Performance measurements by Keynote Systems showed significant drops in availability and increases in Internet response time around the world in the overnight hours, with the worst disruption around 2 a.m. eastern standard time. Some Web sites were unreachable and service was shut off for some users, says Keynote, which monitors Internet and E-commerce performance. Level 3 did not return phone calls seeking comment on the disruption. Keynote also showed extensive performance degradation on the networks of NTT Communications subsidiary Verio. An NTT spokeswoman says those access problems may have been related to Level 3's problems.
Level 3 is among the largest providers of wholesale service to ISPs in North America, connecting millions of customers to the Internet. Earlier this month, the company was involved in a spat with fellow provider Cogent Communications that blocked access for thousands of users over a two day period. One Level 3 customer says his company's had outages before. "It shouldn't happen this often for a tier one ISP, and it concerns us," says David Geller, president and CEO of WhatCounts Inc., an E-mail marketing firm, via E-mail. "It impacted all of our customers in that our site and tools were inaccessible for several hours."
Disruptions this widespread are unusual. "I don't think I've ever seen an entire backbone network go down like that before," says George Roettger, Internet security specialist for NetLink Services Inc., a provider of Internet access for the greater Ohio and surrounding areas, via E-mail.
Nevertheless, businesses would be well served to look deep into redundancy plans and understand in detail who their underlying service providers are, Forrester Research analyst Brownlee Thomas says. Says Thomas, "You only wake up to the need for physical diversity when something happens to you."