They probably have not chosen to do that because such a move could impact commerce, Labovitz said. While other countries such as Burma in 2007, "completely unplugged the country during political unrest, Iran has taken a decidedly different tact," he said.

A macro-level analysis by Arbor of Internet traffic touching Iran shows how the state-owned Data Communication Company of Iran (DCI), which acts as the country's Internet gateway, severed most its Internet connections for a brief period of time on June 13th.

The move resulted in Iran literally dropping off the Internet for some time with all six of the upstream ISPs connecting Iran to the rest of the world "reporting a complete loss in traffic," Labovitz said in a blog post yesterday.

That move was probably an attempt by Iranian authorities to further centralize and consolidate traffic flows in and out of the country in an attempt to exercise better control over it, he said.

James Cowie, chief technology officer at Internet monitoring firm Renesys Corp., which has also , said that all Internet routes into Iran have basically remained open so far, except for the brief outage on June 13.