Fault tolerance

Single Notary

A single-node notary service that persists notarization requests in the network.

Raft

When using Raft deployed on n nodes, a Corda notary tolerates crashes of any t < n/2 of these nodes. Hence, at least 50% of the nodes must be running for the network to function.

BFT-SMaRt

For BFT-SMaRt to execute correctly, less than a third of all replicas of the service can be faulty at any moment. Hence, the total number of replicas n must be n >= 3f + 1, where f is the maximum number of faulty replicas.