The FCC blamed T-Mobile for its nationwide network outage that occurred in June because it was not following established network reliability best practices. A staff report detailed the causes and impact of the outage along with remedies to prevent similar outages in the future.
“Our staff investigation found that the T-Mobile did not follow several established network reliability best practices that could have either prevented the outage or at least mitigated its impact,” FCC Chairman Ajit Pai, said. “All telecommunications providers must ensure they are adhering to relevant industry best practices, and I encourage network reliability standards bodies to apply their expertise to the issues identified in this report for further study.”
On June 15, 2020, T-Mobile experienced an outage on its wireless networks that lasted over 12 hours, disrupting calling and texting services nationwide, including 911 service, as well as access to data service in some areas. In the report, the FCC’s Public Safety and Homeland Security Bureau estimated that at least 41 percent of all calls on T-Mobile’s network failed during the outage, including at least 23,621 failed calls to 911.
T-Mobile’s outage was caused by an equipment failure and exacerbated by a network routing misconfiguration, according to the bureau. The outage was also magnified by a software flaw in T-Mobile’s network that had been latent for months and interfered with customers’ ability to initiate or receive voice calls during the outage.
In its report, the bureau identified network reliability best practices that could have prevented the outage or mitigated its effects, including providers periodically auditing the diversity of their networks. The bureau also recommended several network reliability issues for further examination by standards bodies.
In keeping with past practice, the bureau plans to release a public notice, based on its analysis of this and other recent outages, reminding companies of industry-accepted best practices, including those recommended by the FCC’s Communications Security, Reliability, and Interoperability Council, and their importance. In addition, the bureau will contact major transport providers to discuss their network practices and offer assistance to smaller providers to help ensure that our nation’s communications networks remain robust, reliable and resilient.