Era

Definition

Era: A (whole) number of epochs, which is the period that the validator set (and each validator's active nominator set) is recalculated and where rewards are paid out

Description

1 block - 6 sec 1 epoch - 2400 blocks - 4 hour 1 era - 6 epoch - 24 hours

There are some cases related to era’s usage: Reward payout

Reward payout

• Payments occur at the end of every era.

• Rewards are recorded per epoch and calculated per era.

• In order to be paid your staking rewards, someone must claim them for each validator that you delegate. Stakers claim their rewards for past eras by submitting a transaction with a validator ID and an era index. This naturally leads to spreading out reward distribution, as people make transactions at disparate times, rather than updating the accounts of all stakes in a single block.

• Even if everyone submitted a reward claim at the same time, the fact that they are individual transactions would allow the block construction algorithm to process only a limited number per block and ensure that the network maintains a constant block time.