DTMF masking (also known as DTMF suppression or DTMF clamping) works and how a secure payment solution such as CardEasy that uses DTMF masking is the most secure and PCI compliant way to take payments ...
DTMF stands for dual tone multifrequency. Each key on a telephone keypad generates a unique DTMF tone when pressed. These tones are transmitted over the voice channel and equipment at the receiving ...