Signaling in telecommunications is the use of signals to manage signaling network communications. This could be an information exchange about creating, administering, and controlling a communications circuit and network.
In-band signaling is the exchange of call control information over the same physical channel or frequency band that the actual phone call is using in a publicly switched telephone network (PSTN). Dual-Tone Multi-Frequency signaling (DTMF), which is utilized on the majority of phone lines to customer premises, serves as an illustration.