What is ? OpenSSH is a free open source set of computer tools used to provide secure and encrypted communication over a computer network by using the ssh protocol. Many people, new to computers and protocols, create a misconception about OpenSSH , they think it is a protocol, but it is not, it is a set of computer programs that use the ssh protocol . Why Open SSH ? The most important reason why should use OpenSSH tools over ftp and telnet is that all communications and user credentials using OpenSSH are encrypted, they are also protected from man in the middle attacks. If a third party tries to intercept your connection, OpenSSH detects it and informs you about that. Installation ? sudo apt-get update $ sudo apt-get install openssh-server openssh-client $ sudo ufw allow 22 Links : https://help.ubuntu.com/community/SSH/OpenSSH/Configuring http://www.tecmint.com/install-openssh-se...