Pertaining to establishing a connection to the Internet over the public switched telephone network (PSTN) by dialing the telephone number of an Internet service provider (ISP).The term implies the use of an analog local loop and a modem or ISDN service and a terminal adapter (TA). Note: A dial-up connection usually involves dialing the number using a telephone equipped with a keypad, rather than a dial. See also analog, dial, Internet, ISDN, ISP, keypad, local loop, modem, PSTN, and TA.