Validator
What is a blockchain validator?
A node that proposes and attests to new blocks in a proof-of-stake network. Requires staking capital; misbehavior triggers slashing. In Ethereum, 32 ETH minimum to run a validator; the Pectra upgrade (May 2025) raised the maximum effective balance to 2,048 ETH, enabling validator consolidation. Validator concentration among large staking pools is an ongoing decentralization concern.