If you like computing, surely you have heard of Telnet . This communication protocol is considered the predecessor of the Internet, and although it is a technology that is already outdated, in its day it was tremendously popular.
Although Telnet has been superseded by more secure protocols like SSH, it can still be used today on modern Windows and Linux systems. Almost more like a curiosity than anything else, although the truth is that it has its point.
What is Telnet?
Telnet is a network communication protocol that is controlled by a text command interface . Its purpose is to offer a communication system between two devices connected to the Internet or to the same local area network.
Mainly, Telnet is known for being the original protocol used in that first internet that was born back in 1969, and if you are still wondering, its name is an acronym for TELetype NETwork , TERminaL NETwork or TELecommunications NETwork , depending on the source let us consult
What was Telnet originally used for?
Telnet was developed as a convenient solution for accessing university servers without requiring students and faculty to travel to campus.
In the years when Telnet was born, if you wanted to work with the data that was stored in the big computers at the university, you had to go there first, and then you had to queue until it was your turn to use it.
Even if the server hardware was powerful enough to multitask, users could only work one at a time. In many cases they weren’t even allowed to be in front of the server, instead having to wait with the punch card in hand until an attendant came to collect it and then return with the results.
Telnet was a huge change in this regard. Students and teachers could simultaneously connect to the server and work much more productively. They just needed access to a terminal with a network connection and a text interface.
Why has it fallen into disuse?
Today Telnet has ceased to be used because it is a protocol that does not offer any type of security, since communications are not encrypted and it is vulnerable to all kinds of attacks.
40 or 50 years ago, cyber attacks were not as frequent as they are now. Today, however, the situation is very different and it is normal to use web interfaces that offer a higher degree of security to control devices remotely.
Over time, Telnet has evolved into more secure network protocols, such as SSH or Secure Shell , which have consistent authentication systems and data encryption in communications.
How to activate Telnet in Windows 10/11
As we said, it is no longer common to use Telnet to connect remotely to another computer or server. However, it still comes installed out of the box on some versions of Windows.
- Telnet server: If you want your PC to act as a Telnet server you can still do it. Unfortunately this feature is only available in older versions like Windows XP or Windows 7.
- Telnet client: What you can do in both older and newer versions of Windows is to use the Telnet client to connect to other remote Telnet servers. Let’s see how it works.
The first thing to say about the Windows Telnet client is that it is disabled by default . To activate it we have two ways to do it: using an activation command, or using the Windows Control Panel.
Install the Telnet client from Control Panel
- Press the Win+R key combination and run the command “control.exe” (without quotes).
- Inside the Windows Control Panel, go to “ Programs -> Programs and Features -> Turn Windows features on or off”.
- Check the “Telnet Client” box.
- Finally, click “OK” to apply the changes and enable the Telnet client on the PC.
Enable the Telnet client using a command
Instead of using the Control Panel we can also activate Telnet by executing a certain command from a terminal window.
- Open Windows folder explorer and go to “ C:\Windows\System32\” and locate the file “cmd.exe”. Right click on it and select “Run as administrator”.
- Inside the terminal window run the following command:
- dism /online /Enable-Feature /FeatureName:TelnetClient
If everything has gone well, in a matter of seconds a message will appear indicating that “the operation was completed correctly”.
Basic Telnet Commands
These are some of the most basic commands that we can find available in the Telnet protocol.
| Command | Meaning | Description |
| c | close | Close the current connection |
| d | display | Shows the parameters of the operation |
| o | open hostname [port] | Connect to a server (port 23 by default) |
| q | quit | Quit Telnet |
| set | set | Set options (type ‘set ?’ to see a list) |
| sen | send | Send a string of characters to the server |
| st | status | Print status information |
| u | unset | Undo options (type ‘unset ?’ to see a list) |
| ?/h | help | show help |
Although Telnet has practically disappeared due to its lack of security, we can still find some old school servers that use this system.
- Open a terminal window in Windows and type the command “telnet” (without quotes). This will open the Telnet client.
- Type the command “ o freechess.org 5000” (without quotes) to access a Telnet server to play an online chess game.
- You can also use the command “ o towel.blinkenlights.nl” (without quotes) to play the entire Star Wars movie (Episode IV) in ASCII format. One last.
If you know other useful commands for Telnet or want to share a server that is still active, do not hesitate to drop by the comments area.
