Telnet is a protocol suite that gives the user the opportunity to be on one computer system and do work on another, which may be across the street or thousands of miles away. Telnet is still the main Internet protocol for creating a connection with a remote machine.

Telnet basically makes the computer believe that your computer is an ASCII character based terminal. Telnet handles the remote login to another Internet host. The Telnet protocol has been implemented on a variety of systems. Each is different, so specific commands depend on your version. However, all versions function similarly.

Telnet operates in a client/server environment in which one host (the computer you are using, running Client (User) Telnet) negotiates opening a session on another computer (the remote host, running Server Telnet). During the behind-the-scenes negotiation process, the two computers agree on the parameters governing the session.

One of the first things they settle is the terminal type to be used -- in general, a line-by-line network virtual terminal, for simplicity's sake. Virtual terminal, in this context, refers to a set of terminal characteristics and sequences that both sides of a network connection agree to use to transmit data from terminals across the network, regardless of the terminal used.

Using Telnet

The commands for negotiating a telnet connection varies from system to system. The most common is telnet itself, though. The most common command is for telnet itself,

• telnet somewhere.domain

If you know your site domain name you open the connection, by typing,

• telnet your.system.name

If the system were yahoo.cs.berkeley.edu, for example, the command would look like

• yahoo.cs.berkeley.edu

The responce from the system would be something similar to,

• Trying 167.34.284.977...
  Connected to yahoo.cs.berkeley.edu
  Escape character is '^]'.

The "^]" command is the character which allows you back to the local system or for closing the connection.