Example image of eyePlorer eyePlorer map for 'Public switched telephone network': Circuit switching Internet Internet Protocol Packet switching Telephone Analog signal Digital Landline Mobile phone Outside plant E.164 ITU-T Telephone number Quality of service Teletraffic engineering Agner Krarup Erlang Packet switched network X.25 Broadband integrated services digital network Disruptive technology Cable modem Digital subscriber line Fiber to the x Integrated services digital network Last mile Local loop Voice over Internet Protocol Gateway (telecommunications) Private branch exchange Telephone exchange Trunking Multi-frequency Pulse dialing Signaling System 7 Switchboard Two-wire circuit Bell Labs Digital Signal 0 S Called party Calling party Pulse-code modulation Protocol (computing) Routing in the PSTN Signalling (telecommunications) Time-division multiplexing Digital Signal 1 E-carrier T-carrier Access network