The Secure Shell Protocol (SSH) is a cryptographic network protocol for operating network services securely over an unsecured network.[1] Its most notable applications are remote login and command-line execution. SSH was designed for Unix-like operating systems as a replacement for Telnet and unsecured remote Unix shell protocols, such as the Berkeley Remote Shell (rsh) and the related rlogin and
![Secure Shell - Wikipedia](https://cdn-ak-scissors.b.st-hatena.com/image/square/dbbb80b31b2ba80753e61a44676d486d6dc0e26f/height=288;version=1;width=512/https%3A%2F%2Fupload.wikimedia.org%2Fwikipedia%2Fcommons%2Fthumb%2F0%2F03%2FX11_ssh_tunnelling.png%2F250px-X11_ssh_tunnelling.png)