SSH provides a secure channel over an unsecured network by using a client–server architecture, connecting an SSH client application with an SSH server.

The protocol specification distinguishes between two major versions, referred to as SSH-1 and SSH-2.

The standard TCP port for SSH is 22. SSH is generally used to access Unix-like operating systems, but it can also be used on Microsoft Windows. Windows 10 uses OpenSSH as its default SSH client and SSH server. Wikipedia

• Putty is a windows ssh client application: https://www.chiark.greenend.org.uk/~sgtatham/putty/
• OpenSSH is a client and server: https://www.openssh.com/

• Example commands with puttygen
• Disable username + password login in sshd
• Cipher config and documentation
• OpenSSL commands and documentation