Syria's tether to the digital world appears to have been severed, cutting off Internet access to and from the country entirely. In addition to an apparent Internet blackout, Syrians may also be facing isolated landline and cellular phone service disruptions according to the Associated Press and a growing number of unverified reports (e.g. #SyriaBlackout).
Update (12/1): CNN informs that voice communication and Internet service has been reestablished in most regions of the country. The news come about 48 hours after the blackout, as reported by the Syrian Observatory for Human Rights. The original story follows below.
Around 5:26 AM EST, Syrian Internet traffic ceased with all 84 IP blocks assigned to the country becoming unreachable. Internet research firm Renesys was first to report the incident. Since then, Akamai and Google have corroborated the company's findings amidst various reports of service disruptions and real-world tumult.
The exact cause is unknown, but many speculators presume the communications blackout is a government-led attempt to halt the spread of information and disadvantage Syrian rebels. However, according to Reuters, a pro-government television station has reported that Syria's minster of information blames "terrorists" for the Internet blackout -- presumably rebel forces.
It's worth noting that this is not the first time that Syria has gone dark. In June 2011, the Syrian government pulled the plug on most of the country, leaving only select few government-owned network prefixes active. The outage lasted for about a day and included at least one 3G-capable cellular provider.
The outage coincides with a tense battle between rebels and loyalists just outside Damascus, a fight which has blocked access to an International airport. "Rebels and activists said the fighting along the road to Damascus airport, southeast of the capital, was heavier in that area than at any other time in the conflict.", reports Reuters.
In the past, other governments have shut down Internet access in order contain the flow of information inside and outside their geopolitical borders. Such blackouts also slow the ability of protesters and opposition forces to communicate and organize. A recent example of this was a five-day blackout in Egypt which was used to snuff out media coverage of protests challenging President Hosni Mubarak. During this time, Google introduced a speak-to-tweet service which allowed Egyptians to send tweet via telephone.