The FCC announced the release of a report detailing the cause and impact
of a nationwide CenturyLink network outage that occurred last December,
along with recommendations to help prevent similar outages from occurring
in the future
https://www.fcc.gov/document/fcc-issues-report-centurylink-network-outage
December 27, 2018 CenturyLink Network Outage Report
In the early morning of December 27, 2018, CenturyLink experienced a
nationwide outage on its fiber network that lasted for almost 37 hours.
This outage was caused by an equipment failure catastrophically
exacerbated by a network configuration error. It affected communications
service providers, business customers, and consumers who directly or
indirectly relied upon CenturyLink’s transport services, which route
communications traffic from various providers to locations across the
country, resulting in extensive disruptions to phone service, including
911 calling. The effects included dropped calls, disconnected 911 call
centers (known as “Public Safety Answering Points”), and fast-busy signals
for people who called 911. As many as 22 million customers across 39
states were affected by the outage, including approximately 17 million
customers across 29 states who lacked reliable access to 911. Indeed, at
least 886 calls to 911 were not delivered.1 Fortunately, based on
discussions with affected service providers and public safety officials
from affected states, as well as a review of media reports, the Public
Safety and Homeland Security Bureau (Bureau) is not aware of any harm to
life or property resulting from the outage.
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