GlossaryIntermediate
Consensus Mechanism
The rules a network uses to agree on which transactions and blocks are valid.
A consensus mechanism is the set of rules a blockchain network uses so that many independent participants can agree on a single, shared version of the transaction history, without needing to trust a central authority.
Different networks use different consensus mechanisms, each with its own trade-offs around security, decentralization, energy use, and speed. See Kaavon's "Proof of Work" and "Proof of Stake" glossary definitions for the two most widely used examples, and "Delegated Proof of Stake" for a further variation on one of them.
Examples
- Bitcoin's consensus mechanism is proof of work; Ethereum's is proof of stake.
- A network's consensus mechanism determines who gets to propose the next block and how disputes are resolved.