In a 2007 report, the OpenNet Initiative said that “the Islamic Republic of Iran has installed one of the most extensive technical filtering systems in the world”. Iran requires all internet providers to go through state-controlled gateways, and internet providers must employ filtering software. Reformist party websites, photo-sharing site Flickr, foreign blog hosting sites and social networks such as Facebook are often blocked in Iran.

Sophisticated users are able to route through alternate pathways or proxies to bypass government controlled gateways. Information about open proxies is being passed around on micro-blogging service Twitter to allow Iranian internet users unfettered access to the internet, but this is often a cat-and-mouse game. Government censors block the proxies as soon as they become aware of them.