Secure Shell (SSH) protocol
In the DevOps world, almost nothing runs locally on your laptop or PC. There is one golden standard among ways to reach remote systems and it’s the SSH protocol. SSH was developed in 1995 as a secure, encrypted remote shell access tool that would replace plaintext utilities such as telnet or rsh. The main reason for this is that in distributed networks, it is too easy to eavesdrop on communication and anything that is being transmitted in open text can easily be intercepted. This includes important data such as login details.
The most commonly used SSH server (and the client) in the Linux world is OpenSSH (https://www.openssh.com/). Other open source servers that are still maintained at the time of writing are lsh (http://www.lysator.liu.se/~nisse/lsh/), wolfSSH (https://www.wolfssl.com/products/wolfssh/), and Dropbear (https://matt.ucc.asn.au/dropbear/dropbear.html).
SSH is mainly used to log into a remote machine to execute commands. But it...