Terminal network Telnet is an application protocol used on the Internet or local area network to provide a bidirectional interactive text-oriented communication facility using a virtual terminal connection. User data is interspersed in-band with Telnet control information in an 8-bit byte oriented data connection over the Transmission Control Protocol (TCP).
NVT chatacter set is a universal interface defined by telnet to ensure user can access any remote computer.
Historically, Telnet provided access to a command-line interface on a remote host. Telnet transfers data in plain text. Because of serious security concerns when using Telnet over an open network such as the Internet, its use for this purpose has waned significantly in favor of SSH.