OP Labs: Multi-Proof Design in OP Stack and Its Ecological Impact

Original title: "Multi-proof design in the OP Stack"

Written by: Mark Tyneway, OP Joint Venture; protolambda, OPLabs Researcher

Compilation: Yvonne, MarsBit

You've heard about the security benefits of multi-client networks, but what if your favorite L2 could incorporate multiple proof schemes into its design? This is what happened after the OP's mainnet upgrade to Bedrock.

Following the logic that client diversity is beneficial to the blockchain ecosystem, OP Stack turns the OP mainnet into a modular blockchain, which can also prove the diversity of solutions. When using the OP Stack and Bedrock's modular design, builders can quickly leverage any type of existing proof and ensure that the system is adaptable to future proof innovations.

Let’s delve into the technical aspects of this unique feature and discuss its wider impact on the ecosystem.

Problem: Proof Scheme in Rollup Design

Previously, rollup design iterations focused primarily on creating a proof and fitting the system to it. This approach results in limited flexibility and adaptability to changing technologies. Because of this type of design, the L2 market is mainly debated around optimistic proofs (optimistic proofs) and validity proofs (validity proofs).

When designing Bedrock, we wanted to change that narrative. Using modularity as a key design principle for Bedrock upgrades, we built a system that can accommodate multiple proof types, providing builders with a more secure and future proof solution.

Solution: Modular Design, Flexibility and Security

The ability to incorporate multiple proofs into the OP stack provides many benefits, security being the most notable. Having multiple proofs prevents a bug in any one of them from becoming a paradigm. This is similar to how multiple implementations of L1 clients provide better overall security. Vitalik wrote about how Ethereum's multi-client idea interacts with zk-evm. In that article, he pointed out that multi-client implementation is a form of technical decentralization whose main benefit is that it is resistant to errors in the network. It also leads to some form of social decentralization if multiple independent teams/stakeholders maintain an implementation. The interests of each team are factored into the calculation of the network roadmap.

Bedrock's modular design has resulted in multiple L2 client implementations in the Optimism ecosystem, this being the first of its kind in L2. Like Vitalik and Ethereum, we are extending this idea to allow OP stacks to include multiple proofs. This opens the door to adding zero-knowledge (ZK) validity proofs to the OP mainnet or other OP chains such as Base, and ensures compatibility with future developments. The OP Stack's modular design makes it easy to adopt new technologies in a safe and battle-tested manner without major changes to the code base.

how to work?

The proof system in the OP Stack is modularized through standardized on-chain APIs and off-chain Actors. This allows mixing and matching dispute contracts, facilitating the exchange of proof schemes.

Standardized on-chain API

By standardizing the on-chain API, Bedrock enables proof-of-exchange schemes as long as they implement the standardized API. This means that new proof schemes can be added dynamically, and we can even create an m(n) scheme where more than one proof scheme is required to run the bridge.

Standardize off-chain participants

Off-chain actors or bots communicate with the disputed contract. The system creates a maximum extractable value (MEV) opportunity to incentivize honest behavior and protect the system, while maintaining the principle that playing the game of dispute should always be profitable as an incentive to ensure its continued play. With this model, we are creating an open network of surveillance actors who can step in to resolve disputes to ensure the security of the system.

Two implementations of standardized off-chain actors are under investigation.

The future belongs to the super chain

The Bedrock upgrade and its support for multi-proof is in line with our vision for a scalable network that does not disrupt our ecosystem, applications, or ability to work together. As the only L2 ecosystem designed for multi-client, multi-proof simplicity, Optimism will lead the industry towards a safer, more adaptable, more collaborative, and more optimistic future.