Consensus (how the network agrees)

Consensus is the rule set a network uses to agree on the next valid block (or ledger version) without a single boss. Different networks use different recipes (for example proof of work, proof of stake, or validator voting) — the shared goal is to make cheating expensive.

A payment that just appeared can still be reorganized on some networks until more blocks (or validations) pile on. Large transfers are safer when you wait for deeper confirmation.

Every network needs a way to pick one official order of transactions, so nobody can spend the same money twice. Different chains solve this differently. In proof of work, computers race to solve a costly puzzle, and the winner adds the next block. In proof of stake, participants lock up coins and can lose them if they cheat.

The XRP Ledger uses a third recipe. Each server picks a list of validators it trusts. The validators share proposals for which transactions go into the next ledger, adjust them over a few rounds until enough of them match, and then confirm they all got the same result.

Real example: when you send XRP, you sign the transaction and your wallet passes it to the network. Validators agree on the set of transactions, the new ledger version closes, usually in about 3 to 5 seconds, and once validated it is final. The small fee is destroyed along the way. If too many validators disagree, the network pauses instead of confirming bad data. Sources: Consensus Protocol, Ledger Close Times.