⚡ Layer 2 Scaling

Last verified: April 2026

Layer 2 networks process transactions off the main blockchain, then submit compressed proofs back — giving users faster, cheaper transactions with the security of Layer 1.

The scaling problem

Decentralised blockchains like Ethereum face a hard trade-off: being secure and decentralised means every transaction is processed and stored by thousands of computers, which limits how many transactions per second the network can handle. When demand is high, the network congests and fees spike. This is the scaling problem, and Layer 2 networks are the leading answer.

What a Layer 2 is

A Layer 2 (L2) is a separate network built on top of a base chain (the "Layer 1", usually Ethereum) that processes transactions off the main chain, then periodically settles a compressed summary back to it. You get the speed and low cost of the L2 while inheriting the security of the L1 underneath. It's like doing many small calculations on scratch paper and only writing the final answer in the permanent ledger.

How a Layer 2 sits on top of a Layer 1 Layer 2 processes many transactions off the main chain quickly and cheaply, then periodically posts a compressed summary down to the Layer 1, inheriting its security. ⚡ LAYER 2 (e.g. Arbitrum, Base) Thousands of cheap, fast transactions happen here "Scratch paper" — do the work quickly off the main ledger compressed proof ⛓️ LAYER 1 (Ethereum) The final summary is permanently recorded here "The permanent ledger" — slower, but this is where the real security lives

Rollups: the dominant approach

Most leading L2s are "rollups," which bundle thousands of transactions together and post them to the base chain as one. There are two main types. Optimistic rollups (Arbitrum, Optimism, Base) assume transactions are valid by default and allow a challenge window to catch fraud. Zero-knowledge rollups (zkSync, Starknet, Polygon zkEVM) post a cryptographic proof that all the bundled transactions were valid, allowing faster, math-guaranteed settlement. Both cut fees dramatically compared to using the base chain directly.

Other scaling approaches

Beyond rollups, there are sidechains (independent chains with their own security that bridge to the main chain) and state channels and other techniques. Bitcoin has its own L2, the Lightning Network, for fast cheap payments. Each makes different trade-offs, but the shared goal is the same: more transactions, lower fees, without abandoning the security of the underlying chain.

Why it matters

Layer 2s are where a growing share of real crypto activity now happens, precisely because they're cheap enough for everyday use. If you find Ethereum mainnet fees too high, an L2 is usually the answer — just remember that moving funds between an L1 and an L2 uses a bridge, and in India may count as a taxable transfer worth documenting.

How to use a Layer 2

Using an L2 is usually straightforward: you bridge some assets from the base chain to the L2 (or buy directly on it), then transact as normal with much lower fees. Wallets like MetaMask let you add an L2 network in a few clicks. The main things to understand are that your assets on the L2 are represented via the bridge, and that withdrawing back to the L1 can take time — instant on optimistic rollups only via third-party liquidity, or after a challenge window otherwise.

The India angle

Bridging between an L1 and an L2 may be treated as a taxable transfer of a Virtual Digital Asset in India — the position is unsettled — so keep a record of every bridge transaction along with your trades. The lower fees on L2s are attractive, but they don't change the 30% tax and 1% TDS treatment of the underlying assets.

Polygon (L2)Arbitrum (L2)Ethereum (L1 they settle on)ZK proofs