Today some of Google's services were unavailable to a small percentage of users, causing problems with all of their services including YouTube, Gmail, Google Analytics, Google Maps and Google Docs.
Some speculations that AT&T was the root cause of it, but was later denied via twitter that it was not responsible. McAfee argues that the problem was caused by a IPv6 upgrade, but Google failed to respond to that issue.
The exact cause of the issue is not certain as Google's official statement didn't give exact details about the outage. The official statement claims that all of the traffic was routed through Asia causing a traffic jam and slowdowns or outages for many users.
Google posted this official statement about the outage:
"Imagine if you were trying to fly from New York to San Francisco, but your plane was routed through an airport in Asia. And a bunch of other planes were sent that way too, so your flight was backed up and your journey took much longer than expected. That's basically what happened to some of our users today for about an hour, starting at 7:48 am Pacific time.
An error in one of our systems caused us to direct some of our web traffic through Asia, which created a traffic jam. As a result, about 14% of our users experienced slow services or even interruptions. We've been working hard to make our services ultrafast and "always on," so it's especially embarrassing when a glitch like this one happens. We're very sorry that it happened, and you can be sure that we'll be working even harder to make sure that a similar problem won't happen again. All planes are back on schedule now."
The issues have since been fixed worldwide and all servers restored.