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"We initially stated that Sudan’s outage began at 12:47 UTC because
that because that was when virtually all Sudanese routed networks were withdrawn
from withdrawn from the global routing table. However once we plotted our active data measurement data, we observed traffic into Sudan dropping off dramatically 2.5 hours earlier at 10.23 UTC"
See http://www.renesys.com/2013/09/internet-blackout-sudan/
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