SSH vs Telnet: How Is SSH Different From Telnet?

Learn the key differences between Secure Shell (SSH) and Telnet protocols, so you can choose the right one for your security needs.
SSH vs Telnet: How Is SSH Different From Telnet?

In the realm of computer networking, secure remote access plays a vital role in ensuring data confidentiality and system integrity. When it comes to accessing remote systems, two popular protocols come to mind: SSH (Secure Shell) and Telnet. Both protocols serve a similar purpose, but they differ significantly in terms of security and functionality.

This article aims to shed light on the differences between SSH and Telnet, helping you understand why SSH has become the preferred choice for secure remote access.

Table of Contents

  1. What is SSH?
  2. What is Telnet?
  3. What’s the Difference Between SSH and Telnet?

What is SSH?

Secure Shell (SSH) is a cryptographic network protocol that enables secure communication between two networked devices. It provides a secure channel over an unsecured network by encrypting data sent between the client and the server. SSH was designed as a secure alternative to protocols like Telnet and rlogin, which transmit data in plain text.

SSH Features

SSH incorporates various features that contribute to its security and functionality. These include:

  • Encryption: SSH encrypts the data transmitted between the client and the server, preventing unauthorized interception and eavesdropping.
  • Authentication: SSH utilizes various authentication methods, such as passwords, public key authentication, and certificates, ensuring that only authorized users can access the system.
  • Port Forwarding: SSH allows the forwarding of network connections from one host to another, facilitating secure remote access to services on a local network.
  • File Transfer: SSH includes secure file transfer capabilities through tools like Secure Copy (SCP) and Secure File Transfer Protocol (SFTP).
  • Tunneling: SSH can create secure tunnels to encapsulate other network protocols, such as HTTP, FTP, or database connections, providing an added layer of security.

These tools make SSH an effective tool for secure remote access and data transfer.

What is Telnet?

Telnet is a networking protocol that combines the terms "Telecommunications" and "Networks." It is primarily associated with the UNIX platform and is designed for local area networks. Telnet facilitates remote connections to computers, enabling a text-based communication channel for collaborative interaction between the two systems.

Using TCP/IP (Transmission Control Protocol/Internet Protocol), Telnet establishes remote sessions between two computers. It is frequently utilized by computer users who require access to specific data or programs on remote systems.

Telnet suffers from several limitations that make it less secure and practical for modern network environments. For example, Telnet transmits data in plain text, making it susceptible to eavesdropping and unauthorized access to sensitive information. Telnet also relies on basic username and password authentication, which can be easily compromised.

What’s the Difference Between SSH and Telnet?

The most significant differences between SSH and Telnet sum up to a few different categories ranging from security to functionality.

SSH vs Telnet: Comparison Overview

The following table summarizes the key differences between SSH and Telnet.





Telnet is a way for computers to talk to each other, especially on UNIX systems. The name comes from two words, "Telecommunications" and "Networks".

SSH, also known as Secure Shell, allows you to remotely log into another computer and execute commands or transfer files over a network.


Telnet is designed for local area networks and it uses port 23.

SSH typically uses port 22 as its default, but it can be easily modified.


Telnet is less secure when compared to SSH.

The information shared and sent through SSH is encrypted, making it a highly secure protocol.

Data format

Telnet transfers data in a simple, unencrypted plain text format.

SSH utilizes both encryption and a secure channel for transmitting data.


Telnet does not offer user authentication or privileges.

SSH authentication uses public key encryption for enhanced security.


Telnet is only recommended for use in private networks.

SSH is appropriate for use in public networks.


SSH vs Telnet: Operation

Telnet and SSH are two ways to control computers remotely, but they have important differences in how they keep things secure. Telnet works by installing a special program on the computer you want to control (called the server) and another program on your own computer (called the client). These programs talk to each other using a special language over the internet. However, the problem with Telnet is that it sends everything in plain text.

SSH, on the other hand, focuses on making sure your connection is secure and private. It requires a program on both the server and your own computer. To establish a secure connection with a server using SSH, the client first verifies the server on port 22 (or a different port number of your choice). With key-based authentication, a session key is generated and shared between the client and server to encrypt the traffic during the session. The client is then verified by the server using an SSH key pair, and once authentication is completed, both systems can exchange data securely over the encrypted connection.

To use SSH on Windows, it is necessary to have an SSH client like Putty.

SSH vs Telnet: Security

Telnet doesn't have built-in security measures to protect the information being sent. It sends data in plain text, which means that anyone who can intercept it can see and even change the information. This makes Telnet risky to use, especially on public or untrusted networks where there is a greater chance of unauthorized access.

SSH is a much more secure way of transferring data over unsecured networks. When SSH sessions use key pairs for authentication, it becomes extremely difficult for anyone to decrypt and read the data being exchanged. This is because the data is encrypted using special codes known as keys, and only the intended recipient with the correct key can unlock and understand the information.

The encryption used by SSH ensures that even if someone intercepts the data, they won't be able to make sense of it. As a result, SSH is a preferred choice for secure remote access and data transfer, especially when operating in environments where security is a concern.

SSH vs Telnet: Data Formats

Telnet is a network protocol that transmits data in a plain text format known as the Network Virtual Terminal. In contrast, SSH employs an encrypted format for data transfer, ensuring a secure connection between client and server.

While Telnet sends information in clear, readable text, SSH encrypts the data, providing confidentiality and protecting it from unauthorized access. By utilizing strong cryptographic techniques, SSH establishes a secure channel, preventing potential eavesdropping and ensuring the integrity of the transmitted data.

This fundamental distinction between Telnet and SSH highlights the importance of employing secure protocols to safeguard sensitive information in today's interconnected world.

SSH vs Telnet: Authentication

Telnet does not employ any authentication methods during the process of establishing a connection.

In contrast, the widely used and highly secure authentication method for SSH is public key authentication. In this method, when an SSH key pair is created, the client retains the private key, while the public key is transmitted to a server.

When a client attempts to connect to a server via SSH, the server verifies the client's identity by comparing the public key with the private key. If the keys are a match, the two systems can establish a secure and encrypted connection.

SSH vs Telnet: Preference

Using SSH instead of Telnet is highly recommended for connecting to remote systems over the internet, especially on public networks, due to its increased security features. SSH also offers additional functionality like secure file transfer and port forwarding. However, there are two specific situations where it is advisable to choose Telnet instead of SSH:

  • When operating within reliable and secure networks like LANs that have no connection to the Internet.
  • When dealing with devices that do not have support for SSH.

Telnet's security risks are not an issue in these scenarios, and its lower bandwidth usage is an advantage. Telnet is generally recommended only for private networks because it has fewer security measures.


To sum it up, SSH and Telnet are two popular methods for remote access. While both offer a means of connecting to a computer from another location, the primary difference lies in the level of security offered by each protocol. Ultimately, choosing between Telnet and SSH depends on the user's needs and requirements in terms of network security.

We hope that this article has helped you understand the similarities and differences between Telnet and SSH. While both offer a viable solution for remote access, for greater peace of mind, always use SSH when connecting to remote systems over public networks.

One More Thing

We’re glad you’ve read this article. :) Thank you for reading.

If you have a second, please share this article on your socials; someone else may benefit too. 

Subscribe to our newsletter and be the first to read our future articles, reviews, and blog post right from your inbox. We also offer deals, promotions, and updates on our products and share them via email. You won’t miss one.

Related Articles

» Windows 11 Text Editors: Notepad vs WordPad
» Cloud Comparison: AWS vs Azure vs Google Cloud
» What Is the System32 Folder? System32 vs SysWOW64