SSH service is not enabled by default in Ubuntu both Desktop and Server, but you can easily enable it just by one command. Works on Ubuntu 13.04, 12.04 LTS, 10.04 LTS and all other releases.
And the command is:
sudo apt-get install openssh-server
It installs OpenSSH server, then automatically enable ssh remote access.
OpenSSH is a FREE version of the SSH connectivity tools that technical users of the Internet rely on. Users of telnet, rlogin, and ftp may not realize that their password is transmitted across the Internet unencrypted, but it is. OpenSSH encrypts all traffic (including passwords) to effectively eliminate eavesdropping, connection hijacking, and other attacks. Additionally, OpenSSH provides secure tunneling capabilities and several authentication methods, and supports all SSH protocol versions.
You can edit the config file “/etc/ssh/sshd_config” to change default port 22, remember to apply changes via the command below:
sudo /etc/init.d/ssh restart