Vitalik: Solving the three dilemmas of blockchain, promoting zkEVM adoption in 2026

Vitalik Buterin on Saturday on X claimed that Ethereum has “solved” the three blockchain challenges. PeerDAS is now live on mainnet, and zkEVM has achieved production-level performance. Buterin states that “it’s not just talk on paper, but actual running code,” with only security enhancements remaining. Full realization is expected between 2026 and 2030.

What is the three blockchain challenges? Why are they hard to solve?

The three blockchain challenges refer to the complexity of building a blockchain network that simultaneously achieves decentralization, security, and scalability, with these three pillars not interfering with each other. Generally, most blockchains in their early stages prioritize one or two of these pillars—such as speed and security—and then gradually work to balance all three.

In his post, Buterin uses Bitcoin as an example, pointing out that the network’s design goal is “high decentralization” and security, but it faces scalability issues. Bitcoin can process only about 7 transactions per second, far from supporting global payment needs. Conversely, many emerging public chains sacrifice decentralization to pursue high throughput, using fewer nodes for validation, which speeds up transactions but raises security concerns.

The difficulty in solving this dilemma lies in the physical contradictions among the three. Increasing scalability typically requires larger blocks or faster block times, which raises node operation costs, causing small nodes to drop out and reducing decentralization. Enhancing security requires more validation nodes to participate in consensus, which can slow transaction confirmation times and harm scalability. Achieving all three simultaneously without sacrificing any is the ultimate challenge in blockchain technology.

Buterin states that Ethereum has taken a decade of solid effort to reach a level capable of solving these three challenges, noting that he published his first article on data availability issues back in April 2017. “It’s been a ten-year journey, but it has finally been realized.” Behind this statement are the continuous efforts of thousands of developers and the accumulation of dozens of technological iterations.

PeerDAS and zkEVM dual breakthroughs

On Saturday, Buterin emphasized on X the potential of peer data availability sampling (PeerDAS) and zero-knowledge Ethereum Virtual Machine (zkEVM), pointing out that these two upgrades make Ethereum “a whole new, more powerful decentralized network.” “Now, with Ethereum’s PeerDAS (2025) and ZK-EVM (expected to be used by a small part of the network in 2026), we will achieve: decentralization, consensus, and high bandwidth.”

PeerDAS was introduced in Fusaka’s December upgrade, enhancing scalability by enabling Ethereum to handle more data. Traditional data availability schemes require all nodes to download and store complete block data, which demands high hardware requirements. PeerDAS uses sampling techniques, allowing nodes to verify integrity by downloading only parts of the data, greatly reducing hardware barriers and increasing decentralization.

Meanwhile, the already existing zkEVM is a virtual machine compatible with ZK proofs and the current Ethereum Virtual Machine. The core innovation of zkEVM is using zero-knowledge proofs to compress transaction verification, allowing mainnet nodes to verify only a short proof instead of re-executing all transactions. This technology can increase transaction throughput dozens of times while maintaining security.

Ethereum’s solution to the three blockchain challenges

Decentralization (PeerDAS): Sampling technology reduces hardware requirements for nodes, enabling more people to run nodes

Security (zkEVM): Zero-knowledge proofs ensure transaction correctness without full network re-verification

Scalability (combining both): Data processing capacity and transaction throughput are increased by dozens of times simultaneously

Buterin states that zkEVM is still in “alpha” stage, with performance meeting standards but security needing further improvement. He provides a four-year timetable for full deployment of zkEVM in Ethereum: “The three challenges are already solved, not just talk on paper, but through actual running code. Half (data availability sampling) is already live on mainnet, the other half (zkEVM) has achieved production-level performance, and only security remains.”

Roadmap for full realization from 2026 to 2030

“In the next roughly four years, this vision is expected to be fully realized: by 2026, with the emergence of BAL and ePBS, gas limits not relying on zkEVM will be significantly increased, and we will see the first opportunities to run zkEVM nodes,” Buterin said.

“From 2026 to 2028, gas re-pricing, state structure changes, payloads entering blobs, and other adjustments will be made to ensure higher gas limits safely. From 2027 to 2030, gas limits will be substantially increased, as zkEVM will become the primary method for verifying blocks on the network,” he added.

This timetable shows that although Buterin claims the three challenges are “solved,” full implementation still takes years. Only a small part of the network will adopt zkEVM in 2026, with mainstream validation expected between 2027 and 2030. This gradual deployment is for security reasons; new technologies must undergo thorough testing before large-scale adoption.

From an investment perspective, Ethereum’s narrative of solving the three blockchain challenges provides long-term support for ETH price. If the technical upgrades proceed as planned, Ethereum will become the only platform that simultaneously satisfies decentralization, security, and high performance for smart contracts. This technological moat will attract more dApps and institutional adoption. However, the four-year timeline also means that short-term performance improvements may not be immediately reflected, requiring investors to be patient.