Ostracon: Challenge Consistency of Blockchain in P2P Network

Torao Takami
LINE / Blockchain Engineering Team / Senior Software Engineer

https://linedevday.linecorp.com/2021/ja/sessions/7
https://linedevday.linecorp.com/2021/en/sessions/7
https://linedevday.linecorp.com/2021/ko/sessions/7

Transcript

2. Do you think how many years will your living record be lost? あなたの生きた記録は 何年後に消えると思いますか?
3. Save your record How do historical documents survive? One model is…
4. Peer-to-Peer Network The potential for personal scale geo-distributed disaster resilience
5. Bitcoin
6. Ownership Traceability Cryptocurrency Vaccination Metaverse How Your Social Application? Your business, service, or career? Audit
7. Consistency Model Consistency Typical Mechanisms Implementations Sequential 1BYPT
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8. Consistency Model Consistency Typical Mechanisms Implementations Sequential #'5
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9. What about Blockchain? Difficulties with non-deterministic network P2P Network 1. Byzantine failure must be considered. 2. Participants can be free to join and leave (not fixed). Cloud or On-Premise DB 1. Assuming to be up to Crash-Recovery failure. 2. The network is well managed.
10. Consistency Model Consistency Typical Mechanisms Implementations Sequential #'5
    7PUJOH )ZQFSMFEHFS
    'BCMJD
    5FOEFSNJOU /&.
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    ;JMMJRB Causal %"(CBTFE *05"
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11. Consistency Model Consistency Typical Mechanisms Implementations Sequential #'5
    7PUJOH )ZQFSMFEHFS
    'BCMJD
    5FOEFSNJOU /&.
    530/
    ;JMMJRB Causal %"(CBTFE *05"
    #ZUFCBMM Probabilistic 1P8
    -POHFTU
    )JTUPSZ
    8JOT #JUDPJO
    &UIFSFVN Sequential Causal (client-centric) for Byzantine Tolerance or P2P Network Probabilistic
12. Consistency Model Consistency Typical Mechanisms Implementations Sequential #'5
    7PUJOH )ZQFSMFEHFS
    'BCMJD
    5FOEFSNJOU /&.
    530/
    ;JMMJRB Causal %"(CBTFE *05"
    #ZUFCBMM Probabilistic 1P8
    -POHFTU
    )JTUPSZ
    8JOT #JUDPJO
    &UIFSFVN Sequential Causal (client-centric) for Byzantine Tolerance or P2P Network Probabilistic
13. Consistency Model Consistency Typical Mechanisms Implementations Sequential #'5
    7PUJOH )ZQFSMFEHFS
    'BCMJD
    5FOEFSNJOU /&.
    530/
    ;JMMJRB Causal %"(CBTFE *05"
    #ZUFCBMM Probabilistic 1P8
    -POHFTU
    )JTUPSZ
    8JOT #JUDPJO
    &UIFSFVN Sequential Causal (client-centric) for Byzantine Tolerance or P2P Network Probabilistic
14. CAP Theorem for Distributed Database and Byzantine Tolerance or P2P Network Probabilistic Consistency Eventual Consistency Causal Consistency Sequential Consistency $ " 1 vailability onsistency artition Tolerance Non-deterministic Deterministic
15. LINE Blockchain What should we choose? https://blockchain.line.me
16. Ostracon It’s network and tiered structure - Use-Cases: - Finance, Commerce, Logistics, Medicine, Industries, and others - Requirements: - Strong Consistency - Cryptographic Security - Interoperability - Resilience Ostracon WASM VM Node LINE Blockchain Mainnet Smart Contract Client Other Blockchain Network
17. Byzantine Fault-Tolerance Protect safety and liveness from malicious behavior BFT Variants - pBFT - LFT2 - Honey Badger BFT - BFT-SMaRt - Tendermint-BFT - HotStuff BFT - Finality Gadget (Ethereum 2) - etc. prevote precommit commit propose
18. + Improvements in performance and election of committee Verifiable Random Function - Fast Processing - Cryptographically Secure PRNG - Public and Formal (IRTF Draft) → Unpredictable Property BLS Signature Aggregation - Time and Space Complexities O(n) → O(1) - Public and Formal (IRTF Draft)
19. The Sprit of the Future Our three technical challenges Distributed Technology Agreement BFT Economics Game Theory Election PoS+VRF Cryptography Performance Signature Aggregation BLS
20. https://github.com/line/ostracon Thank you