A combination of a fiber optic cable cut and malfunctioning backup system on Sprint's network caused a brief loss of phone service in St. Louis and intermittent troubles across a swatch of Midwestern states Thursday afternoon.
Sprint officials said the trouble started around 8 a.m. CDT, when a backup system for routing telecommunications traffic between Chicago and Bloomington, Illinois, stopped working, presumably because of a computer glitch.
The backup system failure on its own wasn't enough to bring down the network. However, the problem intensified around 1 p.m., when a cut on a fiber optic line between Kansas City and Jefferson City, Missouri, halted traffic on the main network.
For about 20 minutes following the cable cut, Sprint customers in the St. Louis area couldn't make or receive calls. The failure also affected customers between Chicago and Kansas City, who experienced intermittent trouble making and receiving calls.
Sprint said it repaired the backup system by 3 p.m., and that traffic has been moving smoothly since. The company didn't say when the fiber cable would be repaired and said it hasn't determined the cause of the cut.
