2015 User-AgentDNS 2016 2 1 5114F058-7
1 3 1.1..................................... 3 1.2..................................... 4 1.3.................................... 4 2 DNS 5 2.1 DNS...................................... 5 2.1.1 DNS................................. 5 2.1.2 DNS....................... 5 2.2 DNS................................... 6 2.2.1 DNS........................... 6 2.2.2 DNS................. 6 3 11 3.1....................................... 11 3.1.1.............................. 11 3.1.2 TTL................................. 14 3.2................................... 15 4 18 4.1................................ 18 4.2 User-Agent......................... 18 4.3.................................... 20 4.4..................................... 33 4.4.1.......................... 33 4.4.2......................... 34 4.4.3............... 34 1
4.5 IP.................... 35 5 38 5.1........................................ 38 5.2..................................... 38 5.2.1...................... 38 5.2.2.................... 38 40 41 2
2.1 Windows 2.................. 7 2.2.......................... 8 2.3 1 www.apple.com, HTTP........... 9 2.4 www.goto.info.waseda.ac.jp DNS........... 9 2.5 1 www.goto.info.waseda.ac.jp, HTTP..... 10 3.1 DNS TTL........................ 12 3.2...................... 13 3.3 TTL................................ 15 3.4............................. 16 4.1 www.yahoo.co.jp, User-Agent................. 21 4.2 www.yahoo.co.jp, Windows....................... 21 4.3 www.yahoo.co.jp, Mac OS........................ 22 4.4 www.yahoo.co.jp, ios.......................... 22 4.5 www.yahoo.co.jp, Android........................ 23 4.6 www.yahoo.co.jp, Internet Explorer................... 23 4.7 www.yahoo.co.jp, Google Chrome.................... 24 4.8 www.yahoo.co.jp, Firefox........................ 24 4.9 www.facebook.com, User-Agent................ 25 4.10 www.facebook.com, Windows...................... 25 4.11 www.facebook.com, Mac OS....................... 26 4.12 www.facebook.com, Android....................... 26 4.13 www.facebook.com, ios......................... 27 4.14 www.facebook.com, Internet Explorer................. 27 4.15 www.facebook.com, Google Chrome.................. 28 4.16 www.facebook.com, Firefox....................... 28 4.17 platform.twitter.com, User-Agent............... 29 3
4.18 platform.twitter.com, Windows..................... 29 4.19 platform.twitter.com, Mac OS...................... 30 4.20 platform.twitter.com, ios........................ 30 4.21 platform.twitter.com, Internet Explorer................. 31 4.22 platform.twitter.com, Google Chrome.................. 31 4.23 platform.twitter.com, Firefox...................... 32 4.24 platform.twitter.com, Safari....................... 32 4.25 www.google.co.jp, User-Agent................. 35 4.26 100.................. 36 4.27.............................. 37 4
1 1.1 DNS (Domain Name System) IP DNS DNS [1] DNS 1 BIND 9 [2] DNS TLD (Top Level Domain) DNS DNS 2.2.2 Web DNS DNS DNS [3] DNS HTTPS Google 2013 9 [4] Yahoo 2015 8 [5] HTTPS CDN (Contents Delivery Network) DNS HTTPS 5
1 1.2 3.1.1 TTL TTL 2 OS (Operating System) Web OS Web DNS User-Agent 1.3 1 2 DNS DNS 3 4 5 6
2 DNS 2.1 DNS DNS 2.1.1 DNS DNS IP ( ) [6] IP IP 2.1.2 DNS DNS DNS www.exmaple.com www.exmaple.com DNS DNS DNS www.exmaple.com IP com IP DNS DNS com www.exmaple.com example.com IP DNS example.com www.exmaple.com www.exmaple.com IP DNS www.exmaple.com IP 7
2 DNS DNS DNS DNS DNS 2.2.1 2.2 DNS DNS DNS 2.2.1 DNS DNS IP TTL IP DNS TTL 0 DNS DNS DNS DNS Web OS 2.2.2 DNS DNS 2.2.1 4 OS Web 4.2 2015 8 Web DNS DNS 1 2.1 Windows 7 [7] DNS 2 Web HTTP://www.goto.info.waseda.ac.jp/ Internet Explorer [8] ( 11.0.9600.17959) Google 8
2 DNS Chrome [9] ( 44.0.2403.155 m 64-bit) 2.1: Windows 2 Internet Explorer Google Chrome Windows Web 2 OS DNS Internet Explorer Fire Fox [10] ( 40.0.2) OS DNS 1 2 OS DNS 2 Web Twitter [11] Web Web DNS 2.2 Google Chrome HTTP://www.apple.com/ 10 10 pcap Wireshark [12] HTTP://www.apple.com/ DNS HTTP://www.apple.com/ HTTP DNS DNS 9
2 DNS DNS 2.2: DNS HTTP://www.apple.com/ TTL 30 10 TTL 0 2.3 pcap HTTP 1 10
2 DNS 2.3: 1 www.apple.com, HTTP HTTP DNS 1 HTTP TCP 10 DNS TCP DNS HTTP://www.goto.info.waseda.ac.jp/ TTL 60 ipconfig /flushdns Windows DNS www.goto. info.waseda.ac.jp DNS 2.4 2.4: www.goto.info.waseda.ac.jp DNS 10 DNS 10 OS DNS 11
2 DNS www.goto.info.waseda.ac.jp DNS pcap HTTP 1 index.html 2.5 2.5: 1 www.goto.info.waseda.ac.jp, HTTP 2.3 1 1 TCP HTTP://www.apple.com/ TCP 10 DNS HTTP DNS 2.2.1 DNS 12
3 3.1 3.1.1 DNS TTL DNS TTL 3.1 13
3 3.1: DNS TTL 3 DNS 1 1 IP TTL 40 10 2 DNS TTL 10 TTL 30 1 10 TTL 30 3 3 TTL 20 DNS 1 2 TTL 20 TTL DNS q(t) = Nre r mod(t,ttl) + ϵ (3.1) q(t) : N : TTL 14
3 r : [1/s] t : [s] TTL : TTL ϵ : TTL mod(t, TTL) : t TTL TTL TTL N ϵ TTL DNS TTL TTL 3.2: N = 4000 15
3 r = 0.1 ϵ = 100 TTL = 60 DNS q(t) TTL 0 TTL ϵ 0 N, r, ϵ 3 3.1.2 TTL DNS DNS DNS DNS TTL DNS TTL TTL TTL T c = T 2 (T 1 + TTL) (3.2) T 1 : n DNS T 2 : n+1 DNS TTL : n DNS TTL 3.3 16
3 3.3: TTL www.example.com DNS 12:00:00 TTL 30 DNS 30 12:00:30 www.example.com DNS 12:01:10 T 1 = (12 : 00 : 00), T 2 = (12 : 01 : 00), TTL = 30 TTL T c = 40(s) TTL DNS DNS DNS DNS DNS () 3.1 1 3.2 3.1 1 User-Agent 17
3 3.4: DNS HTTP pcap DNS DNS HTTP 3 1 3 1. 2. 3. HTTP 18
3 1 DNS 2 3 1 2 HTTP DNS User-Agent HTTP User-Agent HTTPS IP User-Agent 2 3 HTTP 3 3 2 1 3 2 3.1.2 TTL DNS TTL TTL () 1 User-Agent 19
4 4.1 DNS HTTP 2013 8 4 TTL HTTP HTTPS 4 1 ( ) 1 2 4 Web 4 Web 2 Web 4 1 96 4.2 User-Agent HTTP 3 20
4 www.yahoo.co.jp www.facebook.com platform.twitter.com www.yahoo.co.jp Yahoo! JAPAN [13] Yahoo! JAPAN Google [14] 2 9 [15] www.facebook.com Facebook [16] [17] 2015 9 1 10 platform.twitter.com Twitter User-Agent OS Web OS 4 OS Windows Mac OS Android ios Windows (Microsoft Windows) Microsoft OS [7] Mac OS Apple OS [18] NetMarketShare [19] 2013 Windows 9 LinuxOS Android Google OS [20] ios Apple OS Apple iphone ipad [21] Web 4 Internet Explorer Google Chrome Firefox Safari 21
4 Internet Explorer Microsoft Windows Web 2013 Microsoft Web Edge [22] Google Chrome Google Web Firefox (Mozilla Firefox) Mozilla Web Safari Apple Web Apple OS Mac OS ios [23] OS Web OS Web 4.3 3 8 24 All User-Agent OS Web OS Web OS Web 22
4 4.1: www.yahoo.co.jp, User-Agent 4.2: www.yahoo.co.jp, Windows 23
4 4.3: www.yahoo.co.jp, Mac OS 4.4: www.yahoo.co.jp, ios 24
4 4.5: www.yahoo.co.jp, Android 4.6: www.yahoo.co.jp, Internet Explorer 25
4 4.7: www.yahoo.co.jp, Google Chrome 4.8: www.yahoo.co.jp, Firefox 26
4 4.9: www.facebook.com, User-Agent 4.10: www.facebook.com, Windows 27
4 4.11: www.facebook.com, Mac OS 4.12: www.facebook.com, Android 28
4 4.13: www.facebook.com, ios 4.14: www.facebook.com, Internet Explorer 29
4 4.15: www.facebook.com, Google Chrome 4.16: www.facebook.com, Firefox 30
4 4.17: platform.twitter.com, User-Agent 4.18: platform.twitter.com, Windows 31
4 4.19: platform.twitter.com, Mac OS 4.20: platform.twitter.com, ios 32
4 4.21: platform.twitter.com, Internet Explorer 4.22: platform.twitter.com, Google Chrome 33
4 4.23: platform.twitter.com, Firefox 4.24: platform.twitter.com, Safari 34
4 4.4 () DNS TTL TTL 2 DNS 0 2 3 TTL www.yahoo.co.jp www.facebook.com 60 platform.twitter.com 3600 TTL 3.3 TTL DNS 0 3.2 1 TTL 0 3 4.4.1 4.13 www.facebook.com ios 0 DNS ios 4.20 DNS ios 0 DNS 3.1 Nre r mod(t,ttl) TTL ϵ ios Facebook DNS TTL Facebook DNS 3.1 Nre r mod(t,ttl) ϵ 35
4 4.4.2 4.7 4.15 www.yahoo.co.jp www.facebook.com Google Chrome 4.12 www.facebook.com Android DNS 4.15 120 DNS TTL DNS Google Chrome Android Google Web OS Google Chrome DNS OS Google Chrome DNS TTL 60 [24] 2.2.2 Google Chrome TTL 30 TTL TTL DNS 4.4.3 www.yahoo.co.jp www.facebook.com 3000 3500 www.google.co.jp User-Agent 36
4 4.25: www.google.co.jp, User-Agent www.facebook.com Android 4.12 platform.twitter.com 4.17 600 TTL 3600 3000 DNS 0 3000 DNS 3000 4.5 IP 4.3 DNS 0 DNS 0 37
4 IP 4.3 www.facebook.com 24 A B 2 A 0 120 B 1000 900 4.26 A B 100 1600 4.26: 100 B A A 2.78% 100 4.27 IP 38
4 4.27: 4.26 A B 4.3 DNS 39
5 5.1 DNS User-Agent User-Agent 5.2 5.2.1 4.3 OS Web OS Web 4.2 LinuxOS User-Agent User-Agent 5.2.2 4.1 DNS HTTP 2013 8 4 Windows Internet Explorer All 2 User-Agent 40
5 Windows Internet Explorer Web OS OS Web All User-Agent All User-Agent 41
NTT 42
[1],,, DNS, B Vol.J98-B No.6, pp.497-508, June, 2013. [2] BIND Internet System Consortium https://www.isc.org/downloads/bind/ [3] A. Shimoda, K. Ishibashi, K. Sato, M. Tsujino, T. Inoue, M. Shimura, T. Takebe, K. Takahashi, T. Mori, and S. Goto, Inferring Popularity of Domain Names with DNS Traffic: Exploiting Cache Timeout Heuristics IEEE Global Communications Conference, December 2015, San Diego CA, US. [4] Post-PRISM, Google Confirms Quietly Moving To Make All Searches Secure, Except For Ad Clicks http://searchengineland.com/post-prism-google-secure-searches-172487 [5] Yahoo! SSL http://docs.yahoo.co.jp/info/notice/150812.html [6] Paul Albitz, Cricket Liu,,,, DNS&BIND ( 4 ),, Feb. 2002. [7] Windows Windows 10 - http://www.microsoft.com/ja-jp/windows [8] Internet Explorer - Microsoft Windows http://windows.microsoft.com/ja-jp/internet-explorer/download-ie [9] Chrome - Google https://www.google.co.jp/chrome/browser/desktop/index.html [10] Firefox browser - Mozilla https://www.mozilla.org/en-us/firefox/new/ 43
[11] Twitter https://twitter.com/ [12] Wireshark https://www.wireshark.org/ [13] Yahoo! JAPAN http://www.yahoo.co.jp/ [14] Google https://www.google.co.jp/ [15] ( ) http://find.accessup.org/kensaku/access_history.html [16] Facebook https://www.facebook.com/ [17] Facebook http://ja.newsroom.fb.com/company-info/ [18] OS X - OS X? - Apple http://www.apple.com/jp/osx/ [19] NetMarketShare https://www.netmarketshare.com/ [20] Android Google OS https://www.android.com/ [21] ios 9 - Apple http://www.apple.com/ios/ [22] Microsoft Edge - https://www.microsoft.com/ja-jp/windows/microsoft-edge [23] OS X - Safari - Apple http://www.apple.com/safari/ [24] 1 min TTL in DNS cache https://code.google.com/p/chromium/issues/detail?id=164026 44
[25] Chrome Networking: DNS Prefetch & TCP Preconnect https://www.igvita.com/2012/06/04/chrome-networking-dns-prefetch-and-tcppreconnect/ 45