The terrorist attacks resulted in what could be the worst performance degradation of the Internet's history as millions of users scrambled to access online news.
Many of the most popular news sites were unavailable for as much as an hour after the attacks Tuesday morning. Later in the day many Web sites, such as CNN.com and MSN.com, were available but in stripped down versions offering only text and still forcing users to wait much longer than usual for pages to load.
The Internet's performance was affected more than during the California energy crisis, the Code Red worm, the Baltimore train disaster or other natural disasters, according to statistics gathered by Mercury Interactive Corp., a Sunnyvale, Calif.-based company that monitors and measures Internet performance.
"What we're really looking at is the worst web performance in the United States that we have seen," said Diane Hagglund, Mercury director of product marketing.
On a normal day, Mercury's Internet "weather map" will record only a handful of connections it measures from 100 nodes that are running in the red zone, or less than 10 kilometer per millisecond, she said. On Tuesday, the company measured 40 to 50 connections that were running in the red zone.
Although the Internet backbone infrastructure was not significantly affected, the major news sites experienced the most significant performance decline on Tuesday, according to Keynote Systems Inc., a San Mateo, Calif.-based company that measures Internet health.
CNN.com, NYTimes.com, and ABCNews.com were unavailable for an hour immediately following the attacks, according to Keynote's Internet health report.
USAToday.com declined to 18 percent availability and MSNBC.com to 22 percent availability, according to the report. The FBI's home page is the only web page that experienced as much degradation as the major news sites, said Bill Jones, senior director of public services at Keynote Systems. The FBI's web site lagged for almost 2 minutes to load a page, Jones said.
To reduce the impact to their servers, most of the news sites reduced the size of their home page by eliminating graphics by noon on Tuesday, Jones said. For example, CNN.com's home page before the event was in excess of 255 kilobytes; afterwards it was reduced to about 20 kilobytes.
The NewsOK news Web site, a combined effort between The Oklahoman newspaper and KWTV News 9, also was overwhelmed by the demand for news on the terrorist attacks, said Dan Barth, CIO, The Oklahoma Publishing Company, based in Oklahoma City, Okla.
"We're pulling off ads to get more capacity [to allow for greater access to the site]," Barth said on Tuesday. Many more people than expected were using it as a news source, he said.
The recently launched Web site was set up to initially handle a 5MB capacity, "but we're peaking at 10MB," Barth said. "We're looking at how we can get more capacity."
"Having lived through the Oklahoma City bombing, we're sensitive to this situation," Barth said.
Heather Harreld is an InfoWorld senior editor. Eugene Grygo is an InfoWorld associate news editor.