Via Renesys (via Cryptogon, who suffers so with us foolish mortals, the poor thing), an explanation why Iran is not totally disconnected from the internet as well as an explanation of how the story got legs:
But then there was this Slashdot posting, claiming Iran had zero connectivity. This was news to us. It’s said that “the first casualty of war is truth.” Something similar can probably be said with regard to catastrophic failures. Truth might not be first, but it is a very close second. Journalists are pushed to meet deadlines for stories about topics for which they have little familiarity, and technical experts sometimes jump to conclusions on the basis of little evidence. It’s not hard to see why the truth gets distorted; it’s hard to think clearly when you believe the sky is falling.
The Slashdot claim was made since a web page at the Internet Traffic Report was reporting that the country was down. This report seems to be based on pings to a single router in Iran from multiple places around the world, which at best only indicates that one router in Iran is unavailable, not that the entire Internet has ceased to function there. Of course, once something ends up “in print”, it tends to gain credibility and then be referenced by others. And before long, large numbers of people think it is actually true. (For a detailed ping analysis to the region during the outage, see this article.)
I am happy to post this and happy not to be worrying about Iran today. Call me sentimental, but the idea that innocent people were being set up for the kill just made me wig out a little. Sorry.
Of course, none of this means that the cables weren’t sabotaged, it just means that Iran was not specifically targeted in preparation for a military strike.
UPDATE: Analysis and speculation at Emptywheel. Thanks malc.

#1 by malcontent on February 4, 2008 - 12:17 pm
Depending on the router it can indeed mean the entire country is isolated from the Internets.
Just because a site responds, it doesn’t necessarily mean anything with regard to a service outage in Iran. If I were to design disaster recovery for a business in Iran the first thing I would do is establish a server farm out of the country, probably eastern Europe or Russia, to pick up services when things like this happen. The world’s only remaining superpower is waving a sabre in your face constantly so this is not an unreasonable or even far fetched risk strategy to survive as a commercial entity through the uglier side of war (the non-American side).
That server farm responds in your stead as if it is you by design. Despite the fact that all 4 OC-768’s into Iran are suddenly dark.
Logistics of a line like this are characterized here if you like geekspeak:
http://spiedl.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=OPEGAR000044000002025004000001&idtype=cvips&gifs=yes
Of course I am not really sure what kind of lines these are yet but I’ll keep digging.
#2 by Marlena on February 5, 2008 - 3:40 am
I’m over my head understanding the technology side of this, no doubt. The Renesys blog might make a lot more sense to you.
The other thing that’s making sense is the Iranian Oil Bourse. Slowing that down may be the real target.