Modular Proof Verification

Modular proof verification describes an approach in which the job of checking cryptographic proofs, especially zero-knowledge proofs, is handed to a dedicated network or layer rather than performed directly on a general-purpose blockchain such as Ethereum. Systems such as ZK-rollups regularly submit proofs that must be verified before their results are accepted, and doing this on Ethereum can cost a significant amount in gas fees. A specialised verification layer can check many proofs more cheaply, support proof systems that Ethereum does not natively handle, and then pass on a compact confirmation of the results. The idea follows the wider "modular" trend of splitting blockchain functions such as execution, data availability and settlement into separate layers. The trade-off is an extra layer of trust and complexity. The term is used mainly by projects building such layers and has no single settled definition.