Crosslink and Possible Futures of Proof-of-Stake in Zcash

on YouTube ↗01h 02m

" summary

Proposal claims Crosslink 2 gives deterministic finality by layering a stake-weighted BFT over the existing PoW chain, requiring a one‑third adversary bound and Sigma confirmations so finalized blocks sit about double current confirmation depth (roughly 20 blocks if current is 10). Security proofs fit on a few slides and safety holds under either best‑chain or BFT assumptions. Tools: simulator in Python (Simpy, PR mostly complete). Prototype: Zebra prototype planned, not for zcashd.

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" chapters (32)

1. 0:00Intro
2. 0:45Acknowledgements
3. 1:07What is a black chain?
4. 3:10Open Economic Computation
5. 4:54Why Proof-of-Stake, then?
6. 8:31Why Hybrid PoW/Pos as a first step?
7. 11:25Goals and Requirements - Uses Cases
8. 13:37Q?: Will PoS impact ZEC?
9. 13:57Q?: Crosslink a PoW alternative for other blockchains?
10. 15:36Q?: Opinion on Etherum’s Whisk?
11. 16:18Goals and Requirements - Stability/Security
12. 19:03ECC’s Proposed Design
13. 21:27Q?: Why focus on this?
14. 22:45Simplified Motivation for Crosslink
15. 25:20Crosslink
16. 27:54What is a BFT protocol?
17. 32:09Why do we need a BFT protocol?
18. 34:17Security and Performance Goals of Crosslink
19. 39:00Bounded Availability and Safety Mode
20. 41:17Why retain Zcash’s PoW for now?
21. 42:32Brief background on stake-weighted BFT
22. 45:24Crosslink 2
23. 46:37Q?: Crosslink paper?
24. 47:15How does Crosslink 2* work?
25. 53:33Security Assumptions
26. 54:45Security Theorems for Log(fin)
27. 56:01What’s Next?
28. 57:30Q?: Zcashd/Zebrad Proof of Concept Status??
29. 58:02Zebra Prototype
30. 58:30Open design issues
31. 59:54Plan to Prototype on Transient Testnests
32. 1:00:42How to contribute?

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