- 25 Feb 08, 14:30 GMT
Just before Darren Waters broke the story about YouTube's outage last night, I was fielding calls from friends questioning my technical competence. I had posted a video of a recent ski-ing holiday on YouTube, and emailed the link to my fellow skiers - only to hear from them that the video just wouldn't play.
So I was rather relieved to discover that it was a global outage - rather than my incompetence - which was frustrating my friends and millions of other YouTube users. At first Google told me it was unlikely to have anything to do with Pakistan, or the row over alleged anti-Islamic material on the site.
But by this morning YouTube's owners had decided otherwise - and released this statement:
"For about two hours, traffic to YouTube was routed according to erroneous Internet Protocols, and many users around the world could not access our site. We have determined that the source of these events was a network in Pakistan. We are investigating and working with others in the internet community to prevent this from happening again."
Hmmmm - well I'm not sure that makes it a lot clearer. But here is how a spokesman from the London Internet Exchange - which handles huge amounts of internet traffic - explained it to me, with great patience.
So the Pakistani authorities order the country's ISPs to block access to YouTube. That is done by the country's telecoms provider sending out what is, in effect, a new - and false - route to get to YouTube. The result is that any traffic from Pakistani users to YouTube gets directed into a cul-de-sac. So far, so normal, for any country - China, Turkey, Iran - which decides to control its population's access to certain websites.
But what appears to have happened in this case is that the dodgy route map somehow leaked beyond Pakistan's borders, and was adopted by the giant Asian telecoms business PCCW. Once it started broadcasting this new way to find YouTube, the rest of the world's ISPs altered their maps, sending everyone up the wrong road.
Which all raises some interesting issues. The internet is an open self-correcting mechanism which runs on trust - if someone announces a new route to YouTube, others will take it as read that they are acting in good faith.
What we need to know now is whether this was a mistake or a deliberate attempt by Pakistan to disrupt YouTube beyond its own borders. Google still isn't sure - but it must now be aware that it and other global businesses are vulnerable to attacks from hostile governments.
A decade ago it was widely assumed that the internet would defeat attempts by governments to control freedom of speech and thought. But in this latest encounter the score looks like Government 1 - Internet 0.
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