Consensus Algorithms
How distributed nodes agree on a single source of truth without trusting each other. From Paxos to Raft to PBFT — the recipes that keep systems consistent under failure.
Paxos
The classic. Proposers, acceptors, learners. Hard to implement correctly but foundational to every consensus system built since.
Raft
Designed for understandability. Leader election, log replication, safety. Powers etcd, Consul, and countless production clusters.
PBFT
Practical Byzantine Fault Tolerance. Tolerates malicious nodes, not just crashes. The backbone of permissioned blockchain networks.
Nakamoto
Proof-of-work consensus without identities. Longest chain wins. Bitcoin's breakthrough — probabilistic finality at global scale.
Choosing the right recipe
Crash fault only? Raft or Paxos. Raft if your team values debuggability. Paxos if you need multi-paxos for geo-distribution.
Byzantine actors? PBFT for small (<100) known validators. Tendermint for BFT with rotating validator sets. Nakamoto for open participation.
Performance sensitive? Leader-based protocols (Raft, Multi-Paxos) handle high throughput. BFT variants add rounds — expect 2-3x latency overhead.
Ready to dive deeper?
Explore our distributed locks recipe for practical consensus patterns in production.