In the early 1960s, AT&T introduced a method of providing in-band signaling so telephone customers could place telephone calls. The system was called dual-tone multi-frequency, or DTMF. AT&T, through ...
A practical look at Dual Tone Multi Frequency and RFC 2833/4733 It's easy to get lost in the technological babble of our industry. We are awash in acronyms, product names, standards (real and pseudo), ...