Glossary
Layer 2 (L2)
16/04/2026
Layer 2 (L2) refers to scaling solutions built on top of a base blockchain (Layer 1) to increase transaction throughput and reduce fees, while inheriting the security of the underlying chain. Layer 2 does not replace Layer 1 — it extends it.
How Layer 2 works
Layer 2 solutions batch or process transactions off the main chain, then periodically settle the final state back to Layer 1. This means:
- Transactions on L2 are faster and cheaper than on L1
- Security ultimately still relies on the L1 consensus mechanism
- Users must bridge assets between L1 and L2
Examples
| Network | L1 | L2 | Type |
|---|---|---|---|
| Lightning Network | Bitcoin | Lightning | Payment channels |
| Arbitrum | Ethereum | Arbitrum | Optimistic rollup |
| Optimism | Ethereum | Optimism | Optimistic rollup |
| zkSync | Ethereum | zkSync | ZK rollup |
Mining happens on Layer 1
Mining secures the Layer 1 blockchain — you cannot mine directly on a Layer 2 network. Layer 2 solutions rely on the underlying PoW (or PoS) chain for security.
Relevance to miners
Miners interact with L2 when:
- Moving mined coins cheaply to another wallet or exchange using an L2 bridge
- Using DeFi protocols on L2 with lower fees
- Receiving Lightning Network payments for BTC mining payouts (some setups)
