The Teletype network, otherwise known as Telnet, is a network protocol that's responsible for maintaining a bidirectional interactive communications facility on the Internet or Local Area Networks (LANs). Usually, Telnet offers users access to an interface of the command line variety on a remote host through a virtual terminal link that's composed of an eight-bit, byte-based data connection over TCP (Transmission Control Protocol). From there, user information is mixed together in-band with Telnet control information.
All the same, Telnet is a severely outdated network protocol
And the SSH (Secure Shell) protocol is leaps and bounds better than this rather obsolete standard when it comes to remotely transmitting information through a secure channel between two linked devices or computers. Nevertheless, when it was developed and released back in 1969, Telnet was one of the first cutting-edge technologies out there. Arguably, without Telnet, there won't be any SSH. Its rich history includes its beginnings with RFC 15, extensions in RFC 854, and standardization as IETF (Internet Engineering Task Force) Internet Standard STD 8, which was one of the first online standards ever instituted.
The Telnet term may also refer to the program that applies and employs the client function of the protocol as well.To be true, Telnet-based client applications are readily available for nearly all operating systems (OS). Most mediums and network equipment that sport the TCP/IP stack are compatible with the Telnet service's remote configuration capabilities, particularly modern platforms such as Windows NT and all its variants. However, despite Telnet's widespread OS support and compatibility, its multitude of security issues has made it trail behind its successor, SSH.
"Telnet" can be used as a verb as well, in the sense that "to telnet" means to setup or launch a link with the Telnet protocol either with an application interface or with a command line client. For example, a typical directive of telnet may entail, "To create a stronger password for your server, you must first telnet to it, login, and execute the password editing command known as 'passwd'." More likely than not, a user will be telnetting to a Unix-based network paraphernalia (e.g., a router) or server system in order to access a login prompt via a character-based, full-screen manager or a command line text interface.