From Real-Time Proof to Native Rollup: The Finality of Ethereum Scaling Driven by ZK

Author: imToken

Editor’s Note: Ethereum is moving towards a new era of 10,000 TPS scalability, and zero-knowledge proof (ZK) technology is becoming a key driving force. This article is the second part of our compilation of the "Ethereum 10,000 TPS Roadmap," focusing on the technical challenges of real-time proof, the participation logic of Prover, the security challenges during the L1 switching process, and how "native Rollup" can become the ultimate form of ZK scalability.

If ZK transformation is the starting point of Ethereum's technological reconstruction, then "real-time proof" and "native Rollup" are the core landing phases of this scaling revolution.

In this article, we will continue to delve into how to achieve 12-second ZK real-time proofs on the Ethereum mainnet, the hardware thresholds and incentive mechanisms for becoming a Prover, and how native Rollup will reshape the landscape of Ethereum L2.

01. Real-time Proof: The Key Piece of Ethereum Scalability

On the roadmap for Ethereum to achieve 10,000 TPS, there is an indispensable technological breakthrough: real-time proving.

Succinct co-founder Uma Roy explained: "Real-time proof refers to the ability to complete the ZK proof generation process for a block on the Ethereum mainnet in less than 12 seconds."

What does this mean? Once real-time proof is achieved, Ethereum will be able to incorporate its block validation logic into the protocol itself, and almost "arbitrarily" increase the Gas limit without sacrificing verifiability, thus achieving large-scale expansion of L1 (Editor’s note: The generation time for each block on the Ethereum mainnet is 12 seconds, so "real-time" refers to completing the proof within each block cycle).

However, to achieve real-time proof, relying solely on zkVM technology is not enough; changes to the Ethereum protocol layer are also needed.

Ladislaus from the Ethereum Foundation pointed out that a key mechanism—"decoupling block validation and immediate execution"—is expected to be introduced in next year's Glamsterdam upgrade, which will provide Provers with more time to generate zkEVM proofs within a complete slot, thereby achieving true real-time processing.

In terms of technical implementation, Succinct has released its latest SP1 Hypercube zkVM, which can generate proofs in real-time for 93% of the 10,000 mainnet blocks under a cluster of 200 GPUs.

Roy stated that they are confident in raising the success rate to 99% by the end of this year. Although some difficult-to-handle blocks may still result in a small number of blocks not generating proofs in a timely manner, the protocol design has considered fault tolerance mechanisms, such as allowing the skipping of that block to continue processing into the next block.

Furthermore, Ethereum is also considering reducing the block time from 12 seconds to 6 seconds (as another potential proposal for Glamsterdam), which would significantly enhance user experience and transaction confirmation speed, but this also puts additional pressure on ZK Prover — the difficulty of the task has doubled for the prover.

However, Roy is not worried, as ZK technology can improve performance by 10 times every year, so even if the block time is halved, it can still cope.

In June, Linea also announced that 100% of on-chain activities on its network can be covered by ZK proofs. Although Linea's current TPS is only 2, this is not a performance limitation, but rather constrained by usage demand.

It is worth noting that the block interval of Linea is only 2 seconds, and ZK proofs are uploaded to Ethereum L1 for verification through smart contracts. This model may be a precursor to the future mainnet's "ZKification."

02. Is the hardware threshold for Ethereum ZK provers high?

To generate ZK proofs in real-time, powerful computing resources are essential.

The initial technical goal set by the Ethereum Foundation for Prover is to keep hardware costs under $100,000, with power consumption below 10 kilowatts, which is roughly equivalent to the power consumption level of a Tesla Powerwall home battery.

This number does not sound "lightweight"; Ethereum critic Justin Bons (founder of Cyber Capital) referred to it as "mad hardware requirements far beyond Solana's validator nodes," but this actually confuses two completely different roles.

Ladislaus from the Ethereum Foundation's protocol coordination team pointed out that the responsibilities of Provers and Validators are different and cannot be confused—Validators run nodes and participate in consensus; whereas the task of a Prover is to generate ZK proofs. Once the ZK proof for a transaction is correctly generated, the network only needs to verify whether that proof is correct, without the need to re-execute the transaction.

For this reason, Ladislaus expressed optimism, stating, "As long as we can find an honest prover that meets the hardware requirements, Ethereum can continue to operate safely. We deliberately set the threshold below that of data centers, and even if it’s not a large institution or data center, as long as there are technically capable individual developers, they can run the Prover at home."

Currently, this hardware configuration of $100,000 is just an initial goal. Ethereum Foundation researcher Sophia Gold expects that mainstream Provers are likely to meet this target before the Devconnect Argentina developer conference in November this year.

Succinct co-founder Roy expects that by early next year, GPU demand can be reduced to around 16 graphics cards, with total costs controlled between $10,000 and $30,000.

At the same time, Succinct has built a decentralized network consisting of "hundreds of Provers" on the testnet, generating millions of proofs in total.

The core logic of this system is competitive proof, where all Provers participate in bidding, and in each round, one winner is selected to execute the zk proof. The goal is to allow the participant with shorter time and lower cost to win, forming a type of computational power bidding mechanism.

This means that in the future of Ethereum driven by ZK, the spirit of miners will reappear in another form - only the role has changed from calculating blocks to calculating proofs.

03. Mainnet transition to ZK architecture: a challenging system migration.

Switching the Ethereum L1 mainnet to a zero-knowledge proof (ZK) architecture is yet another technical challenge of almost the same magnitude as the transition from proof of work (PoW) to proof of stake (PoS) in 2022. The entire process requires not only a reconstruction of the protocol layer but also a thorough consideration of various potential edge cases and security risks to prevent network interruptions.

At an EthProofs conference in July this year, researcher Justin Drake mentioned several potential risks. For example, malicious attackers might insert what is called a "prover killer" into the block, causing the entire network's verification mechanism to fail; or there could be a sudden drop in network activity, resulting in transaction fee income that is insufficient to cover the costs of generating ZK proofs, thereby affecting the network's sustainability.

Ladislaus from the Ethereum Foundation's protocol coordination team stated that the entire transition process may take years, especially with a focus on security risks. The ZK virtual machine (zkVM), as a complex technology still in its early stages, is highly likely to have various vulnerabilities. However, as the ecosystem matures, we can gradually enhance its feasibility and robustness on Ethereum L1 by introducing proof diversity, improving incentive mechanisms, and employing formal verification.

At the same time, Ethereum plans a fundamental architectural restructuring of its consensus layer, specifically by building a new structure called "Beam Chain," with the goal of being friendly to ZK optimization from the outset of design. Drake even stated that in the future, the entire data verification work of Ethereum could be done on the CPU of a regular laptop.

04. Mainnet "Snarkification": Native Rollup is coming.

As the zkEVM is integrated into the Ethereum mainnet, another long-term vision is gradually emerging: Native Rollup.

Currently, Rollups (whether Optimistic or ZK type) use independent proof systems, and their security relies on their own validators or sequencer mechanisms, which involves a certain degree of trust assumption with the Ethereum mainnet.

The vision of "native Rollup" is completely different – by integrating zkEVM into the mainnet, allowing Ethereum L1 validators to directly verify the state transition proofs of Rollup, thereby achieving a truly mainnet-validated and mainnet-secured L2.

This requires adding a key piece of code "execute precompile" in the Ethereum L1 client, allowing validators to directly verify the ZK state transition proofs generated by L2. As Ethereum Foundation protocol coordinator Ladislaus stated, "L1 validators will consume these Rollup execution proofs and verify their correctness."

In other words, if native Rollup becomes a reality, then in the future, whether it is a transaction occurring on L1 or a transaction occurring on the native Rollup, its final settlement and security will be guaranteed by the same group of Ethereum validators, and the level of trust will be completely equivalent.

This means that depositing 10 million dollars on the native Rollup will have the same security as directly depositing on the Ethereum mainnet.

Declan Fox, the project leader of Linea, stated that their long-term goal is to become a native Rollup. He believes this is an "upgraded version" of the ETH 2.0 sharding scheme - no longer operating 64 identical shard chains rigidly, but instead constructing a heterogeneous Rollup system in a highly programmable and customizable way to serve different scenarios and user needs.

Unlike the homogeneous sharding architecture of ETH 2.0 in the past, native Rollups can be heterogeneous, providing end users with a more diverse and differentiated application experience.

Although native Rollup has not yet been officially incorporated into the Ethereum roadmap, with the official launch of zkEVM and the gradual restructuring of L1 architecture, it is clear that setting up its preset interfaces and precompiled logic has become a foreseeable technological trend.

Ladislaus concluded, "There is a high degree of technical synergy in Ethereum between the EVM Snarkification (i.e., integrating ZK proof capabilities) and the advancement of native Rollups, as both share the underlying ZK technology stack." Of course, this process still needs to be governed by the Ethereum community, forming EIPs (Ethereum Improvement Proposals), and ultimately be deployed in a hard fork.

If everything goes smoothly with optimistic expectations, we may be able to submit the relevant EIP by the end of the year and go live in the fork after the Glamsterdam upgrade.

However, this timetable still carries a high degree of uncertainty and should be viewed with caution.