ethereum co-founder Vitalik Buterin introduced a new concept for the blockchain platform called “ethereum Zero-Knowledge Virtual Machine Enshrined (ZK-EVM) in a ethereum.org/@vbuterin/enshrined_zk_evm”>Blog post from December 13.
The primary goal of the proposal is to substantially improve the efficiency and security of ethereum's Layer-2 protocols, which include optimistic and ZK rollups.
Address challenges in layer 2 protocols
Buterin's proposal arises from the need to rationalize current Layer-2 solutions on ethereum. These protocols, vital to ethereum's scalability, rely heavily on EVM verification, which currently involves relying on a large and potentially vulnerable codebase.
Additionally, ZK-EVMs, designed to mimic the Layer 1 EVM, face the challenge of keeping up with changes to the core ethereum protocol, leading to redundant efforts and a higher risk of security flaws.
Buterin's proposed solution involves integrating a ZK-EVM directly within the ethereum network. This internal ZK-EVM would take on the task of verifying layer 1 ethereum blocks, thus offering a more efficient and secure approach.
As ethereum advances, particularly with the development of light clients using ZK-SNARK, the concept of a native ZK-EVM becomes increasingly practical and attractive.
Central aspects of the ZK-EVM proposal
Buterin envisions ZK-EVM to primarily focus on verifying ethereum blocks by processing inputs such as a pre-state root, a block, and a post-state root.
This would ensure the integrity of the post-state root as the actual result of the block execution. The proposal also aligns with ethereum's multi-tenant philosophy, supporting the use of diverse testing systems and emphasizing the importance of data availability and auditability.
Implementing a ZK-EVM, as described by Buterin, presents several design challenges and trade-offs. Essential properties include:
- Compatibility and adaptability: The system must be flexible enough to support multiple test systems, reflecting ethereum's commitment to a multi-tenant environment.
- Ensure data availability: Vital to allow verification by different clients.
- Emphasizing auditability and updateability: Allowing easy inspection and quick solutions to any problems without the need for hard forks.
- Supporting innovations in 'near-EVM': Allow Layer 2 solutions to extend and innovate standard EVM functionalities.
A crucial part of Buterin's debate revolves around the choice between an open multi-client system, where tests are verified externally, and a closed system with predetermined test systems. Buterin advocates for a system available for its flexibility and compatibility with the fundamental principles of ethereum despite its greater complexity.
Buterin emphasizes that speed is critical for ZK-EVM implementations. With technological advances in parallelization and hardware acceleration, the goal is to reduce test generation time, allowing for near-instant processing.
