What is Proof of Stake?

How do thousands of computers agree on who paid whom, without a bank in the middle? In Proof of Stake, agreement rests on participants who put up their own cryptocurrency as collateral. This commitment is called staking, and it ties the network’s security to an economic incentive: anyone who breaks the rules can pay a price.

Think of a cooperative where those who take on the job of checking the shared fund put down a deposit. If they do their job properly, they get paid. If they try to falsify the books, they risk losing the deposit. The analogy doesn’t cover every technical detail, but it captures the basic logic.

On the network, this job is done by validators. The protocol selects who will propose the next block, and the others check or vote according to its rules. The amount staked often affects the weight or likelihood of participation, but exactly how varies by blockchain. Rewards can come from newly issued coins, transaction fees or a combination of the two.

Why it matters

Unlike Proof of Work, PoS doesn’t require competitive mining with constant computation. As a result, it has much lower energy requirements. That alone doesn’t guarantee cheap transactions, high speed or decentralization; those also depend on the rest of the network’s design.

For us, a key question is who controls participation in validation. If a large share of the stake is concentrated among a few providers, significant influence may be concentrated too. Depending on the network, a holder can take part as a validator or delegate their stake to someone else.

What to watch out for

Staking rewards are not guaranteed bank interest. The coin’s price can fall, and there may be waiting periods to unlock it. On some networks, certain violations result in slashing, a cut to the staked collateral. Going offline temporarily can also cost rewards or bring other penalties, depending on the rules.

If you use an exchange or a staking service, the provider’s risks are added on top. And a service advertising “yield” doesn’t necessarily take part in Proof of Stake: it may be lending out your coins or using them in other ways.