🔐 ZK Rollups: Prove Valid Before Accepting
Understand how zkSync and StarkNet use mathematical proofs
Compare the two dominant rollup approaches
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0 / 5 completed🔐 ZK Rollups Deep Dive
Zero-Knowledge rollups take the opposite approach: prove every transaction is valid upfront using cryptographic proofs. No trust required—just math.
⚙️ How It Works
Batch Transactions
Sequencer collects thousands of L2 transactions into a single batch for efficient proving.
Generate Validity Proof
Prover runs ZK circuit to create cryptographic proof that all transactions are valid (computationally expensive).
Verify on L1
L1 smart contract verifies proof in milliseconds (very cheap, ~500K gas). Proof guarantees correctness.
Instant Finality
Once verified, state is immediately final. No challenge period. Withdrawals available instantly.
🎮 Interactive Validity Proof Simulator
Watch how ZK rollups use cryptographic proofs to guarantee transaction validity without re-executing.
1. Collect Transactions
Sequencer batches thousands of L2 transactions
Batch #5678: 10,000 transactions collected. Old state root: 0xabc...def. Ready for proving.
🔬 Types of ZK Proofs
ZK-SNARKs
Succinct Non-Interactive Arguments of Knowledge
ZK-STARKs
Scalable Transparent Arguments of Knowledge
🛡️ Security Model
✓ Advantages
- •Instant finality: No 7-day wait, withdraw immediately
- •Stronger security: Math proves correctness, no trust needed
- •Privacy potential: Can hide transaction details in proof
- •Lower data costs: Only proof needed, not full tx data
⚠️ Trade-offs
- •Expensive proving: Costs $50-200+ per batch to generate proof
- •Slower execution: Proof generation takes 5-30 minutes
- •Complex cryptography: Harder to implement and audit
- •EVM challenges: Full EVM equivalence is technically difficult
🌐 Real-World Implementations
zkSync Era
Matter Labs' ZK rollup ($500M+ TVL)
StarkNet
StarkWare's ZK rollup with Cairo VM
Polygon zkEVM
True EVM equivalence with ZK