Example image of eyePlorer eyePlorer map for 'Signalling (telecommunications)': Telecommunication Information Information transfer Telecommunication circuit Telecommunications network User (telecommunications) Message Public switched telephone network Dual-tone multi-frequency Telephone line Channel (communications) Signaling System 7 Answer supervision Disconnect supervision Line signaling Supervision 2600 hertz Band-stop filter Long distance E-carrier Robbed-bit signaling Register signaling Telephone number Telephone Telephone operator Pulse dialing Rotary dial B channel Channel Associated Signaling Common Channel Signaling Compelled signalling Multi-frequency R2 signalling Telephone exchange SS7 Metering pulse Payphone E and M signaling Bell System Ground start Loop start Adjacent-channel interference Alternative frequency Anisochronous Balun Bipolar signal Blanketing BORSCHT Busy signal CDMA2000