ΠʔαϦΞϜεέʔϦϯάͷ എܠͱ֓ཁ 2018/4/26 Osuke

Osuke @zoom_zoomzo - blog - dApp - twitter - ϑϦʔϥϯε - 2017೥ळࠒ͔ΒϒϩοΫνΣʔϯΛษڧ - ౦޻େੜ໋ཧ޻ֶ෦ଔ

1ɽεέʔϥϏϦςΟɾτϦϨϯϚ 2ɽεέʔϦϯάιϦϡʔγϣϯ ɹ2.1ɹSidechains ɹ2.2ɹState Channels ɹ2.3ɹSharding

1. Scalablity Trilemma

Scalablity Trilemma 2ͭͷཁૉΛຬͨ͢ͷ͸Մೳ͚ͩͲɺ 3ͭಉ࣌ʹຬͨ͢ͷ͕೉͍͠ʂ ௿ίετͰωοτϫʔΫʹࢀՃՄೳ े෼ʹ߈ܸίετ͕ߴ͍ ωοτϫʔΫશମͰߴ͍ॲཧೳྗ ෼ࢄੑɿ ҆શੑɿ εέʔϥϏϦςΟɿ

ݱঢ়͸ɾɾɾ εέʔϥϏϦςΟ ෼ࢄੑ ҆શੑ ෼ࢄੑͱ҆શੑΛߴਫ४ʹอͬͨ·· εέʔϥϏϦςΟΛ৳͹͍͖͍ͯͨ͠ʂ ݕূϊʔυͷܭࢉϦιʔε͕ ϘτϧωοΫʹɻ

1ɽ෼ࢄੑɿϊʔυʹඞཁͳܭࢉϦιʔεΛ௿͘อͭͨΊʹɺ ʢBlock Gas LimitΛ্͛ͯ͸μϝʣ 2ɽ҆શੑɿίϯηϯαεͷηΩϡϦςΟΛอͪɺ ʢϋογϡύϫʔΛ௿Լͤͯ͞͸μϝʣ 3ɽεέʔϥϏϦςΟɿωοτϫʔΫશମͰΑΓߴ͍ॲཧೳྗΛ࣋ͭ εέʔϥϏϦςΟ ෼ࢄੑ ҆શੑ →ϝΠϯνΣʔϯͰͷݕূ࡞ۀΛ࠷খԽ͢Δඞཁੑ →શͯͷTxΛશͯͷϊʔυ͕ݕূ͠ͳͯ͘ࡁΉΑ͏ͳํ๏

S S* Tx ঢ়ଶͱ͸ɺ - ΞΧ΢ϯτ࢒ߴ - φϯε - EVMίʔυϋογϡ - ετϨʔδϧʔτ →ϒϩοΫνΣʔϯͷঢ়ଶΛม͑Δ͜ͱʹ ܭࢉϦιʔε͕ඞཁʹͳΔ ͦ΋ͦ΋ͳͥϊʔυ͸ܭࢉϦιʔε͕ඞཁͳͷ͔ →τϥϯβΫγϣϯɾϒϩοΫΛݕূ͢Δ͜ͱʹ ܭࢉϦιʔε͕ඞཁʹͳΔ →ΠʔαϦΞϜ͸εςʔτϚγϯ

ϒϩοΫνΣʔϯͷঢ়ଶભҠΛ࠷খݶʹ͢Δ ΠʔαϦΞϜʹ͓͚ΔεέʔϦϯά͸ɺ ͱ͍͏Ξϓϩʔν

2ɽΠʔαϦΞϜͷεέʔϦϯάιϦϡʔγϣϯ ɾ1st layer → Sharding ɾ2nd layer → Sidechains, State Channels

2.1ɹSidechains

Global State ʢ҆શʣ Local State ʢ҆શ͡Όͳ͍ʣ S0 → S1 →ɾɾɾ Sn தؒঢ়ଶભҠ Flaud Proofsɿ ෆਖ਼ߦҝʹର͢Δਖ਼౰ੑͷূ໌ Sidechains (Plasma) αΠυνΣʔϯ →ϒϩοΫνΣʔϯͷঢ়ଶભҠΛ࠷খݶʹ

2.2 State Channels

Global State ʢ҆શʣ தؒঢ়ଶભҠ State Channels (Raiden Network) S0 → S1 →ɾɾɾ→ Sn-1 → Sn OPEN CLOSE →ϒϩοΫνΣʔϯͷঢ়ଶભҠΛ࠷খݶʹ

Global State ʢ҆શʣ தؒঢ়ଶભҠ State Channels (Raiden Network) ࠷৽Ͱ͸ͳ͍StateΛ ίϛοτ͠Α͏ͱ͢ΔͱϖφϧςΟʂ S0 → S1 →ɾɾɾ→ Sn-1 → Sn →ϒϩοΫνΣʔϯͷঢ়ଶભҠΛ࠷খݶʹ

2.3 Sharding

Sharding shard_id: 0 shard_id: 1 shard_id: 99 όϦσʔλʔ ɾɾɾ state: S0 state: S1 state: S99 →ݕূΛฒྻԽͯ͠ܭࢉ →ϒϩοΫνΣʔϯͷঢ়ଶભҠΛ࠷খݶʹ Global State

Sharding shard_id: 0 shard_id: 1 shard_id: 99 ɾɾɾ T = 1

Sharding shard_id: 0 shard_id: 1 shard_id: 99 ɾɾɾ T = 2

Sharding shard_id: 0 shard_id: 1 shard_id: 99 ɾɾɾ T = 3

Ethereum 2.0 • Sharding • Casper • Stateless Clients Sidechains • Plasma • Cosmos • Parity Bridge Truebit State Channels • Raiden Network • Counterfactual • FunFair …etc off-chain interactive verification εέʔϦϯάϓϩδΣΫτ

ΠʔαϦΞϜεέʔϦϯάͷϞνϕʔγϣϯ ෼ࢄੑͱ҆શੑΛ٘ਜ਼ʹ͢Δͷ͸NG ϝΠϯνΣʔϯͰͷόϦσʔγϣϯ࡞ۀʢঢ়ଶભҠʣΛ࠷খԽ ϝΠϯνΣʔϯͱͷ҆શͳStateͷಉظ͕՝୊