March 911 Outage Affected More Than 12,000 Callers

By Ryan Knutson 

More than 12,000 AT&T Inc. wireless customers couldn't get through to 911 during a five-hour outage earlier this month, federal regulators said Thursday.

The outage occurred on March 8, starting in parts of the central and eastern U.S. before spreading to the rest of the country, said Lisa Fowlkes, acting head of the Federal Communications Commission's public safety and homeland security bureau, during an FCC meeting. The commission is investigating the incident and called for "interested parties to submit information concerning the cause, effect and implication" of it.

The outage occurred after AT&T made changes to its network that caused automatic 911 routing to fail, Ms. Fowlkes said. The failure primarily affected calls made via Voice Over Long Term Evolution, or VoLTE, a digital calling technology frequently running on smartphones.

Some calls were routed manually by a backup center, but the volume quickly exceeded its capacity, resulting in a large number of calls being dropped, Ms. Fowlkes said. During the outage, callers heard either a fast busy signal, ringing with no answer, or no sound at all.

AT&T said it was addressing the issue and would continue to work with the FCC as it completes its investigation.

The Dallas telecommunications company suffered a separate 911 outage on March 11 that was caused by a hardware failure, but only a small number of people were affected, Ms. Fowlkes said.

The outage is among a string of recent, high-profile 911 problems. In October, 911 suffered what experts believe is the largest cyberattack ever against it. Also last fall, a 911 center in Florida was overrun with robocalls from telemarketers. Dallas residents have also been dealing with long wait times when calling 911 due to staffing and technical problems.

Write to Ryan Knutson at [e-mail]

(END) Dow Jones Newswires

March 23, 2017 14:52 ET (18:52 GMT)

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