(Reuters: A Free Syrian Army fighter aims towards Aleppo's historical citadel controlled by snipers loyal to Syria's President Al-Assad)
The stunning visualizations of Syria's Internet blackout, now in its second day, keep rolling in.
Below is web security/performance company CloudFlare's view of Syria's network routes being withdrawn, as recorded by one fo the company's network engineers. Syrian Telecommunications is represented by the red dot in the center of the video and other lines depict routes to upstream providers.
Here's CloudFlare's technical explanation of what appears to have happened in Syria, where government and rebel sides have swapped blame for the blackout:
To begin, all connectivity to Syria, not just some regions, has been cut. The exclusive provider of Internet access in Syria is the state-run Syrian Telecommunications Establishment. Their network AS number is AS29386. The following network providers typically provide connectivity from Syria to the rest of the Internet: PCCW and Turk Telekom as the primary providers with Telecom Italia and TATA for additional capacity. When the outage happened, the BGP routes to Syrian IP space were all simultaneously withdrawn from all of Syria's upstream providers. The effect of this is that networks were unable to route traffic to Syrian IP space, effectively cutting the country off the Internet.
Syria has 4 physical cables that connect it to the rest of the Internet. Three are undersea cables that land in the city of Tartous, Syria. The fourth is an over-land cable through Turkey. In order for a whole-country outage, all four of these cables would have had to been cut simultaneously. That is unlikely to have happened.