Sure just install a ssh server. You should also probably route the vnc over the ssh but i am not gonna focus on that.
The ssh server does basically what the vnc does but for tty (not for the gui). It is capable of many things but is mostly use as a way to display a terminal window to a remote computer so you can use commands from the remote computer.
You can install it by using
sudo apt-get install openssh-server and the server/service should start automatically after the installation (and at startup)
The server listens to port 22 and to login you only have to use your username and password as you would in a tty.
to test the server from any linux installation just open a terminal and type:
ssh 'your username'@'your ip'
and then type your password. If the ssh client is not installed you can install it by
sudo apt-get install openssh-client
if you want to connect to your pc from a windows installation you can use the program putty (free, google it :P)