Iranian opposition groups say that with the government cracking down hard on social notworking sites they are having to use emails to organise protests.

Information is coming through anonymous email set ups for times and places of possible rallies. The emails talk of possible rallies on February 11, when Iran marks the 31st anniversary of the Islamic revolution. Social media sites were hailed in the West as promising opposition supporters an anonymous rallying ground especially when they were accessed via proxy servers.

The authorities have slowed Internet speeds and shut down opposition websites.They also boast of an ability to track online action even from behind the proxies. While this might not be true, the Iranian government has got very good at filtering and blocking sites. Iran's government has also been buying monitoring technology, which enables it to detect computers making a secure connection.

Mikko Hypponen, chief research officer for Helsinki-based F-Secure Corporation said that some proxy servers use Secure Sockets Layer (SSL) to secure the connection with a remote server. This security layer helps ensure that no other computers can read the traffic exchanged. But when people make these SSL connections the authorities cannot see the content of material accessed.

However they can and are physically raiding sites to check on the computers involved.