Byzantine fault tolerance conceptpaper
Stronger fault model than crash-fault tolerance: nodes may behave arbitrarily badly — lie, equivocate, send conflicting messages to different peers.
Stronger fault model than crash-fault tolerance: nodes may behave arbitrarily badly — lie, equivocate, send conflicting messages to different peers. Harder to tolerate (need 3f+1 nodes to handle f Byzantine faults, vs 2f+1 for crash-only). Most production systems assume crash-fault and operate inside trust boundaries; BFT matters in trustless settings: blockchains, multi-organization consensus, safety-critical systems where compromised hardware is a real threat.