Iran is once again cutting its citizens off from the internet in advance of the country’s parliamentary elections. According to reports circulating this morning, the country has blocked most secure socket layer – SSL – connections. That cuts off anything that uses “https” protocols, including most email services, YouTube, and social networks like Facebook and Twitter.

According to a Reuters report this morning, VPN software, which is commonly used by Iranians to bypass the country’s censorship efforts, have also stopped working. Early last week, reports started surfacing that Iran had been blocking access to several email and social networking sites for several days. Google (including Gmail), YouTube, and Facebook were among the sites that were cut off, while Twitter seems to have been left alone, for the most part. The restrictions were apparently lifted just a few days later.

This latest outage appears to be related to the upcoming parliamentary elections, which are scheduled for March 2. This will be the first time Iran has held national elections since the presidential election of 2009. That election, which current president Mahmoud Ahmadinejad won by a suspiciously large margin. Suspicions of fraud prompted Mir-Hossein Mousavi, the rival candidate, to call on his supporters to engage in non-violent protests. The resulting demonstrations were massive and widespread, lasting several weeks. Social networking sites like Twitter played a major role both in organizing the protests and in getting news about what was going on in Iran to the outside world. It is likely that the current round of internet blockage in Iran is geared toward preventing a repeat of those events.