L2s & Bridges

Scale with Layer 2 solutions

⏱️ 20 min

Layer 2s & Bridges

Layer 2 solutions help blockchains scale by processing transactions off the main chain.

The Scaling Problem

Ethereum mainnet can only process ~15 transactions per second. When busy, this causes high fees and slow confirmations.

Layer 2 Solutions

Rollups bundle many transactions and post compressed data to Layer 1.

Optimistic Rollups

- Assume transactions valid, allow challenges

- 7-day withdrawal period

- Examples: Arbitrum, Optimism, Base

ZK Rollups

- Prove validity with cryptographic proofs

- Faster withdrawals

- Examples: zkSync, StarkNet, Polygon zkEVM

Benefits

- 10-100x cheaper fees

- Faster confirmations

- Same security as mainnet (eventually)

- Growing ecosystem

Bridging

Moving assets between chains/layers.

Native Bridges: Official bridge for each L2

- Safest option

- May have waiting periods

Third-party Bridges: Hop, Across, Stargate

- Faster

- Additional smart contract risk

Bridge Safety

Bridges are high-risk targets (billions stolen).

- Use official bridges when possible

- Double-check URLs

- Start with small amounts

- Consider the trade-off: speed vs security

Getting Started

1. Add L2 network to MetaMask (use chainlist.org)

2. Bridge small amount using official bridge

3. Explore apps on the L2