Severe disruption

Definition
Severe disruption is

"a sustained interruption or severe degradation of Internet service that could have potential strategic and/or service integrity significance to Government, industry, and the public. Such an event would likely affect Internet service in at least one region of the country, including at least one major metropolitan area. It would not only involve multiple Internet Service Providers (ISP) and significantly degrade the functionality of at least one critical infrastructure in the affected area, but also have an impact on the availability and integrity of Internet service for at least a significant portion of a business day."