This BBC article looks at the sophisticated understanding the Iranian government has of media, its domestic and foreign strategies, and how bloggers are the biggest dissident threat despite the most sophisticated Internet filtering system this side of China.

Some excerpts:

Broadcasting is run by the authorities. It reflects the views of the Supreme Leader Ayatollah Ali Khamenei and his allies in the conservative clerical establishment.

There are no private, independent broadcasters allowed to operate inside the country.

The internet has provided a big challenge for the Iranian authorities in its efforts to control information

The Islamic Republic of Iran Broadcasting controls TV and radio. It is dominated by conservatives, and has often been criticised by Iranian reformists for its conservative bias.

It often ignored the activities and statements of the former president - and reformist leader - Mohammed Khatami. In recent elections, reformists criticised state TV and radio for blatantly favouring conservative candidates.

But state TV and radio are not the only broadcasters available in Iran. Satellite ownership may be illegal, but the law is only intermittently enforced.

The result is that Iranians can see and hear non-state controlled media from outside the country. ...

On the international stage, Iran tries to combat other media sources with its own relatively advanced satellite and radio stations. The most significant of these is Al Alam - The World - a 24-hour news channel in Arabic ...

But it is not the only TV station broadcasting from Iran to the outside world.

Iran's rulers have invested heavily in such channels - one broadcasts specifically to the Iranian diaspora; another, Sahar TV, broadcasts in a variety of languages, including English, French, Kurdish and Urdu.

A state-run radio station also broadcasts in about 30 languages. And that's not to mention the Lebanese channel, Al Manar - known as Hezbollah TV - which has received Iranian support.