T-Mobile US confirmed that it suffered a network outage during the weekend, which appeared to affect customers' ability across the country to make voice calls over Wi-Fi and LTE.
Details remain unclear on the outage, including how many customers were affected and what the reason was behind the problem. Based on some anecdotal evidence on social media, T-Mobile customers across the country could not make or receive phone calls over either their own Wi-Fi networks or over T-Mobile's LTE network, which may have been due to T-Mobile's Voice over LTE technology.
"Right now we are experiencing service issues going on with LTE and Wi-Fi calling," T-Mobile tweeted Sunday though its customer service Twitter account. "This is affecting everyone, so we're working around the clock to make sure we get this up and running as soon as possible."
T-Mobile became the first major U.S. carrier to launch VoLTE in May 2014, when it offered only three supporting handsets. Late last year, the carrier said that nearly 40 percent of voice calls on T-Mobile's network were transmitted via VoLTE -- a noteworthy statistic considering that, just a month earlier, T-Mobile said roughly 33 percent of voice traffic was routed through VoLTE.
Other carriers including AT&T and Verizon have since launched their own VoLTE services.
T-Mobile's troubles didn't go unnoticed by its competitors. Sprint CEO Marcelo Claure, who Legere has taunted over Twitter in the past, tweeted the following Sunday: "Hey @JohnLegere I understand @TMobile network is down. In troubled times colleagues help each other.I can send my LTE + engineers to help out."
Of course, T-Mobile isn't the only carrier to suffer a service outage. AT&T recently reportedly suffered a network outage in Idaho. Last year T-Mobile US experienced a service disruption for several hours across a wide swath of the Northeast. In 2013, AT&T Mobility's prepaid brand Aio Wireless suffered a service outage. And Verizon's network suffered a series of service troubles shortly after the carrier first launched LTE.
A wide range of issues can affect wireless customers' experiences, including their phones, their distance from cell towers, and possible network interference. But a nationwide outage likely would be a result of problems inside a carrier's core network.
T-Mobile recovers from service disruptions in the Northeast
AT&T's Aio prepaid brand suffers service outage
Verizon restores service after LTE network falters again