Validium
A validium processes transactions off-chain with ZK validity proofs but keeps the data off Ethereum — with a committee or operator instead. Same fast final
A validium processes transactions off-chain with ZK validity proofs but keeps the data off Ethereum — with a committee or operator instead. Same fast finality as a ZK rollup, far cheaper data costs, and a weaker trust promise: if data holders vanish, your funds can freeze even though nobody can steal them.
Why it matters
Validiums sit between rollups and sidechains on the security spectrum — cryptographically honest, data-hostage-able. Fine for gaming and high-volume low-value use; questionable for life savings. Always ask where the data lives, because “validity-proven” answers a different question than “exit-able.”