For this tutorial I make the assumption both computers are on the local network and I use Remmina as the application for VNC access.

On the host computer:

1. Go to Preferences > Remote Desktop and select the following preferences:
   1. Check "Allow other users to view your desktop";
   2. Check "Allow other users to control your desktop";
   3. Check the security settings you desire;
2. Install openssh-server;
3. Just to be sure, open a terminal window and test your new ssh server with the following command "ssh -l username ipaddress", where username is the name of the user you wish to log in as and ipaddress is the IP address of your system. You can also substitute the hostname of the system in place of the IP address. The test can be made from a remote system or from your local system. If you see the SSH server answering then everything is OK.

On the client computer:

1. Install Remmina (a VNC client);
2. Go to Accessories > Password and Encryption Keys and add a key to connect to the remote server:
   1. File > New;
   2. Secure Shell Key;
   3. On Key Description put anything you like;
   4. Select the button "Create and Set Up";
   5. Select a password;
   6. Insert the IP address or hostname of the host system as well as a valid user;
   7. Insert the previous user password (of the host system user, not the 2.5 password).
   8. Your key was created. You can check it if you desire on the host system "Password and Encryption Keys", on the "Other Keys" tab (if it uses Linux Mint), and on the local system on the "My Personal Keys" tab.
3. Start Remmina and create a new connection:
   1. Edit > New;
   2. Fill the fields for "Name", "Group" (optional), "Server" (your host system IP address or hostname), "Color Depth (optional), Quality (optional). Select as protocol "VNC - Virtual Network Computing";
   3. Go to the SSH tunnel tab and check "Enable SSH Tunel" and fill the field "User Name" with the username you used on 2.6;
   4. Select the button "Connect";
   5. Insert the password you inserted on 2.5;
   6. You should be connected with SSH!