BFTree — Scaling HotStuff to Millions of Validators
summary
System designs a virtual tree of validators that aggregates BLS signatures up from leaves so a block can finalize with a single constant-size signature; HotStuff is the underlying protocol, worst-case requires O(log n) rounds and overall O(n log n) messages. A per-validator public key cache stores intermediate aggregated keys so verifying a million-node signature avoids a multi-minute cost. Repositioning validators left/right builds a reputation so a branching factor 32 tree reaches ~2s best-case consensus for ~1,000,000 nodes; adversaries that reshuffle malicious nodes every block break the gain.
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chapters (8)
- 0:00Introduction
- 2:15Limitations of current BFT
- 4:42VF-tree design and approach
- 8:06Handling disagreement
- 12:37Protocol enhancements
- 16:19Verification and challenges
- 20:50Performance and analysis
- 29:41Conclusion and Celo overview
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