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None of the 6 hosts that PingER monitors in Japan went down for an extended period of time at the time of the earthquake. the The hosts monitored are seen in the table below.
IP name | Alias | City | Institution |
|
|---|---|---|---|---|
glbb.jp | JP.GLBB | Okinawa | Speedtest |
|
www.kek.jp | JP.KEK | Tsukuba | KEK |
|
ns.osaka-u.ac.jp | JP.U-OSAKA | Osaka | Osaka University |
|
ping.riken.jp | JP.RIKEN | Wako-Shi | RIKEN |
|
www.u-tokyo.ac.jp | JP.U-Tokyo | Tokyo | Tokyo University |
|
ns.jp.apan.net | NET.APAN | Tokyo | APAN |
|
However as can be seen from the map below, we were not monitoring a Japanese host near the epicenter. 
Tohoku University (www.tohoku.ac.jp), which we were not monitoring previously, on the outskirts of Sendai was not responding on 3/12/2011 12:46pm PST.
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