Section 2: ZkNode Consensus Mechanism
Last updated
Last updated
zkEVM uses the PoE consensus mechanism, that is, the consensus contract (deployed on L1). The smart contract verifies the validity certificate generated by the zk-SNARK circuit to ensure that each conversion is completed correctly.
To ensure that state transitions are allowed following a predetermined set of rules, the underlying protocol in zkEVM ensures the correctness of state transitions by using validity proofs. This type of system requires two processes: transaction batching and transaction verification.
To perform these processes, zkEVM uses two types of actors: sequencers and aggregators. Under this two-tier model:
Sequencers → Propose transaction batches to the network, i.e. they aggregate transaction requests in batches and add them to the consensus contract.
Aggregator → Checks the validity of the transaction batch and provides proof of validity. Any permissionless aggregator can submit proofs proving the correctness of state transition calculations.
Therefore, the smart contract makes two calls: one to receive the batch from the sequencer, and another to the aggregator, requesting validation of the batch.
