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イーサリアムの技術 / Ethereum Technology

Kenji Saito
September 18, 2019

イーサリアムの技術 / Ethereum Technology

2019年9月18日(水)、ブロックチェーンハブ主催のブロックチェーンアカデミー「イーサリアムの技術」にて使用したスライドです。

Kenji Saito

September 18, 2019
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  1. ΠʔαϦΞϜͷٕज़
    ϒϩοΫνΣʔϯج൫ٕज़ʲϒϩοΫνΣʔϯͷԠ༻ج൫ʳ
    ϒϩοΫνΣʔϯϋϒ Chief Science Officer / ૣҴాେֶ େֶӃܦӦ؅ཧݚڀՊ ڭत
    ੪౻ ݡ࣐
    [email protected]
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.1/30

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  2. ͜ͷεϥΠυ͸
    https://speakerdeck.com/ks91
    ʹஔ͔Ε͍ͯ·͢
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.2/30

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  3. ؆୯ͳࣗݾ঺հ
    ੪౻ ݡ࣐ (͍͞ͱ͏ ͚Μ͡)
    ૣҴాେֶ େֶӃܦӦ؅ཧݚڀՊ ڭत
    ܚጯٛक़େֶ SFC ݚڀॴ ্੮ॴһɾ؀ڥ৘ใֶ෦ ߨࢣ (ඇৗۈ)
    גࣜձࣾϒϩοΫνΣʔϯϋϒ CSO (Chief Science Officer)
    Ұൠࣾஂ๏ਓϏϤϯυϒϩοΫνΣʔϯ ୅දཧࣄ
    Ұൠࣾஂ๏ਓΞΧσϛʔΩϟϯϓ ୅දཧࣄ
    ܦྺ
    1993 ೥ɺίʔωϧେֶΑΓ޻ֶम࢜߸औಘ (ίϯϐϡʔλαΠΤϯε)
    2006 ೥ɺܚጯٛक़େֶΑΓσδλϧ௨՟ͷݚڀͰത࢜߸औಘ (੓ࡦɾϝσΟΞ)
    ܚጯٛक़େֶ େֶӃ ੓ࡦɾϝσΟΞݚڀՊ΍ SFC ݚڀॴʹͯ 19 ೥ؒʹΘͨΓ
    P2P (Peer-to-Peer) ͓Αͼσδλϧ௨՟౳ͷݚڀʹैࣄ
    2011 ೥ՆΑΓ෱ౡͷ͜Ͳ΋ͨͪͷͨΊͷʮΞΧσϛʔΩϟϯϓʯΛ஥ؒΒͱ։࠵
    ࡢՆ͸ SFC ʹͯ ΞΧσϛʔΩϟϯϓ 2018 ՆʮΦοέʔάʔάϧɺ॓୊΍ͬͱ͍ͯʂʯΛ࣮ࢪ
    ࠓՆ΋ SFC ౳Ͱ ΞΧσϛʔΩϟϯϓ 2019 ՆʮੈքΛ࠶ൃ໌ͤΑ ∼ REINVENT THE WORLDʯΛ࣮ࢪ
    → ࢲͷ಄ͷதͰ͸ͭͳ͕͍ͬͯ·͢ (͜Ε͔ΒͷࣾձͷσβΠϯ͸͜Ͳ΋ͨͪͱҰॹʹ)
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.3/30

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  4. ࠓճͷςʔϚ
    ϒϩοΫνΣʔϯʹΑΔΞϓϦέʔγϣϯͷج൫ͱͯ͠։ൃ͞Ε͍ͯΔ
    ΠʔαϦΞϜʹ͍ͭͯ
    ΠʔαϦΞϜԾ૝Ϛγϯ (EVM)
    ֎෦ΞΫλʔ
    ࣗ཯ΦϒδΣΫτͳͲͷ֓೦΍ɺ
    ࣮૷ํࣜͷಛ௃ɺ
    ਐԽͷํ޲
    ͳͲʹ͍ͭͯղઆ͠·͢
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.4/30

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  5. Ethereum ͱ͸ʁ
    Vitalik Buterin, “Ethereum White Paper: A NEXT GENERATION SMART
    CONTRACT & DECENTRALIZED APPLICATION PLATFORM” (Dec. 2013∼)
    ϒϩοΫνΣʔϯٕज़ΛԠ༻
    ฏۉϒϩοΫִؒ໿ 15 ඵΛ໨ඪ
    ͦ͜ʹϓϩάϥϛϯάݴޠ (= νϡʔϦϯά׬શ) ΛࡌͤΔͱ͍͏ΞΠσΞ
    νϡʔϦϯά׬શ = ສೳνϡʔϦϯάϚγϯΛΤϛϡϨʔτͰ͖Δ
    = ϥϯμϜΞΫηεͰ͖Δ (ແݶͷ) ϝϞϦͱ CPU ͔ΒͳΔܭࢉػΛΤϛϡϨʔτͰ͖Δ
    ⇒ ࣮ࡍʹ͸ɺॻ͚ΔछྨͷϓϩάϥϜʹ੍ݶ͕͋Δ
    ʮ෼ࢄΞϓϦέʔγϣϯʯͷͨΊͷج൫
    ͨͩ͠ػೳ෼ࢄ͢ΔΘ͚Ͱ͸ͳ͘ɺෳ੡ͳͷͰɺ
    ʮDAppsʯͱݺΜͰ͠·ͬͨํ͕ଥ౰
    DApps = ୤தԝ / தԝࣗಈԽ ΞϓϦ
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.5/30

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  6. ϒϩοΫνΣʔϯͱঢ়ଶભҠ
    ϒϩοΫνΣʔϯ = ঢ়ଶϚγϯ (ঢ়ଶભҠγεςϜ) ͷ run = ίϯϐϡʔλͷಈ࡞
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.6/30

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  7. ༻ޠମܥ
    Ether
    Ethereum ʹ͓͚Δ௨՟
    ֎෦ΞΫλʔ
    σδλϧॺ໊Ͱ͖Δ࣮ࡏͰɺΞΧ΢ϯτΛ΋ͭ
    EOA : Externally-Owned Account
    ࣗ཯ΦϒδΣΫτ (಺෦ΞΫλʔ)
    γεςϜ಺Ͱࣗ཯ಈ࡞͠ɺΞΧ΢ϯτΛ΋ͭ
    ͱ͸ݴ͏΋ͷͷɺϝοηʔδΛૹΒͳ͍ͱಈ͔ͳ͍ (ͦͯ͠ϚΠφʔ͕ಈ͔͢)
    ΞΧ΢ϯτ
    Ether ࢒ߴΛ΋ͪɺετϨʔδ (ঢ়ଶ) ΍ EVM ίʔυΛ΋ͯΔ
    EVM ίʔυ
    εϚʔτίϯτϥΫτͷϓϩάϥϜ
    εϚʔτίϯτϥΫτ = Ethereum ʹ͓͚ΔԠ༻ϓϩάϥϜ ̸
    = εϚʔτͳܖ໿
    ϒϩοΫνΣʔϯʹॻ͖ࠐ·ΕΔ͜ͱͰਅਖ਼ੑ͕୲อ͞ΕΔ
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.7/30

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  8. EVM : Ethereum Virtual Machine
    ࣗ཯ΦϒδΣΫτ͕ϝοηʔδΛड͚Δͱىಈ͠ɺίϯτϥΫτΛ࣮ߦɺঢ়ଶΛมԽͤ͞Δ
    ࣮ߦεςοϓຖʹ Gas ͷڙڅ͕ඞཁ (ແݶϧʔϓΛආ͚ɺ
    ʮEVM ͷ࣮ߦऀ = ϚΠφʔʯ΁ͷख਺ྉͱͳΔ)
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.8/30

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  9. Ethereum ͷόʔδϣϯ
    Frontier (2015)
    Homestead (2016)
    Metropolis
    Byzantium (2017)
    zkSNARKs (θϩ஌ࣝূ໌) → Zcash on Ethereum (ZoE) ౳
    Constantinople + St.Petersburg (2019) ← ࠓίί
    ޮ཰Խɺঢ়ଶνϟωϧ (for 2nd Layer)ɺProof of Stake ʹ޲͚ͨௐ੔ ౳
    Serenity
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.9/30

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  10. ϒϩοΫνΣʔϯͷ՝୊ͱ Ethereum
    ॾʑͷϒϩοΫνΣʔϯͷ՝୊ʹରͯ͠ɺݱࡏͷϒϩοΫνΣʔϯͷߟ͑ํͷ
    Ԇ௕ͰऔΓ૊Ή
    ͳͷͰʮϏϤϯυϒϩοΫνΣʔϯʯͰ͸ͳ͍
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.10/30

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  11. ϒϩοΫνΣʔϯͷٕज़తͳ՝୊ͷ੔ཧ (࠶ܝ)
    ඇ࣮࣌ؒੑ (֬཰తಈ࡞)
    ൿಗͷࠔ೉ੑ (ສਓ΁ͷݕূՄೳੑͷ୲อ)
    ϫϯωε (෼ࢄ vs. ෳ੡)
    εέʔϥϏϦςΟ͕ͳ͍ (શࢀՃऀʹෳ੡͞ΕΔͳΒεέʔϧ͠ͳ͍)
    ਐԽͷΨόφϯε͕ࠔ೉ (શһ͕ҰؙͱͳΔඞཁ͕͋ΔͳΒมΘΕͳ͍)
    ΠϯηϯςΟϒͷϛεϚον (ج൫ͱԠ༻ͰͷࢀՃಈػͷෆҰக)
    ωΠςΟϒ௨՟ͷՁ஋Ͱࢧ͑ΒΕ͍ͯΔ (๫མ͢Δͱ͢΂ͯͷԠ༻͕ࢭ·Δ)
    ⇒ θϩϕʔεͰઃܭ͠௚ͤ͹ղ͚Δ
    ࣮ࡍʹਐߦதͰ͢ (ྫ : BBc-1)
    ଟ͘ͷ୆ாٕज़͸θϩϕʔεͰߟ͍͑ͯͳ͍ͱ͜Ζ͕໰୊
    ྫ : ࡞ۀূ໌ͷ෇͔ͳ͍ϋογϡνΣʔϯ͸վ͟Μ͠์୊
    ྫ : ʮ৽ฉϞσϧʯͰݴ͑͹ɺۀքࢴ΍ࣾ಺ใʹࡌͤΔΑ͏ͳ͜ͱΛͯ͠΋ଘࡏূ໌ʹͳΒͳ͍
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.11/30

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  12. Ethereum ͸Ͳ͏औΓ૊Ή͔
    ඇ࣮࣌ؒੑ (֬཰తಈ࡞)
    ⇒ τϥϯβΫγϣϯΛϑΝΠφϥΠζ͢Δ࢓૊Έ΁ (Casper; ޙड़)
    ൿಗͷࠔ೉ੑ (ສਓ΁ͷݕূՄೳੑͷ୲อ)
    ⇒ ZoE (Zcash on Ethereum)
    ϫϯωε (෼ࢄ vs. ෳ੡)
    εέʔϥϏϦςΟ͕ͳ͍ (શࢀՃऀʹෳ੡͞ΕΔͳΒεέʔϧ͠ͳ͍)
    ⇒ γϟʔσΟϯάɺPlasma (ޙड़)
    ਐԽͷΨόφϯε͕ࠔ೉ (શһ͕ҰؙͱͳΔඞཁ͕͋ΔͳΒมΘΕͳ͍)
    ⇒ ༏͍͠ಠࡋऀ (ۤস) (Benevolent Dictator For Life (BDFL))
    ΠϯηϯςΟϒͷϛεϚον (ج൫ͱԠ༻ͰͷࢀՃಈػͷෆҰக)
    ωΠςΟϒ௨՟ͷՁ஋Ͱࢧ͑ΒΕ͍ͯΔ (๫མ͢Δͱ͢΂ͯͷԠ༻͕ࢭ·Δ)
    ⇒ ΞϓϦΛ࣮ߦ͍ͨ͠ਓʑ͕ങ͍ࢧ͑Δʁ
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.12/30

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  13. Ethereum ͷٕज़ͷಛ௃
    Proof of Work + φΧϞτɾίϯηϯαε ͔Β
    ચ࿅͞Εͨ Proof of Stake + ߹੍ٞ ΁
    ·ͣ͸ݱঢ়ͷઆ໌͔Β
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.13/30

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  14. ҉߸ֶతϋογϡؔ਺
    ϏοτίΠϯ
    SHA-256 × SHA-256 (ϒϩοΫ/TX μΠδΣετ)
    SHA-256 × RIPEMD-160 (ެ։ݤμΠδΣετ = ΞυϨεͷݩσʔλ)
    ೋॏʹద༻͢Δ͜ͱͷҙຯ (1 ஈ໨͕িಥͨ͠Βʁ) . . . ҙຯ͸ແ͍
    ઃܭҙਤͱҟͳΔ༻్ʹ༻͍Δ͜ͱʹΑΔ໰୊
    ઃܭҙਤͱͯ͠͸ܭࢉίετ͕খ͘͞ͳΔΑ͏ʹ࡞ΒΕ͍ͯΔ
    ϥΠτίΠϯ
    scrypt (ϝϞϦΛ;ΜͩΜʹ࢖͏)
    Ethereum
    Ethash (Dagger-Hashimoto ͷਐԽܗ) (Proof of Work)
    DAG : Directed Acyclic Graph (༗޲ඇ८ճάϥϑ)
    https://github.com/ethereum/wiki/wiki/Ethash
    Keccak-256 (≈SHA-3) (μΠδΣετ) (Ethash Ͱ΋෦඼ͱͯ͠༻͍ΒΕΔ)
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.14/30

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  15. GHOST (Greedy Heaviest Observed Subtree)
    ฏۉϒϩοΫִؒΛ୹͘ઃఆ͢Δͱ
    ແବ଍Λ౿ΉϚΠφʔ͕૿͑Δ
    ແବ଍Λ౿·ͳ͍ϚΠφʔ͕ूத͠΍͍͢
    ⇒ GHOST ʹΑΓղܾΛ໨ࢦ͢
    ௚ܥͷखલͷϒϩοΫ (਌) ͚ͩͰͳ͘ɺ೿ੜͨ͠ΦʔϑΝϯͰ͋Δ “uncles”
    Λ΋ࢀর্ͨ͠Ͱɺproof of work ͷίετΛܭࢉ͠ɺ࠷΋ॏ͍ίετ͕
    ͔͔ͬͨ΋ͷΛશһ͕બ୒͢Δ (มܗͨ͠φΧϞτɾίϯηϯαε)
    ߋʹɺuncle ΋ϚΠχϯάใुΛड͚औΔ
    Ethereum Ͱ͸ uncles ͷࢀরΛ 7 ஈ֊લ·Ͱʹ੍ݶͨ͠ GHOST Λ࠾༻
    ࠷ۙͰ͸ uncle ͸ gender-neutral ͳޠͰ͋Δ ommer Ͱஔ͖׵͑ΒΕͭͭ͋Δ
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.15/30

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  16. Merkle ໦ (ϏοτίΠϯͷ৔߹)
    ͨͩ͠ Digest = SHA-256 × SHA-256 Ͱ͋ΓɺϒϩοΫϔομʹ͸ Merkle root ͕ຒΊࠐ·ΕΔ
    TX ͷଘࡏ͸ɺͦΕؚ͕·ΕΔ෦෼໦ (֤૚ͰྡʹདྷΔμΠδΣετ) ͕ఏڙ͞ΕΔͱݕূͰ͖Δ
    ΋ͱ΋ͱ͸ফඅࡁ TX ͷσʔλΛফͤΔΑ͏ʹ͢ΔͨΊʹઃܭ
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.16/30

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  17. มܗϚʔΫϧɾύτϦγΞ໦
    IUUQTFOXJLJQFEJBPSHXJLJ3BEJY@USFF
    ύτϦγΞ໦ͷྫ
    key ͸೚ҙͷόΠτྻͰ΋ OK
    PATRICIA (Practical Algorithm To Retrieve Information
    Coded In Alphanumeric) Trie (τϥΠ໦)
    (key, value) Λදݱ͠ɺݕࡧͰ͖Δ
    τϥΠ໦ͷઅΛࢀর͢ΔͨΊʹμΠδΣετ͕࢖ΘΕΔ
    ௖఺ΛϚʔΫϧϧʔτͱͯ͠ѻ͑Δ
    ૬ҧɾվ͟Μ͸ݕग़͞ΕΔ
    ֤ཁૉ͸ RLP (recursive length prefix encoding) ʹΑΓ
    ූ߸Խ͞ΕΔ
    Ethereum ʹ͓͚Δঢ়ଶɺετϨʔδ౳ͷදݱʹ࢖ΘΕΔ
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.17/30

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  18. Ethereum ͷਐԽͷํ޲
    Proof of Stake ΁ͷظ଴ͱ՝୊
    Casper
    γϟʔσΟϯά
    ͦͷଞͷٕज़ಈ޲
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.18/30

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  19. Proof of Stake ͱ͸ʁ
    ϒϩοΫΛੜ੒Ͱ͖Δ֬཰͕ɺ౰֘ίΠϯͷ࣋ͪ෼ͷଟ͞ʹԠ্ͯ͡ঢ͢Δ
    ࣍ͷར఺Λ΋ͭͱݴΘΕΔ
    ΤωϧΪʔফඅ͕௿͍ (ແࢹͰ͖Δ)
    ू໿͕ΑΓࠔ೉ (ίΠϯͷա൒਺Λॴ༗Ͱ͖Δ͔)
    ϐΞίΠϯͳͲͰ࠾༻͞ΕΔ
    Ethereum ΋Ҡߦ΁
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.19/30

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  20. Proof of Stake ͷҰൠࣜ (ݹ͍ߟ͑ํ)
    Hn
    (PD + id + t + . . .) ≤
    2n × balance
    d
    Hn
    : n Ϗοτ஋Λग़ྗ͢Δ҉߸ֶతϋογϡؔ਺
    (ex. SHA-256 (n = 256))
    PD : ௚લͷϒϩοΫͷμΠδΣετ
    id : ΞΧ΢ϯτͷࣝผࢠ (ex. ެ։ݤͷμΠδΣετ)
    t : ࣌ࠁ (ex. UNIX ࣌ࠁ (ඵ))
    balance : ౰֘ΞΧ΢ϯτͷ࢒ߴ
    d : ೉қ౓ (ex. ίΠϯͷ૯ྔ)
    μΠδΣετΛ༻͍Δ PoW ͷܗࣜͰද͞ΕΔ
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.20/30

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  21. Proof of Stake ͷ 3ͭͷ໰୊
    1. ίΠϯͷཷΊࠐΈ
    2. “Nothing at Stake”
    ୹ظత໰୊
    ௕ظత໰୊
    3. ௿ίετ 51% ߈ܸ
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.21/30

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  22. ίΠϯͷཷΊࠐΈ
    ࣋ͪ෼͕ଟ͍ํ͕༗རͳͷͰɺίΠϯ͸ཷΊࠐ·Εɺ࢖ΘΕͳ͍܏޲͕ੜ͡Δ
    ՟ฎϝσΟΞͱͯ͠ͷجຊػೳ્͕֐͞ΕΔ
    ରࡦ : Proof of Stake Velocity
    ݹ͍ίΠϯͷ࣋ͪ෼ධՁΛԼ͛Δ
    Reddcoin ͳͲͰ࠾༻͞ΕΔ
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.22/30

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  23. Nothing at Stake - ୹ظత໰୊
    ࣄނ·ͨ͸ނҙʹνΣΠϯ͕෼ذͨ͠৔߹ɺࢀՃऀʹ͸ࣄଶΛऩर͢Δಈػ͕ͳ͍
    Կ΋ౌ͚͍ͯͳ͍
    φΧϞτɾίϯηϯαε͕ҙਤ௨Γʹಇ͔ͳ͍
    φΧϞτɾίϯηϯαε = վ͟Μίετ͕࠷΋େ͖͍ྺ࢙Λ࠾༻͢Δ
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.23/30

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  24. Nothing at Stake - ௕ظత໰୊
    γεςϜΛ։࢝ͨ͠ऀ͸Կ౓Ͱ΋શମΛ΍Γ௚ͤΔ
    δΣωγεϒϩοΫͷ࣌఺Ͱ࣋ͪ෼͸ 100%
    ͦͷଞͷࢀՃऀ΋ɺ࣋ͪ෼͑͋͞Ε͹͔ͦ͜Β΍Γ௚ͤΔ
    ૉͷ Proof of Stake Ͱ͸ِ଄Λ཈ࢭͰ͖ͳ͍
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.24/30

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  25. ௿ίετ 51% ߈ܸ
    ίΠϯͷա൒਺Λऔಘ͢ΔҙࢥͱɺͦͷͨΊͷे෼ͳࢿۚͷূڌΛද໌͢Δ
    ͢ΔͱɺγεςϜͷਖ਼ৗͳҡ͕࣋ظ଴Ͱ͖ͳ͍ͱ༧૝͞ΕΔͨΊɺ
    ίΠϯͷՁ͕֨ٸམ͢Δ
    ͦ͜ͰίΠϯΛങ͍઎ΊΔ
    ݪཧతʹ͸ɺ΄ͱΜͲίετΛ෷ΘͣʹίΠϯͷա൒਺ΛೖखͰ͖Δ
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.25/30

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  26. Casper : Ethereum ͰͷऔΓ૊Έ
    Nothing at Stake ໰୊΁ͷରࡦ
    ࠾༻͞Εͳ͔ͬͨνΣʔϯͰϒϩοΫΛೝΊͨݕূऀΛേ͢Δ (Slasher)
    σϙδοτ͞Εͨ stake Λ຅ऩ͢Δ
    σϙδοτΛ෷ཱͬͯީิ͢ΔݕূऀͨͪʹΑΔ౤ථํࣜ
    100 ϒϩοΫߴຖʹʮνΣ
    οΫϙΠϯτʯΛઃ͚ɺσϙδοτֹʹԠͨ͡ॏΈ
    ෇͖ͷ౤ථͰਖ਼౰ͳνΣʔϯΛܾΊΔ
    ࣍ͷνΣ
    οΫϙΠϯτ͕ਖ਼౰Խ͞ΕΔͱɺखલͷνΣ
    οΫϙΠϯτ͸ʮ֬ఆʯ
    ͱͳΔ
    ⇒ Ͳ͜·ͰຽओతͰ͍ΒΕΔ͔ʁ
    ωοτϫʔΫͷ෼அ͕ى͖͍ͯͳ͍͜ͱ͕લఏʹࢥ͑Δ
    ى͖ͨ৔߹͸ʁ (ෳ਺ͷҟͳΔʮ֬ఆ͞Εͨʯྺ࢙͕ੜͨ͡Βʁ)
    → ϋʔυϑΥʔΫ
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.26/30

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  27. γϟʔσΟϯά (ਫฏ෼ׂ)
    ݕূ࡞ۀͷ෼ݖԽ
    εέʔϥϏϦςΟʹ޲͚ͨΞϓϩʔν
    γϟʔυ΁ͷࢀՃΛΊ͙ΔઓུతߦಈΛݗ੍͢ΔͨΊ PoS ͕લఏ
    PoW Ͱ͸γϟʔυؒͰϋογϡϨʔτͷେখ͕ੜ͡ɺ߈ܸ͕༰қ
    PoS Ͱ͸σϙδοτͨ͠ओମ͕ಛఆ͞ΕΔͷͰɺ
    γϟʔυΛΞϧΰϦζϜͰׂΓ౰ͯՄ
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.27/30

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  28. ϖΠϝϯτνϟωϧ (Bitcoin ͷ৔߹)
    A-B ؒʹ௨৴νϟωϧ͕ແ͚Ε͹ͳΒͳ͍
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.28/30

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  29. ͦͷଞͷٕज़ಈ޲
    µRaiden
    ϖΠϝϯτνϟωϧ
    Raiden Network
    ϖΠϝϯτνϟωϧؒΛϗοϓ͢Δ
    Plasma
    ϒϩοΫνΣʔϯͷ֊૚Խ
    ϒϩοΫνΣʔϯͷ՝୊ղܾʹ޲͚ͯݕ౼͞Ε͍ͯΔٕज़ͷʮશ෦ͷͤʯ
    ͋Δҙຯɺ࣮ݧγεςϜͱͯ͠ͷ໘໨༂೗
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.29/30

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  30. ࣭͝໰΍ٞ࿦Λ
    ΠʔαϦΞϜͷٕज़ — ϒϩοΫνΣʔϯج൫ٕज़ — 2019-09-18 – p.30/30

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