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.
Overview:
Internet connectivity to the hosts PingER monitors in Japan was maintained. Round Trip Times (RTT) to some hosts increased significantly as seen from SLAC. However as seen from RIKEN in Japan they did not increase. It appears the increase in RTT depends on the route from the monitoring host to Japan. This suggests a possible cable disruption.
While the Internet appears to have kept running remarkably well, the phone network did not fare so well.
PingER results
All of the 6 hosts that PingER monitors in Japan stayed up at the time of the earthquake. The hosts monitored are seen in the table below.
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Tohoku University (www.tohoku.ac.jp), which we were not monitoring previously, on the outskirts of Sendai and close to the earthquake was not responding on 3/12/2011 12:46pm PST.
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