Ethereum layer 2 Overview

When exploring Ethereum layer 2, a collection of protocols that shift transactions off the main chain to boost speed and cut fees. Also known as Ethereum L2, it retains the security guarantees of the base network while enabling higher throughput.

One of the most common L2 designs is Optimistic Rollup, a scaling method that assumes transactions are valid and only runs a fraud proof when someone disputes a batch, sometimes referred to as Optimistic L2. Zero-knowledge Rollup, or ZK Rollup, uses cryptographic proofs to confirm transaction correctness instantly, offering near‑instant finality and strong privacy. Both rollup types require a Token Bridge, software that locks assets on Ethereum and mints their equivalents on the L2 chain, to move value safely between layers. A Sidechain, an independent blockchain that runs parallel to Ethereum and periodically syncs state, also relies on similar bridging mechanisms but often sacrifices some security for flexibility.

These components together form a ecosystem where DeFi apps, NFT marketplaces, and game platforms can run at a fraction of the gas cost they would on mainnet. An Optimistic Rollup might handle hundreds of trades per second, while a ZK Rollup can settle complex transactions in seconds with zero‑knowledge proofs. Sidechains give developers a sandbox to experiment with new consensus models, and token bridges keep liquidity flowing across all these networks. Understanding how each piece fits helps you pick the right solution for a specific use case, whether you’re a trader looking for cheap swaps, a developer building a fast game, or an investor assessing risk.

Below you’ll find a curated set of articles that dive deeper into these topics, compare real‑world performance, and show how the latest Ethereum layer 2 projects are shaping the future of crypto. Explore the guides, reviews, and analysis to see which scaling option matches your needs.