੐ᓟ౏㐿⾗ᢱ䋨⊒⴫ᤨ䈱ౝኈ䈎䉌ㅊട䊶ᦝᣂ䈅䉍䋩

ᢎ⑼ᦠ䈮䈲タ䈦䈩䈇䈭䈇DNS೽㗴䋺䉨䊞䉾䉲䊠DNS䉰䊷䊋䊷䈱ᘷ㝠
2013ᐕ7᦬19ᣣ
DNS Summer Days 2013ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴䋨JPRS䋩᫪ਅ ᵏብ@OrangeMorishita
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴1⻠Ꮷ⥄Ꮖ⚫੺• ᳁ฬ: ᫪ਅ ᵏብ䋨䉅䉍䈚䈢 䉇䈜䈵䉐䋩– 1965ᐕ9᦬21ᣣ↢䉁䉏䋨47ᱦ䋩↵ᕈ– ൕോవ䋺ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴– ⢋ᦠ: ᛛⴚᐢႎᜂᒰ• ᦨㄭ䈱㗿䈇䈗䈫䋺ᐔⓏή੐䈭7᦬– Ფᐕ㗿䈦䈩䈲ⵣಾ䉌䉏䈩䈇䉁䈜

Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴2ᧄᣣ䈱ౝኈ• ᤓᐕ䇮䈖䈖䈪䈖䉖䈭⹤䉕䈚䉁䈚䈢– 䈠䈱ਛ䈪䊶䊶䊶

Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴

3

DNS Summer Days 2012
䇸DNS౉㐷䇹䉋䉍ౣឝ㊀ⷐ䈭ᵈᗧ䋨1䋩• 䈖䈱䊌䊷䊃䈱䇸㽳䋺㓏ጀ᭴ㅧ䉕䈢䈬䉎䇹䈪⺑᣿䈜䉎䇸䈢䈬䉎䉰䊷䊋䊷䋨䋽䉨䊞䉾䉲䊠DNS䉰䊷䊋䊷䋩䇹䈱േ૞䈲䇮⃻ᤨὐ䈮䈍䈔䉎ታ㓙䈱䉅䈱䈫䈲৻ㇱ⇣䈭䈦䈩䈇䉁䈜䇯
• ․䈮䇮ᄖㇱฬ䋯ౝㇱฬ䈱䉼䉢䉾䉪䇮RFC 2181䈪
ቯ⟵䈘䉏䈩䈇䉎䊥䉸䊷䉴䊧䉮䊷䊄䈱ା㗬ᐲ䈱䉼䉢䉾䉪䈭䈬䇮ᧄ᧪ᔅⷐ䈫䈭䉎䈇䈒䈧䈎䈱੐㗄䈮䈧䈇䈩䇮ᗧ࿑⊛䈮⺑᣿䉕⋭⇛䈚䈩䈇䉁䈜䇯

Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴

4

DNS Summer Days 2012
䇸DNS౉㐷䇹䉋䉍ౣឝ㊀ⷐ䈭ᵈᗧ䋨2䋩• 䈠䈱⚿ᨐ䇮RFC 1034/1035䈏ᗧ࿑䈚䈢䈫⠨䈋䉌䉏䉎䉋䉍䉲䊮䊒䊦䈭䋨䈢䈣䈚䇮䉶䉨䊠䊥䊁䉞਄䈱⠨ᘦ䈏චಽ䈪䈲䈭䈇䋩േ૞⺑᣿䈫䈭䈦䈩䈇䉁䈜䇯• ੹࿁䇮ᗧ࿑⊛䈮⋭⇛䈚䈢ㇱಽ䈱േ૞⺑᣿䈮䈧䈇䈩䈲䇮䈇䈧䈎૗䉌䈎䈱ᒻ䋨⛯✬䋨䋿䋩䋩䈪ታᣉ䈪䈐䈢䉌䈇䈇䈭䈫⠨䈋䈩䈇䉁䈜䇯

Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴5ᧄᣣ䈱ౝኈ
• 䈫䈇䈉䈖䈫䈪䇮ᤓᐕ⋭⇛䈚䈢䇸ฬ೨⸃᳿䈮䈍䈔䉎䉨䊞䉾䉲䊠DNS䉰䊷䊋䊷䈱േ૞䇹䈮䈧䈇䈩䇮1.䉫䊦䊷䈫ౝㇱฬ䊶ᄖㇱฬ
2.ᆔછᖱႎ䈫referral
3.䉫䊦䊷䈲䉫䊦䊷䋨DNS䊂䊷䉺䈱䊤䊮䉨䊮䉫䋩
4.䉦䊚䊮䉴䉨䊷ဳ᡹᠄ᚻᴺ
䈫䈇䈦䈢䈅䈢䉍䈱䈍⹤䉕䈚䉁䈜
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴6੐೨䈱ᵈᗧ• ᧄᣣ䈱䈍⹤䈲䇮䉨䊞䉾䉲䊠DNS䉰䊷䊋䊷䈱േ૞䈱䇸䈗䈒৻ㇱ䇹䈮ㆊ䈑䉁䈞䉖• 䇸䉨䊞䉾䉲䊠DNS䉰䊷䊋䊷ጊ䇹䈲㜞䈒䈩㒾䈚䈇䈪䈜– ⑳䈮䉅䈠䈱㗂䈲⷗䈋䉁䈞䉖䋨䉋䈉䉇䈒৻ว⋡䈓䉌䈇䋿䋩• ᧄᣣ䈱䈍⹤䈲䇮䉼䊠䊷䊃䊥䉝䊦䈫䈚䈩䈲ዋ䈚㔍䈚䈇䈎䉅䈚䉏䉁䈞䉖䋨䈗䉄䉖䈭䈘䈇䋩– 䇸dig䉮䊙䊮䊄䈱಴ജ䉕⺒䉄䉎䇹䉕೨ឭ䈮䈚䈩䈇䉁䈜• ᧄᣣ䈱䈍⹤䈪䇮䇸䉨䊞䉾䉲䊠DNS䉰䊷䊋䊷䈱ᘷ㝠䇹䉕䇮䉂䈭䈘䉁䈮ዋ䈚䈪䉅౒ᗵ䈇䈢䈣䈔䉏䈳ᐘ䈇䈪䈜
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴7಴ജ଀䈮㑐䈜䉎ᵈᗧ• ᧄ⾗ᢱ䈪䈲dig䉮䊙䊮䊄䈱಴ജ଀䈭䈬䈮䈍䈇䈩ታ࿷䈜䉎䊄䊜䉟䊮ฬ䈱଀䉕⚫੺䈚䈩䈇䉁䈜䈏䇮䈠䉏䉌䈲ታ㓙䈱䉅䈱䈫䈲⇣䈭䉎႐ว䈏䈅䉍䉁䈜– ⺑᣿䈮ᡰ㓚䈏䈭䈇▸࿐䈪৻ㇱടᎿ䈚䈩䈇䉎႐ว䈏䈅䉍䉁䈜– ታ㓙䈱േ૞䈏ේⓂၫ╩ᤨ䈫䈲⇣䈭䈦䈩䈇䉎น⢻ᕈ䈏䈅䉍䉁䈜

Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴8

1.䉫䊦䊷䈫ౝㇱฬ䊶ᄖㇱฬ

Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴9䉋䈒䈅䉎⺑᣿• jp䈱䉰䊷䊋䊷䈲䊦䊷䊃䉰䊷䊋䊷䈫ห᭽䇸example.jp䈱䉰䊷䊋䊷䈮ᆔછ䈚䈩䈇䉁䈜䇹䈫䈇䈉ᔕ╵䉕㄰䈜
DNS Summer Days 2012䉼䊠䊷䊃䊥䉝䊦
䇸DNS౉㐷䇹䉋䉍ౣឝ䋨৻ㇱᡷ䋩䈖䈱ᔕ╵䊦䊷䊃䉰䊷䊋䊷䈱䊥䉴䊃䊦䊷䊃䉰䊷䊋䊷

䉨䊞䉾䉲䊠
DNS䉰䊷䊋䊷

䊡䊷䉱䊷

jp
䉰䊷䊋䊷

䊡䊷䉱䊷

example.jp
䉰䊷䊋䊷

kr
䉰䊷䊋䊷

example2.jp
䉰䊷䊋䊷

com
䉰䊷䊋䊷

org
䉰䊷䊋䊷

net
䉰䊷䊋䊷

example3.jp
䉰䊷䊋䊷

www
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴10䇸ᆔછ䈚䈩䈇䉁䈜䇹䈱ౝኈ• dig䉮䊙䊮䊄䈪⏕⹺䈚䈩䉂䉎– ᮭᆭDNS䉰䊷䊋䊷䈻䈱໧䈇ว䉒䈞䈪䈲ᔅ䈝+norec䉕䈧䈔䉎– ᦨㄭ䈱dig䋨BIND 9.9.0એ㒠䋩䈪䈲+noedns䉕䈧䈔䈭䈇䈫䇮
additional section䈱ᢙ䈏৻䈧ᄙ䈒䈭䉎䈱䈪ᵈᗧ• EDNS0䈱OPT⇼ૃ䊧䉮䊷䊄䈏ઃട䈘䉏䉎䈢䉄• ౖဳ⊛䈭಴ജ଀$dig+norec +noedns www.example.jp a@a.dns.jp…
;;flags:qr;QUERY:1,ANSWER:0, AUTHORITY:1,ADDITIONAL:1…
;;AUTHORITYSECTION:
example.jp.86400INNSns1.example.jp.
;;ADDITIONALSECTION:
ns1.example.jp.86400INA192.0.2.1
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴11ᆔછ䉕␜䈜ᔕ╵• ᮭᆭ䉕ᜬ䈢䈭䈇ᔕ╵䈪䇮answer section䈏ⓨ– ᮭᆭ䉕ᜬ䈢䈭䈇䋺flags䈮aa䈏฽䉁䉏䈩䈇䈭䈇– answer section䈏ⓨ䋺answer section䈱ᢙ䈏0• ᔕ╵䈏ઁ䈱䉰䊷䊋䊷䈻䈱ᆔછ䈪䈅䉎䈖䈫䉕␜䈜$dig+norec +noedns www.example.jp a@a.dns.jp…
;;flags:qr; QUERY:1,ANSWER:0, AUTHORITY:1,ADDITIONAL:1…
;;AUTHORITYSECTION:
example.jp.86400INNSns1.example.jp.
;;ADDITIONALSECTION:
ns1.example.jp.86400INA192.0.2.1
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴12ᆔછᖱႎ䈫䉫䊦䊷• authority section䈮ᆔછవ䈱NS䊖䉴䊃ฬ䉕㄰䈜• additional section䈮ᔅⷐ䈮ᔕ䈛䈩䇮NS䊖䉴䊃ฬ䈱IP䉝䊄䊧䉴䉕㄰䈜– 䈖䈱႐ว䈮㄰䈘䉏䉎A/AAAA䉕䉫䊦䊷䈫๭䈹$dig+norec +noedns www.example.jp a@a.dns.jp…
;;flags:qr;QUERY:1,ANSWER:0, AUTHORITY:1,ADDITIONAL:1…
;;AUTHORITYSECTION:
example.jp.86400INNSns1.example.jp.
;;ADDITIONALSECTION:
ns1.example.jp.86400INA192.0.2.1
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴13䉫䊦䊷䈫䇸䉫䊦䊷䇹• 䈚䈎䈚䇮䉫䊦䊷䈮⋧ᒰ䈜䉎૏⟎䈮䉶䉾䊃䈘䉏䉎
A/AAAA䋨એਅ䇸䉫䊦䊷䇹䈫⴫⸥䋩䈮䈲䇮ฃ䈔౉䉏䈩䉋䈇႐ว䈫ฃ䈔౉䉏䈩䈲䈇䈔䈭䈇႐ว䈏䈅䉎• એ㒠䇮ᧄ⾗ᢱ䈪䈲䇮– 䇸䉫䊦䊷䇹䋺ᆔછ䉕␜䈜ᔕ╵䈱additional section䈮
㄰䈘䉏䉎NS䊖䉴䊃ฬ䈱A/AAAA– 䉫䊦䊷䋺䇸䉫䊦䊷䇹䈱䈉䈤䇮authority section䈪ᜰቯ䈘䉏䈩䈇䉎NS䈏ౝㇱฬ䈪䈅䉎䉅䈱䈱ᗧ๧䈪૶↪䈚䉁䈜
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴14໧䋺䈖䈱䇸䉫䊦䊷䇹䈲ฃ䈔౉䉏䈩䉋䈇䈎䋿⠨䈋䈩䉂䉁䈚䉊䈉
$dig+norec +noedns www.example.jp a@a.dns.jp…
;;flags:qr;QUERY:1,ANSWER:0, AUTHORITY:1,ADDITIONAL:1…
;;AUTHORITYSECTION:
example.jp.86400INNSns1.example.net.
;;ADDITIONALSECTION:
ns1.example.net.86400INA192.0.2.1
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴15╵䋺ฃ䈔౉䉏䈩䈲䈇䈔䈭䈇• ᆔછవNS䈏ᄖㇱฬ䈪䈅䈦䈢႐ว䇮䇸䉫䊦䊷䇹䉕ฃ䈔౉䉏䈩䈲䈇䈔䈭䈇• 䈪䈲䇮ᄖㇱฬ䈪䈅䈦䈢႐ว䇮䈭䈟ฃ䈔౉䉏䈩䈲䈇䈔䈭䈇䈱䈎䋿
$dig+norec +noedns www.example.jp a@a.dns.jp…
;;flags:qr;QUERY:1,ANSWER:0, AUTHORITY:1,ADDITIONAL:1…
;;AUTHORITYSECTION:
example.jp.86400INNSns1.example.net.
;;ADDITIONALSECTION:
ns1.example.net.86400INA192.0.2.1
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴16䉋䈒䈅䉎⺑᣿䋨ਇචಽ䋺⑳䉅䉋䈒䈜䉎䋩• ns1.example.net㸢192.0.2.1䈫䈇䈉ኻᔕ䈮䈧䈇䈩䇮a.dns.jp䈲ᮭᆭ䉕ᜬ䈦䈩䈇䈭䈇• 䈧䉁䉍䇮ታ㓙䈮䈲⇣䈭䈦䈩䈇䉎䈎䉅䈚䉏䈭䈇– 䈎䈧䈩ታ㓙䈮᡹᠄䈮૶↪䋨alternic.net䈻䈱⺃ዉ䋩$dig+norec +noedns www.example.jp a@a.dns.jp…
;;flags:qr;QUERY:1,ANSWER:0, AUTHORITY:1,ADDITIONAL:1…
;;AUTHORITYSECTION:
example.jp.86400INNSns1.example.net.
;;ADDITIONALSECTION:
ns1.example.net.86400INA192.0.2.1
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴17䈪䉅䊶䊶䊶• 䇸ᮭᆭ䉕ᜬ䈦䈩䈇䈭䈇䇹䈫䈇䈉䈖䈫⥄૕䈲䇮ᆔછవ䈏ౝㇱฬ䈪䈅䉎႐ว䉅ห᭽– flags䈮aa䋨ᮭᆭ䉕ᜬ䈧ᔕ╵䋩䈲䉶䉾䊃䈘䉏䈩䈇䈭䈇䋣• 䈪䈲䇮ౝㇱฬ䈫ᄖㇱฬ䈪䈲૗䈏㆑䈉䈱䈎䋿$dig+norec +noedns www.example.jp a@a.dns.jp…
;;flags:qr;QUERY:1,ANSWER:0,AUTHORITY:1,ADDITIONAL:1…
;;AUTHORITYSECTION:
example.jp.86400INNSns1.example.jp.
;;ADDITIONALSECTION:
ns1.example.jp.86400INA192.0.2.1
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴18

䈠䉅䈠䉅ౝㇱฬ䈫䈲૗䈎䋿• ᆔછవ䈫䈚䈩ᜰቯ䈚䈢NS䈱ฬ೨䈏䇮ᆔછవ䈱䉹䊷䊮䈱ౝ஥䈱ฬ೨䈣䈦䈢႐ว䇮ౝㇱฬ䋨inbailiwick name䋩䈫๭䈳䉏䉎– ⷫ䋨ᆔછర䋩䈪䈲䈭䈒䇮ᆔછవ䈱䉹䊷䊮䈪⠨䈋䉎• ౝㇱฬ䈱଀$ORIGINjp.
@86400INSOA…
example.jp.
86400INNSns1.example.jp.

䈖䈱䉹䊷䊮䈱ౝ஥䈱ฬ೨䈖䈱ฬ೨䈏䊶䊶䊶

Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴19ౝㇱฬ䈮䈧䈇䈩䈱䉋䈒䈅䉎⺋⸃䋨1䋩• 㬍ᆔછర䉹䊷䊮䈱ౝㇱ䈱ฬ೨䈲䈜䈼䈩ౝㇱฬ– ౝㇱฬ䈎䈬䈉䈎䈲ᆔછర䈱䉹䊷䊮䈪䈲䈭䈒䇮ᆔછవ䈱䉹䊷䊮䈮䉋䈦䈩᳿䉁䉎• 䈧䉁䉍䇮એਅ䈱଀䈲䈇䈝䉏䉅ౝㇱฬ䈪䈲䈭䈇
$ORIGINjp.
@86400INSOA…
example.co.jp. 86400INNSns1.example.ne.jp.
$ORIGINjp.
@86400INSOA…
example.jp.
86400INNSns1.example.ne.jp.
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴20੐ᓟ⾗ᢱ䈪ㅊടౝㇱฬ䈮䈧䈇䈩䈱䉋䈒䈅䉎⺋⸃䋨2䋩
• 㬍䊦䊷䊃䉹䊷䊮ౝ䈱ᆔછ䈲䈜䈼䈩ౝㇱฬᛒ䈇䈮䈭䉎– 䈖䈱⺋⸃䉕䈚䈩䈇䉎ੱ䈲䈎䈭䉍ᄙ䈇䈪䈜– ታ㓙䈱ᔕ╵䈏䇸䉫䊦䊷䇹䉕㄰䈜䈖䈫䉅ℂ↱䈱৻䈧䈎䉅• 䊦䊷䊃䉹䊷䊮䈪䈅䈦䈩䉅ౝㇱฬ䊶ᄖㇱฬ䈱඙೎䈲䇮ઁ䈱䉹䊷䊮䈫ห᭽䋨ਅ⸥䈱଀䉕ෳᾖ䋩
$ORIGIN.
@86400INSOA…
jp.
86400INNSa.dns.jp.

䋨ౝㇱฬ䋩$ORIGIN.
@86400INSOA…
com.
86400INNSa.gtldŞservers.net.

䋨ᄖㇱฬ䋩

Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴21໧䋺䈖䉏䉌䈲ౝㇱฬ䈎ᄖㇱฬ䈎䋿⠨䈋䈩䉂䉁䈚䉊䈉
$ORIGINjp.
@86400INSOA…
䋨1䋩 example.jp.86400INNSns1.example.jp.
䋨2䋩 example.jp.86400INNSa.ns1.example.jp.
䋨3䋩 example2.jp.86400INNSns1.example.com.䋨4䋩 example3.jp.86400INNSns1.example.jp.
䋨5䋩 example.co.jp.86400INNSns1.example.co.jp.
䋨6䋩 example.ne.jp.86400INNSns1.example.ad.jp.
䋨7䋩 example4.jp.86400INNSns1.example.or.jp.
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴22╵䋺એਅ䈱ㅢ䉍• ౝㇱฬ䋺 䋨1䋩 䋨2䋩 䋨5䋩• ᄖㇱฬ䋺 䋨3䋩 䋨4䋩 䋨6䋩 䋨7䋩
$ORIGINjp.
@86400INSOA…
䋨1䋩 example.jp.
86400INNSns1.example.jp.
䋨2䋩 example.jp.
86400INNSa.ns1.example.jp.
䋨3䋩 example2.jp.86400INNSns1.example.com.䋨4䋩 example3.jp.86400INNSns1.example.jp.
䋨5䋩 example.co.jp. 86400INNSns1.example.co.jp.
䋨6䋩 example.ne.jp.86400INNSns1.example.ad.jp.
䋨7䋩 example4.jp.86400INNSns1.example.or.jp.
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴23ή᧦ઙ䈮䉫䊦䊷䉕ฃ䈔౉䉏䈩䉋䈇䈱䈲ౝㇱฬ䈱႐ว䈱䉂• ᆔછవ䈱NS䈏ౝㇱฬ䈪䈅䈦䈢႐ว䇮ᆔછవ䈱䉹䊷䊮䉁䈢䈲䈠䈱ౝ஥䈱䉹䊷䊮䈏䇮NS䈫䈚䈩ᜰቯ䈘䉏䈢ฬ೨䈮ኻ䈜䉎ᮭᆭ䉕ᔅ䈝ᜬ䈦䈩䈇䉎• 䈠䈱䈢䉄䇮ฃ䈔ข䈦䈢䉫䊦䊷䉕৻ᤨ⊛䈮ା↪䈚䈩䉹䊷䊮䉕䈢䈬䈦䈩䈇䈔䈳䇮䈇䈝䉏䈲䈠䈱ฬ೨䈮ኻ䈚ᮭᆭ䉕ᜬ䈧䋨ᧄᒰ䈮ା↪䈪䈐䉎䋩ᮭᆭ
DNS䉰䊷䊋䊷䈮ᔅ䈝಴ળ䈋䉎• 䈠䈱䈢䉄䇮ฬ೨⸃᳿䈮䈍䈇䈩ή᧦ઙ䈮䉫䊦䊷䉕ฃ䈔౉䉏䈩䉋䈇
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴24

䈧䉁䉍䇮ㅒ䈱┙႐䈎䉌⸒䈉䈫…
• ᆔછవ䈱NS䈏ᄖㇱฬ䈪䈅䈦䈢႐ว䇮ᆔછవ䈪
䈠䈱NS䈱ฬ೨䈮ኻ䈚ᮭᆭ䉕ᜬ䈧ᮭᆭDNS䉰䊷䊋䊷䈮಴ળ䈋䉎䈫䈲㒢䉌䈭䈇– ஧ὼ಴ળ䈋䉎䈖䈫䉅䈅䉎• ᆔછవ䈏䈢䉁䈢䉁䈠䈱ᄖㇱฬ䉅▤ℂ䈚䈩䈇䈢႐ว• 䈠䈱䈢䉄䇮䈠䈱႐ว䈱䇸䉫䊦䊷䇹䈲ฃ䈔౉䉏䈩䈲䈇䈔䈭䈇– ฃ䈔౉䉏䈩䉋䈇႐ว䉅䈅䉎䈏䇮䈠䈱್ቯ䈲㔍䈚䈇

Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴25

䇸䉫䊦䊷䇹䈏ઃ䈒᧦ઙ• ᦨㄭ䈱ᮭᆭDNS䉰䊷䊋䊷䋨BIND 9䇮NSD䈭䈬䋩䈱ታⵝ䈪䈲䇮ᄖㇱฬ䈱䇸䉫䊦䊷䇹䈲䈪䈐䉎䈣䈔ઃ䈔䈭䈇䉋䈉䈮േ૞䈜䉎– ㅍ䉌䉏䈩䉅䇸ᔃ䈅䉎䇹䉨䊞䉾䉲䊠䈲ᝥ䈩䉎– 䈧䉁䉍䇮ή㚝䈭䊂䊷䉺䈫䈭䉎• 䈢䈣䈚䇮ታⵝ䈮䉋䈦䈩䈲䇸䈠䈱ᮭᆭDNS䉰䊷䊋䊷ౝ䈮䈍䈇䈩䇮ઁ䈱ᆔછᖱႎ䈎䉌䉫䊦䊷䈫䈚䈩ෳᾖ䈘䉏䈩䈇䉎A/AAAA䈲ᄖㇱฬ䈪䈅䈦䈩䉅䇸䉫䊦䊷䇹䈫䈚䈩ઃ䈔䉎䇹䈫䈇䈉േ૞䉕䈜䉎䈱䈪ᵈᗧ
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴26

䇸䉫䊦䊷䇹䈱଀• www.iij.ad.jp• www.iij-ii.co.jp• www.iij4u.or.jp…䈱䇮䈠䉏䈡䉏䈱A䉕JP DNS䉰䊷䊋䊷䈮໧䈇ว䉒䈞䈢㓙䈱䇮⃻⁁䈮䈍䈔䉎䇸䉫䊦䊷䇹䈱ઃ䈐ᣇ䉕⷗䈩䉂䉁䈚䉊䈉

Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴27

䇸䉫䊦䊷䇹䈱଀䋨⛯䈐䋩
• www.iij.ad.jp䈱଀• ౝㇱฬ䈭䈱䈪䉫䊦䊷䈏ઃ䈒$dig+norec +noedns www.iij.ad.jp a@a.dns.jp…
;;flags:qr;QUERY:1,ANSWER:0,AUTHORITY:2,ADDITIONAL:4;;QUESTIONSECTION:;www.iij.ad.jp.INA;;AUTHORITYSECTION:
iij.ad.jp.86400INNSdns0.iij.ad.jp.
iij.ad.jp.86400INNSdns1.iij.ad.jp.
;;ADDITIONALSECTION:
dns0.iij.ad.jp.86400INA210.138.174.16
dns0.iij.ad.jp.86400INAAAA2001:240:bb41:8002::1:16
dns1.iij.ad.jp.86400INA210.138.175.5
dns1.iij.ad.jp.86400INAAAA2001:240:bb4c:8000::1:5
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴28

䇸䉫䊦䊷䇹䈱଀䋨⛯䈐䋩
• www.iij-ii.co.jp䈱଀• ᄖㇱฬ䈭䈱䈪䉫䊦䊷䈲ઃ䈎䈭䈇$dig+norec +noedns www.iijŞii.co.jp a@a.dns.jp…
;;flags:qr;QUERY:1,ANSWER:0,AUTHORITY:2,ADDITIONAL:0;;QUESTIONSECTION:;www.iijŞii.co.jp.INA;;AUTHORITYSECTION:
iijŞii.co.jp.86400INNSdnsŞb.iij.ad.jp.
iijŞii.co.jp.86400INNSdnsŞc.iij.ad.jp.

Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴29䇸䉫䊦䊷䇹䈱଀䋨⛯䈐䋩
• www.iij4u.or.jp䈱଀• ᄖㇱฬ䈣䈏䇮iij.ad.jp䈎䉌ෳᾖ䈘䉏䈩䈇䉎䈢䉄䇸䉫䊦䊷䇹䈏ઃ䈒$dig+norec +noedns www.iij4u.or.jp a@a.dns.jp…
;;flags:qr;QUERY:1,ANSWER:0,AUTHORITY:2,ADDITIONAL:4;;QUESTIONSECTION:;www.iij4u.or.jp.INA;;AUTHORITYSECTION:
iij4u.or.jp.86400INNSdns0.iij.ad.jp.
iij4u.or.jp.86400INNSdns1.iij.ad.jp.
;;ADDITIONALSECTION:
dns0.iij.ad.jp.86400INA210.138.174.16
dns0.iij.ad.jp.86400INAAAA2001:240:bb41:8002::1:16
dns1.iij.ad.jp.86400INA210.138.175.5
dns1.iij.ad.jp.86400INAAAA2001:240:bb4c:8000::1:5
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴30䈖䈱േ૞䈱ℂ↱䋨⑳䈱ផ᷹䋩• 䈠䈱䋨ᆔછᖱႎ䈫䈚䈩ᜰቯ䈘䉏䈢䋩ฬ೨䈏ౝㇱฬ䈫䈚䈩ᛒ䉒䉏䈩䈇䉎䈖䈫䉕䇮⑳䋨ᆔછర䈱ᮭᆭ
DNS䉰䊷䊋䊷䋩䈲⍮䈦䈩䈇䉎• 䈪䈅䉏䈳䇮⑳䈏䈠䉏䉕䇸䉫䊦䊷䇹䈫䈚䈩㄰䈚䈩䉅ታኂ䈲䈭䈇䈲䈝䈪䈅䉎䋨቟ోᕈ䉕៊䈭䉒䈭䈇䋩• 䈠䈚䈩䇮䈠䉏䉌䉕䇸䉫䊦䊷䇹䈫䈚䈩㄰䈜䈖䈫䈮䉋䉍䇮ฬ೨⸃᳿䈱ല₸䈏⦟䈒䈭䉍䈉䉎– ታ㓙䈮䈠䈉䈚䈢䉬䊷䉴䈲⿠䈖䉍䈉䉎䈠䉏䈭䉌䇮䇸䉫䊦䊷䇹䉕ઃ䈔䈩䈅䈕䉎䈖䈫䈮䈚䉁䈚䉊䈉
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴31૛⸘䈭䈍਎⹤䋿• 䈚䈎䈚䇮䈖䈱േ૞䈲䉫䊦䊷䈫ౝㇱฬ䊶ᄖㇱฬ䈮ኻ䈜䉎ℂ⸃䉕ᅹ䈕䉎ේ࿃䈫䈭䈦䈩䈇䉎䈫䉅⸒䈋䉎• 䈎䈧䇮䈖䈱േ૞䋨DNS䊒䊨䊃䉮䊦䈫䈚䈩᣿⏕䈮ቯ⟵䈘䉏䈩䈇䈭䈇䋩䈮ଐሽ䈚䈢NS⸳ቯ䈏಴࿁䉎䈖䈫䈮䉅䈭䉍䇮዁᧪䈱⑒ᩮ䈫䈭䉎น⢻ᕈ䈏䈅䉎– ታⵝ䉕ᄌᦝ䈚䈢㓙䈮ฬ೨䈏ᒁ䈔䈭䈒䈭䉎䈭䈬• 䈧䉁䉍䇸૛⸘䈭䈍਎⹤䇹䈪䈅䉎䈫䉅⸒䈋䉎

Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴32䈖䈱䊌䊷䊃䈱䉁䈫䉄䋨1/2䋩
• 䉫䊦䊷䈫䇸䉫䊦䊷䇹䈱㆑䈇– 䇸䉫䊦䊷䇹䋨䈖䈱䉼䊠䊷䊃䊥䉝䊦⁛⥄䈱ቯ⟵䋩䋺ᆔછ䉕␜䈜ᔕ╵䈱additional section䈮㄰䈘䉏䉎NS䊖䉴䊃ฬ䈱A/AAAA– 䉫䊦䊷䋨৻⥸⊛䈭ቯ⟵䋩䋺䇸䉫䊦䊷䇹䈱䈉䈤䇮authority section䈪ᜰቯ䈘䉏䈩䈇䉎NS䈏ౝㇱฬ䈪䈅䉎䉅䈱– 䇸䉫䊦䊷䇹䈱䈉䈤䉫䊦䊷䈪䈭䈇䉅䈱䉕䇸䉫䊦䊷䉅䈬䈐䇹䋨pseudo-glue䋩䈫๭䈹ᵹ௾䉅䈅䉎䋨৻⥸⊛䈭ቯ⟵䈪䈲䈭䈇䈱䈪ᵈᗧ䋩
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴33

䈖䈱䊌䊷䊃䈱䉁䈫䉄䋨2/2䋩• ౝㇱฬ䈱ቯ⟵– ᆔછవ䈫䈚䈩ᜰቯ䈚䈢NS䈱ฬ೨䈏䇮ᆔછవ䈱䉹䊷䊮䈱ౝ஥䈱ฬ೨䈣䈦䈢႐ว– ή᧦ઙ䈮䉫䊦䊷䉕ฃ䈔౉䉏䈩䈇䈇䈱䈲䇮ౝㇱฬ䈱ᤨ䈣䈔• 䇸䉫䊦䊷䉅䈬䈐䇹䉕ઃ䈔䉎ᮭᆭDNS䉰䊷䊋䊷– ᮭᆭDNS䉰䊷䊋䊷䈱ታⵝ䈮䉋䈦䈩䈲᧦ઙ䈮䉋䉍䇮ᄖㇱฬ䈱႐ว䈪䈅䈦䈩䉅䇸䉫䊦䊷䉅䈬䈐䇹䉕ઃ䈔䉎䈖䈫䈏䈅䉎䈱䈪ⷐᵈᗧ
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴34

2.ᆔછᖱႎ䈫referral

Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴35ᆔછᖱႎ䈫referral• referral䋨ෳᾖ䋩䈫䈲– ໧䈇ว䉒䈞䈮ኻ䈚ઁ䈱䉰䊷䊋䊷䉕᩺ౝ䈜䉎䈖䈫• ᆔછᖱႎ䈫referral– ᮭᆭDNS䉰䊷䊋䊷䈲referral䉕↪䈇䈩ᆔછ䉕␜䈜– ଀䇸example.jp䉹䊷䊮䈲ns1.example.jp䈮ᆔછ䈚䈩䈇䉁䈜䇹$dig+norec +noedns www.example.jp a@a.dns.jp…
;;flags:qr; QUERY:1,ANSWER:0, AUTHORITY:1,ADDITIONAL:1…
;;AUTHORITYSECTION:
example.jp.86400INNSns1.example.jp.
;;ADDITIONALSECTION:
ns1.example.jp.86400INA192.0.2.1
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴36▤ℂᄖ䈱䉹䊷䊮䈮ኻ䈜䉎໧䈇ว䉒䈞• 䈠䈱ᮭᆭDNS䉰䊷䊋䊷䈱▤ℂᄖ䈱ฬ೨䉕໧䈇ว䉒䈞䈢႐ว䈱േ૞䈏໧㗴䈫䈭䉎– ⥄り䉁䈢䈲⥄り䈱ᆔછవ䈪䈲䈭䈇ฬ೨– ଀䋺JP DNS䉰䊷䊋䊷䈮ኻ䈜䉎ns1.example.com• ㅢᏱ䈱ฬ೨⸃᳿䈪䈲ታᣉ䈘䉏䈭䈇

Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴37

䇸Upward referrals䈲᦭ኂ䇹䋨Upward Referrals Considered Harmful䋩• DNS-OARC䈏2009ᐕ䈮౏㐿䈚䈢ᢥᦠ
Upward Referrals Considered Harmful<https://www.dns-oarc.net/oarc/articles/upward-referrals-consideredharmful>• NANOG 45䈱⊒⴫⾗ᢱ“Upward Referrals Considered Harmful” – Peter Losher<http://www.nanog.org/meetings/nanog45/presentations/Wednesday/Losher_light_harmful_N45.pdf>

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Upward referrals䈫䈲䋿䋨⛯䈐䋩• BIND 9䈪䈲ౣᏫᬌ⚝ⷐ᳞䈱ฃ䈔ઃ䈔䉕ήല䈮䈚䈩䈇䉎䋨recursionno;䋩䉰䊷䊋䊷䈮▤ℂᄖ䈱ฬ೨䉕໧䈇ว䉒䈞䈢႐ว䇮䊦䊷䊃䉰䊷䊋䊷䈻䈱referral䉕㄰䈜
– BIND 8䈪䈲䇸䉫䊦䊷䇹䉅㄰䈜• Upward referrals䈱଀$dig+norec +noedns www.example.jp a@䈫䈅䉎ᮭᆭDNS䉰䊷䊋䊷…
;;flags:qr;QUERY:1,ANSWER:0,AUTHORITY:13,ADDITIONAL:0;;AUTHORITYSECTION:.
518400 IN.
518400 IN…

NSNSa.rootŞservers.net.
b.rootŞservers.net.

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Upward referrals䈫䈲䋿䋨⛯䈐䋩• 䈖䈱ᔕ╵䋨਄૏䉹䊷䊮䈻䈱referral䋩䈲䇮ᆔછ䈫ห䈛ᒻ䉕䈚䈩䈇䉎䈏䇮ᆔછ䈪䈲䈭䈇• 䈖䈱ᔕ╵䈱ᗧ๧䋨⑳䈱ផ᷹䋺䉿䊮䊂䊧㘑䈮䋩– 䇸䈖䉏䇮⑳䈏▤ℂ䈚䈩䈭䈇䉹䊷䊮䈻䈱໧䈇ว䉒䈞䈰䇯䈣䈎䉌䈾䉖䈫䈲ήⷞ䈚䈩䉅䈇䈇䉖䈣䈎䉌䇯䇹– 䇸䈪䉅․೎䈮ᢎ䈋䈩䈅䈕䉎䇯䈅䈭䈢䈲䊦䊷䊃䉰䊷䊋䊷䈮⡞䈔䈳䈇䈇䈱䇯䉰䊷䊋䊷䈱৻ⷩ䈲䈖䉏䈰䇯䇹– 䇸䉒䈎䈦䈢䋿䈞䈦䈎䈒ⷫಾ䈮ᢎ䈋䈩䈅䈕䈢䉖䈣䈎䉌䇮䉅䈉䈖䈖䈮᧪䈤䉆䈣䉄䉋䇯䇹
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴40䈖䈱ᔕ╵䈱ᩮ᜚• RFC 1034䈮䈍䈔䉎એਅ䈱⸥ㅀ䈏䇮䈖䈱ᔕ╵䈱ᩮ᜚䈫䈭䈦䈩䈇䉎䈫⠨䈋䉌䉏䉎
4.3.1.Queriesandresponses…
Thewaythatthenameserveranswersthequerydependsuponwhetheritisoperatinginrecursivemodeornot:Ş ThesimplestmodefortheserverisnonŞrecursive,sinceit
cananswerqueriesusingonlylocalinformation:theresponsecontainsanerror,theanswer,orareferraltosomeotherserver“closer” totheanswer.䋨ᔕ╵䈲䉣䊤䊷䇮ᔕ╵䇮䈅䉎䈇䈲䇸䉋䉍ㄭ䈇䇹䉰䊷䊋䊷䈻䈱referral䉕฽䉃䋩

Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴41੹䈫䈭䈦䈩䈲૛⸘䈭䈍਎⹤• Upward referrals䉕㄰䈘䉏䈩䉅䇮䉨䊞䉾䉲䊠DNS䉰䊷䊋䊷䈲ᝥ䈩䉎䈚䈎䈭䈇– ᆔછᖱႎ䈪䈲䈭䈇– 䊦䊷䊃䉰䊷䊋䊷䈱৻ⷩ䈲䈠䉅䈠䉅ᜬ䈦䈩䈇䉎• 䈎䈧䇮DNS䊥䊐䊧䉪䉺䊷᡹᠄䈱ర䊈䉺䈮䈭䉍䈉䉎– “. IN NS”䈱໧䈇ว䉒䈞䋺47䊋䉟䊃– 䈠䈱ᔕ╵䋨Upward referrals䋩䋺256䊋䉟䊃• ታ㓙䈱᡹᠄଀䈅䉍– ☨࿖䊖䉴䊁䉞䊮䉫ડᬺISPrime␠• “Upward Referrals Considered Harmful”䈮䈅䉎ታ଀
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Upward referrals䉕಴䈘䈭䈇⸳ቯ• BIND 9– additionalŞfromŞcacheno;䉕ᜰቯ䇮䉁䈢䈲
allowŞqueryŞcache{none;};䉕ᜰቯ• BIND 9䈲䈖䈱䊂䊷䉺䉕䊦䊷䊃䊍䊮䊃䈫䈚䈩ᜬ䈦䈩䈇䉎• 䊦䊷䊃䊍䊮䊃䈲䊒䊤䉟䊚䊮䉫䈮䉋䉍౉ᚻ䈚䈢䉨䊞䉾䉲䊠䊂䊷䉺– named.root䉕ᶖ䈚䈢䈣䈔䈪䈲ലᨐ䈏䈭䈇䈱䈪ᵈᗧ• ౝㇱ䈮䊊䊷䊄䉮䊷䊂䉞䊮䉫䈘䉏䈩䈇䉎– 䈖䈱⸳ቯ䈮䉋䉍䇮REFUSED䉕㄰䈜䉋䈉䈮䈭䉎$dig+norec +noedns www.example.jp a@䈫䈅䉎ᮭᆭDNS䉰䊷䊋䊷…
;;Ş>>HEADER<<Ş opcode:QUERY,status:REFUSED,id:xxxxx;;flags:qr;QUERY:1,ANSWER:0,AUTHORITY:0,ADDITIONAL:0
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43

Upward referrals䉕಴䈘䈭䈇⸳ቯ• NSD䋺⸳ቯਇⷐ– ▤ℂᄖ䈱䉹䊷䊮䈮ኻ䈜䉎໧䈇ว䉒䈞䈮䈲䇮䊂䊐䉤䊦䊃䈪SERVFAIL䉕㄰䈜• PowerDNS䋺⸳ቯਇⷐ– 䊂䊐䉤䊦䊃䈪send-root-referral=no䈫䈭䈦䈩䈇䉎– yes䋨BIND 8੕឵䋩䉇lean䋨BIND 9੕឵䋩䈮⸳ቯน⢻• djbdns䋺⸳ቯਇⷐ– ▤ℂᄖ䈱䉹䊷䊮䈮ኻ䈜䉎໧䈇ว䉒䈞䈮䈲ᔕ╵䈚䈭䈇
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴44૛⺣䋺䈭䈟䊦䊷䊃䊍䊮䊃䈏䋿• ᮭᆭDNS䉰䊷䊋䊷ኾ↪䈱BIND 9䈱䈲䈝䈭䈱䈮䇮䈭䈟䊦䊷䊃䊍䊮䊃䈏ᔅⷐ䈮䈭䉎䈱䈎䋿• ╵䋺NOTIFY䊜䉾䉶䊷䉳䈱ㅍାవ䉕⺞䈼䈩䈇䉎– BIND 9䈱䊒䊤䉟䊙䊥䉰䊷䊋䊷䈲䇮䉹䊷䊮䊐䉜䉟䊦䈱
ᦝᣂᤨ䈮NOTIFY䊜䉾䉶䊷䉳䉕䉶䉦䊮䉻䊥䉰䊷䊋䊷⟲䈮ㅍା䈜䉎

• 䈖䈱䇸䉶䉦䊮䉻䊥䉰䊷䊋䊷⟲䇹䈱IP䉝䊄䊧䉴䉕䇮䊒䊤䉟䊙䊥䉰䊷䊋䊷䈱BIND 9䈲䈬䈉䉇䈦䈩⺞䈼䈩䈇䉎䈱䈎䋿
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴45੐ᓟ⾗ᢱ䈪ᦝᣂ䋨⣀ᒙᕈ䈻䈱⸒෸䋩૛⺣䋺䈭䈟䊦䊷䊃䊍䊮䊃䈏䋿䋨⛯䈐䋩• BIND 9䈱䊒䊤䉟䊙䊥䉰䊷䊋䊷䈲named.conf䈪
NOTIFY䈱ㅍ䉍వ䉕೎ㅜᜰቯ䈚䈩䈇䈭䈇႐ว䇮એਅ䈱䉋䈉䈮േ૞䈜䉎㽲 ⥄ಽ䈏▤ℂ䈜䉎䉹䊷䊮䈱NS RRSet䉕⺞䈼䉎㽳 㽲䈎䉌䇮SOA䈱MNAME䈮䈅䉎NS䉕೥㒰䈜䉎㽴 㽳䈪ᓧ䉌䉏䈢ฬ೨䉕ᔅⷐ䈮ᔕ䈛䈩⥄ಽ䈪ฬ೨⸃᳿䈚䇮
NOTIFY䉕ㅍ䉎• 䈧䉁䉍䇮ᮭᆭDNS䉰䊷䊋䊷ኾ↪䈮䈚䈢䈲䈝䈱BIND 9䈏䇮䉨䊞䉾䉲䊠DNS䉰䊷䊋䊷䈫䈚䈩േ૞䈚䈩䈇䉎䋣• 䉨䊞䉾䉲䊠DNS䉰䊷䊋䊷ᯏ⢻䈮䈱䉂ሽ࿷䈜䉎⣀ᒙᕈ䈱ᓇ㗀䉕ฃ䈔䉎น⢻ᕈ䈏䈅䉎
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴46੐ᓟ⾗ᢱ䈪ㅊട

BIND 9䈮䈍䈔䉎
NOTIFY䈱䉋䉍቟ో䈭ㆇ↪

• 䈍ᅑ䉄䋺䈖䈱ᯏ᭴䋨䈍䈞䈦䈎䈇䋩䈮㗬䉌䈭䈇– allowŞtransfer䈫ห᭽䇮named.conf䈪IP䉝䊄䊧䉴䉕᣿␜⊛䈮ᜰቯ䈜䉎– ᄖㇱ䈱DNS䉰䊷䊎䉴䉕೑↪䈜䉎႐ว䈭䈬䇮䉇䉃䉕ᓧ
䈭䈇ℂ↱䈪ᄖㇱฬ䉕૶↪䈜䉎႐ว䈮䉅૶䈋䉎– ⸳ቯ଀䈲ᰴ䊕䊷䉳䉕ෳᾖ䋨ᵈ䋺䈠䈱䉁䉁䉮䊏䊕ਇน䋩• ᰴༀ╷䋺䈜䈼䈩䈱ᮭᆭDNS䉰䊷䊋䊷䉕䈠䈱䉹䊷䊮䈱ฬ೨䋨㻛ౝㇱฬ䋩䈮䈜䉎– ฬ೨ᬌ⚝䈏ᔅⷐ䈭䈱䈲䇮ᮭᆭ䉕ᜬ䈢䈭䈇ᖱႎ䈱䉂– ᄖㇱฬ䉇ᆔછవ䈱ౝㇱฬ䈪䈅䈦䈢႐ว䇮ฬ೨ᬌ⚝䈏ᔅⷐ䈮䈭䉎
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੐ᓟ⾗ᢱ䈪ㅊട

BIND 9䈮䈍䈔䉎⸳ቯ଀䋨ᵈ䋺NOTIFY㑐ㅪ䈱䉂䈱ᛮ☴䈱䈢䉄䈠䈱䉁䉁䉮䊏䊕ਇน䋩• 䊒䊤䉟䊙䊥䉰䊷䊋䊷zone"example.jp” {....
//alsoŞnotify䈪᣿␜⊛䋨explicit䋩䈮ᜰቯ䈚䈢IP䉝䊄䊧䉴䈮䈱䉂NOTIFY䉕ㅍ䉎
notifyexplicit;//NOTIFY䉕ㅍ䉎䉶䉦䊮䉻䊥䉰䊷䊋䊷䈱IP䉝䊄䊧䉴䋨ᄌᦝ䈘䉏䈢䉌䈠䈱ㇺᐲᦝᣂ䋩alsoŞnotify{192.0.2.53;198.51.100.53;};};• 䉶䉦䊮䉻䊥䉰䊷䊋䊷zone"example.jp” {....
//NOTIFY䉕ㅍ䉌䈭䈇䋨ᜰቯ䈚䈭䈇䈫ή㚝䈭NOTIFY䉕ㅍ䉐䈉䈫䈜䉎䈱䈪ᵈᗧ䋩//notifyno;䈪䉅NOTIFY䈱ฃା䈮䈲ᓇ㗀䈚䈭䈇
notifyno;};
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3.䉫䊦䊷䈲䉫䊦䊷
䋨DNS䊂䊷䉺䈱䊤䊮䉨䊮䉫䋩

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㊀ⷐ䈭RFC䋺RFC 2181
• “Clarifications to the DNS Specification”– DNS઀᭽䈱᣿⏕ൻ

• 5.4.1. Ranking data– 䊂䊷䉺䈱಴⥄䋨source䋩䈏૗䈮↱᧪䈜䉎䈎䈮䉋䈦䈩䇮䈠䈱䊂䊷䉺䈱ା㗬ᐲ䋨trustworthiness䋩䈏᳿䉁䉎• ㎛䈫䈭䉎ⷐ⚛
– ᮭᆭ䉕ᜬ䈧ᔕ╵䈎䇮ᜬ䈢䈭䈇ᔕ╵䈎䋨AA䊎䉾䊃䈱᦭ή䋩– answer䇮authority䇮additional䈇䈝䉏䈱䉶䉪䉲䊢䊮䈮䈅䈦䈢䊂䊷䉺䈎䋨䉶䉪䉲䊢䊮䈱႐ᚲ䋩– ᮭᆭ䉕ᜬ䈧䊂䊷䉺䈎䇮ᜬ䈢䈭䈇䊂䊷䉺䈎䋨ᔕ╵ౝኈ䋩• CNAME䈱ಣℂ䈮㑐ଥ
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RFC 2181 5.4.1. Ranking data䋨ᛮ☴䋩㜞䈇䋨most䋩ᮭᆭ䉕ᜬ䈧ᔕ╵䈱answer section䈱ᮭᆭ䉕ᜬ䈧䊂䊷䉺ᮭᆭ䉕ᜬ䈧ᔕ╵䈱authority section䈱䊂䊷䉺ᮭᆭ䉕ᜬ䈢䈭䈇ᔕ╵䈱answer section䈱䊂䊷䉺䊶ᮭᆭ䉕ᜬ䈧ᔕ╵䈱answer section䈱ᮭᆭ䉕ᜬ䈢䈭䈇䊂䊷䉺ᮭᆭ䉕ᜬ䈧ᔕ╵䈱additional information䈱䊂䊷䉺䊶ᮭᆭ䉕ᜬ䈢䈭䈇ᔕ╵䈱authority section䈱䊂䊷䉺䊶ᮭᆭ䉕ᜬ䈢䈭䈇ᔕ╵䈱additional information䈱䊂䊷䉺䋨ᵈ䋺ේᢥ䈮additional section䈪䈲䈭䈒additional information䈫ᦠ䈎䉏䈩䈇䉎䋩
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴ૐ䈇䋨least䋩51䈖䈖䈪䈱䊘䉟䊮䊃• ᆔછᖱႎ䈲䇸৻⇟ૐ䈇䋨the least䋩ା㗬ᐲ䇹• ᆔછᖱႎ䋨NS䋩– ᮭᆭ䉕ᜬ䈢䈭䈇ᔕ╵䈱authority section• 䉫䊦䊷䋨A/AAAA䋩– ᮭᆭ䉕ᜬ䈢䈭䈇ᔕ╵䈱additional information

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䉫䊦䊷⥄り䈮ኻ䈜䉎໧䈇ว䉒䈞• ᆔછᖱႎ䈫䈚䈩╵䈋䉎ᔅⷐ䈅䉍• BIND 9䉇NSD䈪䈲ਅ⸥䈱䉋䈉䈮䋨ᱜ䈚䈒䋩╵䈋䉎– BIND 8䈮䈲䉫䊦䊷⥄り䈮ኻ䈜䉎໧䈇ว䉒䈞䈮ኻ䈚䇮䇸ᮭᆭ䉕ᜬ䈢䈭䈇ᔕ╵䈱answer section䇹䈫䈚䈩╵䈋䈩䈚䉁䈉䇮䈫䈇䈉໧㗴䈏䈅䈦䈢$dig+norec +noedns ns1.example.jpa@a.dns.jp…
;;flags:qr;QUERY:1,ANSWER:0, AUTHORITY:1,ADDITIONAL:1…
;;AUTHORITYSECTION:
example.jp.86400INNSns1.example.jp.
;;ADDITIONALSECTION:
ns1.example.jp.86400INA192.0.2.1
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴53䉫䊦䊷⥄り䈮ኻ䈜䉎໧䈇ว䉒䈞䋨⛯䈐䋩• 䉨䊞䉾䉲䊠DNS䉰䊷䊋䊷䈪䈲ᮭᆭDNS䉰䊷䊋䊷䈎䉌ฃ䈔ข䈦䈢ᆔછᖱႎ䋨NS䋩䉇䉫䊦䊷䉕䇮䈅䈒䉁䈪ᆔછᖱႎ䉇䉫䊦䊷䈫䈚䈩ᛒ䉒䈭䈔䉏䈳䈭䉌䈭䈇• 䈧䉁䉍䇮䉪䊤䉟䉝䊮䊃䈎䉌䈱໧䈇ว䉒䈞䈮ኻ䈚䇮䉫䊦䊷䉕answer section䈮౉䉏䈩╵䈋䈩䈲䈭䉌䈭䈇– ା㗬ᐲ䈱Ⴧട䋨increase䋩䉕᜗䈒– ㅢᏱ䈱ฬ೨ᬌ⚝䈮䉋䈦䈩䊤䊮䉨䊮䉫䈏䉋䉍㜞䈇䊂䊷䉺䉕౉ᚻ䈚䇮䈠䉏䉕╵䈋䉎ᔅⷐ䈅䉍
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴54଀䋺ᮭᆭDNS䉰䊷䊋䊷䈱ᒁ䈦⿧䈚ㅜਛ• ⷫ䈱NS/䉫䊦䊷䈫ሶ䈱NS/A䈏⇣䈭䈦䈩䈇䉎• ⷫ䈱NS/䉫䊦䊷䈲ฬ೨⸃᳿䈱ㅜਛ䈪৻ᤨ⊛䈮૶䉒䉏䉎䋨䈼䈐䋩– ሶ䈱NA/A䈱ᣇ䈏ⷫ䈱NS/䉫䊦䊷䉋䉍䉅ା㗬ᐲ䈏㜞䈇㪥㪪䈪ᆔછⷫ䈱ᮭᆭ㪛㪥㪪䉰䊷䊋䊷

ᒁ䈦⿧䈚ర
ᮭᆭ㪛㪥㪪
䉰䊷䊋䊷

ᒁ䈦⿧䈚వ
ᮭᆭ㪛㪥㪪
䉰䊷䊋䊷

ᣂ䈚䈇
䉹䊷䊮
䊂䊷䉺

ᣂ䈚䈇
䉹䊷䊮
䊂䊷䉺

㪥㪪䈪ឭ␜
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㪥㪪䈪ឭ␜
55

ౣឝ䋺ౝㇱฬ䈪䈅䈦䈢႐ว• ᆔછవ䈱NS䈏ౝㇱฬ䈪䈅䈦䈢႐ว䇮ᆔછవ䈱䈖䉏䈱ᔃ䉹䊷䊮䉁䈢䈲䈠䈱ౝ஥䈱䉹䊷䊮䈏䇮NS䈫䈚䈩ᜰቯ䈘䉏䈢ฬ೨䈮ኻ䈜䉎ᮭᆭ䉕ᔅ䈝ᜬ䈦䈩䈇䉎• 䈠䈱䈢䉄䇮ฃ䈔ข䈦䈢䉫䊦䊷䉕৻ᤨ⊛䈮ା↪䈚䈩䉹䊷䊮䉕䈢䈬䈦䈩䈇䈔䈳䇮䈇䈝䉏䈲䈠䈱ฬ೨䈮ኻ䈚ᮭᆭ䉕ᜬ䈧䋨ᧄᒰ䈮ା↪䈪䈐䉎䋩ᮭᆭ
DNS䉰䊷䊋䊷䈮ᔅ䈝಴ળ䈋䉎• 䈠䈱䈢䉄䇮ฬ೨⸃᳿䈮䈍䈇䈩ή᧦ઙ䈮䉫䊦䊷䉕ฃ䈔౉䉏䈩䉋䈇
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䊤䊮䉨䊮䉫䈱▤ℂ䈲䈐䉒䉄䈩㕙ୟ• ᵈᗧᷓ䈒ታⵝ䈚䈭䈇䈫䇮䊋䉫䉇⣀ᒙᕈ䈱䉅䈫䈮䈭䉍䉇䈜䈇• ଀䋺ⷫ䈱NS/䉫䊦䊷䈫ሶ䈱NS/A– ሶ䈱NS/A䈱ᣇ䈏ⷫ䈱NS/䉫䊦䊷䉋䉍䉅ା㗬ᐲ䈏਄• ఝవ⊛䈮ข䉍ᛒ䉒䉏䈭䈔䉏䈳䈭䉌䈭䈇– 䈚䈎䈚䇮ሶ䈱ା㗬ᐲ䈏㜞䈇䈱䈲ሶ䈏ሶ䈪䈅䉎㑆䈣䈔• ା㗬ᐲ䈏ૐ䈇ⷫ䈱䊂䊷䉺䈏䈭䈒䈭䉎䈖䈫䈪䇮ሶ䈱䊂䊷䉺䈏䈠䉅䈠䉅ା↪䈪䈐䈭䈒䈭䉎䋨ሶ䈏ሶ䈪䈭䈒䈭䉎䋩• ଀䋺䈇䉒䉉䉎ᶐㅘ໧㗴䉇ᐝ㔤䊄䊜䉟䊮ฬ⣀ᒙᕈ䈠䈚䈩䇮䈅䈱᦭ฬ䈭⣀ᒙᕈ䉅…
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4.䉦䊚䊮䉴䉨䊷ဳ᡹᠄ᚻᴺ

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䉦䊚䊮䉴䉨䊷ဳ᡹᠄ᚻᴺ• 䉻䊮䊶䉦䊚䊮䉴䉨䊷᳁䈏2008ᐕ䈮ᜰ៰䈚䈢᡹᠄ᚻᴺ• 䈚䈎䈚䇮䉦䊚䊮䉴䉨䊷᳁䈏␜䈚䈢䉥䊥䉳䊅䊦䈱ᣇᴺ䈪䈲䇮䉨䊞䉾䉲䊠䊘䉟䉵䊆䊮䉫䈲䈪䈐䈭䈇– ⺑᣿䈲⋭⇛䈚䉁䈜䋨㊀ⷐ䈭䈖䈫䈭䈱䈪ฦ⥄䈗⏕⹺䈒䈣䈘䈇䋩• ໧㗴ὐ䉕ୃᱜ䈚䈢᡹᠄ᣇᴺ䈏䈇䈒䈧䈎⊒⴫䈘䉏䈩䈇䉎– ਛ੩ᄢቇ䈱㋈ᧁᏱᒾవ↢䈏ታ㛎䋨*1䋩䈪૶䉒䉏䈢ᣇᴺ• એਅ䇸䊌䉺䊷䊮1䇹䇸䊌䉺䊷䊮2䇹䈫䈚䉁䈜– 䇸ታ〣DNS䇹䈮⸥ㅀ䈚䈢ᣇᴺ• એਅ䇸䊌䉺䊷䊮3䇹䈫䈚䉁䈜
䋨*1䋩BINDฦ䊋䊷䉳䊢䊮䈻䈱Ქ౉䉏ታ㛎 (Kaminsky Bug 䈱ᬌ⸽)<http://www.e-ontap.com/dns/bindmatrix.html>
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䉦䊚䊮䉴䉨䊷ဳ᡹᠄ᚻᴺ䋨䊌䉺䊷䊮1䋩
• ㋈ᧁవ↢䈱Web䊕䊷䉳䈱ᣇᴺ䉕䉅䈫䈮૞ᚑ;;flags:qr aa;QUERY:1,ANSWER:1,AUTHORITY:1,ADDITIONAL:1;;QUESTIONSECTION:;(random).example.jp.INA;;ANSWERSECTION:(random).example.jp.86400INA(ㆡᒰ䈭IP䉝䊄䊧䉴);;AUTHORITYSECTION:(random).example.jp.86400INNSwww.example.jp.
;;ADDITIONALSECTION:
www.example.jp.86400INA192.0.2.234(䉨䊞䉾䉲䊠䈘䈞䈢䈇னᖱႎ)
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴60䉦䊚䊮䉴䉨䊷ဳ᡹᠄ᚻᴺ䋨䊌䉺䊷䊮2䋩
• ㋈ᧁవ↢䈱Web䊕䊷䉳䈱ᣇᴺ䉕䉅䈫䈮૞ᚑ;;flags:qr aa;QUERY:1,ANSWER:1,AUTHORITY:1,ADDITIONAL:1;;QUESTIONSECTION:;(random).example.jp.INA;;ANSWERSECTION:(random).example.jp.86400INA(ㆡᒰ䈭IP䉝䊄䊧䉴);;AUTHORITYSECTION:
example.jp.86400INNSwww.example.jp.
;;ADDITIONALSECTION:
www.example.jp.86400INA192.0.2.234(䉨䊞䉾䉲䊠䈘䈞䈢䈇னᖱႎ)
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴61䉦䊚䊮䉴䉨䊷ဳ᡹᠄ᚻᴺ䋨䊌䉺䊷䊮3䋩• 䇸ታ〣DNS䇹p.298䉋䉍;;flags:qr aa;QUERY:1,ANSWER:1,AUTHORITY:1,ADDITIONAL:1;;QUESTIONSECTION:;(random).www.example.jp.INA;;ANSWERSECTION:(random).www.example.jp.86400INA(ㆡᒰ䈭IP䉝䊄䊧䉴);;AUTHORITYSECTION:
www.example.jp.86400INNSwww.example.jp.
;;ADDITIONALSECTION:
www.example.jp.86400INA192.0.2.234(䉨䊞䉾䉲䊠䈘䈞䈢䈇னᖱႎ)
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴62䈠䉏䈡䉏䈱㆑䈇• 䇸䊌䉺䊷䊮1䇹䈫䇸䊌䉺䊷䊮2䇹䈱㆑䈇– authority section䈱ౝኈ• 䊌䉺䊷䊮1: (random).example.jp䉹䊷䊮䈱NS• 䊌䉺䊷䊮2: example.jp䉹䊷䊮䈱NS• 䇸䊌䉺䊷䊮1䇹䇸䊌䉺䊷䊮2䇹䈫䇸䊌䉺䊷䊮3䇹䈱㆑䈇– ໧䈇ว䉒䈞/answer section䈱ౝኈ• 䊌䉺䊷䊮1/2: (random).example.jp䈱A• 䊌䉺䊷䊮3: (random).www.example.jp䈱A– authority section䈱ౝኈ• 䊌䉺䊷䊮1/2: 䋨਄⸥ෳᾖ䋩• 䊌䉺䊷䊮3: www.example.jp䉹䊷䊮䈱NS
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䊘䉟䊮䊃
• 䊤䊮䉨䊮䉫䈱ቯ⟵䈮䉋䉍䇮䇸䊌䉺䊷䊮1䇹䇸䊌䉺䊷䊮
2䇹䈱䇸ᮭᆭ䉕ᜬ䈧ᔕ╵䈱additional information䈱䊂䊷䉺䇹䈣䈔䈪䈲䇮䉨䊞䉾䉲䊠䊘䉟䉵䊆䊮䉫䈲ᚑ┙䈚䈭䈇䋨䈲䈝䋩– ㋈ᧁవ↢䈱ታ㛎䈱ㅢ䉍• 䈚䈎䈚䇮䈠䉏䈏ᚑ┙䈚䈩䈚䉁䈉BIND 9䈏ሽ࿷䈚䈢• 䈠䈚䈩䇮䈠䈱䊋䉫䈲ਅ⸥䈮䉋䉍ୃᱜ䈘䉏䈢
2786. [bug] Additional could be promoted to answer. [RT #20663]
䋨[bug] Additional䈏answer䈮਄᣹䈜䉎႐ว䈏䈅䉍ᓧ䈢䋩

Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴64䊘䉟䊮䊃䋨⛯䈐䋩• 䇸䊌䉺䊷䊮3䇹䈪䈲䇮– ᮭᆭ䉕ᜬ䈧ᔕ╵䈱authority section䈱䊂䊷䉺– ᮭᆭ䉕ᜬ䈧ᔕ╵䈱additional information䈱䊂䊷䉺䈱෺ᣇ䈮䇮www.example.jp䋨ᮡ⊛ฬ䋩䉕ᜰቯ䈚䈩䈇䉎• 䈖䉏䈮䉋䉍䇮᡹᠄䈏น⢻䈫䈭䉎– 䈢䈣䈚䇮ㅊട䈱Ꮏᄦ䈏ᔅⷐ䋨ᓟㅀ䋩• 䈢䈣䈚䇮䈖䈱ᤨὐ䈪ㅢᏱ䈱ฬ೨ᬌ⚝䈪ᓧ䈢䇮– ᮭᆭ䉕ᜬ䈧ᔕ╵䈱answer section䈱ᮭᆭ䉕ᜬ䈧䊂䊷䉺䉕ᣢ䈮䉨䊞䉾䉲䊠䈚䈩䈇䈢႐ว䇮᡹᠄䈲ᄬᢌ䈜䉎䋨䈲䈝䋩– 䈖䈱䈖䈫䈲㋈ᧁవ↢䈱ታ㛎䈪䉅⺑᣿䈘䉏䈩䈇䉎
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴65ㅊട䈱Ꮏᄦ
• 䈠䈚䈩䇮䉨䊞䉾䉲䊠䈘䈞䈢䈇னᖱႎ䈱䇮– ᮭᆭ䉕ᜬ䈧ᔕ╵䈱authority section䈱䊂䊷䉺– ᮭᆭ䉕ᜬ䈧ᔕ╵䈱additional information䈱䊂䊷䉺䉕䉅䈫䈮䇮– ᮭᆭ䉕ᜬ䈧ᔕ╵䈱answer section䈱ᮭᆭ䉕ᜬ䈧䊂䊷䉺䉕䉨䊞䉾䉲䊠䈘䈞䉎䈢䉄䈱Ꮏᄦ䈏ᔅⷐ䈮䈭䉎• 䇸ታ〣DNS䇹䈪䈲⣉ᵈ䈮⸥ㅀCopyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴66ㅊട䈱Ꮏᄦ䈮䉋䉎䊤䊮䉨䊮䉫䈱਄᣹• ㅊട䈱Ꮏᄦ䋺ன䈱ᆔછవ䋨䈖䈱଀䈪䈲192.0.2.234䋩䈪
ன䈱ᮭᆭDNS䉰䊷䊋䊷䉕┙䈤਄䈕䇮䉨䊞䉾䉲䊠䈘䈞䈢䈇னᖱႎ䈫ห䈛䊂䊷䉺䉕⸳ቯ䈚䈩䈍䈒• 䉨䊞䉾䉲䊠DNS䉰䊷䊋䊷䈏䇮᡹᠄⠪䈏⸳ቯ䈚䈢ன䈱ᮭ
ᆭDNS䉰䊷䊋䊷਄䈱னᖱႎ䉕ෳᾖ䈚䈢ᤨὐ䈪䇸ᮭᆭ䉕ᜬ䈧ᔕ╵䈱answer section䈱ᮭᆭ䉕ᜬ䈧䊂䊷䉺䇹䈫䈚䈩䉨䊞䉾䉲䊠䈘䉏䇮䉨䊞䉾䉲䊠䊘䉟䉵䊆䊮䉫䈏ᚑഞ䈜䉎䉶䉨䊠䊥䊁䉞਄䈱ℂ↱䈮䉋䉍䇮ౕ૕⊛䈭ᣇᴺ䈱⚫੺䈲⋭⇛䈚䉁䈜
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5.4.1. Ranking data䋨ౣឝ䋩䊌䉺䊷䊮3䈱䇸Ꮏᄦ䇹㜞䈇䋨most䋩ᮭᆭ䉕ᜬ䈧ᔕ╵䈱answer section䈱ᮭᆭ䉕ᜬ䈧䊂䊷䉺䊌䉺䊷䊮3ᮭᆭ䉕ᜬ䈧ᔕ╵䈱authority section䈱䊂䊷䉺ᮭᆭ䉕ᜬ䈢䈭䈇ᔕ╵䈱answer section䈱䊂䊷䉺䊶ᮭᆭ䉕ᜬ䈧ᔕ╵䈱answer section䈱ᮭᆭ䉕ᜬ䈢䈭䈇䊂䊷䉺䊌䉺䊷䊮1/2ᮭᆭ䉕ᜬ䈧ᔕ╵䈱additional information䈱䊂䊷䉺䊶ᮭᆭ䉕ᜬ䈢䈭䈇ᔕ╵䈱authority section䈱䊂䊷䉺䊶ᮭᆭ䉕ᜬ䈢䈭䈇ᔕ╵䈱additional information䈱䊂䊷䉺ૐ䈇䋨least䋩
Copyright © 2013 ᩣᑼળ␠ᣣᧄ䊧䉳䉴䊃䊥䉰䊷䊎䉴68੐ᓟ⾗ᢱ䈪ᦝᣂ䋨ᦨᓟ䈱㗄⋡䋩䉁䈫䉄䋺䉦䊚䊮䉴䉨䊷ဳ᡹᠄ᚻᴺ
• ᚻᴺ䈱ᛛⴚ⊛ℂ⸃䈫䈠䈱ᬌ⸽䈏㕖Ᏹ䈮㕙ୟ– 䈖䈱䊌䊷䊃䈱⹤䈲㔍䈚䈎䈦䈢䈫ᕁ䈇䉁䈜䋨䈗䉄䉖䈭䈘䈇䋩• RFC 2181䉕⺒䉂ㄟ䉁䈭䈔䉏䈳䉒䈎䉌䈭䈇– ታ䈱䈫䈖䉐䇮⺒䉂ㄟ䉖䈪䉅䉋䈒䉒䈎䉌䈭䈇– ታ䈲⑳䉅䉒䈎䈦䈩䈇䈭䈇䈱䈎䉅• 䈎䈧䇮ታⵝ਄䈱䊋䉫䉅⛊䉖䈪䈒䉎– ታⵝ䈮䈍䈔䉎䊤䊮䉨䊮䉫䈱▤ℂ䈲䈐䉒䉄䈩㕙ୟ• 䈠䈚䈩䇮RFC 2181䈱䊤䊮䉨䊮䉫䈠䈱䉅䈱䉇⃻ሽ䈜䉎ታⵝ䈏ቢో䈭䉅䈱䈎䈬䈉䈎䈲⺕䈮䉅䉒䈎䉌䈭䈇
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Q&A

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