A 3270 Emulator is a computer program that duplicates the functions of an IBM 3270 mainframe computer terminal on a PC or similar microcomputer.
As the original 3270 series terminals were connected to the host computer using coaxial cable, emulators required coax adapter cards to be installed in the PC. Today, many emulators communicate with the mainframe computer through the TN3270 variant of the Telnet protocol common on TCP/IP networks including the Internet, so special hardware is no longer required.
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