Proof of Stake (PoS)

Proof of stake uses assets committed to the protocol as the resource for allocating validation responsibilities. Proposer selection and voting weight depend on each network’s rules. PoS designs do not all use the same delegation, penalty or finality system.

Ethereum combines a fork-choice rule with a finality mechanism. Validators propose blocks and issue attestations. Actions such as incompatible signatures can be demonstrated cryptographically and cause slashing; unavailability is handled through different penalties.

Security depends on stake distribution, clients and operators, incentives and participation conditions. A joining node may require a recent trusted checkpoint. Reducing mining work does not eliminate concentration, software failures or governance attacks.