The Skip Ratchet

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" summary

Introduces a concrete construction—the Skip Ratchet—that combines hierarchical hashing and skip lists to give group key agreement properties suited to decentralized trustless settings: logarithmic-time seeks across billions of writes, backward secrecy when members join, and efficient resynchronization for long-offline clients. Multiple production implementations exist (TypeScript, Rust, Go, plus private Haskell and Elixir ports) and the design is already driving a decentralized, encrypted file system (WebNative File System) and local-first collaborative data science tooling, with real-world micropayment and payment-channel use cases.

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" chapters (17)

1. 0:00Start
2. 1:38Uses
3. 3:39Deterministic Keys in WNFS
4. 5:15Hash Chains
5. 5:55Pseudoradom Stream
6. 9:58The Ishango Bone
7. 12:52Positional Systems
8. 13:51Mixed-Radix
9. 14:56Compound Hash
10. 16:11Deterministic Skip List
11. 17:00Simplified Binary Skip Ratchet
12. 18:57Deriving Secrets With Secrets
13. 19:40Zeroing & Epochs
14. 21:10Setup
15. 24:01Limiting Ranges
16. 24:58Range Access
17. 25:50Takeaways

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