"403 Forbidden": that's what Ars readers in Iran are now seeing when they try to connect to arstechnica.com. We were alerted to the block by a loyal Iranian reader late last week, and we checked our traffic statistics over the weekend; we do, in fact, appear to be banned.

The block began following our second piece of coverage about the Stuxnet malware that allegedly targeted an Iranian power plant. That was published on September 27, the last day in which Iranian readers could access the site, as you can see from the second spike on the graph above. After that, traffic from Iran drops to zero. Our Iranian readers say that this is what they get now when they try to visit the site, which we are told is the standard response returned by the Iranian government's filter when users try to access a blocked site.

The point of the ban isn't clear, but it definitely highlights how easy it is for governments to start cracking down on whatever sites they like once they have the proper tools in place and have centralized all Internet links leaving/entering the country. And, as the traffic logs show, it can be surprisingly effective at discouraging casual users from viewing unwanted content.

What else has Iran blocked recently? We would ask our Iranian readers to let us know, but—sadly—they may have a hard time reading this post.