Brevis coChain

This is a roadmap item that is not currently available. We are documenting the solution here because it can significantly reduce the cost of using ZK Coprocessors and enable more features in the near future. Read more details in the blog post.

Brevis currently operated in a “pure-ZK” model. In this model, ZK proofs for data access and computation results are always generated upfront. Smart contract applications could utilize these results only after the on-chain verification of the ZK proofs.

While the pure-ZK model provides simplicity and a trustless framework to work from, it is not without its own set of drawbacks:

  • High Proof Generation Costs and Limited Scalability: While Brevis delivers world-leading performance in ZK Coprocessing, and we are confident in the innovations of ZK performance optimization, we must acknowledge the fundamental computational overhead introduced by ZK at this current stage. The costs of ZK proof generation and the resulting delays still present challenges. These costs ultimately contribute to a suboptimal user experience and act as barriers to the widespread adoption of data-driven dApps.

  • Inability to Generate Proofs for Some Key Use Cases: Within the pure-ZK model, it is extremely challenging to generate proofs of non-existence. As an example, proving that a user did not engage in a transaction with a specific protocol using ZK is very difficult to do. It would require a comprehensive ZK proof encompassing every transaction across all historical blocks—a feat that is practically infeasible. However, non-existence proofs can be utilized in important use cases such as new user acquisition, identity, account abstraction and compliance.

These limitations, if left unaddressed, render ZK Coprocessors impractical for numerous high-value applications, especially those involving substantially large amounts of data and users, where maintaining a minimal cost per user is crucial.

This is why we are introducing Brevis coChain.

Brevis coChain is a Proof-of-Stake (PoS) blockchain featuring on-Ethereum staking and slashing functionalities. It accepts coprocessing requests from smart contracts and “optimistically” generates coprocessing results through PoS consensus. These PoS-generated results are submitted to blockchains as “proposals” that are subject to be “challenged” via Zero-Knowledge (ZK) proofs. Successful ZK-proof challenges will trigger the slashing of the corresponding validators’ stakes directly on Ethereum. If no challenge is initiated, the results can be used by dApps directly without incurring ZK proof generation costs. Additionally, Brevis coChain is set to integrate with EigenLayer, empowering developers to dynamically adjust the level of crypto-economics security used in the proposal stage. This fusion of crypto-economics and ZK proofs not only ensures the secure and trustless nature of Brevis but also provides developers with a versatile tradeoff space to explore so they can design according to their specific use case.

Also as an important note, developers will be able to seamlessly integrate with Brevis coChain with no extra effort required. By leveraging the Brevis SDK, you only need to write the application’s business logic once. Then, you have the flexibility to deploy their applications in either the “pure-ZK” model or the coChain model once Brevis coChain is launched.

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