How Do “Finality Gadgets” in PoS Systems Serve a Similar Function to Checkpoints?
Finality gadgets in Proof-of-Stake (PoS) systems serve a similar function to checkpoints by providing an explicit, deterministic mechanism to finalize blocks. They typically use a supermajority (e.g.
2/3rds) of validators to attest that a block is irreversible. Unlike the probabilistic finality of PoW checkpoints, which are often developer-set, the finality gadget is a built-in protocol feature that ensures that once a block is finalized, it cannot be reverted without the slashing of a massive amount of staked capital, providing a strong, cryptographically-enforced guarantee of finality.
Glossar
PoS Systems
Consensus ⎊ Proof-of-Stake systems represent a class of blockchain consensus mechanisms where block creation and validation are determined by the quantity of cryptocurrency a participant holds and is willing to ‘stake’ as collateral against malicious behavior.
Probabilistic Finality
Certainty ⎊ Probabilistic finality within cryptocurrency and derivatives represents a quantified assessment of settlement irreversibility, diverging from traditional absolute finality models.
Checkpoints
Checkpoint ⎊ In the Ethereum Proof-of-Stake architecture, checkpoints are specific blocks that mark a point of finality on the Beacon Chain.