OP Stack's Multi-Proof Design: Enhancing Security and Flexibility

The security advantages of multi-client networks are well known, but have you ever thought about integrating multiple proof schemes into your favorite L2 design? This is exactly the new feature after the OP mainnet upgrade to Bedrock.

Following the concept that client diversity benefits the blockchain ecosystem, OP Stack transforms the OP mainnet into a modular blockchain while supporting a variety of proof schemes. With the modular design of OP Stack and Bedrock, developers can quickly apply various existing proof methods and ensure that the system can adapt to future innovations.

Let's delve into the technical details of this unique feature and explore its wide-ranging impact on the entire ecosystem.

Challenges of Proof Schemes in Rollup Design

Previously, rollup design iterations primarily focused on creating a single proof and adapting the system to it. This approach limited the system's flexibility and adaptability to rapidly changing technologies. As a result, discussions in the L2 market mainly revolved around Optimistic Proof and Validity Proof.

When designing "Bedrock", we decided to change this approach. We made modularity the core design principle of Bedrock upgrades, building a system that can adapt to various proof types, providing developers with safer and more forward-looking proof solutions.

Modular Design: Enhancing Flexibility and Security

Integrating multiple proofs into the OP Stack brings many advantages, with security being the most prominent. Multiple proofs can prevent errors in a single proof from becoming a bottleneck for the system, which is similar to the principle that multiple implementations of L1 clients provide higher overall security.

The modular design of Bedrock has led to the emergence of multiple L2 client implementations within the Optimism ecosystem, which is a first in the L2 space. We are further expanding this concept to allow the OP Stack to incorporate various proof methods. This paves the way for adding zero-knowledge (ZK) validity proofs to the OP mainnet or other OP chains (such as Base), while ensuring compatibility with future technological developments. The modular design of the OP Stack enables it to easily adopt new technologies while ensuring security and reliability, without the need for significant changes to the codebase.

How It Works

The proof system in OP Stack achieves modularity through standardized on-chain APIs and off-chain participants. This allows for the mixing and matching of dispute contracts, making it easier to replace proof schemes.

standardized on-chain API

Bedrock makes it possible to change proof schemes by standardizing on-chain APIs, as long as the new scheme implements the standard API. This means that new proof schemes can be dynamically added, and it is even possible to create a m(n) scheme that requires multiple proof schemes to operate together.

Standardized Off-chain Participants

Off-chain participants or bots interact with dispute contracts. The system creates maximum extractable value (MEV) opportunities to incentivize honest behavior and protect the system, while adhering to the principle that participating in dispute games should always be profitable to ensure their ongoing operation. Through this model, we are establishing an open network of monitoring participants who can intervene to resolve disputes, thus ensuring the security of the system.

Currently, the implementation of two standardized off-chain participants is under research.

Looking Ahead: The Era of Superchains

The Bedrock upgrade and its support for multiple proofs aligns with our vision of a scalable network that does not compromise ecosystems, applications, or interoperability. As the only L2 ecosystem designed for the simplicity of multiple clients and multiple proofs, Optimism will lead the industry towards a safer, more adaptable, more collaborative, and more optimistic future.