Denial of Service Attack Knocks Twitter Offline

Twitter was shut down for hours Thursday morning by what it described as an ongoing denial of service attack. In a one sentence statement on its status blog, Twitter said, “We are defending against a denial-of-service attack, and will update status again shortly.” The outage appeared to begin mid-morning, EST, and affected users around the world. In the early minutes of the outage, we confirmed it in two boroughs of New York and received word that it was down in Brazil as well. At that point, Twitter apparently didn’t know what had hit it. (The status blog read, at that point, “Site is down - We are determining the cause and will provide an update shortly.”) The world won’t come to a standstill as a result of the Twitter outage, of course, but its impact will surely be felt. The popular short messaging service has become an integral part of the communications ecosystem — our first question was, how do you confirm Twitter is down without Twitter? — and from its millions of inveterate users, we expect an outpouring of pent-up Tweeting when this gets sorted out. An extended outage could have an impact on the spread of information — videos, music, and articles like this one to say nothing of a growing number of businesses which depend on the service. We experienced a seemingly unrelated problem when accessing the Twitter blog through Google. The page greeted one Wired.com employee with an error message beginning “We’re sorry… but your query looks similar to automated requests from a computer virus or spyware application. To protect our users, we can’t process your request right now.” Another Wired.com employee was able to access the page as usual, with no virus warning. But with other users encountering the same error message, we wondered whether today’s Twitter outage was somehow related to Google’s virus warning. Judging from Twitter’s admission that it is under a denial-of-service attack, that appears to have been the case. Twitter hasn’t had a significant outage since May 8, and has shown improved reliability since last year, when such outages were a regular occurrence. The last scheduled maintenance we know about was on June 16 — delayed by a day at the urging of the US State Department. This was during the height of the anti-government protests in Iran, much information was being disseminated to the world via Twitter, and the maintenance window, in the middle of the night in California, would have been prime daylight hours in Tehran.