What Is Telnet? Introduction to Teletype Network Protocol

Aaron Paul updated on Dec 16, 2022 to Knowledge Center

Do you want to know what is Telnet? Telnet stands for Teletype Network, which was established in 1969. It's a communication protocol through which remote interaction is made possible within a secured environment. Through this protocol, one can connect his system to a remote computer. Once the connection is made successfully, you can access the remote computer's operations through the local computer.

what is telnet

Telnet protocol uses the principle of a client/server program. The local computer that starts the connection uses a client program. On the other hand, a remote computer accepts the connection and works through the server program. Hence, the Telnet protocol enables remote management and communication effortlessly.

How Does Telnet Work

When it comes to the functionality of Telnet, this protocol offers users an interactive bidirectional text-oriented message system. For this, it uses an essential virtual terminal connection that is more than 8 bytes. It further allows users to test the connectivity of remote devices. Also, users can give commands through a keyboard.

If you want to connect to the server, you can follow the Telnet protocol. You can use the syntax "Telnet Hostname Port" in a command prompt to establish a connection. Afterward, you can use the Telnet prompt to give Telnet commands to the server. Thus, you can connect to the server using the Telnet protocol for remote interaction.

What Is Telnet Used For

Telnet is a secure communication protocol that you can use to connect one computer to another local computer or network component. There are various uses of the Telnet protocol that you can learn from this section.

  1. Bigger institutions widely use Telnet to navigate to large databases. People can access digital publication databases through the libraries' local network using the Telnet protocol.
  2. You can use Telnet to locate text-based programs like Free Internet Chess Server. So, the Telnet protocol made it possible to communicate with the programs within application servers.
  3. This protocol is also used to establish a two-way communication service between local area networks (LAN) and the Internet.
  4. As Telnet is a text-based protocol, you can use it to participate in online communities. You can access the Telnet BBS Guide to discover various BBSes for participation.

Telnet Vs. SSH

SSH is another famous network protocol that many people use for remote management. In this section, we will discuss the key differences between Telnet and SSH to offer you a better understanding:

Telnet SSH
Telnet utilizes port 23 of TCP/IP by default and works to establish a connection between the local area network and remote computer.  SSH uses port 22 of TCP and provides more secure access to remote machines.
Telnet has various vulnerabilities when it comes to security.  SSH offers a highly secure and safe medium to connect with remote machines. Moreover, it can even reach unsecured networks efficiently. 
Telnet is based on a text-based interface, so it transfers the data in a simple text format.  SSH protocol prioritizes security as it sends encrypted data. 
This network protocol does not use any authentication process to check the user's identity. This protocol utilizes public key encryption for its authentication process.
As Telnet has security vulnerabilities, this protocol is recommended for private networks.  SSH provides an excellent security medium to send data. Thus, it's ideal for public networks.

Telnet FAQs

After discussing the usage and purpose of Telnet protocol, we will now address some of the commonly asked questions for your convenience.

1. Is Telnet a TCP or UDP?

To establish a connection for remote management, Telnet utilizes TCP/IP (Transmission Control Protocol/ Internet Protocol).

2. What is the port for Telnet?

This network protocol uses the 23 TCP port by default for establishing a connection.

3. Is Telnet secure?

Telnet has various security vulnerabilities as it does not rely upon a security mechanism. Moreover, it does not use an authentication process and sends the data, including passwords, in the form of text format. Thus, anyone can misuse the text-based information for the wrong purposes.

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