Consensus & validators

NeutronX uses CometBFT, a BFT consensus with instant finality. A block is final as soon as validators holding more than 2/3 of the stake vote for it. There are no rollbacks or forks after that.

How a block is accepted

Proposal. The proposer offers a block. Proposers take turns, and validators with more stake are picked more often.
Prevote. Validators check the block and vote for it.
Precommit. Once more than 2/3 of the stake is reached, validators vote a second time and attach oracle prices to the vote (a vote extension).
Commit. After more than 2/3 of precommits the block is final.

If the proposer misses its timeout, a new round starts with another proposer.

When things go wrong

Situation	What happens
More than 2/3 of stake online	Blocks are produced at the normal pace, ~0.84 s
More than 1/3 of stake offline	The network stops and waits. Nothing is lost: once validators return, block production continues from the same block
An attempt to create a conflicting block	Only possible if at least 1/3 of the stake signs double votes. Such votes are provable and punished

Validators

Weight. Voting weight equals the validator's stake: its own and delegated. The active set holds up to 60 validators.
Duties:
- sign blocks;
- publish oracle prices through vote extensions in every block.
Commission:
- from 5% to 20%;
- it can change by no more than 1% per day.
How to delegate NTX is covered in Staking.

Penalties

Violation	Penalty
Double signing	Slash of 5% of stake and permanent removal from the set
Downtime: fewer than 5% of the last 10,000 blocks signed	Slash of 1% of stake, jail for 10 minutes
Oracle price more than 5% away from the median	Slash of 0.01% of stake, at most once per block. 3 violations within 1,000 blocks mean jail if the set has at least 5 validators

A slash reduces the validator's whole stake, delegations included. A jailed validator does not sign blocks or earn rewards until it sends MsgUnjail after the term ends.