"You can run out to www.openssh.org to get the latest
and greatest, but you probably already have it on your system. That
said, keeping up to date with the latest version of OpenSSH is
essential if you want to maintain security. So, if your version of
OpenSSH is more than a few months old, you may want to consider
checking for an update.
"OpenSSH has several components: a client and server, utilities
for generating public and private encrypted keys for strong
authentication and a secure FTP server. Before you log in using a
secure shell, you need to start a secure server, which usually
happens at boot time through a script in /etc/init.d or
/etc/rc.d/init.d, depending on your system. Look there for a script
called simply sshd. You also can start the sshd daemon by typing
sshd at the shell."