Consensus mechanism is the set of technical rules that determines how participants in a distributed network agree on the valid chain and blockchain state.

It defines questions such as who can propose blocks, how other participants validate them, which chain is accepted, and what economic or computational conditions protect the network from invalid history.

Examples

  • Proof-of-Work — security is linked to computational work.
  • Proof-of-Stake — participation in block validation is linked to staking and economic security.
  • Other mechanisms can use different rules for block production, validation, and participant incentives.

The consensus mechanism affects hardware requirements, confirmation behavior, energy use, participation economics, and the security model of a blockchain. Therefore, the same terminology can describe technically different systems across networks.