にょろぷにらん

まず，これらのIPは物理的にどこにおかれているのか？が気になる．

そこで，BGP IPv4/IPv6 Looking Glass Servers からCable & WirelessのLooking Glassを指定して，世界各地からtracerouteを行ってみた．

東京から

1 so-3-0-0-ccr2.hkg.cw.net (195.2.18.82) 44.068 ms 44.072 ms 44.236 ms
2 google3-10G.hkix.net (202.40.161.10) 68.557 ms 46.426 ms 94.975 ms
3 209.85.241.56 (209.85.241.56) [AS 15169] 46.362 ms 46.317 ms 46.283 ms
4 209.85.250.120 (209.85.250.120) [AS 15169] 67.646 ms 69.492 ms 67.649 ms
5 209.85.243.23 (209.85.243.23) [AS 15169] 67.601 ms 209.85.250.103 (209.85.250.103) [AS 15169] 65.932 ms 209.85.243.21 (209.85.243.21) [AS 15169] 67.768 ms
6 209.85.241.158 (209.85.241.158) [AS 15169] 76.195 ms 209.85.241.162 (209.85.241.162) [AS 15169] 75.170 ms 209.85.241.154 (209.85.241.154) [AS 15169] 74.439 ms
7 google-public-dns-a.google.com (8.8.8.8) [AS 15169] 68.247 ms 69.396 ms 67.892 ms

Singaporeから．

1 ae1-ccr2.sng.cw.net (195.2.18.34) 0.719 ms 0.701 ms 0.593 ms
2 p15169.sgw.equinix.com (202.79.197.30) 0.570 ms 0.639 ms 0.555 ms
3 209.85.243.156 (209.85.243.156) [AS 15169] 0.964 ms 1.057 ms 0.985 ms
4 209.85.241.221 (209.85.241.221) [AS 15169] 48.424 ms 48.612 ms 48.425 ms
5 209.85.250.103 (209.85.250.103) [AS 15169] 49.571 ms 49.552 ms 209.85.250.101 (209.85.250.101) [AS 15169] 51.377 ms
6 209.85.241.166 (209.85.241.166) [AS 15169] 49.415 ms 209.85.241.162 (209.85.241.162) [AS 15169] 50.490 ms 56.785 ms
7 google-public-dns-a.google.com (8.8.8.8) [AS 15169] 49.684 ms 50.216 ms 55.273 ms

Washington DCから

1 so-7-0-0-dcr1.nyk.cw.net (195.2.3.2) 29.182 ms 5.808 ms 5.383 ms
2 xe-7-2-0.xcr1.nyk.cw.net (195.2.25.142) 5.435 ms xe-0-0-0.xcr1.nyk.cw.net (195.2.25.9) 5.306 ms 5.393 ms
3 core1-0-2-0.lga.net.google.com (198.32.160.130) 5.575 ms 5.418 ms 5.325 ms
4 72.14.238.232 (72.14.238.232) [AS 15169] 5.607 ms 5.594 ms 209.85.255.68 (209.85.255.68) [AS 15169] 5.500 ms
5 72.14.239.93 (72.14.239.93) [AS 15169] 12.824 ms 209.85.249.11 (209.85.249.11) [AS 15169] 12.758 ms 209.85.248.216 (209.85.248.216) [AS 15169] 11.961 ms
6 64.233.175.109 (64.233.175.109) [AS 15169] 13.221 ms 72.14.236.200 (72.14.236.200) [AS 15169] 12.680 ms 64.233.175.111 (64.233.175.111) [AS 15169] 12.815 ms
7 72.14.232.21 (72.14.232.21) [AS 15169] 12.789 ms 216.239.49.145 (216.239.49.145) [AS 15169] 19.793 ms 72.14.232.21 (72.14.232.21) [AS 15169] 12.720 ms
8 google-public-dns-a.google.com (8.8.8.8) [AS 15169] 13.405 ms 12.888 ms 12.987 ms

Los Angelesから

1 core1-0-1-0.lax.net.google.com (198.32.146.46) 74.811 ms 73.153 ms 73.429 ms
2 216.239.43.14 (216.239.43.14) [AS 15169] 73.377 ms 73.327 ms 73.366 ms
3 72.14.232.85 (72.14.232.85) [AS 15169] 90.133 ms 85.548 ms 85.653 ms
MPLS Label=723795 CoS=4 TTL=1 S=1
4 216.239.48.34 (216.239.48.34) [AS 15169] 85.977 ms 86.047 ms 209.85.250.144 (209.85.250.144) [AS 15169] 90.268 ms
5 64.233.174.131 (64.233.174.131) [AS 15169] 86.021 ms 64.233.174.123 (64.233.174.123) [AS 15169] 86.175 ms 64.233.174.121 (64.233.174.121) [AS 15169] 86.160 ms
6 216.239.49.246 (216.239.49.246) [AS 15169] 88.546 ms 209.85.254.150 (209.85.254.150) [AS 15169] 91.380 ms 209.85.254.146 (209.85.254.146) [AS 15169] 123.222 ms
7 google-public-dns-a.google.com (8.8.8.8) [AS 15169] 86.527 ms 86.213 ms 86.272 ms

Parisから

1 xe-4-3-0.xcr1.par.cw.net (195.2.9.233) 0.798 ms 0.615 ms xe-7-2-0.xcr1.par.cw.net (195.2.25.145) 0.688 ms
2 xe-0-0-0.xcr1.fra.cw.net (195.2.9.213) 11.204 ms xe-0-1-0.xcr1.fra.cw.net (195.2.9.225) 9.173 ms xe-0-2-0.xcr1.fra.cw.net (195.2.9.229) 9.253 ms
3 72.14.198.109 (72.14.198.109) 61.945 ms 38.412 ms 9.394 ms
4 209.85.248.12 (209.85.248.12) [AS 15169] 16.681 ms 9.508 ms 209.85.254.108 (209.85.254.108) [AS 15169] 9.728 ms
5 72.14.232.167 (72.14.232.167) [AS 15169] 10.297 ms 72.14.232.203 (72.14.232.203) [AS 15169] 9.903 ms 72.14.232.201 (72.14.232.201) [AS 15169] 9.835 ms
6 72.14.233.210 (72.14.233.210) [AS 15169] 19.538 ms 72.14.233.206 (72.14.233.206) [AS 15169] 21.669 ms 54.676 ms
7 google-public-dns-a.google.com (8.8.8.8) [AS 15169] 10.483 ms 10.575 ms 10.204 ms

各地からの応答が100ms以下であることとそこまでの経路が異なることから，世界各地に分散配置していると考えられる．

また，IANAのIPv4 番号割り当てによれば，008/8はLevel 3 Communications, Inc.に割り当てられているが，tracerouteの結果を見るとサーバはGoogle内部にあるようだ．

そこで，CIDR-report でAS 15169を見てみる．

Announced Prefixesを見ると，上の方に

Rank AS AS Name Current Wthdw Aggte Annce Redctn %
165 AS15169 GOOGLE - Google Inc. 137 118 1 20 117 85.40%


Prefix AS Path Aggregation Suggestion
4.3.2.0/24 4777 15169
8.8.4.0/24 4777 15169
8.8.8.0/24 4777 15169
64.233.160.0/19 4777 15169

と，確かに8.8.8.8, 8.8.4.4はあるのだけど，その上にある4.3.2.0/24が気になる．試しに 4.3.2.1にpingしてみると応答があった．

4.4.4.4もキリ番だけど，これは誰かが既に使っているのかな？