With parliamentary elections scheduled for next week, Iran has begun blocking Internet services, Web security experts say, adding to concerns that government leaders hope to shut off Iranians from the rest of the online world.
The Tor Network, which provides free software for anonymous use of the Internet, reported that on Feb. 9, Tehran began filtering keywords and throttling or shutting down access to sites that use a form of security called Secure Socket Layers, or SSL. The protocol, which encrypts data being sent back and forth between servers and users, is used by such popular sites as Gmail and Facebook. Web addresses protected by SSL begin "https," instead of "http."
Activists in repressive countries often use Tor services to get around such restrictions, and before Feb. 9, Iranians were the second-largest users of Tor. But because Iran targeted the core SSL protocol, "Tor stopped working too," the organization said.
The action is blocking email and some Web access for as many as 30 million Iranians who use SSL-protected sites, reported CBR Systems & Network Security, a European technology organization.
Iran, which will hold parliamentary elections on March 2, has referred to Google and other search engines as "spying tools," and it has throttled access to foreign web servers previously at politically sensitive times. The free-expression activist group Reporters Without Borders has branded Iran as an "enemy of the Internet." (.pdf)
Iran's Communications and Technology Minister Reza Taghipour said Monday that a firewalled "national Internet," which Tehran has been promising since as early as 2006, would be launched in the spring. Internet security analysts and open-Internet activists say the "national Internet" would act as a closed intranet sealing Iranians off from large chunks of the web. Similar systems are known to be in use in China and North Korea.
The Iranian news agency Mehr quoted Taghipour as saying at a cyberdefense forum in Tehran that "the first phase of this network will become operational in the month of Khordad," which straddles May and June.
The Tor network said it was continuing "to research and investigate solutions with the assumption that SSL will eventually be blocked nationwide inside Iran."
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