An analysis of the traffic patterns coming out of the Data Communication Company of Iran (DCI), Iran's state-run Internet provider, shows that the country has severely curtailed SSH, Flash and Bittorrent communications, a security researcher stated on Thursday.

Video, e-mail and Web traffic all showed spikes on the day of the Iranian election, but after that, those forms of data were increasingly filtered, Craig Labovitz, chief scientist for Arbor Networks stated in a blog post. SSH communications, Flash videos, and the Bittorrent protocol appeared to be filtered more than 80 percent of the time, according to data from the Internet Observatory.

"While the rapidly evolving Iranian firewall has blocked web, video and most forms of interactive communication, not all Internet applications appear impacted," Labovitz said. "Interestingly, game protocols like Xbox and World of Warcraft show little evidence of government manipulation."

The crackdown on news and information flows comes after Iranian president Mahmoud Ahmadinejad defeated rival Mir Hussein Moussavi in a contested election. Traditional news organizations have had their reporting ability curtailed by Iranian authorities, leading more Iranian dissident groups to use social networks to get reports, photos and video to the world outside of Iran. Protests within the country have turned violent, with at least eight people killed, according to media reports.

Following the crackdown on Internet communications, which reduced the traffic coming out of Iran to a trickle for a number of hours, distributed denial-of-service attacks took down several government Web sites.

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