An apparatus, related devices and methods, having a memory element operable to store instructions; and a processor operable to execute the instructions, such that the apparatus is configured to identify, on an electronic device, a phone number of an incoming caller device; request, via an out-of-band control channel, a digital certificate for the phone number from the incoming caller device; receive, via the out-of-band control channel, the digital certificate for the phone number from the incoming caller device; determine whether the digital certificate for the phone number is authentic; and indicate, on the electronic device, based on a determination that the digital certificate for the phone number is authentic or not authentic, whether the phone number is authentic or not authentic.