Rollups take thousands of Ethereum transactions, compress them into a single proof, and post it to L1. Explore how Layer 2 scaling works — from execution to settlement.
A rollup is a Layer 2 scaling solution that executes transactions off-chain, then bundles and posts compressed data back to Ethereum (L1), inheriting its security.
Transactions execute on the L2 network, not on Ethereum mainnet. This removes computation from the expensive L1 environment.
execute(txBatch) → stateRoot
Hundreds of transactions are compressed into calldata and posted to L1. Data availability is maintained while costs are amortized across the batch.
compress(txs[]) → calldata
A state root commitment is posted to Ethereum. The L1 contract verifies validity — either via fraud proofs or zero-knowledge proofs.
settle(stateRoot, proof)
Follow the lifecycle of a transaction as it flows from user submission to final L1 settlement.
A user signs and submits a transaction to the L2 sequencer via RPC.
The sequencer collects transactions, orders them, and executes them against current L2 state.
Transactions are compressed and bundled into a batch. Calldata size is minimized using delta encoding and zero-byte optimization.
A validity proof (ZK) or a challenge window opens (Optimistic). The state transition is cryptographically committed.
The batch and proof are posted to Ethereum. The L1 rollup contract verifies and stores the new state root. Transaction is finalized.
Two major paradigms, each with tradeoffs in proof speed, trust assumptions, and EVM compatibility.
Assume valid, challenge if not
Transactions are posted to L1 and assumed valid. Any user can submit a fraud proof during the challenge window (7 days) to dispute an invalid state transition.
Prove validity cryptographically
A zero-knowledge proof is generated for each batch, cryptographically proving all transactions are valid without revealing private data. L1 verifies instantly.
Real-time metrics from the rollup ecosystem. Figures update to reflect the expanding L2 landscape.
Investigate rollup components. Each layer contributes to security, speed, and decentralization.
Orders and executes transactions. Central point of liveness but not safety — even a malicious sequencer cannot steal funds.
Generates cryptographic proofs of state transitions. ZK provers use SNARKs/STARKs; optimistic systems rely on verifiers to spot fraud.
Transaction data posted to Ethereum (calldata / blobs via EIP-4844). DA ensures anyone can reconstruct L2 state without trusting the sequencer.
The canonical L1 contract that locks assets for L2 deposits and releases them on verified withdrawals. The trust anchor of the entire system.
EIP-4844 introduced blob transactions — cheap, temporary data storage for rollup calldata. Reduced L2 fees by up to 10x at launch.
The Ethereum roadmap targets 64+ blob columns, enabling rollups to scale to millions of TPS while maintaining cryptographic security guarantees.
Rollups are the foundation of Ethereum's scalability roadmap. Deploy on existing rollup infrastructure today and inherit L1 security at a fraction of the cost.