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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 |
| |
ns.osaka-u.ac.jp | JP.U-OSAKA | Osaka |
| |
ping.riken.jp | JP.RIKEN | Wako-Shi |
| |
www.u-tokyo.ac.jp | JP.U-Tokyo | Tokyo |
| |
ns.jp.apan.net | NET.APAN | Tokyo |
|
The map below shows the location of the hosts.
Immediate impacts of earthquake on Japanese hosts seen from SLAC
All of the 6 hosts that PingER monitors in Japan stayed up at the time of the earthquake.Looking from SLAC there were big increases in the average RTTs and minimum RTTs for some Japanese sites (but not all), see below. The [spreadsheet|^japan-earthquake.xlsx] gives more details.
Further pinpointing of causes for increased RTTs
RIKEN seen from the world
Looking at RIKEN (a monitoring mode and so easy to select on and also one of the most affected as seen from SLAC) seen from the world looking at avg RTT and min RTT we saw:
- No effect seen from Africa, E. Asia, Europe, L. America, M. East
- Big effect from N. America (Canada 163ms=>264ms, US 120ms=>280ms)
- India CDAC Mumbia no effect, Pune 380ms=> 460ms, VSNL Mumbia 360ms=>400ms
- Sri Lanka no effect
- Pakistan (we have lots of monitors so should be interesting).
- NIIT sees no effect (nb not on PERN)
- The PERN (Pakistan Education and Research Network) nodes starting with 111. (apart from UAAR see later, this needs more investigation) see 420ms=>500ms
- The PERN nodes starting with 121. See no effect
Conclusion It is not the site RIKEN that has gone bad, rather it is some of the routes
RIKEN Looking at Japan
Japanese hosts seen from JP.RIKEN.N3 (RIKEN) see no impact on RTT
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