[4] It uses the RFB (VNC) protocol to allow a computer to access and control another one remotely over a network connection.

However, in addition to remote control, it adds various features, such as an encryption plugin to secure the client/server connection.

The software is free and distributed under the terms of the GNU General Public License.

It can use an optional mirror driver installed on the remotely controlled computer for fast and efficient notification of screen changes with very low CPU load,[5] although this is not needed since later versions of Windows 10.

Since release 1.0.6.4, UltraVNC server can work as a Windows service under User Account Control (UAC).