American neo-Nazi Scott Rhodes spoofed the CLIs of 4,959 calls that promoted his website and beliefs.
This is not the first time CenturyLink has paid the penalty for outages that stopped callers reaching 911 emergency services.
Outgoing FCC Chairman Ajit Pai claimed to be acting decisively by reminding telcos to do things that he already told them to do.
The FCC issued the penalty to an Arizona business that made 2.3mn spoofed robocalls, but Commissioner Geoffrey Starks noted the poor record for collecting similar fines.
The FCC said a cascade of failures would have been prevented if T-Mobile USA had periodically audited the diversity of their networks.
Several clues in the FCC’s latest report hint at the perverse logic behind STIR/SHAKEN.
Lisa Fowlkes of the FCC’s Public Safety Homeland Security Bureau says US wireless telcos are proactively improving the security of Diameter signaling.
An FCC order means traffic may be blocked if reasonable analytics suggests it would not be wanted by the recipient.
AT&T first withheld payment from LEC-MI in 2013, but mediation dragged on as they argued about LEC-MI’s liability for its agents.
Nuisance robocalls have fallen in the USA as billions of voice calls are now blocked automatically.