safely during their early stages of development. Still, they also introduce points of centralization and trust assumptions, which can be security risks.

As rollups evolve and mature, the goal is to remove the centralized components and safeguards, making the rollups fully decentralized and trustless. This means:

  • No reliance on centralized sequencers (for transaction ordering).
  • Trustless, permissionless systems for generating proofs (like ZK-proofs).
  • Fully decentralized governance and infrastructure.

Buterin’s idea of the “full decentralization” for rollups is about making these scaling solutions on Ethereum more secure, censorship-resistant and independent from centralized control. While rollups help Ethereum scale by processing transactions offchain, they still rely on some centralized parts. This is especially true when it comes to transaction ordering or governance. 

Did you know? Blockchain roll-ups improve scalability by bundling transactions off-chain, reducing costs and congestion, while still preserving security and decentralization.

Complete decentralization aims to eliminate these weak spots:

Decentralized sequencers

In the current setup, many rollups depend on centralized sequencers that decide the order of transactions. That’s a potential vulnerability as, if one entity controls the sequencing, they could censor or manipulate transactions. 

Buterin’s vision for complete decentralization would mean handing this job to multiple decentralized sequencers. Think of it like having a network of independent validators, each playing a part in the process instead of just one central player.

Moving beyond “training wheels”

Rollups are now in an in-between stage of decentralization. They still rely on a combination of offchain and onchain data, which can create security trade-offs. 

Buterin’s full decentralization vision means losing the “training wheels,” making rollups completely secure and reliant on Ethereum’s security without needing extra layers of trust.

Trustless bridges to Ethereum

Rollups interact with Ethereum as their main settlement layer, but many use centralized or semi-centralized bridges to move assets or data back and forth. 

Full decentralization would aim to make these bridges trustless, so no single party has control. Essentially, assets could flow between the rollups and Ethereum without relying on anyone’s permission or trust.

Decentralized provers

In rollups like ZK-rollups, proofs are needed to verify that transactions are valid. Currently, these proofs might be generated by a few centralized parties, but full decentralization would mean anyone could participate in the process. 

It means opening up the system so the proof generation is spread among a decentralized network, making it more secure and less vulnerable to control.

Did you know? zk-SNARKs and zk-STARKs are cutting-edge cryptographic proofs that enhance privacy and scalability in blockchain. zk-SNARKs (Succinct Non-Interactive Arguments of Knowledge) are smaller and faster but require a trusted setup, while zk-STARKs (Scalable Transparent Arguments of Knowledge) are trustless, more scalable, and secure, though computationally heavier. Both enable verifying data without revealing the data itself!

Permissionless participation

For rollups to be genuinely decentralized, they must allow anyone to participate. Participation could be across validating transactions, being a sequencer or generating proofs. 

In other words, no one should need special permission to help run the network. This would shift rollups from a more “controlled” environment to a fully open one.

Decentralized governance

Many rollups are still governed by core teams or centralized entities, but to reach full decentralization there must be a shift toward decentralized governance. 

Whether through onchain voting systems or community-driven decision-making processes, the idea is that the future development and management of rollups should be in the hands of the users and the broader community, not just a few people.

Censorship resistance

One of the most important goals of decentralization is censorship resistance. When there’s a single sequencer or bridge, it’s easier for someone to pressure them into censoring certain transactions. 

If you spread control across a decentralized network, it becomes much harder for anyone to interfere or block transactions.

What this means for Ethereum and rollups

If rollups achieve full decentralization, they wouldn’t just serve as a solution to scale Ethereum,  they would evolve into self-sustaining ecosystems with minimal trust assumptions. While continuing to inherit Ethereum’s security, they would no longer depend on centralized entities, enhancing their resilience and aligning with Ethereum’s broader goal of mass adoption. This is especially important as Ethereum progresses through its next scaling phase, known as “The Surge.”

In short, Buterin’s full decentralization vision is about turning rollups into fully trustless, secure and open systems. It’s a big step toward making Ethereum more scalable while staying true to its decentralized ethos.

Written by Arunkumar Krishnakumar