ブロックチェーンと金融システム / Blockchain and Financial Systems

2021年12月14日(火)、東京大学およびオンラインにて開催された 近未来金融システム創造プログラム – 第13回 金融と技術 (各論IV) にて使用したスライドです。

1. Replicate the logs. – 13 ( IV) ks91@sfc.wide.ad.jp / ks91@aoni.waseda.jp — 2020-12-14 – p.1/40
2. https://speakerdeck.com/ks91 — 2020-12-14 – p.2/40
3. ( ) SFC ( ) CSO (Chief Science Officer) 1993 ( ) 2006 ( ) SFC 21 P2P (Peer-to-Peer) 2011 2018 2019 VR 2021.7 VR 2021.8 “ALL THESE WORLDS ARE YOURS” VR 2021.9 & VR 2021.12 ( (VR) ) → ( ) — 2020-12-14 – p.3/40
4. (1) 2020 9 60 (2020) : ( ) . . . = ( ) GitHub Copilot (AI ) — 2020-12-14 – p.4/40
5. (2) (2020) : ( ) ( = + ) — 2020-12-14 – p.5/40
6. — 2020-12-14 – p.6/40
7. SAY NO TO BULLSHIT JOBS David Graeber, “Bullshit Jobs: A Theory” (2018) ← (4 ) ( ) ( ) — 2020-12-14 – p.7/40
8. Alexa, ত࿨࣌୅
   
    ੈلޙ൒ ࣾձγεςϜ ࣾձ؀ڥ ػց ٕज़ ਓؒ ࣗಈγεςϜ ྩ࿨࣌୅
   
    ੈلલ൒ ిؾ͚ͭͯ ͸͍ ͸͍ ిؾ͚ͭͯ ͜ͷ৚݅ͷͱ͖ ٕज़Ͱ͋Γࣾձ؀ڥ
   ˠ
   ࣗવ؀ڥ ਓ ⇒ ( ) — 2020-12-14 – p.8/40
9. (4 ) (DX ) ( ) — 2020-12-14 – p.9/40
10. SF SF → VR 2021.7 — 2020-12-14 – p.10/40
11. VR (1) 50m — 2020-12-14 – p.11/40
12. VR (2) . . . — 2020-12-14 – p.12/40
13. VR (3) . . . 2030 — 2020-12-14 – p.13/40
14. ( ) ⇒ ( ) — 2020-12-14 – p.14/40
15. — 2020-12-14 – p.15/40
16. ( ) ( ) (BP : Blockchain Property ) BP-1 : ( ) BP-2 : ( , ) BP-3 : ( ) ( ) ( ) — 2020-12-14 – p.16/40
17. ( ) ( ) ( ) ( ) ( 16 ) SHA (Secure Hash Algorithm) ( ) 1bit — 2020-12-14 – p.17/40
18. ( ) ( ) < , > ( ) : < , > : : < , , > : OK NG — 2020-12-14 – p.18/40
19. BP-1 ( ), BP-2 ( ) BBc-1 f : → BP-3 ( ) ( ) ( ) ← BP-2 ← BP-3 ( ) ( ) ← BP-3 + ← BP-{1,2} — 2020-12-14 – p.19/40
20. [Lamport 1984][Schneider 1990] (1) (2) (3) (4) ( ) ← ↑ — 2020-12-14 – p.20/40
21. ( 4 TX ) SMRP (State Machine Replication Problem) SMRP-1 ( ) SMRP-2 : ← — 2020-12-14 – p.21/40
22. ( ) ( ) ϒϩοΫ൪߸
    
    O ϒϩοΫ൪߸
    
    O  ϒϩοΫ൪߸
    
    O  ϒϩοΫ൪߸
    
    O  ϒϩοΫ൪߸
    
    O  ϒϩοΫ൪߸
    
    O  ϒϩοΫ൪߸
    
    O  ϒϩοΫ൪߸
    
    O  ͍ͪ͹Μه࿥ɾॻ͖׵͑ͷίετ͕ߴ͍ྺ࢙ ࠷΋վ͟Μ͠ʹ͍͘ྺ࢙ ͕༗ޮ ͻͱͭखલͷϒϩοΫͷ ʮμΠδΣετʯ σδλϧॺ໊͞Εͨ ʮτϥϯβΫγϣϯ औҾ ʯ ϒϩοΫΛ࡞ΔͨΊʹ͸ɺͦͷʮμΠδΣετʯ͕͋Δ਺ҎԼͱ͍͏৚݅Λຬͨͨ͠Γ 1SPPG
    PG
    8PSL Ծ૝௨՟ͷ࣋ͪ෼ʹԠͨ͡ݖརΛ࢖ͬͨ౤ථͰউͬͨΓ 1SPPG
    PG
    4UBLF ͢Δඞཁ͕͋Δ ίετ͕͔͔Δ ϒϩοΫΛ࡞Δਓ͸ͦͷதʹࣗ෼ʹѼͯͨ Ծ૝௨՟ͰͷใुΛॻ͖ࠐΉ͜ͱ͕Ͱ͖ɺ ͦͷϒϩοΫ͕༗ޮͳྺ࢙ͷதʹ͋Δ৔߹ʹ ݶΓใु΋༗ޮͱͳΔ τϥϯβΫγϣϯͷଘࡏΛ֬ೝ͢Δ ͨΊͷޮ཰తͳํ๏͕ఏڙ͞ΕΔ ਖ਼౰ੑ ଘࡏੑ །Ұੑ Proof of Work ( ) . . . → — 2020-12-14 – p.22/40
23. (BP-3 ) ( : ) (BP-3 ) ( : ) (← NFT ) BP-{1,2,3} BP-{1, 2} ⇒ (← ) — 2020-12-14 – p.23/40
24. (DeFi) (DeFi : Decentralized Finance) ⇒ ( ) ⇒ ( ) ⇒ ( ) ( ) NFT (Non-Fungible Token) NFT ( NFT ) — 2020-12-14 – p.24/40
25. . . . 2009 ↑ 11 . . . — 2020-12-14 – p.25/40
26. BBc-1/Ethereum API/ https://github.com/beyond-blockchain/examples/tree/master/certify-web 1. ID ( ) 2. ID ID . . . ID ( ) — 2020-12-14 – p.26/40
27. ID { "id": "4445 4558 1689", "name": "Wednesday Addams", "born": "1980-02-12", "address": "0001 Cemetery Lane", "public-key": "04d49e0786a37efce8552d6fd1566d7cfd86f110d4d95f1...4edb", "algo": "ecdsa-p256v1", "sig": "609b390f9486110d1ba39fc59cc46f1c2aa31ae8e40d3454c05a42...48e2", "pubkey": "0479c6676de61b41b7d0291b338f3279671d649f0a71bbb495...4bd1", } (Merkle) Ethereum — 2020-12-14 – p.27/40
28. *%
    Χʔυจॻ JE
    
    JE OBNF8FEOFTEBZ
    "EEBNTOBNF 8FEOFTEBZ
    "EEBNT ͷ΋ͷ ࣏ࣗମͷ΋ͷ CPSOCPSO BEESFTT
    $FNFUFSZ
    -BOFBEESFTT QVCMJDLFZEFDFECQVCMJDLFZ *% Χʔυจॻ ͷμΠδΣετ ॺ໊෇͖ *% Χʔυจॻ ͷμΠδΣετ ࿈͔݁ͯ͠Β ܭࢉ͢Δ ॺ໊Λݕূ͠ɺ ੒ޭͨ͠Β ࿈͔݁ͯ͠Β ܭࢉ͢Δ EJHFTU EJHFTU EJHFTU BMHPSJUIN TJHOBUVSF QVCMJD
    LFZ EJHFTU EJHFTU EJHFTU EJHFTU
    +40/ σʔλߏ଄͸ɺ಺෦ॲཧͰ͸ 9.- ʹม׵͞Ε·͢
    ΋ͱ΋ͱ 9.- ༻ʹ࡞ͬͯ͋ΔϥΠϒϥϦΛ࢖༻͍ͯ͠·͢ ɻ
    ෦෼తʹӅ͞Ε͍ͯͯ΋ূ໌Ͱ͖ΔΑ͏ʹɺηΫγϣϯ͝ͱʹμΠδΣετΛܭࢉ͍ͯ͠·͢ɻ
    ྫ͑͹ɺ*% ΧʔυͰ೥ྸ΍ॅॴɺ͋Δ͍͸ެ։伴Λ֬ೝ͢Δ͚ͩͰ͋Ε͹ɺ*% ൪߸ΛݟΔ͜ͱ͕๏཯Ͱېࢭ͞Ε͍ͯΔ౳ͷ৔߹ɺ
    
    *% ൪߸ΛӅͯ͠ ͦͷ෦෼ΛରԠ͢ΔμΠδΣετͰஔ͖׵͑ͯ ఏࣔͯ͠΋࠷ऴతʹॺ໊෇͖ *% Χʔυจॻͷಉ͡μΠδΣετΛܭࢉͰ͖ΔͷͰɺଘࡏূ໌͕Ͱ͖·͢ɻ
    ʮμΠδΣετʯͱ͸ɺ҉߸ֶతϋογϡؔ਺ʢࠓճ͸ 4)"
    ʣʹΑͬͯܭࢉ͞Εͨ஋ͷ͜ͱͰ͢ɻ
    Θ͔ͣ  ϏοτͰ΋ݩͷσʔλ͕ҟͳΔͱɺฦͬͯ͘Δ஋͕શ͘ҟͳΓɺμΠδΣετ͔ΒݩͷσʔλΛ
    ਪଌ͢Δ͜ͱ͸Ͱ͖·ͤΜɻ — 2020-12-14 – p.28/40
29. API/ Merkle Proof จ
    
    ॻ  จ
    
    ॻ  จ
    
    ॻ  จ ॻ  จ
    
    ॻ O μΠδΣετ μΠδΣετ μΠδΣετ μΠδΣετ μΠδΣετ μΠδΣετ μΠδΣετ ح਺ͷ৔߹͸ ෳ੡͢Δ ɾจॻ 
    Λಘͨ
    " ࢯ͸ɺಉ࣌ʹূ໌ཁૉͱͯ͠ɺϒϧʔͰࣔ͞ΕΔμΠδΣετͱ֤ʑ͕ࠨӈͷͲͪΒʹҐஔ͢Δ͔Λड͚औΔɻ ɾ" ࢯ͸จॻ  ͷμΠδΣετ͔Β࢝Ίͯɺ࿈݁͢΂͖Ұ࿈ͷμΠδΣετΛ஌Δ͜ͱʹͳΔͷͰɺϚʔΫϧϧʔτʹࢸΔ·Ͱͷ ɹܭࢉΛ࠶ݱͰ͖ɺಘΒΕͨϚʔΫϧϧʔτ͕ &UIFSFVN εϚʔτίϯτϥΫτʹه࿥͞Ε͍ͯΔ஋ͱҰக͢Δ͜ͱΛ֬ೝͰ͖Δɻ ɾͦͷܭࢉΛ୅ߦ͢Δͷ͕
    DFSUJGZXFC
    ͷαʔϏε
    ݪཧͷཧղͱඞཁͳ৘ใ͕͋Ε͹୭Ͱ΋࠶ݱͰ͖Δ  ূ໌͞ΕΔ ɻ ه࿥͢Δ ಡΈग़ͤΔ ূ໌Λ ඞཁͱ͢Δऀʹ ։ࣔ͞ΕΔ৘ใ ˞
    ##D
    ͸ɺ͜ͷߏ଄Λอଘ ɹ
    ͍ͯ͠Δ͕ɺαϒπϦʔΛ ɹ
    ূ໌ཁૉԽͯ͠౉ͨ͠ޙ͸ɺ ɹ
    ূ໌͢Δ্Ͱ͸
    ##D ͸ෆཁ ެ։͞ΕΔ৘ใ ϚʔΫϧϧʔτ Ϛ ồ Ϋ ϧ ໦
    γ ε ς Ϝ ͕ อ ؅ ͠ ֤ Ϣ ồ β ʹ ෦ ෼ త ʹ ఻ ͑ Δ ʜʜ ʜʜ ʜʜ ʜʜ ʜʜ μΠδΣετ μΠδΣετ μΠδΣετ μΠδΣετ μΠδΣετ μΠδΣετ &UIFSFVN
    ϒϩοΫνΣʔϯ ʜ ʜ ##D
    ϥΠϒϥϦ
    ূ໌ॻΞϓϦͰ࣮ݱ — 2020-12-14 – p.29/40
30. Merkle Proof ( ) { "proof": { "spec": { "subsystem": "ethereum", "network": "ropsten", "contract": "BBcAnchor", "contract_address": "0x609CD0aF4663bbA6c7105fd34BbCBCDd5e75067C", "block": 9186681 }, "subtree": [ { "position": "right", "digest": "bd7d8c62a483e23b8e4713699bec9ff036ead7f3a72a8ff70684cdec1e8b6aeb" }, : # ] } } — 2020-12-14 – p.30/40
31. BBcAnchor.sol ( ) contract BBcAnchor { mapping (uint256 => uint) public _digests; constructor () public { } function getStored(uint256 digest) public view returns (uint block_no) { return (_digests[digest]); } function isStored(uint256 digest) public view returns (bool isStored) { return (_digests[digest] > 0); } function store(uint256 digest) public returns (bool isAlreadyStored) { bool isRes = _digests[digest] > 0; if (!isRes) { _digests[digest] = block.number; } return (isRes); } } / — 2020-12-14 – p.31/40
32. τʔΫϯ ୅ସ՟ฎ εϚʔτίϯτϥΫτ ݕূՄೳͳঢ়ଶϚγϯ ϓϩϏφϯε དྷྺূ໌
    ୅ସՄೳ ঈؐෆೳ ୅ସՄೳ ঈؐՄೳ ୅ସෆೳ ঈؐՄೳ ୅ସෆೳ ঈؐෆೳ ূ໌͢Δ ಉఆ͢Δ ࢧ෷͍౳ ࠷ॳͷԠ༻ *%
    Χʔυ౳ ηΩϡϦςΟ τʔΫϯ ূ݊ ౳ ηϯαʔ౳ ෺ྲྀɾ Ҩݴॻ౳ อݥਃ੥౳ ௥੻͢Δ ײ஌͢Δ தԝۜߦ σδλϧ௨՟౳ ҭ੒ήʔϜ౳ ൿີ伴Λ࢖͑Δ͔Βຊਓʁ ෛ࠴  Ξηοτͷ ਺஋දݱΛҠసͰ͖Δʁ ొ࿥͞Εͨίʔυͱ ͦͷ࣮ߦϩάͱ݁Ռͷ ਅਖ਼ੑΛ୲อͰ͖Δʁ ݖҖ͕
    Կ͔ͷ಺༰Λূ໌͢Δʁ ࣋ଓ͢Δଘࡏʹ͍ͭͯ ه࿥ΛΞοϓσʔτՄʁ ओମ͕͍ͳ͘ͳͬͯ΋ աڈͷσʔλ͸༗ޮʁ Ұൠతͳ ೝࣝ ػೳͷ ෼ੳ݁Ռ — 2020-12-14 – p.32/40
33. ( ) — 2020-12-14 – p.33/40
34. IP (Internet Protocol) ( ) : IP : / (IP ) : : — 2020-12-14 – p.34/40
35. : ⇒ LINE → → ( ) ( ) ⇒ → → → — 2020-12-14 – p.35/40
36. ( ) . . . ( : ) (GitHub ← D.C. ) ( : ) ↑ P2P ( : Ethereum) ( ) — 2020-12-14 – p.36/40
37. ( ) ( ) . . . ← ( ) . . . — 2020-12-14 – p.37/40
38. ( ) (cyborg) = (cybernetic) (organism) 1 : ← 2 : ⇒ (1) (2) ⇒ ← — 2020-12-14 – p.38/40
39. ࠃʹΑΔ ҆શอো ՟ฎ ࢢ৔ ෼ۀࣾձ ઐ໳ੑͷ ෼Խ ࢧ ࣋ ࢧ ࣋ ࢧ࣋ %9 ۚ༥ ൃߦ ೲ੫ ࣗಈԽɾޮ཰ԽɾຽओԽ ࣗಈԽɾ ޮ཰Խɾ ຽओԽ ࣗಈԽɾ ޮ཰Խɾ ຽओԽ ઐ໳ະ෼Խ΁ʂ — 2020-12-14 – p.39/40
40. 100 50 ( 50 ) ( ) . . . — 2020-12-14 – p.40/40