With default configuration, Windows RDP service is running on port 3389, to protect your server, you can change the RDP port.
1. Run "regedit", expand the folders to:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Terminal Server\WinStations\RDP-Tcp
Find the "Port number" entry and double-click on it. In opened window choose "Decimal" and change "Value data" to desired port, and click OK.
2. Expand the folders to:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Terminal Server\Wds\rdpwd\Tds\tcp
Find the "Port number" entry and double-click on it. In opened window choose "Decimal" and change "Value data" to desired port(this value should be same as above), and click OK.
3. Open the new RDP port in Windows Firewall (MUST do this before reboot, or your server will be inaccessible via RDP).
4. Reboot your server.
5. Connect you server with new port(example: vm00.sakuraserver.com:9999).
