In knoppix,
cd /etc/apt/
nano sources.list
add any good debain repo such as
deb http://http.us.debian.org/debian stable main contrib non-free then : Save the file then : apt-get update then type: apt-get install openssh-server also , give a password to root because currently knoppix does not have any root password. repo ref: http://www.debian.org/doc/manuals/apt-howto/ch-basico.en.html