Polygon Labs wants to help convert EVM blockchains into validiums via 'type 1 prover'

Last week, Polygon MATIC -2.070% introduced the “type 1 prover”— a technology that can facilitate EVM-compatible chains to adopt zero-knowledge proofs.

The type 1 prover is expected to be released later this year. It will be incorporated into Polygon’s CDK (software stack), marking an advancement over the project’s previous type 2 proving mechanism, which lacked compatibility with other EVM chains. “The type-1 prover can generate zero-knowledge proofs for any EVM chain without necessitating hard forks or adjustments to existing clients,” Brendan Farmer, a co-founder of Polygon, told The Block.

Polygon Labs wants to leverage the prover to transition a wide range of blockchains, including side chains and optimistic roll-ups, into validiums — a specialized form of Layer 2 networks that utilize zero-knowledge proofs for enhanced efficiency and reduced transaction costs.

Validiums store only zk-proofs on the Ethereum mainnet, with actual transaction data held off-chain, supported by a data availability solution. This structure contrasts with ZK-Rollups, which also have to publish proofs of app data on the Ethereum mainnet.

Farmer stressed that projects can also choose to become full-fledged ZK-rollups if they want to make use of their type-1 prover. At the end of the day, it’s up to the teams to make that decision, he clarified.

The move to ZK-based network

Moving to a ZK-based network (like validiums or ZK-rollups) can potentially offer advantages to Layer 2 projects, including the elimination of the seven-day withdrawal delay associated with optimistic rollup solutions (e.g., Optimism and Arbitrum).

This delay, Farmer said, has been a point of contention because it incurs additional time and costs for users relying on third-party bridges for transactions.

“It’s like tens of millions of dollars paid to third-party bridges, and if you look at what it would have cost to prove all of the transactions on those optimistic rollups, it’s like a few hundred thousand dollars,” Farmer added. “Users are being forced to bear a lot of costs on Optimistic Layer 2s that are just unnecessary, and an upgrade to a ZK-based network just fixes this.”

Following the ZK transition, chains can be connected through Polygon’s interoperability protocol — the AggLayer — which promises interoperability and unified liquidity for Layer 2s. The first version of the AggLayer is planned to be released in February, enabling developers to connect blockchains.

The objective will be to ensure uniform security across modular and monolithic chains, including those within the Polygon ecosystem. AggLayer will be a critical component of Polygon 2.0, the next iteration of the Polygon network. Unlike typical interoperability solutions, it will aggregate ZK proofs from all connected chains.