Iran's firewalls tightened ahead of election

As Iranians head to the polls, the existing government has tightened its grip on the internet and even turned its firewall against politicians close to the current rulers, say researchers who have detected a shift in the kind of sites blocked over the last two weeks. But a total shut down of the web on election day - rumoured last week - has so far failed to materialise.

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An old article but a frightening vision of what a government can do to consolidate its power with a secret net filter.