If you have not split a composite USB device, Horizon 8 applies the filter policy settings to the entire device. If you have split a composite USB device, Horizon 8 examines each of the device's interfaces to decide which should be excluded or included according to the filter policy settings. Horizon 8 applies any device splitting policy settings before it applies the filter policy settings. When you connect to a desktop or application, Horizon Client downloads the Horizon Agent USB policy settings and uses them in conjunction with the Horizon Client USB policy settings to decide which USB devices it will allow you to redirect from the client computer. USB device filtering is often used by companies to deactivate the use of mass storage devices on remote desktops, or to block a specific type of device from being forwarded, such as a USB-to-Ethernet adapter that connects the client device to the remote desktop. Filter policy settings that you configure for Horizon Agent and Horizon Client establish which USB devices can be redirected from a client computer to a remote desktop or application.