CHURP: Dynamic-Committee Proactive Secret Sharing

on YouTube ↗30m

" summary

CHURP uses bivariate polynomials and a dimension‑switch trick to raise the threshold during committee handoffs, adds zero polynomials to refresh shares, and posts compact KZG commitments on a blockchain to detect bad shares. Implementation is ~2,000 lines, runs on 100‑node geo tests, and reports a 2000× off‑chain reduction versus prior work and median handoff latency ~5s (LAN) vs 12s for the comparator.

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" chapters (12)

1. 0:00Introduction to Chirp
2. 1:12Motivation and background
3. 2:55Secret sharing foundations
4. 7:11Proactive secret sharing
5. 8:33Addressing committee handoffs
6. 10:47Blockchain as a communication
7. 12:43Dimension switching logic
8. 15:38Updating secret shares
9. 17:30Security and commitment
10. 21:35Performance comparison
11. 24:20Implementation and results
12. 26:43Conclusion and Q&A

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