Telnet is an Internet-standard utility and protocol based on Request for Comments (RFC) 854. This RFC specifies a method for transmitting and receiving unencrypted ASCII characters (plaintext) across a network. You can use a Telnet client running on one computer to connect to a command line-based session to run applications. Only character-based interfaces and applications are supported. There is no graphics capability in the Telnet environment.

The RFC documents that define Telnet can be found at the Internet Engineering Task Force Web site ( On that page, click RFC Pages, and then type 854 in the RFC number text box and click Go.

Telnet consists of two components: Telnet Client and Telnet Server.

Telnet Client

Telnet Client allows a computer to connect to a remote Telnet server and run applications on that server. Once logged on, a user is given a command prompt that can be used as if it had been opened locally on the Telnet server's console. Commands that you type at the Telnet client command prompt are sent to the Telnet Server and executed there, as though you were locally logged on to a command prompt session at the server. Output from the commands that you run are sent back to the Telnet client where they are displayed for you to view.

Telnet does not support applications that require a graphical user interface. However, Telnet Server and Telnet Client understand special character sequences that provide some level of formatting and cursor positioning within the Telnet client window. Telnet Server and Telnet Client support the emulation of four types of terminals: ANSI, VT-100, VT-52, and VT-NT.

Installing Telnet Cient

On Windows Server 2008, you can install Telnet Client by using the Add Features Wizard in Server Manager. Although Server Manager opens by default when a member of the Administrators group logs on to the computer, you can also open Server Manager by using commands on the Start menu in Administrative Tools, and by opening Programs in Control Panel. On Windows Vista and later versions, you can install Telnet Client (and Telnet Server) by opening Control Panel, then Programs, and then Turn Windows features on or off.

For more information about installing or using Telnet Client, see the Telnet Operations Guide ( on the Microsoft Web site.