HomeDefinitionsSSH - Secure Shell: Definition, Uses & Importance

SSH – Secure Shell: Definition, Uses & Importance

SSH, or Secure Socket Shell, is a network protocol that allows administrators to securely access a computer remotely. SSH also refers to all the utilities that implement the protocol.

The Secure Shell protocol provides strong authentication and secure encrypted data communications between two computers connected over an insecure network, such as the Internet.

SSH is widely used by network administrators to remotely manage systems and applications, as it allows them to connect to another computer on a network, run commands, and move files from one computer to another.

Basically, It is a protocol that allows you to connect to a remote machine with a secure connection. The data are encrypted between machines. It allows executing commands on a remote server.

SSH’s Importance

SSH stands for both the cryptographic network protocol and the utilities that implement that protocol. SSH works on the client-server model, connecting a Secure Shell client application – where the session appears – to an SSH server – where the session runs.

Most operating systems, except Microsoft Windows, include SSH by default. SSH supports tunneling, which forwards arbitrary TCP ports and X11 connections, while file transfer can be done using the associated Secure File Transfer Protocol (SFTP) or Secure Copy Protocol (SCP) protocols. By default, an SSH server listens on standard TCP port 22.

The SSH suite includes three utilities (slogin, ssh, and scp), which are secure versions of earlier insecure UNIX utilities (rlogin, rsh, and rcp). SSH uses public key encryption to authenticate the remote computer and allow it to authenticate the user, if needed.

SSH Protocol’s History and Advancements

The first version of SSH was created in 1995 by Tatu Ylönen, a researcher at Helsinki University of Technology and founder of SSH Communications Security. Gradually, vulnerabilities were discovered in SSH-1, now obsolete.

The current version of Secure Shell protocols is SSH-2, the standard adopted in 2006.

It is not compatible with SSH-1 and uses Diffie-Hellman key exchange and strong integrity checking that relies on message authentication codes to improve security.

SSH clients and servers can use various encryption methods, the most common being AES and Blowfish.

Currently, there are no known exploitable SSH2 vulnerabilities, but information disclosed by Edward Snowden in 2013 suggests that the National Security Agency is able to decrypt some SSH traffic.

Shellshock, a Bash command processor security flaw, can be executed over SSH, but it is a vulnerability in Bash, not SSH. In fact, the biggest threat to SSH is poor key management.

Indeed, in the absence of a proper centralized process for creating, rotating and deleting SSH keys,

companies risk losing complete control over resource access permissions, especially when SSH is used in automated inter-application processing.

Mehmet S. Kaya
Mehmet S. Kayahttps://teknonel.com
Mehmet is one of the administrator of Teknonel. As a software developer, he loves to share his knowledge in related topics. He is highly familiar with the editorial process from the inception of an article idea, through the iterative process, publishing, and performance analysis as well as product reviews.

Follow us on Social Media!


Related Articles

HDR: Definition, Advantages and Importance

HDR stands for "High Dynamic Range". The goal is to translate as well as possible, on a photo or a video, what the human...

Keylogger: Definition, Prevention and Types

The term keylogger is used to designate any computer process (software or hardware) capable of recording the sequences of keys typed on a keyboard,...

Hyperthreading: Definition, Uses and Importance

Threads are small tasks that the computer must perform simultaneously, that is to say operations that one or more open programs must execute and...

Geofencing: Definition, Uses and Importance

Geofencing is a geolocation technology that monitors the movement of objects or people within a predefined perimeter. This system is used, for example, for...

Explore More Articles

superconducting material Uranium Ditelluride-min

A breakthrough in the new superconducting material “Uranium Ditelluride”

Scientists have discovered a new crystalline superconducting state in a new and unusual superconductor called uranium ditelluride, a wonder material that can make extremely...
Starfield How to upgrade Ship Weapons-min

Starfield: How to upgrade Ship Weapons?

Within Starfield you can actually purchase upgrade or fully build your own spaceship via modules. The thing is that, a lot of this isn't...
OpenAI Will there be GPT-5

OpenAI’s first developer conference: Will there be GPT-5?

OpenAI will hold its first developer conference, OpenAI DevDay, on November 6, two months later. During the full-day event, the OpenAI team will lead...
Starfield How to Store items in your Ship-min

Starfield: How to Store items in your Ship?

Starfield's massive open-world comes with unlimited items to farm and collect. However, it might be little bit annoying to over encumber time to time....