IPv6-mostly field report from RubyKaigi 2026

https://github.com/ruby-no-kai/rubykaigi-net https://github.com/sorah/xlat

Transcript

1. IPv6-mostly Field Report from RubyKaigi Sorah Fukumori https://sorah.jp/ @ Internet Week 2025
2. ✦ Sorah Fukumori (そらは) https://sorah.jp/ ✦ RubyKaigi Organizer (2018-) ✦ RubyKaigi NOC Lead (2017-) ✦ AS59128 ژେϚΠίϯΫϥϒ (2017-) ✦ ຊۀ: Principal Engineer for IVRy (2025/4-) ✦ झຯ: ετϦʔϚʔ/VTuber͓ͨ͘, ΦϯήΩ, FFXIV Self Intro
3. ✦ 本スライドは以下で公開してます (写真撮る必要ないです) ✦ 本プログラム内でもう話されていて重複する内容は スキップしていきます ✦ 結構な速度で話すので、→ おすすめです Slide https://speakerdeck.com/sorah/ iw2025-rubykaigi-v6mostly
4. ✦ RubyKaigi ͸ɺϓϩάϥϛϯά ⾔ ޠ Ruby ʹؔ͢Δੈք࠷ ⼤ ڃͷࠃࡍΧϯ ϑΝϨϯεͰ͢ɻ ࠷ઌ୺ͷٕज़ηογϣϯͷ਺ʑ͕൸࿐͞ΕΔϓϩάϥϚʔ ζΧϯϑΝϨϯεͱͯ͠ɺ·ͨ Ruby ͷॲཧܥ ⾃ ମͷ։ൃऀΛूΊͯٞ࿦Λ ଅਐ͢ΔΤϯδϯͱͯ͠ɺ͞Βʹɺӳޠɾ ⽇ ຊޠΛެ ⽤ ޠͱͨ͠ੈքతͳ Ruby ίϛϡχςΟͷަྲྀͷϋϒͱͯ͠΋ɺ ⼤ ͖ͳ໾ׂΛ୲͍ͬͯ·͢ɻ ✦ ೔ຊ֤஍Λసʑͱ೥1։࠵͢Δࠃࡍձٞ ✦ 1,200-1,500 ਓن໛, Assocs ͸ਓ਺ * 1.1 ͘Β͍, 200-400Mbps ✦ https://rubykaigi.org/2025/ About RubyKaigi
5. ✦ RubyKaigi NOC Ͱ͸ Kaigi on Rails ͷ Wi-Fi ఏڙ΋࣮ࢪ ✦ ಉ͡๏ਓ֨Λڞ༗͢Δ͕ओ࠵ɾӡӦํ਑͸ҟͳΔɺ ೥1ɺ౦ژͰ։࠵͞ΕΔࠃ಺ͷٕज़ΧϯϑΝϨϯε ✦ Kaigi on Rails ͸ ʮॳֶऀ͔Β্ڃऀ·Ͱָ͕͠ΊΔWebܥͷٕज़ΧϯϑΝϨϯεʯ Λίϯηϓτʹɺٕज़ΧϯϑΝϨϯεࢀՃͷෑډΛ௿͘͢Δ͜ͱΛҙਤͯ͠اը͞Ε ͍ͯ·͢ɻҰํɺͦΕͱಉ࣌ʹϕςϥϯͷٕज़ऀ΋ຬ଍ͤ͞ΔΑ͏ͳߴ౓ͳൃද΋ఏ ڙ͍ͯ͘͜͠ͱͰɺ্هͷίϯηϓτΛݱ࣮Խ͍͖͍ͤͯͨ͞ͱߟ͍͑ͯ·͢ɻ ✦ https://kaigionrails.org/ About Kaigi on Rails
6. ✦ গ਺ਫ਼Ӷɺলྗɻݻఆϝϯόʔ + ืूͰຖ೥ͪΐͬͱͣͭೖΕସΘΓ ✦ ͦͷதͷ͞Βʹগ਺͕ L3ʙL4 Ҏ্Λ৮͍ͬͯΔ ✦ ࠷ۙ͸࠷৽ͷ RFC Λ࣮૷ͨ͠Γ (DNS over TLS/HTTPS/QUIC etc) ✦ Transit/PA Λ AS59128 KMC ͔Β౉͍ͯ͠ΔͷͰ KMC ϝϯόʔଟΊ RubyKaigi NOC
7. ✦ ੒Ռ෺͸͍͍ͩͨશͯެ։ ✦ https://github.com/ruby-no-kai/rubykaigi-net (rknet) ✦ Issue ΍ Grafana Dashboard ΋ύϒϦοΫ ✦ ࠓճͷ࿩ʹؔ࿈͢Δॾʑ΋͋Δ͸ͣ ✦ ͦͷଞϒϩά౳ͷ write-up ΋ README ͔ΒϦϯΫ͞Ε͍ͯ· ͢ Openness
8. ✦ IPv 6 -mostly とは何か ✦ IPv 6 Transition Technologies Recap ✦ IPv 6 -mostly のモチベーション ✦ Actual deployment and issues at RubyKaigi Agenda ຊϓϩάϥϜதͷଞͷηογϣϯͱॏͳΔ෦෼΋͋Γ·͕͢ɺ اۀ಺ωοτϫʔΫ΍ΠϕϯτωοτϫʔΫ؅ཧऀͷίϯςΩετͰ͓఻͑͠·͢
9. IPv6-mostly ͱ͸Կ͔?
10. ✦ IPv6-mostly ͱ͸? ✦ Native IPv4 ͸ඞཁͳ୺຤ʹ͚ͩఏڙ͢ΔωοτϫʔΫ ✦ IPv6-mostly ରԠͷ୺຤͸ IPv4 Λ NAT64 ӽ͠ʹ࢖͏ ✦ ಛ௃: ✦ ಉ͡ L2 υϝΠϯͰڞଘɾίϯτϩʔϧͭͭ͠ҠߦͰ͖Δ ✦ ෆཁͳ୺຤ͷ DHCPv4 ͷΞυϨεׂ౰ΛলུͰ͖Δ ✦ IPv4઀ଓ͸୺຤͕௚઀IPv6Ҡߦٕज़Λ࢖͍αϙʔτ IPv6-mostly Ͱ޿͕Δ IPv4 ӡ༻ͷબ୒ࢶ ੲ͔Β͋Δ෺ΛؚΊෳ਺ͷ RFC Λར༻࣮ͯ͠ݱ͍ͯ͠·͢ɻ draft-ietf-v6ops-6mops-04 ͕ “IPv6-mostly” ͷنఆʹͳΔ༧ఆ
11. ✦ ۩ମతʹ͸୺຤͕ IPv4 Lease ΛΦϓτΞ΢τՄೳͰɺ͔ͭ NAT64 ͕͋ΓɺͦΕʹඞཁͳ৘ใΛऔಘͰ͖Ε͹ྑ͍ ✦ DHCPv4 Option 108 ͱPref64::/n ͷσΟεΧόϦʔ΍௨஌ ✦ RFC 8925 (Option 108) — IPv4 Lease ͳͯ͘΋͍͍Αͷҙࢥදࣔ ✦ RFC 8781 (RA PREF64) — IPv6 RA Ͱ NAT64 pre fi x Λ௨஌ ✦ RFC 7050 (DNS-based Discovery) — RFC 9872 Ͱඇਪ঑*ʹ IPv6-mostly Ͱ޿͕Δ IPv4 ӡ༻ͷબ୒ࢶ * normative ͳ NOT RECOMMENDED Ͱ͸ͳ͘ɺRFC 8781 ͕࢖͑ΔͳΒͦͷํ͕ྑ͍ͱ໰୊఺෇͖Ͱٞ࿦͞Ε͍ͯ·͢
12. ✦ NAT64 Λར༻͢Δ͕ DNS64 Ͱ͸ͳ͍఺ʹ஫ҙ ✦ DNS64 ͸໰୊఺͕ଟ͍ ✦ ఏڙ͞Ε͍ͯΔNAT64ʹ߹ΘͤͨDNSϦκϧόΛར༻͢Δඞཁ (Public DNSͱ͔֤छVPNͰഁ୼) ✦ DNSSEC ඇޓ׵ ✦ IPv4Λલఏͱͨ͠APIʹґଘͨ͠ιϑτ΢ΣΞͱͷޓ׵ੑ (AF_INETͱ͔IPΞυϨε௚઀ଓͱ͔) NAT64?
13. IPv6 Transition Technologies ͓͞Β͍
14. ✦࿩ΛਐΊΔલʹ IPv6 Ҡߦٕज़ (IPv4aaS) ͷ͓͞Β͍ ✦ ※ 6rd ͷΑ͏ʹ IPv4 ωοτϫʔΫͰ IPv6 Λఏڙ͢Δٕज़Ͱ͸ͳ͘ɺ DS-Lite ΍ MAP-E ͱ͍ͬͨ IPv6 ωοτϫʔΫͰ IPv4 ઀ଓੑΛ ఏڙ͢Δखஈͷํ ✦ ຊϓϩάϥϜ1ͭ໨ͷηογϣϯͰ͍͍ͩͨ৮ΕΒΕ͍ͯΔͷͰαοͱ IPv6 Transition Technologies (IPv4aaS) ͷ͓͞Β͍
15. ✦·ͣύέοτͷऔΓѻ͍Ͱ 2 ํࣜ ✦4in6 encapsulation ※ॴҦτϯωϧ IPv4ύέοτΛIPv6ύέοτͱͯ͠ΧϓηϧԽ ✦4-6-4 translation IPv4ϔομΛIPv6ϔομʹม׵ͯ͠IPv4ϔομʹ໭͢ IPv6 Transition Technologies (IPv4aaS) ͷ෼ྨͷ࣠ 1 ͋ΘͤͯಡΈ͍ͨ: RFC 9313 Pros and Cons of IPv6 Transition Technologies for IPv4-as-a-Service (IPv4aaS)
16. ✦ͭ͗ʹ IPv4 NAT ͷѻ͍Ͱ 2 ํࣜ ✦(Carrier Grade) NAT IPv4aaSଆઃඋͰ IPv4 NAPT Λߦ͏ ✦A+P (Address plus Port) IPv4aaS͔ΒCustomer Edgeଆʹ༧ΊIPv4ΞυϨεͱ ϙʔτൣғΛׂ౰, CEଆͰNAPT͓͍ͯͯ͠΋Β͏ IPv6 Transition Technologies (IPv4aaS) ͷ෼ྨͷ࣠ 2 *ඞͣ͠΋ Carrier Grade Ͱ͋Δඞཁ͸͋Γ·ͤΜ
17. ✦࣮ࡍͷҠߦٕज़ʹ͋ͯ͸ΊΔͱɺ͜͏: IPv6 Transition Technologies (IPv4aaS) ͷ͓͞Β͍: ·ͱΊ CGNAT A+P 4in6 DS-Lite MAP-E 4-6-4 464XLAT DNS64 MAP-T * DNS64͸4-6-4ͱ͍͏͔6-4͚ͩͲศٓతʹ4-6-4ͷͱ͜Ζʹॻ͍ͯ·͢
18. ✦4-6-4 translation Ͱ͸ͲͪΒ΋ NAT64 Λར༻ IPv6 Transition Technologies (IPv4aaS) ͷ͓͞Β͍: ·ͱΊ CGNAT A+P 4in6 DS-Lite MAP-E 4-6-4 464XLAT DNS64 MAP-T * MAP-T ͸ CE Ͱ NAPT44 Λ͢ΔͨΊ PE ͸ Stateless NAT64
19. ✦ DS-Lite ͸୯ͳΔτϯωϧͰ͸ͳ͘ IPv6 ϔομͷ IPv6 source address ΋ؚΊͨ NAPT ςʔϒϧΛ࣋ͭඞཁ͕͋Δ ✦ ୯ʹdecapͯ͠NAPTॲཧΛ͢Ε͹͍͍Θ͚Ͱ͸ͳ͘ɺ NAPTͱdecapΛಉ࣌ʹͰ͖Δઃඋ͕ඞཁ ✦ A+Pํࣜ΋MAP-EͳͲͦΕͧΕʹରԠͨ͠ઃඋ͕ඞཁ ͜Ε·Ͱͷٕज़͸ΘΓͱ ISP/Carrier ޲͚
20. ✦ NAT64, 4-6-4 translation ͸ͦͷ෼ͭ͡͸खܰͰ͋Δ ✦ ΋ͪΖΜେن໛ʹͳΔͱ NAPT ઃඋͷεέʔϧ໰୊͸ൃੜ͢Δ ✦ DNS64 ͸ݫ͔͕ͬͨ͠ɺͦΕҎ֎Ͱ׆͔͢ํ๏͕গͳ͔ͬͨ ✦ ωοτϫʔΫઃඋͱͯ͠͸ɺԼه͕͋Ε͹ྑ͍ ✦ Customer ଆ: NAT64 pre fi x (Pref64::/n) ΁ͷܦ࿏ ✦ NAT64 ઃඋ: Customer ΁ͷ IPv6 ܦ࿏ͱ IPv4 ઀ଓੑ ✦ ্هͷؒͷ Backbone ͸७ਮͳ IPv6 ωοτϫʔΫ NAT64 ͸खܰ
21. ✦ NAT64, 4-6-4 translation ͸ͦͷ෼ͭ͡͸खܰͰ͋Δ ✦ ΋ͪΖΜେن໛ʹͳΔͱ NAPT ઃඋͷεέʔϧ໰୊͸ൃੜ͢Δ ✦ DNS64 ͸ݫ͔͕ͬͨ͠ɺͦΕҎ֎Ͱ׆͔͢ํ๏͕গͳ͔ͬͨ ✦ ωοτϫʔΫઃඋͱͯ͠͸ɺԼه͕͋Ε͹ྑ͍ ✦ Customer ଆ: NAT64 pre fi x (Pref64::/n) ΁ͷܦ࿏ ✦ NAT64 ઃඋ: Customer ΁ͷ IPv6 ܦ࿏ͱ IPv4 ઀ଓੑ ✦ ্هͷؒͷ Backbone ͸७ਮͳ IPv6 ωοτϫʔΫ NAT64 ͸खܰ
22. ✦ RFC 6877 (464XLAT) ✦ ୺຤Ͱ “CLAT” ͱͯ͠ IPv4 <> IPv6 ϔομͷ translation (RFC 7915 aka SIIT) Λͯ͠ఏڙ͞Ε͍ͯΔ NAT64 pre fi x Λར༻͢Δํ๏ ✦ ୺຤ͷதͰ local 192.0.0.2, fi rst hop 192.0.0.1 (ྫ) ͷΑ͏ͳ ωοτϫʔΫ͕ઃఆ͞ΕΔͨΊɺIPv4 ͷ API ͱ΋ޓ׵ੑ͕͋Δ ✦ “PLAT” Ͱ͋ΔωοτϫʔΫʹ͋Δ Stateful NAT64 ػೳ͸ RFC 6146 ͦͷ·· ✦ 2013-2014 ࠒ͔Β US T-Mobile Ͱӡ༻͞Ε͍ͯΔރΕͨख๏ 464XLAT for the rescue
23. ✦ 464XLAT ͸ 2013-2014 ࠒ͔Β US T-Mobile Ͱӡ༻͞Ε͍ͯΔ, ރΕͨख๏ (ͱ͍͏͔ T-Mobile ࣾһൃҊ(ͷ͸ͣ) ✦ Android 4.3ʙ, iOS 12 ࠒʙ ✦ ୺຤ͷ CLAT ͸ࣄલʹઃఆ͞Εͨ mobile network ΍ IPv6 only Ͱ NAT64(DNS64) ͕͋Δ Wi-Fi/Wired network ʹ ݶͬͯͷىಈͩͬͨ ✦ Wi-Fi ౳Ͱ΋༗ޮʹͳΔΑ͏ʹͳͬͨͷ͸ iOS 17 ࠒ, Android 5.1 ͷΑ͏ 464XLAT for the rescue
24. ✦ IPv4aaS ͷ͏ͪ DS-Lite, MAP-E ͸ ISP ޲͚ͩ͠ɺCPE ΋ ωοτϫʔΫػث΁ͷ࣮૷͕த৺ ✦ NAT64 ͸ઃඋଆ͕εςʔτϑϧ͕࣮ͩ͸͓खܰ ✦ DNS64 ͸ݫ͔͕ͬͨ͠ 464XLAT ͕ battle-tested ✦ Apple ୺຤΍ Android Ͱ͸ 464XLAT ͷ୺຤ଆػೳ CLAT ͕ NAT64 ͕͋Δ IPv6-only network Ͱ͸༗ޮʹͳ͍ͬͯΔ Recap
25. Re: IPv6-mostly ͱ͸Կ͔?
26. ✦ IPv4v6 dualstack, IPv6 (native) + IPv4 (NAT64), IPv4 only Λ୺຤ʹΑͬͯ࢖͍෼͚Ͱ͖ΔωοτϫʔΫͷ͜ͱ ✦ DHCPv4 Option 108 (IPv6-only preferred) ͕伴 ✦ αʔόʔ͸͜ΕΛड৴ͨ͠Β IPv4 lease Λলུͯ͠ྑ͍ (Option 108 ΛૹΓฦ͢ඞཁ͸͋Δ) ✦ ୺຤͸ 108 ͕ૹΓฦ͞Ε͖ͯͨΒ Native IPv4 ΛΦϑʹͯ͠ɺ NAT64 ͕͋Ε͹ CLAT Λىಈ͢Δ Re: IPv6-mostly ͱ͸Կ͔? * ࢓্༷͸ IPv4 ׬શʹෆཁ͔΋͠Εͳ͍͠ɺݱ࣮తʹ͸ NAT64 (464XLAT) ͚ͩͲ DNS64 ͔΋͠Εͳ͍ͦ͠ΕҎ֎ͷ Ҡߦํ๏͔΋͠Εͳ͍ɻ͜͜͸ DHCPv4 Φϓγϣϯͷ RFC ͱͯ͠͸ఆΊ͍ͯͳ͍
27. ✦ IPv4v6 dualstack, IPv6 (native) + IPv4 (NAT64), IPv4 only Λ୺຤ʹΑͬͯ࢖͍෼͚Ͱ͖ΔωοτϫʔΫͷ͜ͱ ✦ DHCPv4 Option 108 (IPv6-only preferred) ͕伴 ✦ αʔόʔ͸͜ΕΛड৴ͨ͠Β IPv4 lease Λলུͯ͠ྑ͍ (Option 108 ΛૹΓฦ͢ඞཁ͸͋Δ) ✦ ୺຤͸ 108 ͕ૹΓฦ͞Ε͖ͯͨΒ Native IPv4 ΛΦϑʹͯ͠ɺ NAT64 ͕͋Ε͹ CLAT Λىಈ͢Δ Re: IPv6-mostly ͱ͸Կ͔? * ࢓্༷͸ IPv4 ׬શʹෆཁ͔΋͠Εͳ͍͠ɺݱ࣮తʹ͸ NAT64 (464XLAT) ͚ͩͲ DNS64 ͔΋͠Εͳ͍ͦ͠ΕҎ֎ͷ Ҡߦํ๏͔΋͠Εͳ͍ɻ͜͜͸ DHCPv4 Φϓγϣϯͷ RFC ͱͯ͠͸ఆΊ͍ͯͳ͍
28. ✦ DHCPv4 ઃඋ͸ड৴ͨ͠ Option 108 ʹରͯ͠ॲཧΛܾΊΒΕΔɻ ྫ͑͹: ✦ Ұఆͷׂ߹Ͱ Option 108 Λฦ͢ ✦ ୺຤ʹΑͬͯ Option 108 Λฦ͢ ✦ Option 108 ΛҰ෦ͷ୺຤Ͱ͸ฦ͞ͳ͍ ✦ ͭ·Γɺαʔόʔଆ͔Βॊೈʹ IPv6 + IPv4aaS ΁ͷҠߦΛ ૢ࡞Ͱ͖Δ DHCPv4 Option 108 (IPv6-only preferred) ͕伴
29. ✦ ϢʔβʔʹωοτϫʔΫΛબ୒ͤͨ͞Γɺؤுͬͯ Dynamic VLAN ౳Ͱ IPv6-only network ΁༠ಋ͢Δͷ͸ݱ࣮తͰ͸ͳ͍ ✦ Ϣʔβʔ͸Θ͟Θ͟બ୒͠ͳ͍͠ɺμϝͳΒ໧ͬͯ໭ͬͯ͠·͏ ✦ Dualstack ͳಉҰͷ L2 υϝΠϯ 1 ͭͰ DHCPv4 ΦϓγϣϯͰ IPv4 usage Λ੍ޚͰ͖Δͷ͸ڧΈ ✦ ஈ֊తʹ IPv4 ϓʔϧ΍ NAPT44 ઃඋΛεέʔϧμ΢ϯͰ͖Δ ✦ Ϣʔβʔʹ઀ଓઌΛҙࣝͤͨ͞Γ͠ͳͯ͘ྑ͍ ஈ֊తҠߦͷϝϦοτ
30. ✦ RFC 8781 (RA PREF64) ʹΑͬͯ ICMPv6 Router Advertisement ʹ Pref64::/n ৘ใΛؚΊΔ͜ͱ͕Մೳʹͳͬͨ ✦ ͜Ε·Ͱͷ RFC 7050 (DNS-based discovery) ͸ηΩϡϦςΟ΍ ੑೳ໘ɺωοτϫʔΫʹରԠͨ͠Ϧκϧόʹґଘ͢Δͱ͍ͬͨ໰୊ ͕͋ͬͨ (RFC 9872 Ͱٞ࿦) ✦ RFC 8781 ʹΑͬͯ RFC 7050 ͸ෆཁʹ RA PREF64 ΋ޙԡ͠ ͳ͓ɺRFC 7050 ͸ DNS64 Λϑϧ࣮૷͢Δඞཁ͸ͳ͘ ipv4only.arpa ͷ AAAA Ϩίʔυ͚࣮ͩ૷͢Ε͹ྑ͍
31. ✦ IPv6-mostly ͸طଘͷ dualstack ͳ L2 υϝΠϯͰ୺຤Λ IPv6 native + NAT64 ʹدͤΔͨΊͷ࢓૊Έ ✦ ૅͷ 464XLAT ͸ϞόΠϧωοτϫʔΫͰେن໛ͳӡ༻࣮੷ ✦ DHCPv4 ΦϓγϣϯΛར༻ͨ͠ॊೈͳ੍ޚ ✦ Windows Ҏ֎ͷαϙʔτ͸ॱௐ ✦ Windows 11 ΋ Private Preview ͷࠂ஌͕ग़ͨͱ͜Ζ Recap
32. IPv6-mostly ͷϞνϕʔγϣϯ
33. ✦ ۀք಺Ͱ΋ϓϨΠϠʔͷཱ৔ʹΑͬͯϞνϕʔγϣϯ͕ҟͳΔ (ISP, ωοτϫʔΫػثϕϯμʔ, OSϕϯμʔ, اۀ಺ͷ؅ཧऀ, etc) ✦ ࣾ಺ωοτϫʔΫ΍ΠϕϯτωοτϫʔΫͷ؅ཧऀͱͯ͠ͷࢲݟ IPv6-mostly ͸୭͕خ͍͠?
34. ✦ (ಛʹࠃ಺Ͱ͸) MAP-E ΍ DS-Lite ͕े෼ރΕͨࠓɺબ୒ࢶͱͯ͠ ௥Ճ͢Δڧ͍Ϟνϕʔγϣϯ͸ͳ͍͔΋? ૝૾……ɻ ✦ CPE͕Option 108ͱRA PREF64ʹରԠ͢ΔϞνϕʔγϣϯ͸? ✦ ফඅऀ޲͚ʹఏڙ͢Δʹ͸ٕज़αϙʔτίετ͕૿͚͔ͩ͢΋? LAN ಺ͷ IPv4 ௨৴΋੍໿͕͔͔Δ ✦ ※ϞόΠϧωοτϫʔΫͰ͸طʹେن໛ͳ࣮੷͕͋Δ ✦ ISPࢹ఺ͩͱDS-Liteಉ༷εςʔτϑϧNAPTͷӡ༻ίετ΋͔͔Δ Home ISP ΍ Consumer ࢹ఺
35. ✦ Ϟνϕʔγϣϯͱ͍͏͔ 464XLAT ͷར఺ ✦ NAT64+DNS64 ͱҧ͍ CLAT ͩͱ IPv4 ґଘͷ API ͕࢖͑ޓ׵ੑ ͕ߴ͘ɺΞϓϦέʔγϣϯ։ൃऀ͸ҙࣝ͢Δඞཁ͕ͳ͍ͷ͕େ͖͍ ✦ Apple App Store ͸ NAT64 ར༻ͯ͠΋ྑ͍ͷͰ IPv6-only ؀ڥ Ͱͷಈ࡞Λ৹ࠪཁ݅ʹؚΊ͍ͯΔ͕ɺCLAT લఏͩͱෛ୲͕͍ͩ ͿݮΔ͸ͣ ✦ Wi-Fi ΍ Wired ͷ LAN Ͱ΋ 464XLAT ʹग़དྷΔͷ͸ྑ͍͜ͱ ΞϓϦέʔγϣϯ։ൃऀࢹ఺
36. ✦ IPv4 singlestack → IPv4/IPv6 dualstack ʹͳͬͨͱͯ͠΋, IPv4 ΁ͷґଘ͕ͳ͔ͳ͔ແ͘ͳΒͳ͍ ✦ IPv6 singlestack ΁ͪΐͬͱ͍ͣͭ࣋ͬͯͨ͘Ίͷ࢓૊Έ͕ ඞཁ Internet Engineering ࢹ఺
37. ✦ ͜͜·Ͱղઆ͖ͯͨ͠Α͏ʹɺNAT64 ͷΞΫηεωοτϫʔΫͰͷ ॊೈͳ༗ޮԽͱ͍͏఺Ͱɺͪ͜Β͕ओͳ༻్͔ͳ? ͱࢥ͍ͬͯΔ ✦ CPE Ͱ͸ͳ͘୺຤͔Β௚઀ͭͳ͕Δಛ௃͕׆͖Δ ✦ ࣗࣾ಺Ͱ؅ཧ͢Δ IPv4 ϓʔϧ΍ઃඋͷن໛ΛͪΐͬͱͣͭॖখͰ͖ Δͷ͸ڧΈ ✦ ܦ࿏දΛ૿΍ͣ͞ʹ Pref64::/n ͷ࢖͍෼͚Ͱ IPv4 ग़ޱΛ࢖͍෼ ͚Δͷ΋Մೳ ✦ ωοτϫʔΫ಺ͷ1ͭͷΦʔόʔϨΠػೳͱͯ͠IPv4Λଊ͑ΒΕΔ Enterprise ࢹ఺
38. ✦ RubyKaigi ʹݶΒͣ, ֤छNOG΍RIRɺ·ͨIETF౳ඪ४Խஂମͷ ΠϕϯτͰ࠾༻͕ਐΜͰ͍Δ ✦ ͜Ε͸ͲͪΒ͔ͱݴ͑͹ςϯϙϥϦͳωοτϫʔΫ͔ͩΒ৽͍͠࢓ ༷ΛࢼͤΔͱ͔ɺ৽͍͠࢓༷Λࢼ͢ͷ͸ָ͍͠ͱ͍͏ଆ໘͕͋Δ ✦ ಉ༷ʹ IPv4 ӡ༻ΛॖখͰ͖ͨΒخ͍͠ͱ͍͏ଆ໘΋൱ఆ͸͠ͳ͍ ΠϕϯτωοτϫʔΫӡ༻ऀࢹ఺
39. ✦ IPv4 only, IPv4v6 dualstack ʹՃ͑ͯ IPv6 only + NAT64 ͱ͍ ͏઀ଓܗଶ͕ग़དྷΔҎ্ɺ୹ظతͳӡ༻ෛ୲͸௿͘͸ͳ͍ ✦ (ޙͰ৮ΕΔ͕) Apple device ͱ Android ͕ majority ͳ؀ڥͰ ͋Ε͹NAPT44 ઃඋͷधཁ͸ଈ࠲ʹ௿Լ͢ΔͨΊɺͦΕʹؾΛ ഑Δඞཁ͕ͳ͘ͳΔͱ͍͏఺Ͱ͸ෛ୲͸มΘΒͳ͍͔΋ ✦ NAT64 ઃඋͷӡ༻ܦݧ͕ઙ͍ͱ͔ͦ͏͍͏؍఺ͷ୹ظతෛ୲͸ ͋Δ͔΋͠Ε·ͤΜ ӡ༻͸ָʹͳΔ͔?
40. ✦ ܦࡁ໘ͩͱɺNAT44 ͱ NAT64 ͰઃඋΛ෼཭͢Δ৔߹͸ IPv4 ΞυϨείετ͸૿Ճ͢Δ ✦ NAPT44 ϓʔϧधཁ͕Ҡಈ͢Δ͸ͣͳͷͰΞυϨεΛ NAT64 ʹ Ҡ͢͜ͱ͸Ͱ͖ΔͩΖ͏͚Ͳ ✦ NAT64 ઃඋ͕ϙϐϡϥʔͰ͸ͳ͍ͱ͍͏೉఺΋͋Δ ✦ ҰํɺDNS64 ઃඋΛࣺͯΔ͜ͱ͸ग़དྷΔΑ͏ʹͳͬͨ ӡ༻͸ָʹͳΔ͔?
41. ✦ IPv6-mostly Λ only ʹ͍ͯ͘͠ IPv4 ؀ڥͷॖୀ͸՝୊ʹͳΔ͔΋ ✦ Backbone Λ v6 only ʹͨͯ͘͠΋ DHCPv4 Relay ͯ͠Δ͔Β… Έ͍ͨͳ໰୊͸࢒Γͦ͏ ӡ༻͸ָʹͳΔ͔?
42. RubyKaigi 2025 ͷ IPv6-mostly
43. ✦ ͓͠ͳ͕͖ ✦ NAT64 ✦ Pref64::/n ✦ DHCPv4 Option 108 ✦ τϥϒϧू IPv6-mostly at RubyKaigi
44. NAT64
45. ✦ طଘͷ battle-tested ͳ NAPT44 ઃඋ ͷԣʹ NAT64 ઃඋΛ௥Ճ ✦ طଘͷػࡐ͕ NAT64 ඇαϙʔτ ✦ τϥϒϧ࣌ʹ࣮੷͋Δ࣮֬ͳ setup ʹ fallback ͢ΔͨΊ ✦ ίΞL3εΠον → NAT{44,64} → ձ৔Τοδϧʔλʔ NAT64 at RubyKaigi: Summary EtherIP tunnel EtherIP over IPsec tunnel Both(EtherIP & EtherIP/IPsec) IPsec Tunnel Direct Link ※AS����[���]はAS�����には local-as �����として接続している AS����� AS����� AS����� AS����� AS���� AS����� AS����� AS�� L3 Diagram
46. ✦ NAT64 ػࡐ͸ Linux ͕ೖͬͨϛχ PC (N100) ✦ Linux mainline ʹ͸ Stateful NAT64 ࣮૷͕ͳ͍ (!) ✦ Jool ͳͲ֎෦ͷ kernel module + userspace ࣮૷͕ϙϐϡϥʔ ✦ ࠾༻ͨ͠ߏ੒͸ Linux net fi lter + ࣗલ࣮૷ + bird2 ✦ NAPT66: Linux net fi lter (nftables) ✦ NAT64 (SIIT): https://github.com/sorah/xlat ✦ Routing (BGP): bird2 NAT64 at RubyKaigi: Linux box
47. ✦ RubyKaigi ͳͷͰ? Ruby Ͱ࣮૷Ͱ͖ΔͷͰ͸ ✦ kazuho/rat (Ruby userspace ͷ NAPT44 ࣮૷) ͱ͍͏ઌߦࣄྫ ✦ Ͱ͖ͨ → https://github.com/sorah/xlat ✦ Acknowledgement: @hanazuki ͕ߴ଎ԽΛ΍ͬͯ͘Ε·ͨ͠ https://blog.kmc.gr.jp/entry/2025/05/13/130055 RubyKaigi 2 0 2 5 で使 用 したSIITのRuby実装について sorah/xlat
48. ✦ Linux mainline ʹ࣮૷͕ͳ͍ɺεςʔτϨεͳ IPv4/v6 ϔομͱ ICMPv4/v6 ύέοτม׵ (SIIT*) ͚࣮ͩ૷ ✦ NAPT ͸ Linux net fi lter ͷ NAPT66 ࣮૷Λར༻ ✦ Net fi lter ͷ NAPT44 ͸աڈʹ RubyKaigi Ͱӡ༻࣮͠੷͕͋Δ ✦ kernel Ͱ IPv6 addresses → IPv6 address ͷ N:1 ͳ NAPT SIIT ͸ IPv6 address ←→ IPv4 address ͷ NAT Λ͢Δ͚ͩ ✦ = NAPT66 + Stateless NAT64 ͷ߹੒Ͱ Stateful NAT64 ʹ sorah/xlat * RFC 7915: Stateless IP/ICMP Translation, RFC 6052: IPv6 Addressing of IPv4/IPv6 Translators
49. sorah/xlat SIIT net fi lter NAPTv6 Bird2 Upstream Router Downstream L3 Switch Ϣʔβଆ͔ΒΠϯλʔωοτ΁ͷܦ࿏ src={CLAT}/64 dst=Pref64::/n src={固定}/128 dst=Pref64::/n src={固定}/32 dst=IPv4アドレス (2) srcΛNAPTv6Ͱ୺຤ͷ/64 ͔Β/128ʹม׵ (3) IPv6 datagram Λ IPv4 datagram ʹม׵ src/dst ͸ Pref64::/n ʹຒΊࠐ·Εͨ IPv4 ΞυϨεʹ (1) ͜ͷઌͷ୺຤ (macOS౳) Ͱ ಈ࡞͢Δ CLAT ػೳ͕ Pref64::/n ʹ ѼઌIPv4ΞυϨεΛຒΊࠐΜͰ IPv6 datagramʹͨ͠ύέοτΛૹͬͯ͘Δ BGP (4)͜ͷઌ͸IPv4ͷੈք
50. ✦ ܦ࿏੍ޚ͸ BGP ✦ Pref64::/n ΁ͷܦ࿏Λ downstream (clientଆ) ʹ IPv4 outer ͷ /32 Λ upstream (internetଆ) ʹ޿ใ͍ͯ͠Δ ✦ ड͚औΔͷ͸ downstream ͔Β഑Լͷܦ࿏, upstream ͔Β 0/0 ܦ࿏੍ޚ
51. ✦ Downstream ͷܦ࿏දͰ͸ ECMP Ͱ৑௕ + ϩʔυόϥϯε ✦ Hash key Λ IPv6 saddr ʹߜͬͯ stickiness Λ࣮૷ ✦ ো֐/෮چ࣌͸ܦ࿏੾ସͰطଘͷ NAPT ηογϣϯ͸શ໓͢Δ ✦ Upstream ͷܦ࿏ද͸ IPv4 outer address /32 ✦ ;ͭ͏ ܦ࿏੍ޚ
52. ✦ BIRD Ͱ Pref64::/n Ѽͷ static route Λ recursive next hop, v4-via-v6 Ͱఆ͍ٛͯ͠Δ → upstream ͔Βͷ v4 default route ్͕੾ΕͨΒ downstream ΁ͷܦ࿏޿ใΛఀࢭ͢Δ ✦ Kernel FIBʹ͸ install ͠ͳ͍ BGP ޿ใ༻ͷܦ࿏σʔλ ܦ࿏੍ޚ protocol static static_bgp6 { … igp table bgp4; route 2001:df0:8500:ca64::/64 recursive 192.0.0.0 { bgp_community.add((C_SELF,C_CTL_ALLOW_INSIDE)); bgp_community.add((C_SELF,C_CTL_PREVENT_KERNEL)); }; } https://github.com/ruby-no-kai/rubykaigi-net/blob/master/itamae/roles/plat/templates/etc/bird/bird.conf.d/plat.conf
53. Pref64::/n
54. ✦ 464XLAT (RFC 6146) Ͱ͸ RFC 7915 (SIIT) Ͱར༻͢Δ v4/v6 ΞυϨεม׵ΞϧΰϦζϜ͸ RFC 6052 Λར༻͢Δͱఆٛ ✦ RFC 6052 § 3.1. Ͱ IPv4 private address Ͱ well-known pre fi x ͷར༻͕ېࢭ͞Ε͍ͯΔ*ͨΊɺࣗ෼Ͱ pre fi x ΛબͿඞཁ͕͋Δ ✦ ·ͨ § 4.1. ʹબͼํͷ1ͭͱͯ͠ checksum neutral ͷ঺հ͕͋Δ ✦ Pref64::/n ͷ 1 ͷิ਺࿨͕ ff f 16 ͳ͍͠ 000016 ʹ͓ͯ͘͠ → ΞυϨεม׵࣌ʹIPϔομͷνΣοΫαϜͷ࠶ܭࢉ͕ෆཁʹ Pref64::/n ͷબఆ * ͜ͷ੍ݶΛ؇࿨͢Δ I-D draft-ietf-v6ops-nat64-wkp-1918 ͕ͪΐ͏Ͳࠓ೔ WG adopt ͞ΕͨΑ͏
55. ✦ RA Option (RFC 8781) ͸ Junos 22.4R1 ͔ΒઃఆՄೳʹ (ϥοΩʔ) set protocols router-advertisement interface … nat-prefix … ✦ RFC 7050 (ipv4only.arpa AAAA Ϩίʔυ) ΋࣮૷͍͕ͯͨ͠ɺ ຊ൪Ͱ͸΄΅ RA ΦϓγϣϯΛݟΔ୺຤͕઎Ί͍ͯͨ(͸ͣ) ✦ DHCPv4αʔόʔͱൺֱͯ͠ϧʔλػثͰαϙʔτ͞Εͳ͍৔߹͸ σϓϩΠ͕ࠔ೉ͳঢ়گͳͷ͸ਏ͍ ✦ ઃఆͰ೚ҙͷΦϓγϣϯͱσʔλྻΛ௥ՃͰ͖ͯཉ͍͠… RDNSSͷࣄΛࢥ͍ग़͢ Pref64::/n Signalling
56. DHCP
57. ✦ RubyKaigi Ͱ͸௕೥ ISC Kea Λ DHCPv4 αʔόʔͱͯ͠ར༻ ✦ DHCPv4 Option 108 (RFC 8985: IPv6-only Preferred) ͸ Kea 2.7.1 ͔Βαϙʔτ͕ೖͬͨ ✦ ฦͨ͠৔߹ʹ DHCP ϦʔεΛলུ͢Δ ✦ ͦΕҎલͷόʔδϣϯͰ΋೚ҙͷΦϓγϣϯΛ௥ՃͰ͖ΔͨΊ Ϧʔεͷলུ͸Ͱ͖ͳ͍͕ૹ৴ࣗମ͸Մೳ DHCPv4 Option 108 (IPv6-only Preferred)
58. ✦ “Legacy” SSID Ͱ͸ Option 108 ΛΦϓτΞ΢τ͍ͨ͠ ✦ DHCP Relay ͕͚ͭΔ Option 82 Ͱ switchport ΍ SSID ΛऔΕΔ ✦ ͨͩɺSubnet Ͱఆٛͨ͠ option-data Λ client class Ͱ্ॻ͖ ग़དྷͳ͍ɻͦͷͨΊઃఆ͸ΦϓτΠϯํࣜͰߦ͏ Kea Ͱ Option 108 ͷ Scoping https://github.com/ruby-no-kai/rubykaigi-net/blob/master/k8s/dhcp/config/class_main_ssid.libsonnet { name: 'main_ssid', test: "(split(relay4[2].hex, ':', 2) == 'RubyKaigi 2025')" + // SSID " or (relay4[1].hex == 'cs-01-venue:ge-0/0/0.0:usr')", // switchport 'only-if-required': true, 'option-data': [{ name: 'v6-only-preferred', data: '1800' }], }
59. RubyKaigi 2025 Experiment Results
60. ✦ 2025/4 ͷ RubyKaigi 2025 Ͱࢼͨ͠ͱ͜Ζɺ͍͔ͭ͘τϥϒϧ͕ ͋ͬͨͷͰࣄྫΛ঺հ ✦ Majority ͕ Apple σόΠεͷͨΊ iOS, macOS ؔ࿈ͷ໰୊ ✦ 2025/9 ͷ Kaigi on Rails 2025 Ͱ͸ Apple ଆͷमਖ਼౳ʹΑΓɺ ೝ͍ࣝͯ͠Δ໰୊ͷຆͲ͸ղܾ ✦ macOS 15.5, iOS 15.5 (5݄) Ҏ͔߱ macOS 26, iOS 26 ͳΒ OK ✦ https://blog.sorah.jp/2025/11/04/mystery-of-clat-on-apple- devices ʹ΋·ͱ·͍ͬͯ·͢ Results of RubyKaigi 2025 experiment
61. Unicast Neighbor Solicitation ΁ͷԠ౴͕ͳ͍
62. ✦ ຊ൪ͷࡍɺApple device ͸઀ଓͯ͠ 30 ෼ఔ౓Ͱ IPv4 Internet ઀ଓੑΛࣦ͏͜ͱ͕෼͔ͬͨ ✦ CLAT͸ىಈ͍ͯ͠Δ͕ύέοτ͕ؼͬͯ͜ͳ͍ ✦ ຊ൪த͸෼͔Βͣɺޙ೔ௐࠪɻ։ൃ࣌͸ WLC Λ௨͍ͯ͠ͳ͔ͬͨ ͨΊɺWLC ༧උػΛར༻ͯ͠؀ڥΛ͞Βʹۙ෇͚ͯ௥ࢼ ✦ ௐࠪͷ݁Ռ First hop router Ͱ CLAT ͕࣋ͭ IPv6 ΞυϨεͷ Neighbor Discovery ʹࣦഊ͍ͯ͠Δ͜ͱ͕෼͔ͬͨ Losing IPv4 Internet reachability
63. ✦ Wi-Fi ؀ڥͰ͸ AP, Controller Ͱ ARP/ND ͷ୅ཧԠ౴͕͋Γ͕ͪ ✦ Multicast ύέοτΛݮΒͯ͠ Wi-Fi ΤΞλΠϜΛ࡟ݮ͢ΔͨΊ ✦ WLC ͷۙྡςʔϒϧͰ reachable ͳؒ͸ WLC ͕ unicast NS ʹ ୅ฦ͍ͯ͠Δ͕ɺλΠϚ͕੾ΕΔͱ unicast NS ʹ౴͑ͳ͘ͳΔ Neighbor Discovery Proxy Wireless Controller First hop Router Client (STA) Unicast NS Solicited NA (while reachable) Unicast NS No Response
64. ͜Ε͸ 2 ͭͷ Workaround ͕ߟ͑ΒΕΔ. RubyKaigi Ͱ͸ #1 Λ࠾༻ 1. ۙྡςʔϒϧͷ Lifetime ΛԆ௕͢Δ: ࠷େͷ΂ΫϥΠΞϯτ਺΍଺ࡏ࣌ؒɺػثͷ্ݶΛߟ͑ͳ͕Βઃఆ RubyKaigi Ͱ͸ 18 ࣌ؒʹ 2. Multicast NS ύέοτΛ Wi-Fi ΫϥΠΞϯτ΁సૹ͢Δ: Wi-Fi ͷΤΞλΠϜΛফඅ͢ΔͷͰ͓͢͢Ί͠ͳ͍ ·ͨɺIPv6 Ͱ stateful fi rewall ͕ͳ͍ͨΊɺΠϯλʔωοτ͔Β ಧ༷͘ʑͳύέοτʹΑͬͯ NS ύέοτ͕ੜ੒͞Εͯ͠·͏໰୊΋ No solicited NA: Workarounds
65. DNS Ͱىಈͨ͠ CLAT ͕ ແޮʹͳΔ
66. ✦ ipv4only.arpa ͷ AAAA ϨίʔυΛར༻ͯ͠ Pref64::/n Λݕग़͢Δ ํ๏΋ݕূ࣌͸ςετ͍ͯͨ͠ ✦ ࠶ݱ৚݅͸ϋοΩϦ͍ͯ͠ͳ͍͕εϦʔϓͳͲ͔Β໭ͬͯ͘Δͱ CLAT ͕ࢭ·ͬͯ͠·͏ͷ͔ IPv4 ઀ଓੑ͕ࣦΘΕΔ͜ͱ͕ ✦ ͦͷ৔߹Ͱ΋Ҿ͖ଓ͖ Option 108 ͸༗ޮͰ native IPv4 ʹ fallback ͠ͳ͍ ✦ ࠶ݱ͕͔͔࣌ؒΔɾ೉͍ͨ͠Ί macOS 26 Ͱͷ௥ࢼ͸Ͱ͖ͯͳ͍ ✦ RA PREF64 Λ࢖͍·͠ΐ͏ DNS-triggered CLAT disabled after resuming from sleep
67. ✦ Well known ͳ A Ϩίʔυ ipv4only.arpa (RFC 8880) Λఆٛͯ͠ɺ DNS64 ͕ಈ͍͍ͯΔ؀ڥͩͱ AAAA Ϩίʔυ͕ੜ੒͞Εͯ NAT64 pre fi x Λܭࢉ͢Δ͜ͱ͕Ͱ͖Δͱ͍͏࢓૊Έ ✦ ͨͩɺRFC 9872 Ͱ RFC 8781, RA ΦϓγϣϯͰͷ Pref64::/n γάφϦϯά͕ਪ঑͞Ε͍ͯΔ ิ଍: DNS based Pref64::/n discover is not encouraged
68. ✦ NAT64 pre fi x ʹରԠͨ͠Ϧκϧόʹґଘ࣮ͯ֬͠ੑ͕ͳ͍ ✦ ΧελϜϦκϧόΛ࢖ΘΕΔͱରԠෆՄɻϚϧνϗʔϜͰ΋໰୊ʹͳΓ͏Δ ✦ DNS Spoo fi ng ౳Ͱ IPv4 τϥϑΟοΫΛ༠ಋ͞Εͯ͠·͏ϦεΫ ✦ ղܾͨ͠ ipv4only.arpa Ϩίʔυͷ TTL ͕੾ΕΔ·Ͱߋ৽Ͱ͖ͳ͍ ✦ RAͳΒ࠶ૹ͢Δͱߋ৽Λϓογϡ͢Δ͜ͱ͕Մೳ L2υϝΠϯຖʹมߋ͢Δͷ΋༰қ ✦ Discovery ͕ऴΘͬͯ CLAT ͕ىಈ͢Δ·ͰͷϨΠςϯγ͕ߴ͍ ✦ IPv6 autocon fi guration ͷޙ DNS ΫΤϦΛͯ͠଴ͭͷͰ… RDNSSແ͍৔߹DHCPv6Λ଴ͭ͜ͱʹͳΓ͞Βʹ͔͔࣌ؒΔ DNS-based Discovery ͷओͳ໰୊఺ (from RFC 9872)
69. CLAT Internal Address Leakage
70. ✦ Apple ͷ CLAT ͸ local 192.0.0.1, peer 192.0.0.2 ͱͨ͠ link ͕࡞ ੒͞Εͯ peer (192.0.0.2) ͕ IPv4/v6 ύέοτม׵Λߦ͏ ✦ 192/29 ͸ RFC 7335 IPv4 Service Continuity Pre fi x ✦ Src 192.0.0.1 ͳύέοτ͕ MDNS, ICMP ౳Ͱ underlay ʹ࿙Εͯ ͘Δ໰୊ɻಉ͡ΞυϨεΛ࣋ͭ୺຤͕ෳ਺͍ΔΑ͏ʹݟ͑Δ ✦ Wi-Fi ؀ڥͩͱηΩϡϦςΟػೳͰ IP Theft ͱ൑அ͞Εͯ exclusion ͞ΕͨΓ͢Δ͜ͱ͕͋Δ CLAT Internal Address Leakage
71. ✦ ͜ͷ໰୊͸ APRICOT 2024 Wi-Fi ͷ writeup ౳Ͱใࠂ͞Ε͍ͯͨ ͨΊɺRubyKaigi 2025 ͷ࣌఺ͰࣄલʹରԠࡁ. ✦ Cisco WLC ͷ৔߹: ✦ IP Theft ͱ Reuse Λ Client Exclusion ͷର৅֎ʹઃఆ͢Δ config wps client-exclusion ip-theft disable ✦ ͨͿΜ࠷৽ͷ macOS/iOS Ͱ͸௚ͬͯΔ… Disable IP Theft https://blog.afrinic.net/apricot-ipv6-only#:~:text=Remaining%20issues%20were%20minor
72. Retry at Kaigi on Rails 2025
73. ✦ 2025/9 ͷ Kaigi on Rails 2025 Ͱ͜͜·Ͱͷ಺༰Λ౿·͑ͯ࠶ࢼ ߦ ✦ ݁Ռɺ֓Ͷ໰୊ͳ͠ ✦ Wi-Fi ΫϥΠΞϯτʹ IPv6 RA ͕ಧ͔ͣ઀ଓ͕ࣦΘΕΔ໰୊͸ ͕͋ͬͨຊ݅ͱؔ࿈͋Δ͔͸ෆ໌… Kaigi on Rails 2025
74. ✦ ҎԼͷ໰୊͸ macOS 15.5, iOS 18.5 ࠒ, ஗͘ͱ΋ macOS/iOS 26 Ͱ͸मਖ਼͞Ε͍ͯΔ ✦ No response to Unicast Neighbor Solicitations ✦ CLAT internal address leak ✦ No response to ICMPv6 Echo Requests ✦ IPv4 ΞυϨεͰ traceroute ͕Ͱ͖ͳ͍໰୊͸·ͩͷ͍ͬͯ͜Δ ✦ IPv6 ΞυϨεʹม׵͢Ε͹౰વՄೳ͚ͩͲ Kaigi on Rails 2025
75. ✦ 900 clients ✦ IPv4 ͷ 80% ఔ౓͕ NAT64 Λར༻ ✦ શମͷ 50-60% ͸ͦ΋ͦ΋ IPv6 Native (!) Kaigi on Rails 2025: Stats Kaigi on Rails ͸ RubyKaigi 2025 ʹൺ΂Δͱখن໛ (RubyKaigi ͸ 1,200-1,500 clients)
76. ✦ draft-ietf-v6ops-6mops-04 § 7.2. Ͱͷਪ঑΋͋Γɺ ରԠ͸ೖΕ͍ͯΔ͚Ͳ໰୊͕͔͋ͬͨͳ͍͔෼͔ͬͯͳ͍ͷ͸Լه ✦ IP Fragment ✦ QUIC ͸ MSS Clamping Ͱ͖ͳ͍Α 😎 ✦ ESP packet (IPsec) ✦ ಛʹ ESP ͸धཁ͕ͳ͍͔ɺ໰୊͕ใࠂ͞Ε͍ͯͳ͍͔͸෼͔Βͳ ͍ Extension Headers
77. ✦ v4→v6 ͷύέοτॲཧͷ͚࣌ͩϔομαΠζ͕૿͑ΔͨΊɺ v4 Internet → CLAT ͷ޲͖͚ͩ IPv4 MTU -20 ͱͳΔ ✦ ٯ͸ϔομ͕ॖΉͷͰߟ͑ͳͯ͘ྑ͍ ✦ RubyKaigi Ͱ͸ର֎઀ଓ͸τϯωϧͰ MTU ͕௿Ίʹઃఆ͞Ε͍ͯΔɻ v4 Internet ଆʹ͸ CLAT ଆͷ MTU ʹ͍ۙύέοτ͕དྷΔ͜ͱ͸ͳ͍ ✦ طʹFragment͞ΕͯΔ͔Fragmentation NeededΛ্ྲྀͰฦͯ͠Δ ✦ ͕ͨͬͯ͠ɺsorah/xlat Ͱ͸΍͖ͬͯͨύέοτΛ 2 ͭҎ্ʹ෼ׂ͸ ͠ͳ͍ɻFragment Header ͷ຋༁͚࣮ͩ૷ͨ͠ IP Fragment ΁ͷରԠ
78. ✦ sorah.jp が以下をお届けしました ✦ IPv 6 -mostly と IPv 6 移 行 技術 Recap ✦ RubyKaigi 2 0 2 5 , Kaigi on Rails 2 0 2 5 での運 用 実績 ✦ Many thanks: RubyKaigi NOC team members Outro https://github.com/ruby-no-kai/rubykaigi-net ←ίʔυ+ ϒϩά౳ϦϯΫू Slides ↓ https://speakerdeck.com/sorah/iw2025-rubykaigi-v6mostly