Layer 2
Last updated 17 October 2026Last verified 17 October 2026
What is a Layer 2 blockchain?
A scaling solution built on top of a base chain (Layer 1) that posts data or proofs back to it for security. Rollups are the dominant L2 architecture: they reduce fees while inheriting Ethereum's security. The sequencer running most L2s is still centralized, which creates a censorship assumption most users overlook. See: Why blockchain infrastructure matters for AI.
TradFi equivalentAn execution venue that settles through the base chain, the way a trading venue settles through a depository it does not own. The operator that orders the trades is usually a single firm, so an L2 carries censorship and liveness risk the base chain does not.