Plasmaの制約と緩和

by sgtn

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Plasmaͷ੍໿ͱ؇࿨

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Sg / shogochiai - Matic Network  - EXA Protocol  - Swingby Protocol  - Cryptoeconomics Lab      - ډ৔ॴ: decentralized  - ݩ ΠϯυωγΞελʔτΞοϓΫϥελ  - ݩ ौ୩ελʔτΞοϓΫϥελ - ؔ৺ɿྔࢠ෺ཧ,ਆܦՊֶ,ܕγεςϜ,෼ࢄίϯϐϡʔςΟϯά, ϦʔϯελʔτΞοϓ,ϦʔϯΞφϦςΟΫε,UXD,C2C,CTO,ࣗ ݾ૊৫Խ,͔Βͷ… Bitcoin,Ethereum,Tezos,Zilliqa,Cryptoeconomics,ethresear.ch tw: @_sgtn

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1. PlasmaΛ೉ղͨΒ͠Ί͍ͯΔ΋ͷ 2. ͦͷෳࡶ͞͸ͳͥඞཁ͔: ߈ܸऀͷࢹ఺͔Β    3. ࠷΋ޮ཰ͷΑ͍Plasmaͷֶश๏ ࠓ೔͓΅͑ͯؼͬͯ΋Β͍͍ͨ͜ͱ

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1. PlasmaΛ೉ղͨΒ͠Ί͍ͯΔ΋ͷ 2. ͦͷෳࡶ͞͸ͳͥඞཁ͔: ߈ܸऀͷࢹ఺͔Β    3. ࠷΋ޮ཰ͷΑ͍Plasmaͷֶश๏ ࠓ೔͓΅͑ͯؼͬͯ΋Β͍͍ͨ͜ͱ ະ੒ख़ͳ෼໺ͳͷͰɺ  ͋͘·Ͱͻͱͭͷ  ཧղͷ੾ΓޱͷఏҊͱͯ͠

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1. PlasmaΛ೉ղͨΒ͠Ί͍ͯΔ΋ͷ 2. ͦͷෳࡶ͞͸ͳͥඞཁ͔: ߈ܸऀͷࢹ఺͔Β    3. ࠷΋ޮ཰ͷΑ͍Plasmaͷֶश๏ ࠓ೔͓΅͑ͯؼͬͯ΋Β͍͍ͨ͜ͱ

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Mass Exitͱ͍͏Security Model Exit transactionʹର͢ΔChallenge UTXOͷඞཁੑ PlasmaCashͷDeposit Coin Child chainͷதͷConsensus Plasma͸Ethereumͳͷ͔ʁ Sidechainಉ࢜ͷCommunication Deposit,Exit,Commit txͷblock withholding

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Mass Exitͱ͍͏Security Model Exit transactionʹର͢ΔChallenge UTXOͷඞཁੑ PlasmaCashͷDeposit Coin Child chainͷதͷConsensus Plasma͸Ethereumͳͷ͔ʁ Sidechainಉ࢜ͷCommunication ઐ໳༻ޠ͕ଟ͍Ͱ͢Ͷ Deposit,Exit,Commit txͷblock withholding

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Mass Exitͱ͍͏Security Model Exit transactionʹର͢ΔChallenge UTXOͷඞཁੑ PlasmaCashͷDeposit Coin Child chainͷதͷConsensus Plasma͸Ethereumͳͷ͔ʁ Sidechainಉ࢜ͷCommunication Unspent  Trans(=TX)action  Output Ͱ͢ Deposit,Exit,Commit txͷblock withholding

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Mass Exitͱ͍͏Security Model Exit transactionʹର͢ΔChallenge UTXOͷඞཁੑ Child chainͷதͷConsensus Plasma͸Ethereumͳͷ͔ʁ Sidechainಉ࢜ͷCommunication Deposit,Exit,Commit txͷblock withholding PlasmaCashͷDeposit Coin blockͷbroadcastͷ  ނҙ͋Δ͍͸աࣦʹΑΔ  ະఏग़ঢ়ଶ

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Mass Exitͱ͍͏Security Model Exit transactionʹର͢ΔChallenge UTXOͷඞཁੑ Child chainͷதͷConsensus Plasma͸Ethereumͳͷ͔ʁ Sidechainಉ࢜ͷCommunication PlasmaCashͷDeposit Coin ෆಛఆଟ਺ͰߦΘΕΔ  ෆਖ਼withdrawal߈ܸ΁ͷ  ରࡦͰ͢(witnessing) Deposit,Exit,Commit txͷblock withholding

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Mass Exitͱ͍͏Security Model Exit transactionʹର͢ΔChallenge UTXOͷඞཁੑ Child chainͷதͷConsensus Plasma͸Ethereumͳͷ͔ʁ Sidechainಉ࢜ͷCommunication PlasmaCashͷDeposit Coin Deposit,Exit,Commit txͷblock withholding ߦಈܦࡁֶ/਺ཧϞσϧͷࠞͬͨ͟  γεςϜ͔Βͷenforcement(ཁ੥)Ͱ  ܥͷηΩϡΞ͞Λอূ͢Δํ޲ੑ

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Mass Exitͱ͍͏Security Model Exit transactionʹର͢ΔChallenge UTXOͷඞཁੑ Child chainͷதͷConsensus Plasma͸Ethereumͳͷ͔ʁ Sidechainಉ࢜ͷCommunication PlasmaCashͷDeposit Coin Deposit,Exit,Commit txͷblock withholding ࢠνΣʔϯ΋ϒϩοΫνΣʔϯͱ  ίϯηϯαεΛ࣋ͪ͏ΔͷͰ  ͦͷηΩϡϦςΟΛߟ͑Δ

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Mass Exitͱ͍͏Security Model Exit transactionʹର͢ΔChallenge UTXOͷඞཁੑ Child chainͷதͷConsensus Plasma͸Ethereumͳͷ͔ʁ Sidechainಉ࢜ͷCommunication PlasmaCashͷDeposit Coin Deposit,Exit,Commit txͷblock withholding Mass Exitͷ  Rootchainෛՙʹର͢Δ  mitigation(؇࿨)

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Mass Exitͱ͍͏Security Model Exit transactionʹର͢ΔChallenge UTXOͷඞཁੑ Child chainͷதͷConsensus Plasma͸Ethereumͳͷ͔ʁ Sidechainಉ࢜ͷCommunication PlasmaCashͷDeposit Coin Deposit,Exit,Commit txͷblock withholding Plasma͸Solidityѥछ΍  tendermintΛ࢖͑Δɻ  ਌νΣʔϯ͸ETH͡Όͳ͘΋Մ

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1. PlasmaΛ೉ղͨΒ͠Ί͍ͯΔ΋ͷ 2. ͦͷෳࡶ͞͸ͳͥඞཁ͔: ߈ܸऀͷࢹ఺͔Β    3. ࠷΋ޮ཰ͷΑ͍Plasmaͷֶश๏ ࠓ೔͓΅͑ͯؼͬͯ΋Β͍͍ͨ͜ͱ

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1. Block withholding߈ܸ  2. ෆਖ਼ͳwithdrawal

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1. Block withholding߈ܸ  2. ෆਖ਼ͳwithdrawal

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1. Block withholding߈ܸ    - PoS͸୭Ͱ΋ࢀՃͰ͖ͯ͠·͏  - 1epoch 1ਓ͚ͩϒϩοΫ࡞ΕΔ  - blocktimeҎ্hold͞ΕͨΒskipͱ͍͏҆௚ͳઃܭ͸ɺނҙͷskip ͳͷ͔ނোͳͷ͔஗Ԇͳͷ͔൑அͰ͖ͣ೉͍͠ʢ͓ͦΒ͘Ϗβϯν ϯނোϞσϧʁʣ  - ͕ͨͬͯ͠ނҙʹࢭΊͨΓͰ͖Δ  - ͦͷޙPlasma͸mass exitΛཁ੥͢Δ  - Ұఆ࣌ؒͰexit͠ͳ͍ਓ͸ࢿۚ຅ऩ  - (ίϛϡχςΟͰٞ࿦ෆे෼ʹݟ͑Δ͕) exitޙʹ࠶։࡞ۀΛ͢Δ  - ํ਑ʹΑΔ͕evilͳwithholderͷcollateral(ڙୗ/୲อ)͸຅ऩ͢Δ  - StakerΛKYCͯ͠ban͢ΔΞΠσΞͱ͔΋ͨ·ʹݟΔ͕censorship- resistance͕ͳ͘ͳΓ࣋ଓੑ͕ͳ͘ͳΔ

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1. Block withholding߈ܸ    - PoS͸୭Ͱ΋ࢀՃͰ͖ͯ͠·͏  - 1epoch 1ਓ͚ͩϒϩοΫ࡞ΕΔ  - blocktimeҎ্hold͞ΕͨΒskipͱ͍͏҆௚ͳઃܭ͸ɺނҙͷskip ͳͷ͔ނোͳͷ͔஗Ԇͳͷ͔൑அͰ͖ͣ೉͍͠ʢ͓ͦΒ͘Ϗβϯν ϯނোϞσϧʁʣ  - ͕ͨͬͯ͠ނҙʹࢭΊͨΓͰ͖Δ  - ͦͷޙPlasma͸mass exitΛཁ੥͢Δ  - Ұఆ࣌ؒͰexit͠ͳ͍ਓ͸ࢿۚ຅ऩ  - (ίϛϡχςΟͰٞ࿦ෆे෼ʹݟ͑Δ͕) exitޙʹ࠶։࡞ۀΛ͢Δ  - ํ਑ʹΑΔ͕evilͳwithholderͷcollateral(ڙୗ/୲อ)͸຅ऩ͢Δ  - StakerΛKYC͓͍ͯͯ͠࠶։࣌ʹର৅Λban͢ΔΞΠσΞͱ͔΋ͨ ·ʹݟΔ͕censorship-resistance͕ͳ͘ͳΓ࣋ଓੑ͕ͳ͘ͳΔ ͪΐͬͱͨ͠ϓϩτίϧ΁ͷมߋ͕  censorship-resistance(ݕӾ଱ੑ)Λ  ഁյ͢Δ͜ͱͷ޷ྫ

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1. Block withholding߈ܸ  2. ෆਖ਼ͳwithdrawal

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2. ෆਖ਼ͳwithdrawal  - sidechainͷ2way-pegΛtrustlessʹ࡞Δཁ͕݅͋Δ    - depositͷϑϩʔ  - rootchainͷcontract addressʹlock  - ͦͷॲཧͷreceiptΛchild chianଆͷweb3౳͔Β؂ࢹ  - ͦͷϦεφʔͰchild chainଆʹUTXOΛ࡞੒   - withdrawalͰͷ߈ܸϑϩʔͱ؇࿨  - ڙୗͱڞʹɺਖ਼ن͔ڏِ͔ෆ໌ͳҾ͖ग़͠τϥϯβΫγϣϯ͕Plasma chain͔Β rootchainͷίϯτϥΫτʹఏग़͞ΕΔʢҾ਺͸UTXO_IDʣ  - UTXO_ID͕࠷৽͔ͭਖ਼౰ͷ΋ͷͰ͋Ε͹challengeظؒத୭΋ҙٛΛਃཱͯ͠Δ͜ͱ ͕Ͱ͖ͳ͍͸ͣͳͷͰɺͦͷ··Ҿ͖ग़͞ΕΔ  - ͦͷUTXO_IDΑΓ΋৽͍͠UTXO͕ݟ͔ͭͬͨ৔߹ɺdisputer(withdrawalΛ؂ࢹ͢Δ ਓ)͸ɺͦͷIDͱڞʹexitChallengeͱ͍͏ҟٞਃཱͯ͠ίϯτϥΫτΛ࣮ߦ͢Δ  - ਌νΣʔϯʹτϥϯβΫγϣϯ͕ͨ͘͞Μ࡞ΒΕΔ  - ΞΧ΢ϯτϞσϧͰ΍Δͱҟٞਃཱͯ͠ܭࢉίετ͕ΑΓߴ͍ʢͨͿΜPlasma chain ͷreceiptΛूܭ͢Δײ͡ʁʣ

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1. PlasmaΛ೉ղͨΒ͠Ί͍ͯΔ΋ͷ 2. ͦͷෳࡶ͞͸ͳͥඞཁ͔: ߈ܸऀͷࢹ఺͔Β    3. ࠷΋ޮ཰ͷΑ͍Plasmaͷֶश๏ ࠓ೔͓΅͑ͯؼͬͯ΋Β͍͍ͨ͜ͱ

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ٞ࿦ gi ron

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ׂͱϑϩʔܕͰϥΠτͳٞ࿦  twitter  reddit  telegram  slack  ετοΫܕͰϔϏʔͳٞ࿦  ethresear.ch  EIP(github issue) 