Telnet vs SSH – Difference Between Them

Key Difference between Telnet and SSH

Telnet is the standard TCP/IP protocol for virtual terminal service, while SSH or Secure Shell is a program to log into another computer over a network to execute commands in a remote machine.
Telnet is vulnerable to security attacks while SSH helps you to overcome many security issues of Telnet .
Telnet uses port 23, which was designed specifically for local area networks, whereas SSH runs on port 22 by default.
Telnet transfers the data in plain text while in SSH data is sent in encrypted format via a secure channel.
Telnet is suitable for private networks. On the other hand, SSH is suitable for public networks.

What is Telnet?

Telnet is the standard TCP/IP protocol for virtual terminal service. It enables you to establish a connection to a remote system in such a manner that it appears as a local system. The full form of TELNET is Terminal Network.

Telnet protocol is mostly used by network admin to access and manage network devices remotely. It helps them access the device by telnetting to the IP address or hostname of a remote device. It allows users to access any application on a remote computer. This helps them to establish a connection to a remote system.

What is SSH?

SSH is a network protocol that is widely used to access and manage a device remotely. The full form of SSH is Secure Shell is a major protocol to access the network devices and servers over the internet.

It helps you to log into another computer over a network and allows you to execute commands in a remote machine. You can move files from one machine to another. SSH protocol encrypts traffic in both directions, which helps you to prevent trafficking, sniffing, and password theft.

Telnet vs SSH: Comparison Overview

Here are some major differences between Telnet and SSH:

Telnet	SSH
Telnet is the standard TCP/IP protocol for virtual terminal service. It enables you to establish a connection to a remote system in such a manner that it appears as a local system.	SSH or Secure Shell is a program to log into another computer over a network to execute commands in a remote machine.
Telnet uses port 23, which was designed specifically for local area networks	SSH runs on port 22 by default, which you can change it.
No privileges are provided for the user’s authentication.	SSH is a more secure protocol, so it uses public-key encryption for authentication.
Suitable for private networks	Suitable for public networks
Telnet transfers the data in plain text.	The encrypted format should be used to send data and also uses a secure channel.
Telnet is vulnerable to security attacks.	SSH helps you to overcome many security issues of Telnet.
Required low bandwidth usage.	Required high bandwidth usage.
Data sent using this protocol cannot be easily interpreted by the hackers.	Usernames and Passwords can be prone to malicious attacks.
Used in Linux and Windows Operating system.	All popular Operating systems.

Important Telnet Commands

Here are some important Telnet commands:

Open: This telnet command is used to open the host name port number to establish a Telnet connection to a host
Close: Helps you to close an existing Telnet connection
Quit: To exit from Telnet
Status: Use this command to determine whether the Telnet client is connected or not.
Timing Mark: Defines the timing marks
Terminal Type/Speed: Set the terminal type and speed.

Important SSH Commands:

Here are some important SSH commands

ls- Show directory contents (list the names of files).
cd– This command helps you to change the directory
mkdir– Helps you to create a new folder (directory).
touch– Allows you to remove a file.

Advantages of Telnet

Here are pros/benefits of Telnet

This protocol can be used to send and receive information
Supports user authentication
The collaboration of multiple users
You can use to send and receive information
This remote login saved your research hours
There are no authentication policies & data encryption techniques used in Telnet, causing a huge security threat.

Advantages of SSH

Here are pros/benefits of SSH protocol:

It is available free for non-commercial use
The open-source version has gone through improvements like bug fixes, patches, and offers many additional functionalities.
SSH may offer multiple services using the same connection
SSH helps you to securely tunnel insecure applications like SMTP, IMAP, POP3, and CVS.
The tunnelling of ports works effectively for simple VPNs.
It offers strong authentication and secure communications over insecure channels.
SSH allows users to log into another computer over an insecure network securely.
Provide privacy of your data via strong encryption.
The integrity of communications performed in such a way that it cannot been altered.
Authenticate proof of identity of senders and receivers.
Allows you to back or forward or to encrypt other TCP/IP- based sessions.
Allows the user to view the contents of directories, edit files, and access custom database applications remotely.

Disadvantage of Telnet

Here are the cons/drawback of the Telnet protocol:

Telnet is not an Ideal Protocol to transmit cursor movements or GUI information.
Does not support the transport of encrypted data. Instead, it only supports known port number
Dynamic port not supported
Telnet does not encrypt any data sent over the connection.
Port numbers can be exploited.
Display only text and numbers, no graphics and color

Disadvantage of SSH

Here are the cons/drawback of using SSH:

Telnet connection does not allow you to run GUI tools.
It is not designed to transmit cursor movements or GUI movement information.
It is not a secure protocol.
SSH protocol not able to fix all TCP’s problems since TCP runs below SSH.
SSH cannot protect users from attacks made through other protocols.
This protocol does not protect Trojan horses or viruses.