Flexible Byzantine Fault Tolerance

on YouTube ↗36m

" summary

Claims a single consensus design that lets different clients pick their own timing and fault assumptions while increasing total tolerated faults by adding a new fault class alive but corrupt (ABC) that only attacks safety. Builds a synchronous protocol using network-speed replicas that are delta-agnostic and commit after 2Δ with no observed equivocation, a view-change that mandates certificates (F+1 statuses) to preserve safety, and a quorum theory called flexible Byzantine quorums that maps which (Byzantine, total) fault pairs each client can safely accept.

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" chapters (20)

1. 0:00Intro
2. 0:36Flexible Byzantine Fault Tolerance a new approach to designing BFT solutions
3. 2:10Classical Consensus Protocols in State Machine Replication
4. 3:49Classical Approach to Consensus Protocols
5. 5:04Optimized for Byzantine Faults
6. 6:06Administrator makes All Assumptions
7. 6:44No Recovery
8. 7:05Introduce alive-but-corrupt Faults
9. 7:46Support Client Diversity
10. 9:19Support Client Recovery
11. 9:38Flexible BFT: Safety, Liveness, and Learners Classical consensus protocols
12. 14:50Flexible BFT: Key Technical Contributions
13. 17:22Sync BFT Protocol with Network Speed Replicas
14. 18:53Synchronous BFT Protocol: Assumptions
15. 19:39A First Attempt
16. 21:03Why Does 24 Wait After Vote Suffice to Commit?
17. 23:18Tolerating Malicious Leaders
18. 24:00View Change, i.e., Change Leader
19. 27:18Flexible Byzantine Quorums
20. 31:11Comparison with Related Work

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