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2009/12/4-1

Google Public DNS�����\����Ă��܂����B �uOfficial Google Blog: Introducing Google Public DNS�v

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Performance Benefits
http://code.google.com/intl/ja/speed/public-dns/docs/performance.html

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Google Public DNS is hosted in data centers worldwide, and uses anycast routing to send users to the geographically closest data center.

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That is, if a content provider hosts mirrored sites around the world, that provider's nameservers will return the IP address in closest proximity to the DNS resolver.

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Security Benefits
http://code.google.com/intl/ja/speed/public-dns/docs/security.html

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  • Strictly prioritize prefetch traffic above user traffic, thereby rate-limiting traffic to nameservers.
  • Partition caches according to the type of traffic, preventing attackers from writing garbage entries to the prefetch cache; and preventing the prefetch system from reading poisoned delegations from the user cache.
  • Keep enough popular names in the cache to satisfy most user queries, continuing to serve users even when under attack.

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Google Public DNS, never allows more than a single outstanding request for the same query name, query type, and destination IP address.

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Google Public DNS : Your Privacy : http://code.google.com/intl/ja/speed/public-dns/privacy.html

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  • Request domain name, e.g. www.google.com
  • Request type, e.g. A (which stands for IPv4 record), AAAA (IPv6 record), NX, TXT, etc.
  • Transport protocol on which the request arrived, i.e. TCP or UDP
  • Client's AS (autonomous system or ISP), e.g. AS15169
  • User's geolocation information: i.e. geocode, region ID, city ID, and metro code
  • Response code sent, e.g. SUCCESS, SERVFAIL, NXDOMAIN, etc.
  • Whether the request hit our frontend cache
  • Whether the request hit a cache elsewhere in the system (but not in the frontend)
  • Absolute arrival time in seconds
  • Total time taken to process the request end-to-end, in seconds
  • Name of the Google machine that processed this request, e.g. machine101
  • Google target IP to which this request was addressed, e.g. one of our anycast IP addresses (no relation to the user's IP)

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route:      8.8.8.0/24
descr:      Google
origin:     AS15169
notify:     [email protected]
mnt-by:     MAINT-AS15169
changed:    [email protected] 20091103
source:     RADB

route:         8.0.0.0/9
descr:         Proxy-registered route object
origin:        AS3356
remarks:       auto-generated route object
remarks:       this next line gives the robot something to recognize
remarks:       L'enfer, c'est les autres
remarks:       
remarks:       This route object is for a Level 3 customer route
remarks:       which is being exported under this origin AS.
remarks:       
remarks:       This route object was created because no existing
remarks:       route object with the same origin was found, and
remarks:       since some Level 3 peers filter based on these objects
remarks:       this route may be rejected if this object is not created.
remarks:       
remarks:       Please contact [email protected] if you have any
remarks:       questions regarding this object.
mnt-by:        LEVEL3-MNT
changed:       [email protected] 20060203
source:        LEVEL3


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route:      8.8.4.0/24
descr:      Google
origin:     AS15169
notify:     [email protected]
mnt-by:     MAINT-AS15169
changed:    [email protected] 20091109
source:     RADB

route:         8.0.0.0/9
descr:         Proxy-registered route object
origin:        AS3356
remarks:       auto-generated route object
remarks:       this next line gives the robot something to recognize
remarks:       L'enfer, c'est les autres
remarks:       
remarks:       This route object is for a Level 3 customer route
remarks:       which is being exported under this origin AS.
remarks:       
remarks:       This route object was created because no existing
remarks:       route object with the same origin was found, and
remarks:       since some Level 3 peers filter based on these objects
remarks:       this route may be rejected if this object is not created.
remarks:       
remarks:       Please contact [email protected] if you have any
remarks:       questions regarding this object.
mnt-by:        LEVEL3-MNT
changed:       [email protected] 20060203
source:        LEVEL3


traceroute

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Abovenet(�A�����J)

traceroute to 8.8.8.8 (8.8.8.8), 30 hops max, 40 byte packets
 1  so-2-1-0.mpr2.ams5.nl.above.net (64.125.31.254)  0.706 ms  0.587 ms  0.564 ms
 2  so-2-0-0.mpr1.lhr2.uk.above.net (64.125.27.177)  6.351 ms  7.230 ms  7.294 ms
 3  xe-1-1-0.mpr1.lhr1.uk.above.net (64.125.27.150)  5.981 ms  58.400 ms  13.661 ms
 4  72.14.217.93 (72.14.217.93)  108.082 ms  6.054 ms  6.133 ms
 5  209.85.252.76 (209.85.252.76)  6.284 ms  6.355 ms  6.277 ms
 6  72.14.232.134 (72.14.232.134)  13.153 ms 66.249.95.170 (66.249.95.170)  14.117 ms 72.14.232.134 (72.14.232.134)  13.079 ms
 7  209.85.251.231 (209.85.251.231)  13.231 ms  13.222 ms 72.14.236.191 (72.14.236.191)  36.229 ms
 8  209.85.243.73 (209.85.243.73)  13.376 ms 209.85.243.81 (209.85.243.81)  18.063 ms 209.85.243.73 (209.85.243.73)  28.517 ms
 9  google-public-dns-a.google.com (8.8.8.8)  12.375 ms  14.095 ms  16.414 ms


DIX-IE(���{)

traceroute to 8.8.8.8 (8.8.8.8), 30 hops max, 38 byte packets
 1  jp-gw.apnic.net (202.12.28.190)  0.306 ms  0.265 ms  0.324 ms
 2  as15169.dix-ie.jp (202.249.2.189)  0.500 ms  0.527 ms  1.579 ms
 3  209.85.241.64 (209.85.241.64)  0.743 ms 209.85.241.68 (209.85.241.68)  1.087 ms  0.958 ms
 4  209.85.250.86 (209.85.250.86)  33.468 ms 209.85.250.90 (209.85.250.90)  31.208 ms 209.85.250.86 (209.85.250.86)  31.661 ms
 5  209.85.250.101 (209.85.250.101)  32.213 ms 209.85.243.23 (209.85.243.23)  32.076 ms 209.85.243.21 (209.85.243.21)  32.058 ms
 6  209.85.241.154 (209.85.241.154)  42.708 ms 209.85.241.158 (209.85.241.158)  35.213 ms  37.185 ms
 7  google-public-dns-a.google.com (8.8.8.8)  32.223 ms  32.291 ms  32.071 ms


PTTmetro(�u���W��)

traceroute to 8.8.8.8 (8.8.8.8), 30 hops max, 38 byte packets
 1  ar03.registro.br (200.160.7.129)  1.892 ms  2.373 ms  1.056 ms
 2  ar01.agr.registro.br (200.160.0.145)  0.740 ms  1.139 ms  1.195 ms
 3  ge-0-1-0.0.gw03.registro.br (200.160.0.243)  0.366 ms  0.392 ms  0.325 ms
 4  as15169.sp.ptt.br (200.219.130.55)  0.741 ms  0.646 ms  0.706 ms
 5  209.85.249.232 (209.85.249.232)  0.870 ms 209.85.250.246 (209.85.250.246)  1.569 ms  1.127 ms
 6  72.14.233.89 (72.14.233.89)  1.494 ms 72.14.233.91 (72.14.233.91)  1.608 ms 72.14.233.95 (72.14.233.95)  1.583 ms
 7  64.233.175.58 (64.233.175.58)  1.466 ms 64.233.175.62 (64.233.175.62)  7.037 ms 64.233.175.58 (64.233.175.58)  3.504 ms
 8  google-public-dns-a.google.com (8.8.8.8)  1.482 ms  1.464 ms  1.454 ms


MSK-IX(Moscow IX,���W�A)

traceroute to 8.8.8.8 (8.8.8.8), 30 hops max, 38 byte packets
 1  194.190.133.33 (194.190.133.33)  0.472 ms  0.442 ms  0.507 ms
 2  msk-ix-gw2.google.com (193.232.246.232)  1.071 ms  1.145 ms  1.161 ms
 3  72.14.239.254 (72.14.239.254)  37.924 ms  38.172 ms  38.013 ms
 4  72.14.236.251 (72.14.236.251)  52.963 ms  103.694 ms  53.006 ms
 5  72.14.232.203 (72.14.232.203)  52.928 ms  52.792 ms 72.14.232.201 (72.14.232.201)  52.445 ms
 6  72.14.233.210 (72.14.233.210)  52.958 ms 72.14.233.206 (72.14.233.206)  60.755 ms  56.971 ms
 7  google-public-dns-a.google.com (8.8.8.8)  53.166 ms  52.867 ms  53.048 ms


Netnod-IX(�X�E�F�[�f��)

traceroute to 8.8.8.8 (8.8.8.8), 30 hops max, 38 byte packets
 1  rrc-gw.sth.netnod.se (194.146.105.181)  0.285 ms  0.239 ms  0.173 ms
 2  10ge-2-1.outer-c-gw.sth.netnod.se (77.72.228.13)  0.237 ms  0.204 ms  0.265 ms
 3  htg0-core-1.gigabiteth0-0-0.swip.net (194.68.123.21)  0.363 ms  0.290 ms  0.349 ms
 4  kst-core-1.tengigabiteth8-0-0.swip.net (130.244.218.154)  0.491 ms  0.518 ms  0.577 ms
 5  avk-core-2.tengigabiteth4-1.swip.net (130.244.39.10)  0.614 ms  0.602 ms  0.661 ms
 6  some.stockholm.router.google.com (130.244.200.46)  1.864 ms  0.687 ms  0.622 ms
 7  209.85.252.186 (209.85.252.186)  0.740 ms  0.783 ms  0.778 ms
 8  209.85.254.153 (209.85.254.153)  28.716 ms  28.722 ms 209.85.248.132 (209.85.248.132)  29.021 ms
 9  64.233.174.55 (64.233.174.55)  29.588 ms 64.233.174.53 (64.233.174.53)  28.499 ms 64.233.174.29 (64.233.174.29) 28.400 ms
10  209.85.255.249 (209.85.255.249)  29.468 ms 209.85.255.245 (209.85.255.245)  39.127 ms 209.85.250.5 (209.85.250.5) 34.776 ms
11  google-public-dns-a.google.com (8.8.8.8)  29.468 ms  29.509 ms  29.310 ms


APOL (Asia Pasific OnLine, ��p)

1 211-76-96-253.ebix.net.tw (211.76.96.253) 0.363 ms 0.331 ms
2 72.14.196.13 (72.14.196.13) 0.576 ms 0.545 ms
3 209.85.243.30 (209.85.243.30) 1.765 ms 209.85.243.26 (209.85.243.26) 0.572 ms
4 209.85.250.101 (209.85.250.101) 1.632 ms 209.85.250.103 (209.85.250.103) 1.714 ms
5 209.85.241.162 (209.85.241.162) 2.964 ms 209.85.241.158 (209.85.241.158) 3.591 ms 
6 google-public-dns-a.google.com (8.8.8.8) 1.972 ms 2.139 ms 

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