Syrian Arab Republic (the)
The first observed disruption, between 01:00 – 05:30 GMT on June 9, took place in conjunction with 712,000 university students starting their second term exams, along with 9th grade (O-Level) and 12th grade (A-Level) students starting public exams as well. Additional disruptions were also seen on June 11, 13, 17, and 19, all effectively appearing as complete country-wide outages in the Oracle Internet Intelligence, CAIDA IODA, and Google Transparency Report Traffic figures below.
It is interesting to note that within the Oracle Internet Intelligence Map graphs, the Traceroute Completion Ratio and BGP Routes metrics drop to zero during the periods of disruption, but the DNS Query Rate metric spikes. Doug Madory, Director of Internet Analysis at Oracle Internet Intelligence, explained why this happened:
Since they don't modify the routing for outbound traffic, we observe a surge in DNS queries as computers in Syria repeatedly try in vain to resolve domains – the responses are sent by DNS operators but never arrive, so they retry and retry.https://t.co/DJr2IKeaxE pic.twitter.com/BMvhQlUU8N
— Doug Madory (@DougMadory) June 10, 2019