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There are some interesting results from the Japanese earthquake of March 11th 2011. According to http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/usc0001xgp.phpl  the big (8.9) one was Friday, March 11, 2011 at 05:46:23 UTC.

PingER results

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 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.

53cottrell@pinger:~>ping www.tohoku.ac.jp
ping: unknown host www.tohoku.ac.jpExit 2

Also www.jp.kek although responding on 3/10/2011 it was no longer responding at noon 3/11/2011.

60cottrell@pinger:~>ping www.jp.kek
ping: unknown host www.jp.kek
Exit 2
64cottrell@pinger:~>ping 130.87.104.107
PING 130.87.104.107 (130.87.104.107) 56(84) bytes of data.
From 134.79.252.133 icmp_seq=31 Destination Host Unreachable
From 134.79.252.133 icmp_seq=58 Destination Host Unreachable

Japanese hosts seen From SLAC

Looking from SLAC there are big increases in the average RTTs and minimum RTTs for some Japanese sites (but not all). The spreadsheet gives more details.

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 see:

  • 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

It looks the problem is in the route to Japan not within Japan itself. I wonder if the undersea earthquake has disrupted some  cables? This appears to be in line with the information from http://www.renesys.com/blog/2011/03/japan-quake.shtm.

Routes

Comparing the routes from SLAC to RIKEN (ping.riken.jp) and from SLAC to NET.APAN.N2 (ns.jp.apan.net) we see RIKEN has more hops and goes Eastwards via the Avenue of the Americas in NY, while APAN goes directly via Sunnyvale near SLAC and then via Pacific Wave directly to Japan. The traceroutes from SLAC to the  University of OSAKA and the University of TOKYO  are similar to traceroute from SLAC to  RIKEN.

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