Major Internet backbones and Web sites were not affected by Thursday afternoon's massive power outage in the Northeast as of 9:57 Thursday evening, according to Keynote Systems.

Keynote's monitoring of all major U.S. Internet backbones from the 25 largest U.S. metropolitan areas have not shown any difficulties during the outage, and major Web sites remained accessible and at their normal performance levels. A few news sites, such as www.usatoday.com and www.cnn.com, had minor performance and availability problems during the initial phases of the blackout. Such performance issues often result from heavy workloads during major news events. The two news sites rapidly recovered and returned to excellent performance.

"As is true of the telephone system, the Internet and major Web sites have been engineered with redundancy and backup power systems to withstand power outages," said Eric Siegel, principal Internet analyst at Keynote. "It's not surprising that a power outage, no matter how widespread, didn't appreciably affect the Internet and the Web. As long as there isn't major physical damage, such as that caused by the July 2001 Baltimore tunnel fire, or major congestion, such as that caused by the SQL Slammer worm in January 2003, the Internet and the Web have enough redundancy and resilience to withstand most problems."

Internet performance is displayed in real-time on the Keynote Internet Health Report, which is a standard tool used by major Internet Service Providers. The free version of that report is available at http://www.internethealthreport.com